Technical Field

In the field of dental hygiene, it is known that it is advantageous to use a soft-bristle toothbrush for regular tr. home-cleaning regimens. This is particularly true, from the specialized view of the field of periodontistry. That area of dentistry is principally concerned with the physiology and pathology of the gums and other "soft-tissue" of the tooth-bearing region of the mouth, vis-a-vis the teeth themselves and their associated skeletal regions. More particularly, periodontistry is directed toward preventing and correcting the diverse effects of plague-causing bacteria in the gingival sulcus area under the gum flap which covers the base of the teeth.

In the daily home-practice of oral hygiene, periodontists strongly favor the use of toothbrushes having soft bristles. The reasons for this are to provide a brush which is sufficiently flexible to massage thoroughly the soft tissues of the mouth, to stimulate blood circulation, and to disorganize bacteria; all without causing undue trauma to the oral tissues. Further, the straight bristles normally used in a conventional brush, are not effective to scour comfortably under the gum flap.

Background Art

Currently, the bristles in toothbrushes are almost always made from thermo-plastic materials. Inherently, these are easily deformed. Soft bristles, being inherently even more supple and susceptible to bending than "hard"

bristles which are thicker and/or made from material which is more rigid structurally, are not useful for any reasonable period of time in the manner which periodontists particularly seek. Such bristles individually spread and bend over and become fixed more or less permanently in a multitude of directions, rather than staying aligned, more or less. Thus, the bristles do not present a coordinated mass of soft bristles to the brushed area. This can render the brush unusable, particularly over any considerable length of time, and even hazardous to the soft tissues in the mouth.

The long, soft bristles in the presently available designs are, inherently, individually, structurally weak, and readily collapse under pressure. For this reason, brushes are made available in the "medium" and "hard" bristle types so they will stand up better under the pressure of brushing. Yet these are counter-productive because the stiffer bristles have a greater tendency to injure the soft tissues. This tendency to injury increases as the bristles spread with use.

From the foregoing, it may be seen that:

All present brushes become permanently deformed with use and increasingly become unsatisfactory for use.

The basic shape of the present bristle design does not lend itself to reaching the vital sulcus area under the gum flaps.

The soft bristles rapidly become deformed with repeated use and do not present a resilient coordinated mass of soft

bristles for brushing action.

The "medium" and "hard" brushes provide increased resilience, when new, but soon take a self-defeating spreading set.

All of the above establishes a need for a brush made of soft bristles which are formed in a manner to substantially increase the effective resilience of the soft bristles, which eliminates the need for the "medium" and "hard" brushes; and which at the same time, produces a maintainable, coordinated mass of soft bristles, so formed that the sulcus area is properly addressed, and all surfaces are comfortably and effectively scoured.

A variety of proposals have been made for straightening brush bristles after use. Some of them contemplate pressing to a limited degree on the free ends of the outer bristles so as to cause them to deflect inwards, so as to make the group of bristles form a uniform mass without edge fraying. In this connection, reference is made to U.S. Patent No. 271,814; No. 637,522; No. 1,444,677; No. 3,120,019; and No. 3,995,743. However, even these prior art teachings do not produce results desired by periodontists and other such specialists in oral hygiene since, even when practiced with soft bristle brushes, the effect at best is merely to reduce edge-fraying. Conseguently, the prior art devices provide no greater remedial effect than is available in any soft toothbrush, even when brand new and unfrayed.

Accordingly, it is an object of this invention to provide a dental appliance having soft bristles formed into close juxtaposition in a unique, crucial region proximal their free ends with the free ends of said bristles flared outward with respect to the region in which they are closely juxtaposed.

Still another object of this invention is to provide a dental appliance in which the resiliency of the tooth- contacting portion of the bristles is enhanced by shape and juxtaposition.

Another object is to provide a dental appliance whose bristles are bent at a crucial point, and the ends are formed into a coordinated mass of soft bristles.

Another object of this invention is to provide a dental appliance whose end bristles are reformed after each use into a unique coordinated mass of soft bristles.

Another object of this invention is to provide such a dental appliance in which the portion of the free ends of said bristles above the crucial pressure area will flare outward with respect to the region in which they are closely juxtaposed.

Another object of the invention is to provide such a dental appliance in which the lower portion of bristles below the crucial bending and pressure area are formed into a wedge-like shape which converges at the pressure point.

Another object of this invention is to identify the location of the crucial pressure area in relation to the length of the bristles, above which point the flare and

supporting wedge are not formed, and below which crucial area the application of the knife edge bending pressure causes the bent bristles to splay outward instead of bending inward on themselves.

Another object of this invention is to provide a dental appliance whose flared bristle ends are re-established after each use.

Another object of the invention is to establish the bristles of the dental appliance into a shape that effectively eliminates the need for a "medium" or "hard" brush.

Yet another object of the invention is to provide a dental appliance including apparatus for forming the bristles of an associated toothbrush so that they fulfill at least one of the foregoing objects.

Still another object of this invention is to provide such apparatus in a form which is removably affixable after each use.

Another object is to apply all of the above to any soft bristle brush in which an upper, flared, coordinated mass of brush ends are supported by a trained, wedge-like formation of the coordinated lower mass of bristles so that brushing pressure causes the lower portion of the bristles to bend inward towards each other to gain increased resilient support, rather than to splay outward in individual weakness as in present cases.

Disclosure of Invention

The desired objects may be achieved through practice of this invention, embodiments of which comprise a toothbrush having bristles which are closely juxtaposed to each other in the crucial area in the region next to their free ends, enabling the said ends to be splayed outward while the supporting bristles are trained inward, and methods and complementary apparatus for so forming such bristles wherein the bristles in said region are temporarily clamped at a crucial point into such closely juxtaposed position after each use.

Brief Description of the Drawings

This invention may be understood from the description which follows and from the accompanying drawings which form a portion of this disclosure and wherein:

FIG. 1 is a perspective view of an unmodified toothbrush which may be used in the practice of the present invention;

FIG. 2 is a perspective view of a complementarily designed bristle former apparatus useful in carrying out the present invention;

FIG. 3 is a cross-sectional view of the apparatus shown in FIG. 2 with a brush of the type shown in FIG. 1, being used in carrying out the present invention;

FIG. 4 is a cross-sectional view of the apparatus and brush shown in FIG. 3 in a further step of carrying out the present invention;

FIG. 5 is a cross-sectional view of a toothbrush of the type shown in FIG. 1 after having been formed by apparatus of the type shown in FIG. 2 in accordance with the teachings of the present invention;

FIG. 6 is a cross-sectional view of the brush shown in FIG. 5 after its bristles have naturally opened into the desired relationship in response to the brushing action;

FIG. 7 is a cross-sectional view of another embodiment of this invention;

FIG. 8 is a cross-sectional view of another embodiment of this invention;

FIGS. 9a-i represent the progression of bristle training using my invention; and

FIGS. 10a and b show use of the brush to reach the sulcus region.

Best Mode for Carrying Out the Invention Referring first to FIG. 1, there is depicted a toothbrush 10 having a handle portion 12, one bristle holding end 11, and bristles 14, all of known per se construction. Typically, the handle and bristle holding portion of the toothbrush, as well as the bristles themselves, are made of thermoplastics, because the characteristic of softness in the bristles imparts to them the highly desirable ability to massage the gum tissues, improve blood circulation in the oral tissues, and dislodge bacteria so as to prevent plaque without causing undue trauma to the softer tissues in the mouth. However, the characteristic of softness causes the bristles to bend very

easily in many directions upon use. The bristles 14 are not sufficiently resilient to recover from such bending. Thus, after relatively few uses, the brush is no longer capable of performing its desired functions. My invention advantageously utilizes the tendency of the bristles to splay outwardly by compressing them at a crucial point with a clamp 16 so that they are in close juxtaposition in the region 15 proximal their free ends, preferably about 1/4 of the distance from the bristle ends 17. This causes the lower portion of the bristles, next to the holding end 11, to be formed into a wedge-shaped mass which provides support and resiliency to the bristle ends 17. When the clamp 16 is removed and the brush utilizes, the bristles being unrestrained, exhibit "memory" flexion towards being straight, causing the previously clamped region to open slightly. However, the bristle ends 17 stay bent at substantially the same angle with respect to the main body of the bristles, thus the bristle ends flare outwardly, enhancing their effectiveness in removing material from tooth surfaces under the gum flaps. The specific configuration may be seen in FIGS. 4, 5 and 6, hereinafter discussed. Complementary apparatus useful to achieve that purpose is shown in FIGS. 2 and 7-8 inclusive. The clamp apparatus 16 shown in FIG. 2 comprises handles 22, closure jaws 24 to impinge in the crucial area upon the outside of the bristles in a toothbrush, and a spring member 26 to impart bias to the jaws 24 toward closure against opening

moments of force imparted to them when the handles 22 are squeezed together. As such, it may be made from a variety of suitable known per se materials, such as plastic or metal, or in combinations of materials, such as plastic elements and metal spring members.

In a preferred embodiment, the entire structure is formed from plastic such as poly-chromate as a single molding having closure jaws 24, at the opposite end of a continuum from handles 22, and separated by a flexible cross bar 26, as shown in FIG. 2. By this means, the jaws 24 are biased against opening in response to squeezing together of the handles 22 by their structural integration with the cross bar 26 and the resulting flexure of the cross bar 26.

It has been found satisfactory if such a clamp is made having the following dimensions:

Center (brush holding) aperture = 9/16" Handle thickness = 1/8"

Jaw thickness = 1/4"

Cross bar (spring) thickness = .060" Handle length = 1-3/4"

Angle of divergence of handles = 10° However, it is to be noted that the dimensions of the bristle former must exactly complement the specific brush for which it is designed so that the brush is held in place, and knife-edge pressure is applied in the discovered crucial area at approximately the three-quarter/one-quarter point.

FIG. 3 illustrates a toothbrush being received into the brush holding channel of a clamp 16 of the type described

above; the clamp handles 22 having been pinched manually to cause them to deflect toward each other and against the clamp closure bias of the spring 26, with resulting opening of the clamp jaws 24. FIG. 4 illustrates the clamp 16 having been released on a brush so positioned, so that the jaws 24 compress the top ends of the bristles in the region

15. This process usually follows use of the brush, when the bristles are still somewhat warm and wet, and at least several hours typically pass before the brush is next put into use, so that in the interim the bristles take on a semi-permanent "set", with the region 15 of the bristles squeezed together in tight juxtaposition and with the main body of the bristles which lies between the compressed region 15 and the bristle end 11 of the brush 10 formed into a wedge which, in cross-section, is substantially an upright triangle. Essentially, the region of compression 15 occurs at about 1/4 of the distance down the bristle ends, as this provides a desirable depth for the flared cleaning surface as hereinafter described. It should be noted too that the configuration of the clamp also ensures proper positioning and retention of the brush, so that correct positioning of the clamping action is assured and is maintained.

As shown in FIG. 5, the dried bristles of the brush 10, upon removal from the clamp 16, will more or less retain the shape imparted to them while in the clamp. In as much as clamp removal usually occurs immediately before use of the brush, FIG. 5 depict the usual bristle configuration as the

brush bristles are presented to the teeth and gums for cleaning.

However, if some time elapses between removal of the clamp and use of the brush, the bristles will tend to become more nearly at right angles to the bristle-holding end of the brush 10 due to memory or the mechanical disarranging of the formed bristle wedge 18 by use itself. Although there may also be some straightening of the bristles in the region

15 where they have been clamped, such straightening is usually not pronounced. Consequently the configuration of the bristles when presented to the teeth and gums while the brush is in use is substantially as shown in FIG. 6. The bristle ends 17 are flared outward, so that in cross-section the group of them forms what maybe described as an inverted, truncated triangle, while the wedge-shaped mass 17 may be described as being (in cross-section) a wider based, upright, truncated triangle. The result is that the bristle ends 176 present a very resilient, soft yet orderly, flared array that is ideally suited for cleaning tooth surfaces and for penetration into the sulcus region between the inner surface of the soft gum flaps and the corresponding surfaces of the teeth below the gum line; and the lower supporting wedge of soft bristles bend inward upon themselves providing resilient support to the brushing surface. It follows with proper use of the brush and clamp 16 the desired characteristics of a toothbrush may be retained over long periods, with the same brush being "reconstituted" into the desired configuration described above after each use by

s imply re-cl amp ing it in cl amp 16 . Thus , with this invention , it is possible and practical to use soft or extra-soft bristles that otherwise would not provide the resilience or maintain the shape that is essential for continued use . This also eliminates the discomfort that results from the use of a hard bristle brush.

Although the clamp 16 depicted in FIGS . 2-4 and 7 is shown as being substantially circular in cross-section, it may be in any of a wide variety of regular or irregular configurations , or may be a feature of a mounted retainer or portable carrying case.

Since , as noted above , the clamp acts not only as a clamp , but as a positioner to assure that the proper location of the clamping action is assured and maintained, the embodiment of this invention shown in FIG . 7 will be seen to include an adapter 30 which may optionally be added to a clamp 16 of the type heretofore described for the purpose of adapting such a clamp 16 to accommodate smaller sized toothbrushes , such as those used by children. By this means , proper pos itioning o f the bristl es o f such a toothbrush vis-a-vis the location of the j aws 24 of the clamp 16 in order to carry out this invention may be assured.

FIG . 8 il lustrates another clamp 3 6 which i s an embodiment of this invention, in the form of an enclosing cover , made from metal , plastic , or other appropriate material . As such it includes a main body 37 with the upper

side walls thereof formed into j aw-like compression surfaces 38 , one of which ends with a retaining tab 39 , which engages the top of the other side wall such that a brush may be retentively retained with its bristles in the compressive mode hereinabove described.

It is to be noted that the foregoing embodiments of apparatus are il lustrative o f the various types o f structures that might be utilized for these purposes , and that a wide variety of other structures which provide opposing lines of clamping pressure to the free-end region of the brush bristles in the crucial area might be utilized within the contemplation of this invention. As a result of the use of such apparatus on soft-bristle toothbrushes after they have been used for dental hygiene purposes , the end regions of the constituent bristles become set in close juxtaposition as the bristles dry out. It should be further noted that the closure j aw portions , when closed on the bristles of a toothbrush in the region of their free ends which is short of the actual ends themselves , the grouping of bristles may be so re-formed that the area of closest juxtapositioning of the bristles to each other is in the crucial area somewhat below, rather than at, the actual ends of the bri stles . The ef f ect of this is to cause the br i stl e s as a group to become re - f o rmed into the configuration shown in FIGS . 2-9 inclusive . As such , a cross-section through the group of bristles taken at right angles to the long axis of the brush handle will be seen to be narrowest ( i . e . , with the constituent bristles most

closely juxtaposed) at about 1/4 of the bristle length below the top of the row of bristles, along the lines of contact of the closure jaws with the outside of long sides of the group of bristles. The effect of this, when the clamp is removed and the brush is put into use, is to cause the free ends of the group of bristles to splay outward, so that in cross-section, the group of bristles might be described as resembling somewhat the cross-section of a thistle flower. As such, the brush is rendered especially suited to render extraordinarily effective oral hygiene and cleaning ability. Although of soft texture, which facilitates gum massage and improved circulation, with minimized trauma to the soft tissues of the mouth, the configuration of the brush so modified is particularly adapted, due to the splaying of the group of bristle ends with close juxtapositioning of the bristle in the region immediately adjacent to the bristle ends, to invading the interstice between the gum flap areas and the adjacent tooth walls as shown in FIGS. 10a and 10b. The brush thereby is so re-formed as to provide superior hygiene and therapeutic effects. After use, which tends to splay the entire length of bristles and not merely their free end and will eventually render the brush substantially unfit for any useful purpose as far as mouth care is concerned, the brush may be re-clamped as previously described, to further enhance and re-establish the reformation of the previously described. Without the complementary clamp this could not be accomplished.

It is to be understood that the preceding description is by way of illustration and not of limitation, and that other embodiments may be made without departing from the spirit or scope of the invention.

While I have shown my invention in various forms, it will be obvious to those skilled in the art that it is not so limited but is susceptible of various changes and modifications without departing from the spirit thereof.