SUPPORT A DENTAL PROSTHESIS

Field of the Invention

[1] The present invention relates to a jaw implants and in particular, but not necessarily entirely, to a subperiosteal implant for an edentulous alveolar of the maxilla or mandible of the jaw.

Background

[2] Dental rehabilitation following loss of teeth is achieved by removable dental prostheses (eg. Dentures) or fixed bridgework supported by osseointegrated dental implants. In situations where there is insufficient supporting alveolar bone, removable dental appliances become unstable and unsuitable. The option of osseointegrated dental implants in cases of bone deficiency is possible through bone grafting to augment the alveolar ridge to accommodate the dental implant screw fixtures. Bone grafting can either be done simultaneously at the time of implant placement, but more often than not, bone grafting is done 4-10 months prior to implant insertion to allow consolidation of the grafted alveolar before it is loaded with an implant.

[3] In cases of severe alveolar atrophy of the jaws, especially in medically brittle older patients, the requirement for significant and complex bone grafting is contraindicated because of the potential high morbidity involved. Therefore, there is a pressing need for a simpler solution that is quick and easy and entails low morbidity. Furthermore, the solution needs to provide a stable and predictable base for the support of artificial teeth that can be placed soon after the implant is installed.

[4] Subperiosteal jaw implants were first conceived in the 1940's as large metal frames made of stainless steel or cobalt chrome that were passively placed directly onto the jaw bone without any fixation. Instability of such devices was very high, as was the failure rate. In the 1960's and 1970's, screw fixation was introduced but the devices yielded less than ideal outcomes because of the excessive size of the frame that required significant soft tissue stripping and the incompatibility of the materials used that reacted to the surrounding soft tissues, which finally led to the abandonment of the technique all together.

[5] The present invention seeks to provide a subperiosteal jaw implant, which will overcome or substantially ameliorate at least some of the deficiencies of the prior art, or to at least provide an alternative.

[6] It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country. Summary of the Disclosure

[7] There is provided herein a subperiosteal jaw implant that is a versatile, easy to install, dependable and accurate solution to dental prosthetic rehabilitation, particularly in jaws which lack sufficient alveolar bone to support conventional dental implants. The subperiosteal jaw implant of present embodiments not only avoids the need for complex adjunctive procedures such as onlay bone grafts, expensive barrier membranes, sinus lift surgery as well as intrusive zygomaticus implants, the subperiosteal jaw implant also simplifies the process of dental rehabilitation in less than ideal situations such as where there is not enough jaw bone to support dental implants.

[8] Specifically, according to one aspect, there is provided a subperiosteal implant for dental prosthesis for edentulous alveolar ridge fixation, the implant comprising a biocompatible baseplate being anatomically contoured and perforated for submucosal implantation and fixation to the alveolar bone; and at least one transmucosal abutment protruding from the baseplate for the fixation of dental prosthesis thereto.

[9] The biocompatible baseplate may be substantially uniformly perforated.

[10] The biocompatible baseplate may be substantially entirely perforated.

[11] The baseplate anatomically may curve in the axial plane.

[12] The baseplate may axially cover substantially the entire alveolar ridge.

[13] The baseplate may axially cover a portion of the alveolar ridge.

[14] The baseplate may be anatomically arched perpendicular the axial plane thereby defining labial and lingual aspect flanges.

[15] The baseplate may be anatomically contoured for fixation to the maxillar alveolar ridge

[16] A central portion of the labial aspect flange may comprise a central narrowing in the coronal plane to inferiorly avoid the nasal cavity.

[17] Opposite lateral portions of the labial aspect flange rise superiorly for maxilla fixation laterally adjacent the nasal cavity.

[18] The lingual aspect flanges comprise a central narrowing in the axial plane thereby defining lateral palate engaging flanges for engaging lateral aspect of the palate.

[19] The palate engaging flanges are substantially horizontally oprientated.

[20] The baseplate may be anatomically contoured for fixation to the mandibular alveolar ridge

[21] The at least one transmucosal abutment may be at last one pair of abutments being symmetric about the sagittal plane.

[22] The one pair of abutments may be at least two pairs of abutments.

[23] The one pair of abutments may be three pairs of abutments. [24] The least two pairs of abutments may comprise an anterior pair and a posterior pair, and wherein the implant may be configured such that, when the implant may be fixed in place, the anterior pair reach further inferiorly than the posterior pair.

[25] The subperiosteal implant may further comprise the dental prosthesis and wherein the dental prosthesis may comprise a tooth supporting base configured for fixation to the at least one transmucosal abutment.

[26] The tooth supporting base may comprise 8 artificial teeth.

[27] The perforated base plate may comprise apertures each having a diameter of about 1.7mm.

[28] The base plate may have a mediolateral width of about 49 mm.

[29] The base plate may have anteroposterior width of about 30.7 mm.

[30] The at least one transmucosal abutment may comprise a substantially cylindrical body.

[31] The substantially cylindrical body may comprise a diameter of about 4 mm.

[32] The abutment terminates in a hex nut head.

[33] The hex nut head may comprise a width of about 2.4 mm.

[34] The body may comprise interior screw threading.

[35] The interior screw threading may have a thread width of about .4 mm.

[36] The interior screw threading may have a depth of about 3.7 mm.

[37] The interior screw threading may have a major diameter of about 2 mm.

[38] The interior screw threading may have a minor diameter of about 1.57 mm.

[39] The biocompatible baseplate may comprise medical grade titanium.

[40] The medical grade titanium may comprise Ti-6AI-4V.

[41] The biocompatible baseplate may comprise a roughened osseointegration surface.

[42] According to a further aspect, there is provided a method of implanting the subperiosteal jaw implant as disclosed herein.

[43] The method may comprise forming an alveolar crest incision and insertion of the subperiosteal jaw implant via the alveolar crest incision.

[44] The method may further comprise microfixation to the alveolar bone.

[45] Microfixation may comprise choosing a plurality of suitably located apertures from those of the perforated baseplate and inserting microfixation screws through the plurality of apertures.

[46] The method may further comprise stitching the alveolar crest incision closed leaving the at least one transmucosal abutment protruding.

[47] The method may further comprise fixation of a dental prosthesis to at least one transmucosal abutment. [48] The fixation of the dental prosthesis to the at least one transmucosal abutment may comprise the fixation of a dental prosthesis within 24 hours of the implantation of the implant.

[49] Other aspects of the invention are also disclosed.

Brief Description of the Drawings

[50] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which:

[51] Figure 1 shows a perspective view of a subperiosteal jaw implant in accordance with a first embodiment;

[52] Figure 2 - 4 show exemplary dimensions of the subperiosteal jaw implant of the first embodiment;

[53] Figure 5 - 8 show exemplary representations of the subperiosteal jaw implant in accordance with a second embodiment specifically suited for fixation to the maxillar alveolar ridge;

[54] Figure 9 - 10 show the subperiosteal jaw implant fixated to the maxillar alveolar ridge;

[55] Figure 11 shows the subperiosteal jaw implant in accordance with a third embodiment specifically suited for fixation to the mandibular alveolar ridge;

[56] Figures 12 - 13 show the subperiosteal jaw implant in accordance with the third embodiment fixated to the mandibular alveolar ridge; and

[57] Figures 14 - 15 show exemplary dimensions of the transmucosal abutment. Description of Embodiments

[58] For the purposes of promoting an understanding of the principles in accordance with the disclosure, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Any alterations and further modifications of the inventive features illustrated herein, and any additional applications of the principles of the disclosure as illustrated herein, which would normally occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the disclosure.

[59] Before the structures, systems and associated methods relating to the subperiosteal jaw implant are disclosed and described, it is to be understood that this disclosure is not limited to the particular configurations, process steps, and materials disclosed herein as such may vary somewhat. It is also to be understood that the terminology employed herein is used for the purpose of describing particular embodiments only and is not intended to be limiting since the scope of the disclosure will be limited only by the claims and equivalents thereof. [60] In describing and claiming the subject matter of the disclosure, the following terminology will be used in accordance with the definitions set out below.

[61] It must be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[62] As used herein, the terms "comprising," "including," "containing," "characterised by," and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method steps.

[63] It should be noted in the following description that like or the same reference numerals in different embodiments denote the same or similar features.

Subperiosteal jaw implant 1

[64] In the accompanying illustrations, there is provided a subperiosteal jaw implant 1 for dental prosthesis for fixation to an edentulous alveolar ridge of the maxilla or mandible.

[65] Specifically, turning to figure 1, there is shown the implant 1 in accordance with one embodiment. As is shown in the figure, the implant 1 comprises a biocompatible baseplate 2 configured for submucosal implantation and exposure to the underlying bone of the edentulous alveolar ridge.

[66] As can be seen, the biocompatible baseplate 2 is compact so as to be distinguished from the large metal frames of prior art arrangements, thereby allowing for simpler installation in avoiding significant soft tissue stripping and other disadvantages of prior art large metal frame arrangements.

[67] Specifically, turning to figures 9 and 10, there is shown the fixation of the implant 1 at the maxillar alveolar ridge 3 whereas figures 12 and 13 show the fixation of the implant 1 at the mandibular alveolar ridge 4.

[68] As is further shown from figure 1, the base plate 2 is anatomically contoured to the alveolar ridge. Specifically, the baseplate 2 is curved in the axial plane being substantially U-shaped to follow the alveolar ridge 1 in the axial plane.

[69] In the embodiment shown in Figure 1, the implant 1 is configured to substantially fit the full arc or arch of the edentulous alveolar ridge. However, in embodiments the implant 1 may be configured for smaller segments of edentulous alveolar ridge to, for example, support a dental prosthesis comprising between 1 to 8 artificial teeth.

[70] The baseplate 2 is further anatomically arched perpendicular the axial plane thereby defining labial 11 and lingual 13 aspect flanges for fixation to respective labial and lingual surfaces of the alveolar ridge. [71] Furthermore, the baseplate 2 is perforated, comprising apertures 5. As will be described in further detail below with reference to the method of implantation of the implant 1, the apertures 5 are suited for the placement of micro fixation screws. With reference to the exemplary dimensions of the implant provided in figure 2, the diameter of the apertures 5 may be approximately 1.7 mm.

[72] As such, during the implantation of the implant 1, the surgeon may select an appropriate subset of the available apertures 5 for the insertion of micro fixation screws therethrough so as to adequately anchor and support the implant 1. In this regard, as can be further seen, the apertures 6 substantially uniformly located across the entirety of the baseplate 2 so as to place apertures 6 at substantially any position that may be utilised during the installation thereof.

[73] The unoccupied apertures 5 may further enhance bone growth and osseointegration and permit blood supply to the overlying covering mucosa and gingervae.

[74] As is further shown in figure 1, the implant 1 further comprises at least one transmucosal abutment 6 suited for the fixation of dental prosthesis thereto. In this manner, the baseplate 2 anchors the implant 1 to the alveolar bone of the such that the transmucosal abutments 6 are able to protrude through the covering mucosa so as to expose screw fixation points for the fixation of a dental prosthesis thereto comprising a plurality of teeth.

[75] The dental prosthesis may comprise a base comprising inferior fixation points spaced so as to match the location and spacing of the abutments 6 of the implant 1 so as to allow fixation thereto.

[76] The dental prosthesis may comprise a plurality of superior teeth which may be custom made to suit the patient. As alluded to above, the dental prosthesis may support differing numbers of teeth depending on the application such as, for example, between 1 to 8 teeth.

[77] Figures 14 and 15 show the transmucosal abutment 6 in further detail. In this particular configuration the transmucosal abutment 6 accommodates universal screw threads of most other dental implant systems so that dentists around the world can build false teeth dental implants that suit the present implant 1.

[78] Specifically, figure 14 shows a side elevation view of the abutment 6 wherein, as can be seen, the interior of the abutment 6 comprises screw threading 7 for the fixation of a corresponding threaded screw therein.

[79] The threading 7 may have a thread spacing of approximately .4 mm and may extend to a depth of approximately 3.7 mm. Furthermore, the threading 7 may have a major diameter of about 2 mm and a minor diameter of approximately 1.57 mm. A void 8 of approximately 1 mm may remain beyond the threading 7. Furthermore, considering figure 15 showing a top plan view of the abutment 6, as can be seen, the abutment 6 comprises a substantially cylindrical body 9 terminating in a hex nut head 10. In the embodiment shown, the cylindrical body 9 has a diameter of about 4.1 mm and the hex nut head 10 a width of about 2.4 mm.

[80] In the embodiment shown in figure 1, the implant 1 comprises 6 abutments being symmetric about the sagittal plane.

[81] Turning onto figure 2, there is shown a front elevation view of the implant in accordance with the first embodiment. As can be seen, in the embodiment provided, the implant 1 may comprise a mediolateral width of approximately 49.1 mm.

[82] As can be seen, the labial flange 11 may comprise a central narrowing 12 in the coronal plane so as to avoid the nasal cavity once implanted.

[83] Turning onto figure 3, there is shown a side view of the implant 1 wherein, as can be seen, the implant 1 comprises an anteroposterior width of approximately 30.7 mm. As can be further seen from figure 3, the anterior abutments 6 may extend further inferiorly as compared to those posterior abutments 6. Furthermore, as can be seen, the abutments 6 may be orientated substantially parallel.

[84] Turning onto figure 4, there is shown a bottom view of the implant 1. In the embodiment shown, the labial flange 13 may comprise a narrowing in the axial plane. Furthermore, the labial and lingual flanges 11, 13 may splay openly posteriorly.

[85] Turning to figures 5 - 8, there is shown a particular embodiment of the implant 1 specifically suited for fixation to the maxilla. As can be seen from figure 5, the labial flanges 11 stand proud so as to take advantage of the available maxilla bone surface area adjacent the nasal cavity. Specifically, figure 6 showing the posterior view of the implant 1 shows the labial flanges raising laterally so as to define the central narrowing 12 therebetween for nasal cavity avoidance. Figure 9 shows the implant 1 in place wherein, as can be seen, the labial flange 11 is fixated to the maxilla adjacent and beneath the nasal cavity 14.

[86] Furthermore, in this embodiment, the lingual flanges 13 are more horizontally poised as compared to the more vertically poised labial flanges 12 so as to suit fixation to the substantially horizontal palate behind the alveolar ridge. As can be seen from the rear view of figure 6, the lingual flanges 13 may similarly be substantially bifurcated having a narrowing 14 therebetween in the axial plane so as to define lateral palate flanges 15 for fixation to lateral aspects of the palate. Is also shown in figure 6, the horizontal lateral palate flanges 15 may comprise at least three apertures 5 for bone fixation.

[87] In accordance with this embodiment, the implant 1 is as shown in figure 5 may comprise a height of about 20.5 mm. Furthermore, as shown in figure 6, the implant 1 may comprise a width of about 40.5 mm in the coronal plane. [88] Furthermore, as is shown from the bottom view of the implant 1 shown in figure 7, the implant 1 may comprise a total anteroposterior width of about 18 and a central anteroposterior width of approximately 7 mm.

[89] Furthermore, in accordance with the second embodiment, the abutments 6 comprises substantially "beehive" shaped body as opposed to the cylindrical body described above with reference to figure 15. Specifically, as is best shown in figure 6, the abutments 6 may comprise a base diameter of about 5 mm which steps down to approximately 2.5 mm.

[90] Turning to figure 11, there is shown a third embodiment of the implant 1 specifically suited for fixation to the mandible alveolar ridge 4. As is shown in this embodiment, the baseplate 2 is narrower than that of the first and second embodiments supporting 6 abutments.

[91] Figure 12 shows a front view of the implant 1 of this third embodiment fixated to the mandible alveolar ridge 4 and figure 13 shows a side view of the implant 1 of this third embodiment fixated to the mandibular alveolar ridge 4.

Method of im pla ntation of the su bperiostea l jaw impla nt

[92] The method of implantation of the jaw implant 1 may comprises the formation of an alveolar crest incision to expose the underlying alveolar bone and the insertion of the subperiosteal jaw implant 1 via the incision to contact the alveolar bone.

[93] Once placed on the bone, the surgeon will insert microfixation screws at suitably chosen locations to hold the implant 1 in place.

[94] Thereafter, the alveolar crest incision is stitched closed around the exposed transmucosal abutments 6.

[95] At an appropriate time thereafter, a dental prosthesis is fixed to the transmucosal abutments. As alluded to above, the dental prosthesis may be fixed to the implant 1 quite soon, such as within 24 hours.

[96] In embodiments, the subperiosteal jaw implant 1 is custom-made for each patient utilising CAD-CAM modelling and 3-D printing capabilities.

Adva ntageous effects

[97] As such, embodiments of the subperiosteal jaw implant 1 provides advantages over conventional dental implants used to support dental prostheses.

[98] For example, embodiments of the subperiosteal jaw implant 1 allow the ability to support artificial teeth in severely atrophic jaws without the need for complex adjunctive procedures such as onlay bone grafts, expensive barrier membranes, sinus lift surgery as well as intrusive zygomaticus implants [99] Furthermore, embodiments of the subperiosteal jaw implant 1 allow the ability to immediately load the implant with artificial teeth without a protracted period of healing since the micro-screws provide primary stability

[100] Furthermore, embodiments of the subperiosteal jaw implant 1 allows predictable positioning and parallel alignment of the transmucosal abutments which simplifies the design and construction of the dental prosthesis.

[101] Furthermore, embodiments of the subperiosteal jaw implant 1 allow for relatively easy and quick to installation with minimal additional surgical training required by the experienced practitioner.

[102] Furthermore, the compact baseplate 2 of the implant 1 avoids extensive soft tissue stripping as compared to conventional subperiosteal frames.

[103] It should be noted that any advantages or features described herein should not be construed as being necessarily applicable to all embodiments of the implant 1. It is further specifically stated that any advantage specifically described or alluded to herein should not be construed as necessarily being provided by each and every claim.

Interpretation

Embodiments:

[105] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.

[106] Similarly it should be appreciated that in the above description of example embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the Detailed Description of Specific Embodiments are hereby expressly incorporated into this Detailed Description of Specific Embodiments, with each claim standing on its own as a separate embodiment of this invention.

[107] Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

Different Instances of Objects

[108] As used herein, unless otherwise specified the use of the ordinal adjectives "first", "second", "third", etc., to describe a common object, merely indicate that different instances of like objects are being referred to, and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.

Specific Details

[109] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description. Terminology

[110] In describing the preferred embodiment of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as "forward", "rearward", "radially", "peripherally", "upwardly", "downwardly", and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms.

Comprising and Including

[111] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

[112] Any one of the terms: including or which includes or that includes as used herein is also an open term that also means including at least the elements/features that follow the term, but not excluding others. Thus, including is synonymous with and means comprising.

Scope of Invention

[113] Thus, while there has been described what are believed to be the preferred embodiments of the invention, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the scope of the invention. For example, any formulas given above are merely representative of procedures that may be used. Functionality may be added or deleted from the block diagrams and operations may be interchanged among functional blocks. Steps may be added or deleted to methods described within the scope of the present invention.

[114] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.