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Title:
LIGHT BASED DENTAL TREATMENT DEVICE
Document Type and Number:
WIPO Patent Application WO/2018/009864
Kind Code:
A1
Abstract:
A light based dental treatment device (100) includes a handle (102) configured for placement within the oral cavity of a user. An instrument shaft (104) extends from the handle (102). An instrument profile of the instrument shaft is configured for delivery into a passage or cavity of a tooth. The instrument shaft (104) includes at least one light delivery port (116) at a distal end portion (108) of the instrument shaft (104), and a light passage (112) extending at least from the handle (102) to the light delivery port (116). A light source (110) is in communication with the light delivery port (116) through the light passage (112). The light source (110) is configured to generate light in one or more wavelengths including ultraviolet wavelengths.

Inventors:
MORIO, Kimberly Ann (3183 Stillwater Cove NE, Solon, Iowa, 52333, US)
DRAKE, David Ray (911 Talwrn Court, Iowa City, Iowa, 52246, US)
GOREE, John Arlin (1820 Flanigan Ct, Iowa City, Iowa, 52246, US)
TOOR, Fatima (2045 Dempster Drive, Coralville, Iowa, 52241, US)
BROGDEN, Kim Alan (2133 Oakdale Ridge, Coralville, Iowa, 52241, US)
QUELLHORST, Neil (3734 Forest Gate Dr. NE, Iowa City, Iowa, 52240, US)
Application Number:
US2017/041195
Publication Date:
January 11, 2018
Filing Date:
July 07, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
UNIVERSITY OF IOWA RESEARCH FOUNDATION (112 N Capitol Street, 6 Gilmore HallIowa City, Iowa, 52242, US)
MORIO, Kimberly Ann (3183 Stillwater Cove NE, Solon, Iowa, 52333, US)
DRAKE, David Ray (911 Talwrn Court, Iowa City, Iowa, 52246, US)
GOREE, John Arlin (1820 Flanigan Ct, Iowa City, Iowa, 52246, US)
TOOR, Fatima (2045 Dempster Drive, Coralville, Iowa, 52241, US)
BROGDEN, Kim Alan (2133 Oakdale Ridge, Coralville, Iowa, 52241, US)
QUELLHORST, Neil (3734 Forest Gate Dr. NE, Iowa City, Iowa, 52240, US)
International Classes:
A61C5/40
Domestic Patent References:
WO2013103794A12013-07-11
WO1995008962A11995-04-06
WO2013151585A12013-10-10
Foreign References:
US20100330523A12010-12-30
Other References:
None
Attorney, Agent or Firm:
PERDOK, Monique M. et al. (P.O. Box 2938, Minneapolis, Minnesota, 55402, US)
Download PDF:
Claims:
THE CLAIMED INVENTION IS:

1. A light based dental treatment device comprising:

a handle:

an instrument shaft extending from the handle, an instrument profile of the instrument shaft is configured for delivery into a cavity or passage of a tooth, the instalment shaft includes:

at least one light delivery port along the instrument shaft, and a reflective inner wall surrounding a light passage, the light passage extends through the instrument shaft to the at least one light delivery port; and

a light source in communication with the at least one light delivery port though the light passage, the light source is configured to generate light in one or more wavelengths, and the reflective inner wall is configured to reflect light from the light source to the at least one light delivery port,

2. The light based dental treatment device of claim I, wherein the light source includes a unitary light source configured to generate light in two or more wavelengths.

3. The light based dental treatment device of claim 2 comprising a multiplexer module coupled with the light source, the multiplexer is configured to operate the light source to generate light in two or more wavelengths.

4. The light based dental treatment device of claim 1 , wherein the light is configured to generate light between around 200 to 280 nanometers and between around 315 to 400 nanometers.

5. The light based dental treatment device of claim 1 , wherein the light source is configured to generate light having a wavelength between 200 and 450 nanometers.

6. The light based dental treatment device of claim 1, wherein the light source consists of one or more of an LED, laser diode, laser or quantum cascade laser.

7. The light based dental treatment device of claim 1, wherein the light source includes a first wavelength LED configured to deliver light at a first wavelength and a second wavelength LED configured to delivery light at a second wavelength different from the first wavelength.

8. The light based dental treatment device of claim 7, wherein at least one of the first and second wave lengths consist of at least one of a disinfection wavelength, regeneration wavelength, revascularization wavelength, inflammation reduction wavelength or pain reduction wavelength,

9. The light based dental treatment device of claim 1 , wherein the reflective inner wall extends a proximal end portion of the instrument shaft to the at least one light delivery port.

10. The light based dental treatment device of claim 1, wherein the instrument shaft includes at least one bend, and the reflective inner wall delivers light through the bend.

11. The light based dental treatment device of claim 10, wherein the bend includes a curve shape in the instrument shaft.

12. The light based dental treatment device of claim 10, wherein the bend includes an angle in the instrument shaft relative to a light axis of the light source.

13. The light based dental treatment device of claim 1, wherein the at least one light delivery port is at a distal end portion of the instrument shaft.

4. The light based dental treatment device of claim 1, wherein the at least one light delivery port includes a plurality of light delivery ports.

15. The light based dental treatment device of claim 1, wherein the at least one light delivery port includes a plurality of light delivery ports spaced along the instrument shaft.

16. The light based dental treatment device of claim 1, wherein the reflective inner wall has a reflectivity of at least 11 percent or greater.

17. The light based dental treatment device of claim 1 , wherein the reflective inner wall has a reflectivity of at least 35 percent or greater. 8. The light based dental treatment device of claim 1, wherein the reflective inner wall has a reflectivity of at least 90 percent or greater.

19. The light based dental treatment device of claim 1, wherein the instrument shaft includes at least one of medical grade aluminum, medical grade stainless steel or a nickel titanium alloy.

20. The light based dental treatment device of claim 1 comprising a lens interposed between the light source and the instrument shaft.

21. The light based dental treatment device of claim 20, wherein the lens includes a focal length proximate to the lens spacing from a proximal opening of the light passage.

22. The light based dental treatment device of claim 20, wherein the lens includes a refractive index of around 1.5, a focal length of 10 millimeters, and a center thickness of 2.6 millimeters.

23. The light based dental treatment device of claim 1, wherein the light source is spaced from the light passage around 0 to 20 millimeters.

24. The light based dental treatment device of claim 1 , wherein the instrument shaft is at least 15 millimeters in length.

25. A method for treating a tooth comprising:

positioning an instrument shaft within a passage or cavity in the tooth, the instalment shaft includes at least one light delivery port proximate a distal end portion of the instrument shaft within the passage or cavity; and

treating features within the passage or cavity with ultraviolet light from the at least one light delivery port, treating features includes:

conveying ultraviolet light through a light passage of the instrument to the at least one light delivery port within the passage or cavity, conveying ultraviolet light includes reflecting ultraviolet light along a reflective inner wall of the instrument shaft, and

delivering the ultraviolet light to the features within the passage or cavity through the light delivery port.

26. The method of claim 25, wherein delivering the ultraviolet light to the passage or cavity of the tooth includes triggering cell death in resident microorganisms.

27. The method of claim 25 comprising irrigating the passage or cavity with a chemical solution including an antimicrobial agent before treating the passage or cavity with ultraviolet light.

28. The method of claim 27, wherein delivering the ultraviolet light to the root canal includes:

exciting the molecules of the chemical solution within the root canal to generate free radicals from the chemical solution, and

triggering cell death in resident bacteria in the irrigated zone with the generated free radicals.

SO

29. The method of claim 25 comprising generating ultraviolet light within a handle coupled with the instrument shaft, the handle configured for positioning within the oral cavity.

30. The method of claim 25 comprising generating ultraviolet light remotely from the instrument shaft and a handle coupled with the instrument shaft and transmitting the generated ultraviolet light through a fiber optic cable to the light delivery port.

31. The method of claim 25 comprising mechanically debriding the passage or cavity with an endodontic file having a file profile corresponding to an instrument profile of the instrument shaft.

32. The method of claim 25, wherein a depth stop is movabiy coupled along the instrument shaft, and positioning of the instrument shaft within the passage or cavity includes;

spacing the depth stop from the light delivery port according to a specified plunge depth of the light delivery port into the passage or cavity, and

positioning the light delivery port within the passage or cavity at the specified plunge depth according to the depth stop.

33. The method of claim 25, wherein treating features with ultraviolet light includes treating features with ultraviolet light having a wavelength from 200 to 450 nanometers.

34. The method of claim 25, wherein treating features with ultraviolet light includes:

treating features with ultraviolet light having a wavelength from around 200 to 280 nanometers for killing microorganisms in the passage or cavity, and

treating features with ultraviolet light having a wavelength from around 280 to 400 nanometers to promote one or more of tissue regeneration, revascularization, inflammation reduction or pain reduction,

35. The method of claim 25, wherein treating features with ultraviolet light includes treating features with ultraviolet light having a wavelength from around 280 to 315 nanometers to promote one or more of tissue regeneration or revascularization.

36. The method of claim 25, wherein treating features with ultraviolet light includes treating features with ultraviolet light having a wavelength from around 315 to 400 nanometers to promote one or more of inflammation reduction or pain reduction.

37. The method of claim 25 comprising focusing ultraviolet light through a lens interposed between a light source and the light passage.

38. A light based medical device comprising:

a handle;

an instrument shaft extends from the handle, an instrument profile of the instrument shaft configured for delivery into one or more of an anatomical lumen, passage or cavity, the instrument shaft includes:

a light delivery port at a distal end portion of the instrument shaft, and

a reflective inner wall surrounding a light passage, the light passage extends through the instrument shaft to the light delivery port; and

a light source in communication with the light delivery port though the light passage, the light source is configured to generate light in one or more wavelengths, and the reflective inner wall is configured to reflect light from the light source to the at least one light delivery port.

39. The medical device of claim 38, wherein the light source includes a light source configured to deliver light at multiple wavelengths.

40. The medical device of claim 38, wherein the light source is configured to generate ultraviolet light between around 200 to 400 nanometers.

41 . The medical device of claim 38, wherein the light source consists of at least one of an LED, laser diode, laser or quantum cascade laser.

42. The medical device of claim 38, wherein the reflective inner wall includes a reflectivity of 35 percent or greater.

43. The medical device of claim 38 comprising a lens interposed between the light source and the light passage.

44. A method for light based treatment comprising:

positioning an instrument shaft within one or more of an anatomical lumen, passage or cavity, the instrument shaft includes at least one light delivery port and a reflective inner wall surrounding a light passage extending through the instrument shaft to the at least one light delivery port; and

treating a portion of the anatomy within at least one of the anatomical lumen, passage or cavity with light from the at least one light delivery port, treating including:

conveying light through the light passage to the at least one light delivery port according to reflection along the reflective inner wall, and delivering the light to the portion of the anatomy through the at least one light delivery port.

45. The method of claim 44, wherein the at least one light source includes a first light source and a second light source, and generating light includes:

generating a first wavelength light with the first light source, and generating a second wavelength light with the second light source.

S3

46. A method for decreasing microbial growth in a void within a mammalian body comprising:

inserting a tube having a distal opening, a proximal opening, an exterior surface, an interior surface, and a shaft length of at least 15 mm into the void; and

exposing the void within the mammalian body to light having a wavelength of from about 200 nanometers to about 450 nanometers for at least 15 seconds, wherein the light is commuted through the interior of the tube.

47. The method according to claim 46, wherein the void is a cavity within the oral cavity.

48. The method according to claim 46, wherein the void is an abscess.

49. The method according to claim 48, wherein the abscess is an

oropharyngeal abscess or a retropharyngeal abscess.

50. A method according to claim 46, wherein the interior surface has a reflectivity equal to or greater than 35 percent.

51 . A method according claim 46, wherein the tube is made from aluminum or stainless steel.

52. The method according to claim 46, wherein the void includes a void within an oral cavity formed during a procedure selected from a root canal, an implant or a bone graft.

53. The method of claim 46, wherein exposing the void comprises a first exposure at a wavelength of light from about 225 to about 275 nanometers, and a second exposure at a wavelength of light from about 400 to about 450 nanometers.

54. A method of decreasing microbial growth in a cavity within the oral cavity comprising:

flushing a cavity in the oral cavity with an antimicrobial solution; and exposing the cavity in the oral cavity to light having a wavelength of from about 200 nanometers to about 450 nanometers.

55. The method according to claim 54, wherein the light is delivered through a tube having a shaft length of at least 15 mm.

56. The method according to claim 54, comprising allowing the

antimicrobial solution to stay in contact with the cavity in the oral cavity for at least 30 seconds.

57. The method according to claim 54, wherein exposing the cavity includes exposing the cavity to the light for at least 15 seconds.

58. A device for delivering light having a wavelength from about 200 nanometers to about 450 nanometers to a cavity in the oral cavity comprising: a light source;

a tube having a shaft length of at least 15 millimeteSrs and having a first distal opening and a proximal second opening, wherein the light source is from about 0 mm to about 20 mm from the proximal opening.

59. The device according to claim 58 comprising a lens in between the light source and the proximal opening.

60. The device according to claim 58, wherein the tube has an interior surface and the interior surface has a reflectivity such that there is at least 1 1 percent transmission of light at the distal opening relative to an initial quantity of light at the proximal opening.

61. The device according to claim 58, wherein the tube is made from aluminum or stainless steel.

Description:
LIGHT BASED DENTAL TREATMENT DEVICE

COPYRIGHT NOTICE A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimi le reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever. The following notice applies to the software and data as described below and in the drawings that form a part of this document: Copyright University of Iowa Research Foundation, Iowa City, Iowa. All Rights Reserved.

TECHNICAL FIELD

This document pertains generally, but not by way of limitation, to treatments and instruments for treating microorganisms within and around the oral cavity and within and around anatomical passages or cavities.

BACKGROUND

Endodontic treatment includes, in part, bacterial disinfection of a root- canal system and the prevention of re-infection. In some examples, endodontic treatment involves chemical and mechanical debridement of the canal space for disinfection. Chemical irrigation infiltrates the root-canal system, and disinfects or dissolves tissue and removes necrotic debris from the canal wall.

For instance, irrigation of the canal system after mechanical formation of a passage removes tissue remnants, microorganisms and dentin chips by a continual flushing of the canal space. A combination of irrigants in sequence is optionally used for treatment. On example of an irrigant includes sodium hypochlorite (NaOCl) for its efficacy for disinfection and ability to dissolve organic material. In other examples, sodium hypochlorite is used in

combination with Ethylenediaminetetraacetic acid (EDTA). The addition of chlorhexidine (CHX) as an irrigant is also used in some example because of its antimicrobial activity, for instance against Enterococcus faecalis.

i OVERVIEW

The present inventors have recognized, among other things, that a problem to be solved can include enhancing the disinfection of the canal system (or other anatomical passage or cavity). The instrumentation of the canal space is a step in the process of cleaning and disinfection. Mechanical instruments have limitations due to the complexity of the canal systems (e.g., lateral canals, fins and crevices along canal walls or the like). This has been demonstrated by microcomputed tomography (CT) scanning which showed large areas of the root canal walls that were left untouched by instruments. The instruments have limited ability to navigate the canal space and reach tissue remnants,

microorganisms and dentin chips retained in these tortuous spaces. Accordingly, the clinician is reliant on the chemical irrigation of the canal system to disinfect the untouched canal features and achieve a successful outcome. However, chemical irrigants are also subject to the tomography of the canal (e.g., lateral canal passages, crevices, fins or the like) and in some examples fail to disinfect features of the canal. For instance, the flushed chemical irrigants fail to adequately reach tortuously hidden features along or extending from the canal. Additionally, remnant tissues, microorganisms or the like are, in some examples, suspended in or concealed by biofilms, collections of proteins, carbohydrates or the like that further complicate access by irrigants.

The present subject matter can help provide a solution to this problem, such as with a light based dental treatment device configured to broadcast one or more wavelengths of light within a cavity or passage of the tooth to achieve one or more therapeutic benefits (e.g., disinfection, tissue regeneration, revascularize tissue, reduce inflammation or pain or the like). The light based dental treatment device includes a handle and instrument shaft extending from the handle. The handle and instalment shaft, in one example, have a profile corresponding to a dental file used in some examples for mechanical debridement of a canal The corresponding profi le leverages the familiarity of the clinician (with a file) and facilitates access to a passage in the tooth through manipulation and application of the device within the oral cavity.

The light based dental treatment device further includes at least one light delivery port along the instrument shaft. For instance, the device includes a plurality of light delivery ports configured to broadcast light in one or more directions including laterally, distally or the like and accordingly reach complex features found in and around the passage. The instrument shaft further includes a reflective inner wall surrounding a light passage that extends through the shaft to the at least one delivery port. A light source (e.g., an LED, laser diode, laser, quantum cascade laser or the like) is in communication with the light passage and is configured to broadcast light at one or more wavelengths configuration to achieve therapeutic benefits including, but not limited to, disinfection, tissue regeneration, revascularization of tissue, reduction of inflammation or pain, or the like. The reflective inner wall conveys light through the light passage to the at least one delivery port for delivery to the cavity or passage of the tooth.

Optionally, the instrument shaft is bent, including one or more of curved, angled or the like (e.g., by the clinician or at construction of the device) to facilitate the delivery of the instrument shaft into difficult to access passages or cavities. The reflective inner wall facilitates the delivery of light through the one or more light delivery ports even when bent.

The delivered light is broadcast into the cavity or passage and reaches the specified targets (tissues, microorganisms or the like) even in difficult to reach locations (lateral canals, fins and crevices along canal wails, and within biofilms, collections of proteins, carbohydrates or the like). Additionally , manipulation of the device including translation into and out of the tooth, rotation or the like increases the coverage of the one or more light delivery ports by moving the ports across arcs, along linear routes or the like. Further, by using one or more wavelengths of light a variety of microorganisms are killed to enhance the disinfection of the cavity or passage in the tooth.

This overview is intended to provide an overview of subject matter of the present patent application. It is not intended to provide an exclusive or exhaustive explanation of the disclosure. The detailed description is included to provide further information about the present patent application.

BRIEF DESCRIPTION OF DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

Figure 1 is a side view of one example of a light based dental treatment device.

Figure 2 is a schematic view of the light based dental treatment device of

Figure 1 positioned with a root canal.

Figure 3 A is a schematic view of one example of an instrument shaft of the device shown in Figure 1.

Figure 3B is a schematic view of another example of an instrument shaft of the device shown in Figure 1 .

Figure 4 is a schematic diagram of the light based dental treatment device of Figure 1 including an instrument shaft having a reflective inner wall.

Figures 5A-D are plots showing the conveying of light through an instrument shaft of the light based dental treatment device.

Figures 6A-C are example light based dental treatment devices in bent

configurations.

Figure 7 is a schematic example of a wavelength multiplexer.

Figure 8 is a plot showing one example of multiple wavelengths of light generated with the example light based dental treatment devices. Figure 9 is a schematic view of another example of a light based dental treatment device including a lens interposed between a light source and a light passage.

Figure 10 is a block diagram showing one example of a method for treating a tooth.

DETAILED DESCRIPTION

Figure 1 shows one example of a light based dental instmment 100. As shown, the light based dental instrument includes a handle 102 and an iiistrament shaft 104 extending from a proximal end portion 106 (proximate to the handle 102) to a distal end portion 108. As will be described herein, the light based dental instrument 100 is configured to provide one or more wavelengths of light energy, for instance, to cavities, passages or the like of one or more dental features, such as teeth. In other examples, the light based dental instrument 100 (and 900) also includes medical devices configured for navigation and delivery through one or more passages, cavities, voids or the like of the anatomy. For instance, the instruments described herein (e.g., instruments 100, 900) are used in a variety of therapeutic procedures including, but not limited to, dental procedures such as root canals, catheter based therapies including vascular and digestive procedures, surgical procedures, and introduction or guiding of other instruments (e.g., the components described, such as the light passages, ports, reflective inner walls and the like are provided around a delivery or guide lumen of an introducer or guide catheter).

Referring again to Figure 1 , the light based dental instrument 100 includes one or more light sources 1 10. In the example shown in Figure 1 , the light source 1 10 is provided in one or more of the handle 102 or at a remote location relative to the handle 102 and the instrument shaft 104 (e.g., as shown proximal to the handle 102 and in broken lines). Where the light source 1 10 is remote relative to the remainder of the light based dental instrument 100 one or more cables, such as fiber optic cables or the like, are provided to transmit light generated by the light source 1 10 to the light based dental instrument 100, for instance along a light passage 1 12, to one or more light delivery ports 1 16 as shown in this example proximate to the distal end portion 108.

In other examples, the light source 1 10 is provided within the handle 102 and proximate to the instrument shaft 104 (optionally the light source 1 10 is positioned within or is included with the instrument shaft 104 in another example). In each of these configurations, the light source 1 10 generates one or more wa velengths of light that are transmitted through the light passage 1 12 extending within at least the instrument shaft 104.

The one or more wavelengths of light are transmitted through the instrument shaft 104 to one or more light delivery ports 1 16. In the example shown in Figure 1, a plurality of light delivery ports 1 16 (exaggerated for illustration purposes) are provided proximate to the distal end portion 108. In other examples, the light delivery ports 116 are provided in a distributed fashion along the length of the instrument shaft 104, for instance from the distal end portion 108 toward the proximal end portion 106, continuously between the distal end portion 108 and the proximal end portion 106 or at one or more locations along the instrument shaft 104 between the proximal end portion 106 and the distal end portion 108.

As previously described and shown, for instance, in Figure 1 , the light source 110 includes, in various examples, a light source provided in one or more of the handle 102 in a position remote to the handle (e.g., as shown with the second light source 1 10 provided in broken lines) or within or proximate to the instrument shaft 104. The light source 1 10 is configured, in one example, to provide one or more wavelengths of light having one or more corresponding therapeutic benefits to a patient. The light source 110 includes one or more of a variety of light sources including, but not limited to, a light emitting diode (LED), a laser diode, laser, quantum cascade laser or the like. In one example, the light source 1 10 includes one or more light sources configured to provide one or more wavelengths of light. For instance, the light source 1 10, in one example, is configured to provide a plurality of wavelengths of light to provide corresponding different therapeutic benefits including, but not limited to, disinfection, tissue regeneration, revascularization of tissue, inflammation reduction, pain reduction or the like.

As described herein, the light source 1 10 includes one or more light sources configured to provide light having wavelengths between one or more of 200 to 450 nanometers, 225 to 350 nanometers, 225 to 300 nanometers or the like. In one example, light within the wavelengths 200 to 450 nanometers corresponds to ultraviolet light configured to provide differing therapeutic benefits. For instance, light having a wavelength of 200 to 280 nanometers is provided by the light based dental instrument to provide microorganism disinfection (e.g., one or more of microbial or bactericidal disinfection). In another example, the range of wavelengths provided by the light source 1 10 for disinfection includes 240 to 245 nanometers. In other examples, the light source 110 is configured to provide light having wavelengths between around 280 to 315 nanometers and thereby configured to provide one or more of tissue regeneration or revascularization of existing tissue. In still other examples, the light source 110 is configured to provide light having wavelengths of between around 3 5 to 400 nanometers to facilitate one or more of the reduction of inflammation or pain in a patient receiving treatm ent by way of the light based dental instrument 100.

As will be described herein, the light source 1 10 optionally includes a single light source 1 0 configured to provide a plurality of wavelengths including one or more of the wavelengths previously described herein. A control system such as a multiplexer system in communication with the light source 1 10 is, in one example, configured to adjust (e.g., modulate) the output of the light source 1 10 to thereby provide the corresponding wavelengths of light (including wavelength ranges) for the various treatment therapies.

Referring again to Figure 1 , as previously described the light based dental instrument 100 includes an instrument shaft 104. In one example, the instrument shaft 104 is configured to have a similar profile to a shaft of a dental file used in a root canal procedure to mechanically debride a cavity or other passage within the affected tooth. As shown in Figure 1 , the handle 102 and the instrument shaft 104, in one example, have a corresponding shape and size (e.g., profile) to a dental file. In the example shown, the instrument shaft 104 has a gentle taper from the distal end portion 108 to a depth stop 1 14 proximate to the proximal end portion 106. In a corresponding fashion, the handle 102 is sized and shaped to provide one or more finger grips, knurling or the like to facilitate manipulation by a dental practitioner such as a dentist, endodontist, orthodontist or the like within the oral cavity of the patient.

The depth stop 114 is optionally included with the light based dental instrument 100 to limit the delivery depth of the instrument shaft 104. The practitioner sets a specified plunge depth of the depth stop 114 along the instrument shaft 104 (or the depth stop 114 is preset at assembly), and the instrument shaft 104 is accordingly limited to that depth when inserted into a passage, cavity or the like.

The instrument shaft 104, in some examples, includes one or more materials. The instrument shaft 104 includes, but is not limited to, aluminum, stainless steel, polymers, composites or the like. The inclusion of one or more plastically deformable materials such as aluminum or stainless steel facilitates the bending of the instrument shaft 104 by the practitioner while performing one or more procedures. For instance, the instrument shaft 104 is bent into one or more bent configurations (angled, curved, crooked or the like) to facilitate the delivery of the instrument shaft 104 into one or more passages, cavities or the like to facilitate the delivery of light, for instance, through the light delivery ports 1 16. Additionally, the bending of the instrument shaft 104 optionally facilitates access to a tooth within the oral cavity (as well as a passage or cavity of the tooth) that is otherwise difficult to reach with a linear instrument. As described herein, the light based dental instrument 100 is configured to maintain delivery of light through the instrument shaft 104 to the one or more light delivery ports 1 16 even in a bended configuration.

As will be described herein, various examples of instrument shafts 104 are provided including one or more instrument shafts having light passages 1 12 configured to transmit light of one or more wavelengths from the proximal end portion 106 to the light delivery ports 1 16, for instance, proximate to the distal end portion 108. For instance, in Figures 3 A and 3B, the instrument shaft 104 optionally includes a light passage 1 12 including a dedicated tube, liner or the like extending from the proximal end portion 106 to a position proximate to the one or more light delivery ports 1 16. In one example, a fiber optic cable is provided within the instrument shaft 104 to facilitate the delivery of light along the instrument shaft 104 to the ports 116,

In another example, the instrument shaft 104 is constructed with a reflective material or includes a reflective material along an inner wal l of the instrument shaft 104. As previously described herein, in one example, the instrument shaft 104 is constructed with, but not limited to, aluminum, stainless steel or the like. Each of these materials has a relatively high reflectivity (35 percent or greater) and thereby facilitates the reflective transmission of light along the instrument shaft 104, for instance, to the light delivery ports 1 16. Further, with bending of the instrument shaft 104 either as constructed or during a procedure, the reflective materials of the instrument shaft 104, such as aluminum or stainless steel, facilitate the delivery of light around bends including curves, angles or the like. In other examples, the instrument shaft 104 includes a reflective coating configured to facilitate or enhance the reflection of light along the instrument shaft 104 to the light delivery ports 1 16. Figure 2 shows one example of a tooth 200 after mechanical removal of material (e.g., enamel, dentin, pulp or the like) to form one or more passages or cavities within the tooth 200. For instance, in the example shown in Figure 2, the tooth 200 includes a root canal 204 bore out along each of the roots 202 and through the upper tooth structure. As further shown in Figure 2, the light based dental instrument 100 is shown in an operative configuration, for instance, with the instalment shaft 104 extending into the tooth 200 and along one of the roots 202. One or more light delivery ports 116 (in this example a plurality) are provided at a variety of locations along the instrument shaft 04. The light delivery ports 116 facilitate the broadcast of light at one or more wavelengths from the instrument shaft 104 and into the root 202 to provide one or more therapeutic effects to features 206 within the roots 202 as well as the remainder of the tooth 200,

In one example, the instrument shaft 104 is manipulated by translation, rotation or the like to accordingly bathe a portion (including the entirety) of the root canal 204 with light delivered from the light delivery ports 1 6. As shown in the example in Figure 2, the light delivery ports 116 are at various locations along the instrument shaft 04 to facilitate the broadcast of light from the instrument shaft 104 in one or more directions and one or more patterns (e.g., light profiles or patterns, broadcast profiles or patterns, or the like).

As also shown in Figure 2, in one example, the tooth 200 includes one or more features 206. The features 206 include, but are not limited to, one or more lateral canals, passages (for instance, extending from a main root canal 204), crevices, fins, biofilms, collections of proteins, carbohydrates or the like. As previously described herein, biofilms, proteins, carbohydrates and the like may hide, conceal or protect one or more microorganisms therein. These features 206 frustrate the removal or killing of microorganisms with one or more or chemical irrigants, mechanical debridement or the like. Light in one or more wavelengths, including wavelengths 200 to 280 nanometers, delivered into these features 206 including canals, passages, crevices, fins, biofilms, proteins, carbohydrates or the like reaches difficult to access microorganisms and kills them. Optionally, light delivered from the instalment 100 cooperates with chemical irrigants to enhance the effectiveness of the irrigants, for instance within the features 206. In the configuration shown in Figure 2, for instance, with the tooth 200 bored out and in the process of disinfection with the light based dental instrument 100, a root canal 204 (one example of a cavity, passage or the like) is formed, in one example, with a dental drill and one or more tools including dental files. The root canal 204 is thereafter mechanically cleaned, for instance, by mechanical debridement with a dental file to remove dental pulp including the nerve, blood vessels or other soft tissue provided within the tooth 200. As further shown, the tooth 200 is optionally irrigated, for instance, with one or more bactericidal irrigants including, but not limited to, one or more of sodium hypochlorite, EDTA, chlorhexidine (CHX) or the like. These irrigants are, in some examples, found to be effective against one or more microorganisms. In the example shown in Figure 2, a surface of the irrigant 208 is shown in the tooth 200 with a broken line and pooled there below. In other examples, the irrigant 208 is flushed into the tooth 200 and aspirated out.

At least a portion of the irrigant 208 remains within the tooth 200, for instance, along one or more of the features 206 provided within the root canal 204, within the main portion of the tooth 200 or the like. In one example, the light based dental instrument 100 is used in combination with the irrigant 208. The provision of light having one or more wavelengths to the irrigant 208, for instance, adjacent to the features 206 generates one or more free radicals including chloride ions or the like configured to readily engage with and break down the one or more features 206 within the tooth 200. Because the irrigant is already present the generation of free radicals with the application of light from the light based dental instrument 100 immediately applies the resulting free radicals to the features 206 and readily breaks down one or more biofiims, proteins, carbohydrates or the like and kills microorganisms otherwise concealed within biofiims, carbohydrates, proteins or the like.

In still other examples, after mechanical debridement (removal of one or more features of the tooth 200 including nerves, blood vessels, tissue or the like) the light based dental instrument 100 is used by itself, for instance, in a configuration shown as in Figure 2 to broadcast light (without an irrigant) into the root canals 204. The disbursed broadcasting of light, for instance, from the one or more light delivery ports 116 (optionally with one or more of rotational or translationai manipulation) distributes one or more wavelengths of light into the root canal 204 and the remainder of the tooth 200 to accordingly interact with one or more of the features 206 (e.g., side canals, irregular features such as fins, biofilms, proteins, carbohydrates or the like). The light by itself interacts with the microorganisms in the passage or cavity (and optionally within features 206) to kill the microorganisms and provide a cleaned tooth 200 ready for one or more dental procedures including filling, crowns or the like.

Figures 3 A and 3B show two schematic configurations of the instrument shaft 104. Referring first to Figure 3 A, one example of an instrument shaft 104 including a light passage 1 12 having a light transmitting element 300 extending there along is provided. The instrument shaft 104 is enlarged to accordingly illustrate the light transmitting element 300 therein. In one example, the light transmitting element 300 includes one or more of a tube, cable or the like such as a fiber optic element extending through the instrument shaft 104, for instance, from the proximal end portion 106 to the distal end portion 08. The light transmitting element 300 at the distal end portion 106 transmits the light into the remainder of the instrument shaft 104. The light from the light passage 1 12 of the light transmitting element 300 is broadcast from the light delivery ports 1 6 in a pattern corresponding to the positioning and profile (e.g., size and shape) of the light delivery ports 1 16. In one example, the one or more light delivery ports 1 16 includes a single port, for instance, provided at the distal tip of the distal end portion 08 and directed di stall y relative to the instrument shaft 104. In other examples, and as previously shown herein, the one or more light delivery ports 1 16 are at one or more locations, for instance, at the distal end portion 108 or along the instrument shaft 104 to accordingly broadcast light delivered by the light transmitting element 300 laterally relative to the instrument shaft 104 and into one or more features such as the features 206 previously shown in Figure 2. The light transmitting element 300 includes, but is not limited to, one or more materials, for instance, stainless steel, aluminum, composites, polymers, glass or the like configured to transmit light along its length, for instance, within the instrument shaft 104 to the one or more light delivery ports 1 16,

Figure 3B shows another example of the instalment shaft 104, coupled with a handle 102, the depth stop 1 14 and other features of the light based dental instrument 100. In the example shown in Figure 3B, the instalment shaft 104 includes a light passage 1 12 formed by a reflective inner wall 302 of the instrument shaft 104. As previously described, the instrument shaft 104 is, in one example, constructed with, but not limited to, one or more materials such as aluminum (having a reflectivity of approximately 90 percent), stainless steel (having a reflectivity of approximately 35 percent), a polymer, composite or the like. Optionally, the reflective inner wall 302 is coated or treated with one or more materials to accordingly enhance the reflectivity of the base material or, in another example, to provide the reflectivity of the reflective inner wall 302, The reflective inner wall 302 facilitates the delivery of light, for instance, from the proximal end portion 06 and a light source 1 0 of the light based dental instrument 100 (shown in Figure 1 ) to the distal end portion 108 as well as the one or more light delivery ports 116 provided along the instrument shaft 04. In the example shown in Figure 3B, a plurality of light delivery ports 1 16 are provided at various locations along the length of the instrument shaft 104 (e.g., longitudinal and circumferential positions). For instance, in the example shown, three separate light delivery ports 116 are provided at various positions proximate to the distal end portion 108. In another example, a plurality of light delivery ports 116 are localized to the distal end portion 108. Optionally, the light delivery ports 116 are distributed between the distal end portion 108 and the proximal end portion 106. In still other examples, the light delivery ports 1 16 are provided at any or a plurality of locations along the instrument shaft 104, for instance, proximate to the proximal end portion 106, proximate to the distal end portion 108 or one or more positions there between.

As previously described herein, in some examples, the instrument shaft

104 is constructed with materials configured to include a bent configuration (e.g., including plastic deformation or one or more bends when formed). In the example shown in Figure 3B, with the reflective inner wail 302, deformation of the instrument shaft 104 does not preclude the delivery of light, for instance, from the proximal end portion 106 and the light source 1 10 along the instrument shaft 104 to the one or more light delivery ports 1 16. Instead, the reflective inner wall 102 of the light passage 112 reflects the generated light there along and accordingly transmits the light from the proximal end portion 106 toward the distal end portion 108 and to any light delivery ports 1 16 provided along the instrument shaft 04, Accordingly, with manufacturing or deformation by a practitioner or clinician into a bent configuration, the light based dental instrument 100 reliably transmits light at one or more wavelengths through the one or more light delivery ports 1 16 to achieve the specified therapeutic benefits.

Figure 4 shows a schematic example of the light based dental instrument 100 including the instalment shaft 104 and one or more light sources 1 10 such as a first component light source 404 and a second component light source 406. The light sources 04, 106 are schematically shown broadcasting light into the instrument shaft 104. The instrument shaft 104 is constructed with one or more materials, coatings or the like to form the reflective inner wall 302 to facilitate the delivery of light. As shown in Figure 4, light rays schematically extend from the proximal end portion 06 toward the distal end portion 108 and the one or more light delivery ports 116 provided thereon.

As further shown in Figure 4 and previously described herein, the light source 1 0, in this example, includes first and second component light sources 404, 406. In one example, the first and second light sources 404, 406 are configured to provide differing wavelengths of light, for instance, disinfecting wavelengths as well as wavelengths configured to regenerate, revascuiarize, reduce inflammation, reduce pain or the like. Each of the component lights shown by way of the light rays 400 and light rays 402 are transmitted through the instrument shaft 104, for instance by its reflective inner wall 302, to the one or more light delivery ports 1 16 provided along the instrument shaft 104. In this example, the light delivery ports 1 16 are localized to the distal end portion 108. In other examples, the light delivery ports 116 (as described herein) are provided along the instrument shaft 104, for instance, between the proximal and distal end portions 106, 108.

Referring again to Figure 4, as shown the light rays 400, 402 are reflected along the reflective inner wall 302, Because the light rays 400, 402 are transmitted by the instrument shaft 104 along the reflective inner wall 302, the light delivery ports 1 16 are optionally provided at any location along the instrument shaft 104 to broadcast the light according to the position of the light delivery ports 116. Stated another way, the reflective inner wall 302 delivers light to all light delivery ports 1 16 that extend into the light passage 112. In contrast, with a tube, cable or the like provided in the instrument shaft 104 the light delivery ports 1 16 are distaily positioned relative to the cable, tube or the like (e.g., adjacent to or downstream from the tube) to receive light delivered from the distal end of the tube.

As previously described, the light source 1 10 shown in Figure 4 includes first and second component light sources 404, 406. Optionally, the first and second component light sources each broadcast a single wavelength of light, for instance, the same wavelength. In another example, the first and second component light sources 404, 406 broadcast differing wavelengths of light (including ranges of wavelengths), for instance, each having differing therapeutic benefits. In one example, the light ray 400 is broadcast at a wavelength such as 200 to 280 nanometers (including one or more wavelengths and a range of wavelengths) configured to disinfect within a passage or cavity (e.g., of the tooth 200 shown in Figure 2). In another example, the second light ray 402 provides one or more various therapeutic benefits including one or more tissue regeneration, tissue revascularization, inflammation reduction, pain reduction or the like. Optionally, each of the first and second component light sources 404, 406 are configured to provide one or more wavelengths of light, for instance, each of the first and second component light sources 404, 406 are, in one example, each provided with multiple component light elements, multiplexers or the like configured to faci litate the delivery of multiple wavelengths from each of the component light sources 404, 406. Accordingly, the light based dental instrument 100 including one or more component lights 404, 406 is, in some examples, configured to provide two, three, four or even more therapeutic benefits by way of variation of the wavelength generated by each of the component light sources 404, 406. Optionally, the light sources 404, 406 are configured to broadcast differing wavelengths of light including ranges of wavelengths including, but not limited to, 200 to 450 nanometers, 225 to 350 nanometers, 225 to 300 nanometers or the like.

Referring now to Figures 5 A-D, a number of plots are provided showing light rays delivered down a schematic instrument shaft 04. In each of the configurations shown in Figures 5 A-D, the instrument shaft 104 is shaped in a different manner, for instance, into one or more bent or straight configurations. Referring first to Figure 5 A, the schematic instrument shaft 104 is shown extending from a proximal end portion 106 to a distal end portion 108. The instrument shaft 104 is further shown in an initial configuration 502, for instance, a straight configuration aligned with or coincident with a light axis 500 of a light source (such as the light sources described herein).

In Figure 5B, the same instrument shaft 104 as in Figure 5 A is shown in a first bent configuration 504. For instance, the instrument shaft is bent at an angle of 10 degrees relative to the light axis 500 and the initial configuration 502 shown in Figure 5 A. The instrument shaft 104 is bent and accordingly positions the distal end portion 108 at a bent or off axis location. As shown in the plot, the light rays 503 are delivered along the instrument shaft 104 from the proximal end portion 106 to the distal end portion 108 in a manner similar to the light rays 501 shown in the plot provided in Figure 5 A.

Referring now to Figure 5C, the instrument shaft 104 is shown again in a second bent configuration 506. In this example, the instrument shaft 104 is at an angle of approximately 20 degrees relative to the initial configuration 502 or 20 degrees relative to the light axis 500. In this example, the light rays 505 are transmitted along the instrument shaft 104 and reflected along the reflective inner wall (e.g., the reflective inner wall 302 shown in Figures 3B, 4) from the proximal end portion 106 toward the distal end portion 108.

As further shown in Figure 5D, the instrument shaft 104 is formed into a third bent configuration 508 having a more extreme bend relative to the configurations shown in Figures 5B and 5C. In this example, the instrument shaft 104 is provided at around 30 degrees relative to the light axis 500 (e.g., horizontal). As shown, the light rays 507 are successfully transmitted from the proximal end portion 106 to the distal end portion 08. Accordingly, any light delivery ports provided along the instrument shaft 104, for instance, from the proximal end portion 106 toward the distal end portion 108 receive light delivered from the light source 110 along the light axis 500 even with the instrument shaft 104 in bent configurations including, but not limited to those shown in Figures 5B-D.

IS Figures 6A-C show the light based dental instrument 100 in one or more bent configurations. For instance, Figures 6A and 6B show the light based dental instrument 100 including, for instance, the instalment shaft 104 with a first bend 600 and a second bend 602, respectively, having a tighter radius than the bend 600 shown in Figure 6 A. As further shown in each of Figures 6A and 6B, the light based dental instrument 100 delivers a light pattern 606 through one or more light delivery ports 116 provided proximate to the distal end portion 108. As shown, for instance, in Figures 6 A and 6B, the direction of the light pattern 606 is changed relative to the axis of the instrument shaft 104 with bending of the instrument shaft 104. With the extreme curvature provided by the bend 602, for instance, the light pattern 606 is, in one example, broadcast in a lateral manner, for instance, extending away from the distal end portion 108 at an angle less than 90 degrees relative to the handle 02 (and a light source 1 10 provided therein). The remainder of the light pattern 606 is spread relative to the distal end portion 108, for instance in 90 degree sweeps to either side of the initial direction from the distal end portion 08.

Figure 6C shows another example of a bend 604, in this example, providing a relatively sharp angle, corner or the like provided at a position along the instrument shaft 104. In this example light is delivered from the proximal end portion 106 through the instrument shaft 104 into the distal end portion 108, As previously shown, for instance, in the plots provided in 5 A-D, light rays are delivered through the bend 604, for instance, by the reflective inner wall 302 to the distal end portion 108 for eventual distribution at the one or more light delivery ports 116 to form the light pattern 606. Optionally, the instrument shaft 104 is bent over a range of angles while still effectively transmitting light to the one or more light delivery ports 1 16. The range of angles includes less than 90 degrees, 50 degrees or less, 40 degrees or less, 10 degrees or less, zero (0) degrees raight) or the like.

and 6C (as well as the plots provided in Figures 5A-D) are optionally formed the light based dental instrument 100 either during construction or by the clinician, for instance, during a procedure. That is to say, the clinician when accessing one or more of tortuous passages, difficult to reach locations or the like bends the instalment shaft 104 into a desired configuration such as the configuration shown in Figures 6A-C. The clinician then uses the modified (bent) instrument 100 while also having confidence that light is successfully delivered through the light delivery ports 116 to achieve one of more therapeutic benefits.

As described herein, in one or more examples, the light source 1 10 is configured to provide light through the light passage 112 to the one or more light delivery ports 116 at one or more wavelengths for one or more corresponding therapies including, but not limited to, disinfection, regeneration,

revascularization, pain reduction, inflammation reduction or the like. One example of a unitary light source 110 with a composite output (e.g., deli vered light having two or more wavelengths, including ranges of wavelengths) is shown in Figure 7. In the example shown, a controller 700 (e.g., multiplexer or the like) is coupled with the light source 1 10. The controller 700 operates the light source 110 according to a specified algorithm, module, circuit or the like to generate light at the specified wavelengths (e.g., for specified application intervals, intensity and the like) corresponding to changes in a base signal. The example controller 700 shown in Figure 7 includes a multiplexing arrangement of an adder circuit having at least two triggers, for instance a negative polarity trigger 702 and a positive polarity trigger 704. A bi-directional quantum cascade laser (QCL) is the example light source 110 coupled with the controller 700. In other examples, another light source, such as a multi-wavelength capable LED or laser diode is coupled with the controller 700.

The light source 110 in combination with the controller 700 generates light having example wavelengths of around 200 to 280 nanometers (including 240 to 245 nm) for disinfection. In another example, the light source 110 of Figure 7 generates light having wavelengths of around 280 to 3 1 5 nanometers to promote one or more of (wounded) tissue regeneration or revascularization. In still another example, the light source 1 10 of Figure 7 generates light having wavelengths of around 315 to 400 nanometers, to affect cell signaling and promote one or more of inflammation reduction or pain reduction.

In the plot of the light output 800 shown in Figure 8, the generated light (e.g., modulated with the controller 700) is shown with two differing wavelengths 802, 804 that are staggered in time. In one example, the two wavelengths 802, 804 provide different therapeutic benefits including, but not limited to, disinfection, tissue regeneration, revascularization, pain reduction, inflammation reduction or the like, as described herein. In another example, the two wavelengths 802, 804 provide the same therapeutic benefit, such as disinfection, but provide disinfecting light at two wavelengths to affect (e.g., kill) differing microorganisms. While Figures 7 and 8 illustrate a controller 700 and light output 800, in other examples, the controller 700 and resulting plot 800 provide one or more wavelengths including ranges of wavelengths (e.g., spectrums) from 200 to 450 nanometers, 200 to 280 nanometers, 280 to 315 nanometers, 3 5 to 400 nanometers or the like.

Figure 9 shows another example of a light based dental instalment 900. In this example, the instrument 900 includes a lens 920 interposed between a light source 904 and an instalment shaft 902, for instance, a proximal end portion 910 of the shaft 902 and a connecting hub 903. As shown in Figure 9, the lens 920 interposed between the instrument shaft 902 and the light source 904 focuses light from the light source 904 toward the instrument shaft 902. Accordingly, the lens 920, in one example, directs additional light into the instrument shaft 902 to facilitate the delivery of increased light (e.g., higher intensity) at the one or more light delivery ports 916. In some examples, increased light increases the effectiveness of the instrument 900 with regard to one or more therapeutic benefits, decreases treatment time or the like.

The light based dental instrument 900 is, in one example, similar to the previously described light based dental instrument 100 shown in the previous figures and described herein. For instance, the instalment 900 includes an instrument shaft 902 optionally coupled with a handle such as the handle 102 shown in Figure . In the example shown in Figure 9, the instrument shaft 902 includes a reflective inner wall 908 extending from the proximal end portion 910 to the distal end portion 912, In this example, one or more light delivery ports 916 are provided proximate to the distal end portion 912. As with other examples, the light delivery ports 916 are optionally provided at one or more locations along the instalment shaft 902, for instance, between the proximal and distal end portions 910, 912. As shown in Figure 9, one or more light rays generated by the light source 904 are passed through the lens 920, focused by the lens 920 and directed into the instrument shaft 902. The light rays are directed along the reflective inner wall 908 within the light passage 914 to the light delivery ports 916. In another example, the instrument shaft 902 includes one or more of a tube, cable, fiber optic cable or the like provided within the instrument shaft 902 (as shown in Figure 3 A) and configured to deliver light from the proximal end portion 910 to the light delivery ports 916 proximate to the distal end portion 912.

Referring now to the light source 904 and the lens 920, in one example, these features are provided in a handle such as the handle 102 previously shown and described in Figure 1. In another example, the light source 904 and the lens 920 are optionally provided at a location remote relative to the handle 102 and the instrument shaft 902. In this example, light generated by the light source 904 is focused by the lens 920 and directed into a tube, cable, fiber optic cable or the like for transmission to the instrument shaft 902.

In another configuration and as shown in Figure 9, the light based dental instrument 900 includes the light source 904 and the lens 920 proximate to the instrument shaft 902, For instance, each of the light source 904 and the lens 920 are provided within the handle 102. As further shown in Figure 9, the light source 904 is spaced from the lens 920 according to a source-lens spacing 9 8, Similarly, the lens 920 is spaced from the instrument shaft 902 (and the hub 903) by a lens-shaft spacing 922. Optionally, each of the source-lens spacing 918 and lens-shaft spacing 922 are selected according to specified features of the lens 920, light source 904, instrument shaft 902 and light delivery output specified for the light based dental instrument 900. In one example, the lens 920 is spaced from the instrument shaft 902 (an orifi ce of the instrument shaft 902 proximate to the proximal end portion 910) according to the focal length of the lens 920. For instance, the lens-shaft spacing 922 corresponds (e.g., matches or substantially matches) the lens 920 focal length to direct all or nearly all of the focused light into the shaft 902. In another example, the lens-shaft spacing 922 is less than the focal length to bathe the area of the instrument 900 around the instrument shaft 902 with high intensity light while minimizing misalignment of the lens with the instrument shaft 902. In another example, the light source 904 is spaced from the lens 920 (e.g., corresponding to the source-lens spacing 918) to facilitate the delivery of the generated light from the light source 904 to the lens 920 and focusing of that light according to the lens-shaft spacing 922. For instance, where the light source 904 generates light in a conical pattern, in one example, the light source 904 is positioned in proximity to the lens 920 to facilitate the interception of the conical light from the light source 904 at the lens 920 for focusing. Although the configuration shown in Figure 9 spaces each of the light source 904 and the lens 920 from other components of the light based dental instrument 900 (e.g., the source-lens spacing 918 and the lens-shaft spacing 922) these spacings also include proximate spacing as well, such as a spacing of zero millimeters or the like. For instance, in one example, the light source 904 is positioned in immediate proximity to the lens 920 and accordingly the source-lens spacing 918 is zero. Similarly, the lens 920, in another example, is positioned proximate to the proximal end portion 910 of the instrument shaft 902 and the hub 903 (e.g., with the lens-shaft spacing 922 of zero millimeters).

The lens 920 includes a variety of differing lens configurations. One example lens 920 configuration includes, but is not limited to, a plano-convex lens having a focal length of approximately ten millimeters, a center thickness of 2.6 millimeters and a refractive index of 1.5168. Optionally, the lens 920 has a reflectivity of 4 percent. The lens 920, in another example, includes a plurality of lenses, for instance, provided in series to accordingly vary the focusing and delivery of light to the instrument shaft 902. Optionally, the lens 920, including a plurality of lenses, is fixed within a feature such as the handle 102. Fixing of the lens 920 (including one or more lenses) in the handle 102 facilitates the static maintenance of the source-lens spacing 918 and the lens-shaft spacing 922 to fix the focusing of light into the instrument shaft 902 and thereby ensure a consistent delivery of a specified intensity of one or more wavelengths of light through the light delivery ports 916. In another example, the handle 102 or other component associated with the light based dental instrument 900 (for instance, upstream of the handle 02 such as along a fiber optic cable or the like) includes one or more features facilitated to vary the source-lens spacing 918 and lens- shaft spacing 922 (as well as the spacing between multiple component lenses) to accordingly facilitate a change in the intensity of the delivered light into the instrument shaft 902,

Referring again to Figure 9, in at least one example configuration, the lens 920 is positioned with a lens-shaft spacing 922 relative to the instrument shaft 902 of ten millimeters. In this example, the lens 920 is a plano-convex lens having a focal length often millimeters (corresponding to the lens-shaft spacing 922). The light source 904 is spaced according to a source-lens spacing 918 of five millimeters relative to the lens 920. The instrument shaft 902 is constructed with, but not limited to, one or more of the materials or composite materials described herein including, but not limited to, one or more of aluminum, stainless steel, glass, composites, plastics and optionally includes a reflective coating along the interior of the instrument shaft 902. In this configuration (as well as in other configurations) the light source 904, the lens 920 and the reflective inner wall 908 of the light based dental instrument 900 cooperate to focus and deliver light of one or more wavelengths generated by the light source 904 to one or more light delivery ports 916 provided along the instrument shaft 902. As previously described, the source-lens spacing 918 and the lens-shaft spacing 922 are varied in other configurations and, for instance, may position the lens 920 immediately proximate to the instrument shaft 902, for instance, abutting the instrument shaft 902. In still other examples, the instrument shaft 902 is varied with regard to its construction relative to the lens 920 and the light source 904. For instance, the instrument shaft 902 has different lengths, diameters (relative to the light passage 914) or the like to facilitate the delivery of additional light, for instance, to the light delivery port 9 6. For instance, in a number of examples provided herein below, the instalment shaft is varied from an overall length of 15 millimeters to 35 millimeters while having a diameter varying between 0.25 millimeters, 0.5 millimeters, 1.5 millimeters, 2.38 millimeters, 3.175 millimeters, or the like. As provided herein below, variation of the diameter of the instrument shaft 902 while the lens 920 and light source 904 remain static accordingly changes the intensity of the light delivered from the light based dental instrument 900. For instance, when modeled, the light based dental instrument 900 having a variety of instrument shaft 902 lengths and diameters varies its light output from approximately five model light rays to approximately 68 model light rays (relative to 100 base rays generated at the light source 904), Variations of intensity are optionally used to increase the effectiveness of therapies (e.g., enhance disinfection, regeneration, inflammation reduction or other benefits described herein), decrease treatment time or the like.

Figure 10 shows one example of a method 1000 for treating a tooth, such as the tooth 200 shown in Figure 2. In describing the method 1000, reference is made to one or more components, features, functions and steps previously described herein. Where convenient, reference is made to the components, features, steps or the like with reference numerals. Reference numerals provided are exemplary and are not exclusive, for instance, components, features, functions, steps or the like described in the method 1000 include, but are not limited to, the corresponding numbered elements provided herein, other corresponding features herein (both numbered and unnumbered) as well as their equivalents.

At 1002, the method 1000 includes positioning an instrument, for instance, the instrument shaft 104 within a passage or cavity of the tooth 200. As shown, for instance, in Figure 2, the instrument shaft 104 is positioned within a root canal 204 of the tooth 200. The instrument shaft 104 includes one or more light delivery ports 116 provided along the instrument shaft 104, for instance, proximate to the distal end portion 108 of the instrument shaft 104 within the passage or cavity (e.g., within the root canal 204). In another example, as described herein, the one or more light delivery ports 1 16 are provided in a spaced fashion along the instrument shaft 104, for instance, between the distal end portion 108 and the proximal end portion 106.

At 1004, the method 1000 includes treating features within the passage or cavity with one or more wavelengths of light, including ultraviolet light, from the light delivery port 116. As described herein, the one or more wavelengths of light, in one example, include light having wavelengths between 200 and 450 nanometers configured to provide one or more therapeutic benefits within the tooth 200 including, but not limited to, one or more of disinfection,

revascularization or regeneration of tissues therein, pain reduction, inflammation reduction or the like. In one example, treating the features, such as the features 206 within the tooth 200 includes, at 1006 conveying light through a light passage such as the light passage 112 of the light based dental instalment 100 to the one or more light delivery ports 116 of the instrument 100. As shown in Figure 2, the light delivery ports 06 are provided by the instalment shaft 104 within the tooth 200, for instance, along the root canal 204. In another example, conveying ultraviolet light through the light passage 1 12 includes reflecting one or more wavelengths of light along a reflective inner wall 302, for instance, as shown in Figure 3B. At 1008, treating features 206 within the tooth includes delivering one or more wavelengths of light to the features 206 within the passage or cavity through the one or more light delivery ports 116. As previously described herein, and shown, for instance, in Figure 2, a plurality of light delivery ports 116 are optionally provided along the instrument shaft 104 to accordingly broadcast light into one or more locations within the tooth 200. For instance, as shown in Figure 2, the features 206 are at various locations within the root canal 204 as well as the remainder of the tooth 200. By providing a plurality of light delivery ports 1 16, light delivered along the instrument shaft 02 is accordingly broadcast into the tooth 200 from the varied positions of the ports 116 to intercept and engage with each of these features 206. Accordingly, microorganisms (such as bacteria or the like) located at these features 206 are readily treated with the one or more wavelengths of light. Additionally, because the light is broadcast in one or more directions, the instrument shaft 104 is optionally manipulated within the tooth 200 to translate or rotate the instrument shaft 104 and sweep the light delivery ports 116 across one or more features such as the features 206 to enhance treatment of the interior of the tooth 200 through the manipulation.

In another example, the method 1000 includes irrigating the tooth 200, for instance, with one or more antimicrobial agents or the like. Light generated with the light based dental instrument 100 and broadcast from the light delivery ports 116 interacts with the irrigant 208 (shown in Figure 2) to accordingly generate one or more free radicals of the irrigant within the tooth 200. The light (e.g., ultraviolet light) excites the molecules of the irrigant within the root canal 204 to generate free radicals from the chemical solution, and the generated free radicals trigger cell death in resident bacteria in the irrigated zone. The free radicals readily interact with microorganisms or the like retained within the features 206 (including lateral passages, along fins and irregularities in the passage, and within biofilms, proteins, carbohydrates or the like) to thereby enhance the effectiveness of the irrigant 208.

Several options for the method 1000 follow. In one example, the method 1000 includes mechanically debriding the passage or cavity with an endodontic file having a file profile corresponding to an instrument profile of the instrument shaft 104 (or 902). In another example, delivering light to the passage or cavity of the tooth 200 includes triggering cell death in resident microorganisms.

In another example, treating features with light includes treating features with ultraviolet light having a wavelength from 200 to 450 nanometers.

Optionally, treating features with ultraviolet light includes treating features with ultraviolet light having a wavelength from around 200 to 280 nanometers for killing microorganisms in the passage or cavity, and treating features with ultraviolet light having a wavelength from around 280 to 400 nanometers to promote one or more of tissue regeneration, revascularization, inflammation reduction or pain reduction. In another option, treating features with light includes treating features with ultraviolet light having a wavelength from around 280 to 315 nanometers to promote one or more of tissue regeneration or revascularization. In yet another option, treating features with light includes treating features with ultraviolet light having a wavelength from around 315 to 400 nanometers to promote one or more of inflammation reduction or pain reduction.

In other examples, the method 1000 includes focusing light through a lens 920 interposed between a light source 904 and the light passage 914.

Optionally, a lens-shaft spacing 922 matches a focal length of the lens 920. In another example, the lens-shaft spacing 922 is less than the focal length of the lens 920 (including the lens 920 in contact or close proximity to the shaft 902).

Several examples and experimental results are provided herein. These examples and results discuss various configurations of light based dental instruments, treatment schemes, therapeutic benefits, results and the like. At least some of these examples are prophetic, while others include lab results. The instruments, such as the light based dental instruments 100, 900 described herein, may have differing results from these examples and results. Bacterial decontamination of infected root-canal (RC) systems prevents or heals apical periodontitis. A study was conducted and completed to develop a stable polymicrobial biofilm with four commonly isolated bacteria in previously treated teeth with persistent infection (e.g., Enterococc s facaelis (EE),

Actinomyces viscos s (AM), Porphyromonas gingivalis (PG), and

Fusobacterium nuclealum (FN)). Initial studies in the development of a tooth model system involved biofilm on agar plates. The species of bacteria were grown as single cultures for 24-48 hours (incubated according to species requirements) and spiral-plated onto selective/differential agar plates.

Multispecies biofilms were also prepared on enriched blood agar plates.

Polymicrobial biofilms and single-species biofilms were subjected to our Ultraviolet (UV) light disinfection protocol. Agar plates were incubated according to species requirements for 48-72 hours and zones of inhibition were measured. UV light was placed at 83-89 millimeters over the agar surfaces with different exposure times ranging from 15-240 seconds. Treatment of single species and multi-species biofilms with the UV light exhibited strong bactericidal activity. Exposure to different times (15-240 seconds) was compared by one-way

(ANOVA, p<0.05). No statistical significant differences were found. These results suggest clinical significance for this disinfection protocol. In one example, a 15-second UV exposure regimen is incorporated into endodontic treatment as described herein. In conclusion, a stable reproducible polymicrobial biofilm model in human mandibular teeth was developed. This model is used with one or more of the light based dental instruments described herein.

This disclosure details a device and methods for disinfecting passages and cavities in teeth including root canals. Although described herein with regard to root canal procedures, the device and methods are similarly applicable to treatment in peri-implantitis procedures, periodontitis procedures and the removal and treatment of cavities. Optionally, the instruments described herein (e.g., instruments 100, 900) are used in a variety of therapeutic procedures including, but not limited to, dental procedures such as root canals, catheter based therapies including vascular and digestive procedures, surgical procedures, and introduction or guiding of other instruments (e.g., the components described, such as the light passages, ports, reflective inner walls and the like are provided around a delivery or guide lumen of an introducer or guide catheter).

Furthermore, the device and methods described herein (e.g., with the application of various wavelengths of light including ultraviolet light) are used in some examples as a unitary treatment. In still other examples, the device and methods described herein are used in concert with other treatments including chemical irrigation to increase the efficacy of the irrigation (e.g., through the generation of additional free radicals, additional disinfection with ultraviolet light, or the like). The approach used (in one example) in combination with a more standard irrigation procedure has great promise in achieving complete (e.g., total or near total) elimination of residual viable microorganisms in the root canal system.

The use of ultraviolet light (UV) at a wave length of about 254 nm is used for disinfection in one example. The disinfection benefits of ultraviolet light at or around this wavelength is less selective and thereby ensures a broader range of disinfection. The objective of this study is to assess the efficacy of UV light introduced into the canal space by the light based dental instruments described herein.

Initial studies focus on further development of the polymicrobial biofiims within our human tooth model. Our general approach is to expose biofiims within the canals via the light based dental instruments alone and in combination with NaOCl. Determination of elimination of biofiims is done by a number of approaches, including removal of canal contents and viable cell enumeration via anaerobic culturing, live/dead staining approaches, and determination of levels of DNA within the canal spaces following treatment.

Due to the canal system complexity, use of the traditional irrigation techniques is, in some examples, limited by the irrigant ability to fully reach the lateral canals, fins and delta. Use of UV light delivered by the approaches described herein has clinical relevance in achieving disinfection of these areas regardless of irrigant presence.

The proposed treatment includes both a mechanical and chemical treatment procedure and the application of one or more wavelengths of light (e.g., with one of the light based dental instruments discuss herein). The endodontic procedure includes the chemical -mechanical approach to root canal disinfection. The mechanical access and debridement of the root canal space is a step in the process of cleaning and disinfection, but because of the varying anatomy within teeth, it has its limitations. Further, bacteria in other examples are received and to some extent protected within biofilms, collections of proteins, carbohydrates and the like. Mechanical and chemical debridement are, in some examples, ineffective to access and kill bacteria within biofilms.

Chemical irrigation disinfects or dissolves and removes necrotic tissue from the canal space. It is believed, based upon the results provided herein, that the adjunctive use (or unitary use in another example) of an ultraviolet light source set at bactericidal wavelengths (around 200 to 280 nanometers, and including 2 5 nanometers) will increase the success rate of root canal treatment with one or more functions: the direct contact of the light with the bacteria dissociates the bacteria cell wall causing cell death, and UV light in contact with the chemical irrigant results in the breaking of the chemical bonds and enhanced generation of free radicals (e.g., chloride ions). The chemical irrigant free radicals can act as bactericidal bombs within the root canal system, and are extremely reactive with the bacteria causing the bacteria to die, Further, the combination of chemical and ultraviolet treatment can reveal and kill bacteria otherwise concealed and protected within features of the tooth including, but not limited to, biofilms (whether in the root canal or other locations within or around the oral cavity).

As described herein, the testing of four main bacteria commonly found in infected root canal spaces the application of the UV light source at around 245 nm from a range of 30-60 seconds resulted in approximately 99 percent of bacteria killed. Based upon these findings and the other examples described herein it is believed that these techniques and combinations of techniques (chemical, mechanical and ultraviolet or ultraviolet alone) will significantly reduce the bacterial load within the canal system leading to higher success rates and lower dental health finds.

Preliminary results show UV light applied to polymicrobial lawn containing four bacterial species typically isolated from failed root canal treatments on agar plates shows no bacterial growth in treated areas. These results showed no significant difference in the time or distance of exposure, which proves clinical relevance. Disinfection of the root canal system occurs using this method without adding significant length to the overall treatment time.

Examples of light based dental instalments are provided herein.

Additionally, light based medical instruments are also included with this disclosure. An example light treatment medical device includes an instrument shaft having a light delivery passage therein. In one example, the light delivery passage includes a reflective inner wall of the instrument shaft. The reflective inner wall is configured to deliver light from a light source (e.g., in a handle or base unit) through the instrument shaft and to one or more light delivery ports. Optionally, the medical device includes a fluid dispenser coupled with the base or handle. The fluid dispenser is configured to deliver a flow of fluid (e.g., liquid or gas, such as saline, air or the like) through the instrument shaft and to the one or more light delivery ports. Optionally, the fluid dispenser provides a flow of fluid through a separate lumen within the instrument shaft to one or more fluid delivery ports. The fluid dispenser and flow of fluid is used in an example to disrupt biofiims from one or more features including, but not limited to, surfaces of a catheter such as the inner surface of a catheter lumen, locations of interest within the anatomy or the like. The instrument optionally provides the light source and the fluid dispenser in combination to enhance the effectiveness of the instrument to sterilize a location or other instrument such as a catheter. For instance, the fluid dispenser is used to clear one or more the light delivery- ports and disrupt biofiims including bacteria therein on a medical device such as a catheter. The light source delivers light through the (cleared) light delivery- ports to the (disrupted) biofilm. The light is readily delivered into and through the biofilm because of the previous disruption caused with the application of the fluid. The fluid may additionally improve delivery of light to the area of interest by increasing scattering of light through the root canal, passage, cavity, or other anatomical space. Optionally, the application of fluid and light are repeated to further enhance the sterilization of the location or device.

Example 1

Microbial Culture and Growth Microbial cultures. Enter ococcus faecalis ATCC 29212 and Escherichia coli ATCC 12795 were obtained from the ATCC (ATCC, Manassas, VA).

Microbial broth and agar media and growth conditions. E. faecalis and E. coli were grown in TSBYE broth containing trypticase soy broth (30 gm/1, Becton, Dickinson and Company, Sparks, MD) and 0,5 percent yeast extract (5 gm/1, Fisher Scientific, Fairlawn, NJ).

E. faecalis and E. coli were also grown on TSBYE agar containing trypticase soy broth (30 gm/1, Becton, Dickinson and Company, Sparks, MD), 0.5 percent yeast extract (5 gm/1, Fisher Scientific, Fairlawn, NJ), and 1.5 percent agar (15 gm/1, Difco Agar granulated, Becton, Dickinson and Company, Sparks, MD), E. faecalis and E. coli were also grown on Tryptic Soy Agar containing 5 percent defibrinated sheep blood (Remei, Lenexa, KS).

Cultures were incubated for 24 hours in an incubator at 37 degrees C, Assay to assess surface killing. To assess the antimicrobial effects of light, a surface killing assay was established . E. faecalis and E. coli were cultivated in TSBYE broth. After 3 hours, the microbial culture turbidity was adjusted to an optical density of 80 percent transmittance (0.108 optical density) at 600 fiffl in a spectrophotometer (Spectronic 20D1, Thermo Fisher Scientific, Inc., Waltham, MA, USA). Culture suspensions adjusted to this concentration typically contained 5, 1 x 10 7 CFU/ml. Culture suspensions were swabbed onto a TSEYE agar plate and allowed to dry (~ 5 minutes).

Bacteria on the agar surface were exposed to different light sources for differing times through instrument shafts of differing compositions, lengths, and diameters. After treatment, TSEYE agar plates were incubated for 16-24 hours at 37 degrees C.

Light sources. As described herein in some instances the description of the light source includes the use of a lens. As shown in the figures herein (e.g., Figure 9) the light source 904 and the lens 920 are contained within the light source housing, such as the handle 102 shown in Figure 2, and are positioned between 7-8 mm from the terminal end of the hub 903, The hub 903 is used to hold the instrument shaft 902. The hub 903 is optionally configured to contain a luer locking system or system that allows positioning of the instalment shaft 902 within the desired distance from the light source 904 (if the device does not contain a lens) or from the lens 920. The instrument shaft 902 is a specified length (and may vary between instruments) to penetrate a passage or cavity within the oral cavity. One of ordinary skill in the art will appreciate that for shallow cavities a shorter instrument shaft is used.

Example 2

Light source configuration

Referring to Figure 9, the light source 904 and the lens 920 are contained in close proximity to each other (e.g., optionally adjacent, with a source-lens spacing 910 of 0 millimeters) and within a housing, such as the handle 102. The light source and the lens 920 are positioned between 7-8 millimeters from the terminal end of the hub 903.

Example 3

Antimicrobial Activity after Exposure to 405 nm Light

An LED light source 904 admitting 405 nm wavelength of light was used to evaluate its ability to kill E. faecalis using the TSBYE media described in Example 1, above, E. coli was not tested. The 405 light source sample contained a light source 904 and a lens 920 focusing the light emitted from the LED.

Example 4

Antimicrobial Activity 255 nm and aluminum instrument shaft

The assay described above was used to evaluate custom fabricated aluminum shafts having an internal diameter of 1.65 mm and a length of 33.0 mm. 4 different exposure times were tested for both E. coli and E. faecalis. After 120 seconds the 255 light source fitted with a prototype aluminum instrument having an internal diameter of 1.65 mm fabricated from aluminum foil killed E. faecalis and E. coli. There was no observable difference between the circle area of no microbial growth indicating antimicrobial activity on that agar when the instrument shaft proximal portion 908 was set to abut the lens 920 (with lens- shaft spacing 922 of 0 millimeters) or when the distance approximated the focal point of the lens 920 (having lens-shaft spacing 922 matching the lens 920 focal length, such as 10 millimeters). The diameter of the killing area was close to the internal diameter of the prototype aluminum instrument shaft (e.g., had a similar profile of shape and size). In another example, the lens 920 concentrates light from the light source 904 and accordingly increases the intensity of the light applied to the E. faecalis and E. coli and accordingly enhances cell death of the microorganisms or decreases treatment time (e.g., to a span less than 120 seconds).

Example 5

Tube Dimensions

Aluminum tubing was fabricated and tested using the methodology described in Example 1, above. Instrument shafts 33.0 millimeters in length and having bore sizes of 2.39 mm, 1.58 mm, and 0.89 mm were tested. After 30-120 seconds the 255 light source fitted with a prototype aluminum instrument shaft- fabricated from these 3 tubing stocks killed E. faecalis and E. coli as well as the light source without the instrument shaft. The diameter of the killing area was similar to the internal diameter of the prototype aluminum instrument shafts fabricated from tubing stock. Aluminum — — — Killing Killing 255 nm light source

(<30 sec) (<30 sec) only

Aluminum 2.39 33.0 nun 8 mm Killing Killing 255 nm light source mm (<30 sec) (<30 sec) +33 nun long, 1/8" stock

Aluminum 1.58 33.0 mm 8 mm Killing Killing 255 nm light source mm (<30 sec) (<30 sec) +33 mm long, 3/32" stock

Aluminum 0.89 33.0 mm 8 mm Killing Killing 255 nm light source mm (<30 sec) (<30 sec) +33 mm long, 1/16" stock

Aluminum 2.39 33.0 mm 0 mm Killing Killing 255 nm light source mm (<30 sec) (<30 sec) +33 mm long, 1/8" stock

Aluminum 1.58 33.0 mm 0 mm Killing Kiliing 255 nm light source mm (<30 sec) (<30 sec) +33 mm long, 3/32" stock

Aluminum 0.89 33.0 mm 0 mm Killing Killing 255 nm light source mm (<30 sec) <30 sec) +33 nun long, 1/16" stock

Example 6

Stainless Steel Comparison to Aluminum

Stainless steel tubes having a bore size of 0.40 mm and a barrel length of 50.0 mm were compared to aluminum tubes having a barrel length of 50 mm and a variety of bore sizes. The 255 nm light source was used for ail samples. See Table below. The results indicate that stainless steel tubes will work comparably to the aluminum. It is also noted that E. Jaecalis was not killed when it was cultured on blood agar prepared as described above. Through modification of the wavelength of one or more of the light source (e.g., modulation with a controller 700, second light source or the like) and the time of exposure E. jaecalis would be likely be killed in the context of the blood agar.

Stainless 0.40 50 mm 0 mm Killing Killing Killing in 20 steel mm (TSE-YE) (TSE-YE) seconds (Ef); killing in 30 seconds (Ec);

1/16", 0.40 ID

Aluminum 0.89 50 mm 0 mm Killing Killing Killing in 10

mm (TSE-YE) (TSE-YE) seconds (El); killing in 10 seconds (Ec);

1/16" stock

Aluminum. 1.58 50 mm 0 nun Killing Killing Killing in 10

mm TSE-YE) (TSE-YE) seconds (Ef); killing in 10 seconds (Ec);

3/32" stock

Stainless 0.40 50 mm 0 mm No Killing No killing in 30 steel mm Killing (BA) seconds (Ef); killing

(BA) in 10 seconds (Ec);

1/16", 0.40 ID

Aluminum 0.89 50 mm 0 mm No Killing No killing in 30 mm Killing (BA) seconds (Ef); killing

(BA) in 10 seconds (Ec);

1/16" stock

Aluminum 1.58 50 mm 0 mm No Killing No killing in 30

mm Killing (BA) seconds (Ef); killing

(BA) in 10 seconds (Ec);

3/32" stock

Example 7

Method of treating oral cavity with antibiotic wash and light exposure The 255 nm wavelength LED light source was used to evaluate synergistic killing of Έ. faecalis with an antibiotic wash. An example typical of that seen in endodontic laboratories is sodium hypochlorite (NaOCl). In this example, the 255 nm wavelength LED had synergistic killing activity with 3 percent NaCIO chemical irrigant. Treatment with the 255 nm wavelength LED for 60 seconds (without the NaCIO chemical irrigant) killed E. faecalis and cfu/ml were reduced when compared to control untreated E, faecalis. Treatment with the 255 nm wavelength LED for 60 seconds and then treatment with the chemical irrigant containing 3 percent NaOCl for 5 minutes killed all E. faecalis and cfu/ml were reduced when compared to both control, untreated E. faecalis and 255 nm wavelength LED treated E. faecalis that was not treated with the chemical irrigant. In comparison, treatment of E. faecalis with only 3 percent NaOCl for 5 minutes resulted in higher cfu/ml than seen for the untreated negative control, possibly due to dissociation of the 'colony forming units' into individual cells or cleavage of the diplococcal E. faecalis cells into 2 individual cells by short exposure to low concentrations of NaOCl, This suggests that the increased killing by the combination of 255 nm wavelength and 3 percent NaOCl is synergistic and may provide a significant clinical advantage over treatment with NaOCl alone. Example 8

Selection of light, source, lens and instrument shaft for design of devices One of ordinary skill in the art will appreciate that the devices described herein are designed to deliver a variety of light intensities to the cavity within the oral cavity. For example a bulb emitting more light can be chosen over one that delivers less light. The distance of the instrument shaft proximal end portion 106, 910 from the light source 110 (or 904), the inclusion of a lens 920 and the selection of the materials included in the instrument shaft 104 (or 902) impact the intensity of the light emitted from the one or more light delivery ports 1 16 (or 916). Upon successful achievement of the use of light commuted down an instrument shaft to kill bacteria (e.g., disinfect a feature of microorganisms), further modifications of the instruments 100 (or 900) are possible.

Using software to model light transmission down an i strument shaft having a known reflectivity facilitates the testing of a variety of parameters. For example, COMSOL Multiphysics ® is a general-purpose software platform, based on advanced numerical methods, for modeling and simulating physics-based problems. The COMSOL Ray Optics Module is used to model electromagnetic wave propagation in a light based dental instrument corresponding to a dental file. For instance, the instrument shafts described herein are optionally configured with an instrument profile matching (e.g., identical to or

approximating) file profiles of existing dental files. Because the example wavelengths described herein, 200 to 455 nanometers (and including 255 nanometers) are much smaller than the smallest geometric detail in the model the electromagnetic waves are modeled as rays that propagate through homogeneous or graded media. Because it is not necessary to resolve the wavelength with a finite element mesh, ray trajectories are computed over long distances (relative to the light wavelength) at a low computational cost. Rays undergo reflection and refraction at boundaries between different media.

The COMSOL Ray Optics Module was used to predict transmission of ultraviolet light in a light based instrument 900 with the following parameters: 100 rays released from an LED light source 904 with a conical shape with a cone angle of 23 degrees: the LED positioned 5 mm from a planoconvex lens 920 with focal length of 10 mm, center thickness 2.6 mm, refractive index of 1.5168, and reflectivity of 4 percent: the lens 920 is positioned 10 mm from a proximal end portion 910 of a cylindrical tube (e.g., the instrument shaft 902) having the lengths, bore sizes, and materials specified in the below table. Rays that do not enter the instrument shaft 902 are assumed to freeze upon hitting the boundary (e.g., the hub 903) 10 mm from the lens 920. Stainless steel is assumed to have a reflectivity in UV of 35 percent, and aluminum is assumed to have a reflectivity in UV of 90 percent.

Example 9

Delivery of light through an angled or curved tube

An angled or curved instalment shaft may be used to deliver light in one or more of the instruments 100, 900 described herein. Bends of less than 90 degrees were introduced to an aluminum instrument shaft 104 with bore size 1.58 millimeters and barrel length 50.0 millimeters. The instrument shaft 104 was used in conjunction with the 255 nm light source 1 10 as described herein. Killing was observed for E. faecalis on TSBTE agar after 120 seconds of exposure to the 255 nm light wavelength with bends including, but not limited to, zero (0) degrees (e.g., straight), 10 degrees, 40 degrees, and 50 degrees.

Example 10

A Method of Decreasing Microbial Growth in a Void in a Mammal

The instruments 100, 900 optionally include a light dispersing structure at the distal end portions 108, 912 of the instrument shafts 104, 902. The light dispersing structure includes, in one option, the same material as that of the instrument shaft. In one example, the light dispersing structure includes perforations in the walls of the instrument shaft 104, 902. In another example, the light dispersing structure also includes a closure at the distal end of the instrument shaft (e.g., a cap, weld dot, crimp or the like). Optionally, the closure includes perforations configured to disperse light and expose a larger tissue surface area to the light. Alternatively, the distal end portions 108, 912 of the instrument shafts 104, 902 include lenses that disperse light (e.g., diverging lenses). The scattering of the light by lens positioned distally relative to the proximal end portions 106, 910 allows for greater coverage of exposed tissues (e.g., a larger surface area receives the disperse light). Various Notes & Examples

Example 1 can include subject matter such as a light based dental treatment device comprising: a handle; an instrument shaft extending from the handle, an instrument profile of the instrument shaft is configured for delivery into a cavity or passage of a tooth, the instrument shaft includes: at least one light delivery port along the instalment shaft, and a reflective inner wall surrounding a light passage, the light passage extends through the instrument shaft to the at least one light delivery port; and a light source in communication with the at least one light delivery port though the light passage, the light source is configured to generate light in one or more wavelengths, and the reflective inner wall is configured to reflect light from the light source to the at least one light delivery port. Example 2 can include, or can optionally be combined with the subject matter of Example I, to optionally include, wherein the light source includes a unitary light source configured to generate light in two or more wavelengths.

Example 3 can include, or can optionally be combined with the subject matter of one or any combination of Examples 1 or 2 to optionally include a multiplexer module coupled with the light source, the multiplexer is configured to operate the light source to generate light in two or more wavelengths.

Example 4 can include, or can optionally be combined with the subject matter of one or any combination of Examples 1-3 to optionally include wherein the light is configured to generate light between around 200 to 280 nanometers and between around 315 to 400 nanometers.

Example 5 can include, or can optionally be combined with the subject matter of one or any combination of Examples 1-4 to optionally include wherein the light source is configured to generate light having a wavelength between 200 and 450 nanometers.

Example 6 can include, or can optionally be combined with the subject matter of Examples 1-5 to optionally include wherein the light source consists of one or more of an LED, laser diode, laser or quantum cascade laser.

Example 7 can include, or can optionally be combined with the subject matter of Examples 1-6 to optionally include wherein the light source includes a first wavelength LED configured to deliver light at a first wavelength and a second wavelength LED configured to delivery light at a second wavelength different from the first wavelength.

Example 8 can include, or can optionally be combined with the subject matter of Examples 1-7 to optionally include wherein at least one of the first and second wave lengths consist of at least one of a disinfection wavelength, regeneration wavelength, revascularization wavelength, inflammation reduction wavelength or pain reduction wavelength.

Example 9 can include, or can optionally be combined with the subject matter of Examples 1-8 to optionally include wherein the reflective inner wall extends a proximal end portion of the instrument shaft to the at least one light delivery port. Example 10 can include, or can optionally be combined with the subject matter of Examples 1-9 to optionally include wherein the instrument shaft includes at least one bend, and the reflective inner wall delivers light through the bend.

Example 1 can include, or can optionally be combined with the subject matter of Examples 1-10 to optionally include wherein the bend includes a curve shape in the instrument shaft.

Example 12 can include, or can optionally be combined with the subject matter of Examples 1 - 1 to optionally include wherein the bend includes an angle in the instrument shaft relative to a light axis of the light source.

Example 13 can include, or can optionally be combined with the subject matter of Examples 1- 2 to optionally include wherein the at least one light delivery port is at a distal end portion of the instrument shaft.

Example 14 can include, or can optionally be combined with the subject matter of Examples 1-13 to optionally include wherein the at least one light delivery port includes a plurality of light delivery ports.

Example 15 can include, or can optionally be combined with the subject matter of Examples 1 -14 to optionally include wherein the at least one light delivery port includes a plurality of light delivery ports spaced along the instrument shaft.

Example 16 can include, or can optionally be combined with the subject matter of Examples 1 - 5 to optionally include wherein the reflective inner wall has a reflectivity of at least 11 percent or greater.

Example 17 can include, or can optionally be combined with the subject matter of Examples 1- 6 to optionally include wherein the reflective inner wall has a reflectivity of at least 35 percent or greater.

Example 18 can include, or can optionally be combined with the subject matter of Examples 1-17 to optionally include wherein the reflective inner wall has a reflectivity of at least 90 percent or greater.

Example 19 can include, or can optionally be combined with the subject matter of Examples 1 - 8 to optionally include wherein the instrument shaft includes at least one of medical grade aluminum, medical grade stainless steel or a nickel titanium alloy. Example 20 can include, or can optionally be combined with the subject matter of Examples 1-19 to optionally include a lens interposed between the light source and the instrument shaft.

Example 21 can include, or can optionally be combined with the subject matter of Examples 1 -20 to optionally include wherein the lens includes a focal length proximate to the lens spacing from a proximal opening of the light passage.

Example 22 can include, or can optionally be combined with the subject matter of Examples 1 -21 to optionally include wherein the lens includes a refractive index of around 1.5, a focal length of 10 millimeters, and a center thickness of 2.6 millimeters.

Example 23 can include, or can optionally be combined with the subject matter of Examples 1-22 to optionally include wherein the light source is spaced from the light passage around 0 to 20 millimeters.

Example 24 can include, or can optionally be combined with the subject matter of Examples 1-23 to optionally include wherein the instrument shaft is at least 15 millimeters in length.

Example 25 can include, or can optionally be combined with the subject matter of Examples 1-24 to optionally include a method for treating a tooth comprising: positioning an instrument shaft within a passage or cavity in the tooth, the instrument shaft includes at least one light delivery port proximate a distal end portion of the instrument shaft within the passage or cavity; and treating features within the passage or cavity with ultraviolet light from the at least one light delivery port, treating features includes: conveying ultraviolet light through a light passage of the instalment to the at least one light delivery port within the passage or cavity, conveying ultraviolet light includes reflecting ultraviolet light along a reflective inner wall of the instalment shaft, and delivering the ultraviolet light to the features within the passage or cavity through the light delivery port,

Example 26 can include, or can optionally be combined with the subject matter of Examples 1 -25 to optionally include wherein delivering the ultraviolet light to the passage or cavity of the tooth includes triggering cell death in resident microorganisms. Example 27 can include, or can optionally be combined with the subject matter of Examples 1-26 to optionally include irrigating the passage or cavity with a chemical solution including an antimicrobial agent before treating the passage or cavity with ultraviolet light.

Example 28 can include, or can optionally be combined with the subject matter of Examples 1-27 to optionally include wherein delivering the ultraviolet light to the root canal includes: exciting the molecules of the chemical solution within the root canal to generate free radicals from the chemical solution, and triggering cell death in resident bacteria in the irrigated zone with the generated free radicals.

Example 29 can include, or can optionally be combined with the subject matter of Examples 1-28 to optionally include generating ultraviolet light within a handle coupled with the instrument shaft, the handle configured for positioning within the oral cavity.

Example 30 can include, or can optionally be combined with the subject matter of Examples 1-29 to optionally include generating ultraviolet light remotely from the instrument shaft and a handle coupled with the instrument shaft and transmitting the generated ultraviolet light through a fiber optic cable to the light delivery port.

Example 31 can include, or can optionally be combined with the subject matter of Examples 1-30 to optionally include mechanically debriding the passage or cavity with an endodontic file having a file profile corresponding to an instrument profile of the instrument shaft.

Example 32 can include, or can optionally be combined with the subject matter of Examples 1-31 to optionally include wherein a depth stop is movably coupled along the instrument shaft, and positioning of the instrument shaft within the passage or cavity includes: spacing the depth stop from the light delivery port according to a specified plunge depth of the light delivery port into the passage or cavity, and positioning the light delivery port within the passage or cavity at the specified plunge depth according to the depth stop.

Example 33 can include, or can optionally be combined with the subject matter of Examples 1 -32 to optionally include wherein treating features with ultraviolet light includes treating features with ultraviolet light having a wavelength from 200 to 450 nanometers.

Example 34 can include, or can optionally be combined with the subject matter of Examples 1-33 to optionally include wherein treating features with ultraviolet light includes: treating features with ultraviolet light having a wavelength from around 200 to 280 nanometers for killing microorganisms in the passage or cavity, and treating features with ultraviolet light having a wavelength from around 280 to 400 nanometers to promote one or more of tissue regeneration, revascularization, inflammation reduction or pain reduction, Example 35 can include, or can optionally be combined with the subject matter of Examples 1-34 to optionally include wherein treating features with ultraviolet light includes treating features with ultraviolet light having a wavelength from around 280 to 315 nanometers to promote one or more of tissue regeneration or revascularization.

Example 36 can include, or can optionally be combined with the subject matter of Examples 1-35 to optionally include wherein treating features with ultraviolet light includes treating features with ultraviolet light having a wavelength from around 315 to 400 nanometers to promote one or more of inflammation reduction or pain reduction.

Example 37 can include, or can optionally be combined with the subject matter of Examples 1-36 to optionally include focusing ultraviolet light through a lens interposed between a light source and the light passage.

Example 38 can include, or can optionally be combined with the subject matter of Examples 1-37 to optionally include a light based medical device comprising: a handle; an instalment shaft extends from the handle, an instrument profile of the instrument shaft configured for delivery into one or more of an anatomical lumen, passage or cavity, the instrument shaft includes: a light delivery port at a distal end portion of the instrument shaft, and a reflective inner wall surrounding a light passage, the light passage extends through the instrument shaft to the light delivery port; and a light source in communication with the light delivery port though the light passage, the light source is configured to generate light in one or more wavelengths, and the reflective inner wall is configured to reflect light from the light source to the at least one light delivery port.

Example 39 can include, or can optionally be combined with the subject matter of Examples 1-38 to optionally include wherein the light source includes a light source configured to deliver light at multiple wavelengths.

Example 40 can include, or can optionally be combined with the subject matter of Examples 1-39 to optionally include wherein the light source is configured to generate ultraviolet light between around 200 to 400 nanometers.

Example 41 can include, or can optionally be combined with the subject matter of Examples 1-40 to optionally include wherein the light source consists of at least one of an LED, laser diode, laser or quantum cascade laser.

Example 42 can include, or can optionally be combined with the subject matter of Examples 1-41 to optionally include wherein the reflective inner wall includes a reflectivity of 35 percent or greater.

Example 43 can include, or can optionally be combined with the subject matter of Examples 1-42 to optionally include a lens interposed between the light source and the light passage.

Example 44 can include, or can optionally be combined with the subject matter of Examples 1-43 to optionally include a method for light based treatment comprising: positioning an instrument shaft within one or more of an anatomical lumen, passage or cavity, the instrument shaft includes at least one light delivery port and a reflective inner wall surrounding a light passage extending through the instrument shaft to the at least one light delivery port; and treating a portion of the anatomy within at least one of the anatomical lumen, passage or cavity with light from the at least one light delivery port, treating including: conveying light through the light passage to the at least one light delivery port according to reflection along the reflective inner wall, and delivering the light to the portion of the anatomy through the at least one light delivery port.

Example 45 can include, or can optionally be combined with the subject matter of Examples 1-44 to optionally include wherein the at least one light source includes a first light source and a second light source, and generating light includes: generating a first wavelength light with the first light source, and generating a second wavelength light with the second light source. Example 46 can include, or can optionally be combined with the subject matter of Examples 1-45 to optionally include a method for decreasing microbial growth in a void within a mammalian body comprising: inserting a tube having a distal opening, a proximal opening, an exterior surface, an interior surface, and a shaft length of at least 15 mm into the void; and exposing the void within the mammalian body to light having a wavelength of from about 200 nanometers to about 450 nanometers for at least 15 seconds, wherein the light is commuted through the interior of the tube.

Example 47 can include, or can optionally be combined with the subject matter of Examples 1-46 to optionally includ e wherein the void is a cavity within the oral cavity.

Example 48 can include, or can optionally be combined with the subject matter of Examples 1-47 to optionally include wherein the void is an abscess.

Example 49 can include, or can optionally be combined with the subject matter of Examples 1-48 to optionally includ e wherein the abscess is an oropharyngeal abscess or a retropharyngeal abscess.

Example 50 can include, or can optionally be combined with the subject matter of Examples 1 -49 to optionally include wherein the interior surface has a reflectivity equal to or greater than 35 percent.

Example 51 can include, or can optionally be combined with the subject matter of Examples 1-50 to optionally include wherein the tube is made from aluminum or stainless steel.

Example 52 can include, or can optionally be combined with the subject matter of Examples 1-51 to optionally includ e wherein the void includes a void within an oral cavity formed during a procedure selected from a root canal, an implant or a bone graft.

Example 53 can include, or can optionally be combined with the subject matter of Examples 1-52 to optionally includ e wherein exposing the void comprises a first exposure at a wavelength of light from about 225 to about 275 nanometers, and a second exposure at a wavelength of light from about 400 to about 450 nanometers.

Example 54 can include, or can optionally be combined with the subject matter of Examples 1-53 to optionally include a method of decreasing microbial growth in a cavity within the oral cavity comprising: flushing a cavity in the oral cavity with an antimicrobial solution; and exposing the cavity in the oral cavity to light having a wavelength of from about 200 nanometers to about 450 nanometers.

Example 55 can include, or can optionally be combined with the subject matter of Examples 1-54 to optionally include wherein the light is delivered through a tube having a shaft length of at least 15 mm.

Example 56 can include, or can optionally be combined with the subject matter of Eixamples 1 -55 to optionally include allowing the antimicrobial solution to stay in contact with the cavity in the oral cavity for at least 30 seconds.

Example 57 can include, or can optionally be combined with the subject matter of Examples 1-56 to optionally include wherein exposing the cavity includes exposing the cavity to the light for at least 5 seconds.

Example 58 can include, or can optionally be combined with the subject matter of Examples 1-57 to optionally include a device for deli vering light having a wavelength from about 200 nanometers to about 50 nanometers to a cavity in the oral cavity comprising: a light source; a tube having a shaft length of at least 15 millimeteSrs and having a first distal opening and a proximal second opening, wherein the light source is from about 0 mm to about 20 mm from the proximal opening.

Example 59 can include, or can optionally be combined with the subject matter of Examples 1-58 to optionally include comprising a lens in between the light source and the proximal opening.

Example 60 can include, or can optionally be combined with the subject matter of Examples 1-59 to optionally include wherein the tube has an interior surface and the interior surface has a reflectivity such that there is at least 1 percent transmission of light at the distal opening relative to an initial quantity of light at the proximal opening,

Example 61 can include, or can optionally be combined with the subject matter of Eixamples 1 -60 to optionally include wherein the tube is made from aluminum or stainless steel. Various Notes & Examples

Each of these non-limiting examples can stand on its own, or can be combined in various permutations or combinations with one or more of the other examples.

The above detailed description includes references to drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention can be practiced.

These embodiments are also referred to herein as "examples." Such examples can include elements in addition to those shown or described. However, the present inventors also contemplate examples in which only those elements shown or described are provided. Moreover, the present inventors also contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein.

In the event of inconsistent usages between this document and any documents so incorporated by reference, the usage in this document controls.

In this document, the terms "a" or "an" are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of "at least one" or "one or more." In this document, the term "or" is used to refer to a nonexclusive or, such that "A or B" includes "A but not B," "B but not A," and "A and B," unless otherwise indicated. In this document, the terms "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein." Also, in the following claims, the terms "including" and "comprising" are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fail within the scope of that claim. Moreover, in the following claims, the terms "first," "second," and "third," etc, are used merely as labels, and are not intended to impose numerical requirements on their objects.

The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to comply with 37 C.F.R. § 1.72(b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than ail features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various

combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.