POCKET ORTHODONTIC BONDING PAD
A pocket orthodontic bonding pad for attaching orthodontic attachments to teeth wherein the orthodontic attachment is mechanically secured within a bonding pad pocket with a design that allows a slight buffering flexibility under masticatory stress and ease of removal of the orthodontic attachment. Upon removal of locking tabs the orthodontic attachment may be removed with minimal force, and the remaining bonding pad polished from the teeth with ease, which is most advantageous for brackets that tend to break upon removal and create high stress forces upon tooth structure. The ease of removing orthodontic attachments allows maximum bonding strengths.
This application claims the benefit of U.S. Provisional Application No. 62/011,423, filed Jun. 12, 2014. The disclosure of this prior application is incorporated herein by reference in its entirety for all purposes.
This invention relates in general to a polymer/plastic pocket orthodontic bonding pad for orthodontic attachments, mainly brackets. The pocket orthodontic bonding pad removably receives the orthodontic attachment which is locked into the pocket. Upon removal of the lock, the orthodontic attachment is removed with minimal pressure. This is particularly advantageous for orthodontic brackets, which tend to break upon removal. The pocket orthodontic bonding pad imparts a slight degree of flexibility to the orthodontic attachment, which buffers against masticatory forces. The pocket orthodontic bonding pad further allows maximum-strength bonding materials bonding to the tooth, wherein the bonding pad is designed to be the breakaway force determinant for the orthodontic attachment, this force being less than the force being necessary to break tooth enamel from a tooth. This is particularly advantageous because direct bracket/enamel bonds universally create microfractures in enamel when removed or debonded from teeth.
BACKGROUND OF THE INVENTIONWith the development of the ability to bond material to teeth, more particularly to tooth enamel, orthodontics was presented with bondable brackets and attachments. The strength of the bracket bond to a tooth was determined by the combination of the strength of the bond to the tooth, the strength of the bonding material, and the strength of the bond to the orthodontic attachment. The bond to the orthodontic bracket was facilitated by using bonding materials, such as acrylics, which readily formed a strong union with the bracket. Metal brackets and other attachments were developed with a mesh-type bonding surface that produced a semi-mechanical lock with the bonding material. Plastic brackets were easily broken and absorbed stains. Ceramic brackets were then developed.
Ceramic brackets, as described in U.S. Pat. No. 4,948,366, were made from mono-crystalline or poly-crystalline aluminum oxide, which were resistant to staining. The bonding surface of the ceramic bracket was treated with a silane coupling agent in order to enhance the strength of the bond with the bonding material. The ceramic material was similar to a diamond, hard and brittle, resulting in a surface hardness greater than that of tooth enamel If the ceramic bracket had an occlusal interference it would abrade the enamel of the opposing teeth. The orthodontic company rushed to market with this new product by advertising directly to the public, which created a public demand for the product before adequate clinical trials had been performed. Clinically, the orthodontist found that when attempting to remove the ceramic bracket from a patient's tooth, the tooth enamel would occasionally detach with the ceramic bracket. The strength of the ceramic bracket to enamel bond was greater than the enamel to the underlying tooth. Research revealed that the smooth bonding surface of the ceramic bracket treated with a silane-coupler greatly enhanced the attachment of the bonding material to the ceramic bracket. It was also found that this type of flat surface on the ceramic bracket produced a very thin layer of bonding film, which in turn produced a stronger bond. The thinner the bonding film the stronger the bond.
Ceramic brackets are often removed with the jaws of an orthodontic pin cutter by placing the cutting edges between the bracket base and the tooth and squeezing. The orthodontic ceramic bracket would often fracture upon attempted removal from the tooth, leaving a piece of the ceramic bracket still bonded to the tooth. At this point a dental drill would often have to be used to remove the piece of ceramic bracket from the tooth. The dental drill was not a perfect solution due to the nature of the hardness of the porcelain bracket. The dental drill most commonly used was diamond-coated, which had close to the same hardness as the porcelain bracket, and which was harder than tooth enamel The ceramic bracket was also the same color as tooth enamel Thus, tooth enamel could be inadvertently removed.
The mesh-backed metal brackets were more successful than the ceramic bracket. The mesh-backed metal bracket produced a greater thickness of bonding material, allowing enough space between the bracket and the tooth to allow the pin cutter to more easily wedge between the bracket and tooth and remove the bracket when the pin cutter jaws were squeezed together. The metal brackets would not fracture as the porcelain brackets did. The early metal brackets also had the ability to flex, wherein twin brackets could be gripped and squeezed by a pair of pliers, which broke the bond. Modernly, metal brackets are formed by metal injection molding and do not possess this flexing ability yet still will remain in one piece during removal.
Several attempts have been made to solve the debonding problem associated with ceramic brackets. For example, it was proposed in U.S. Pat. No. 4,455,138 that applying heat to the dental bracket would assist in loosening the adhesive bonding of the bracket to the tooth so that the ceramic bracket may be more easily removed with less force. It was found that this system was not always practical as the orthodontist may prematurely pull the bracket in anticipation of the loosening of adhesive, causing great pain to the patient and also shattering the bracket before the heat applied would loosen the adhesive. Further, the pulling force could not be directionally controlled with this system. In addition, the high temperatures associated with this method of removal could cause pulpal or nerve damage to the tooth.
Another debracketing tool and method of removal is disclosed in U.S. Pat. No. 4,907,965, where the heat and debracketing force is simultaneously applied. This system does not always assure that the adhesive is sufficiently loose to allow easy removal, and likewise requires engagement of the ceramic bracket during removal. In addition, the high temperatures associated with this method of removal could cause pulpal or nerve damage to the tooth.
A relatively flexible bonding pad is described in U.S. Pat. No. 5,098,288, wherein a bonding pad is secured to the bracket and bonded to the surface of a tooth. The attached pad is gripped by pliers, causing a buckling of the pad, breaking the bond between the pad and the tooth. The purpose was to prevent fracturing of the bracket during the removal process. However, the flexibility of the bonding pad does not allow for higher bonding strengths between the bonding pad and the enamel surface. In fact, increasing bonding strengths between the bonding pad and the enamel surface decreases flexibility of the bonding pad.
U.S. Pat. No. 5,263,859 describes a flexible bonding pad with holes, allowing the bonding material to come in direct contact with the bracket. The purpose was to increase the strength of the bond to the bracket. However, the flexibility of the bonding pad does not allow for efficient bonding strengths between the bonding pad and the enamel surface. In fact, increasing bonding strengths between the bonding pad and the enamel surface decreases flexibility of the bonding pad.
U.S. Pat. No. 6,786,720 discloses a light-curable methacrylate-based epoxy resin bonding pad molded to a ceramic orthodontic appliance. Debonding is performed by squeezing the pad with ligature cutters, causing the bracket to release from the tooth. However, the flexibility of the bonding pad does not allow for efficient bonding strengths between the bonding pad and the enamel surface. In fact, increasing bonding strengths between the bonding pad and the enamel surface decreases flexibility of the bonding pad.
Another factor involving orthodontic brackets is the unintentional debonding during the patient's treatment which is time-consuming for the orthodontist, and often delays the completion of the patient's treatment. Most commonly, the patient has eaten something too hard. Orthodontics is moving toward digitally-assisted bracket placement. If one failure occurs in treatment, it is virtually impossible to replace the bracket in the same position. With the trend in extended appointment intervals (from traditional 4-week intervals to current 8-10-week intervals), a broken bracket can greatly add additional treatment time and significant cost to the orthodontist due to the process involved to repair the unintentionally broken bond. The dilemma is that orthodontic bond strengths must be strong enough to adhere brackets to teeth yet weak enough that upon removal they do not fracture enamel, causing damage to the teeth. Further, the pulling force could not be directionally controlled with this system.
U.S. Pat. No. 7,819,660 discloses appliances that are not designed to resist or distribute masticatory shear forces of an occlusal gingival direction. The appliances rely on an expensive multitude of bracket bodies with different x-axis, y-axis, and z-axis positions.
Another debracketing tool and method of removal is disclosed in U.S. Pat. No. 4,907,965, wherein heat and debracketing force is simultaneously applied. This system does not always assure that the adhesive is sufficiently loose to allow easy removal, and likewise requires engagement of the ceramic bracket during removal. In addition, the high temperatures associated with this method of removal could cause pulpal or nerve damage to the tooth.
It is also known to provide a relatively flexible bonding pad or base for an orthodontic bracket to facilitate debonding, as disclosed in U.S. Pat. No. 5,098,288. However, it has been found that the bonding between the pad and the bracket often fails during treatment due to the various forces on the bracket during treatment, thereby necessitating re-bonding. Further, the flexibility of the bonding pad does not allow for efficient bonding strengths between the bonding pad and the enamel surface. In fact, increasing bonding strengths between the bonding pad and the enamel surface decreases flexibility of the bonding pad. In such instances, treatment has been interrupted, delaying the ultimate conclusion of treatment, and costly chair time is required to re-bond the bracket to the tooth.
SUMMARY OF THE INVENTIONOrthodontics is moving toward digitally-assisted bracket placement. If one failure occurs in treatment, it is virtually impossible to replace the bracket in the same position. With the trend in extended appointment intervals (from traditional 4-week intervals to current 8-10-week intervals) a broken bracket can greatly add additional treatment time. The dilemma is that orthodontic bond strengths must be strong enough to adhere brackets to teeth yet weak enough that upon removal they do not fracture enamel or damage teeth.
Tavas and Watts reported that shear/peel strengths of bonded adhesives should develop 3.9 to 5.9 MPa. While this relatively weak bond strength ensures easy removal of brackets, it also leaves the patient very susceptible to broken brackets through normal masticatory forces or not adhering to a brace-friendly diet. Literature reports bond strengths to 15 MPa with orthodontic adhesives. Enamel bond strengths of up to 38.3 MPa are currently possible with modern dental materials and it would follow that higher bond strengths will continue to evolve as time goes on. By increasing bond strengths, orthodontic appliances need not rely on surface area for bond strength, permitting orthodontic appliances to be much smaller. Smaller orthodontic appliances are particularly advantageous to dental aesthetics, comfort, and access for hygiene.
Brackets tend to debond through masticatory shear forces in an occlusal gingival direction. Therefore, a bracket that is resistant to this force vector and shock-absorbing to this force vector would be desired. Slight flexibility of the bonding pad tends to mitigate the effects of these shear forces. Current debonding techniques require the orthodontist to remove adhesive remnants from the teeth using a fine fluted finishing bur. Most adhesive remains on the teeth, so it is normal protocol and procedure that this removal process is common. The bonding pads of the present invention and adhesive can be limitless in mechanical and chemical adhesion to teeth, while negating debonding forces to remove bonding pads from teeth. Further, the bonding pads of the present invention are thin and easily destructible, further providing for easy removal.
The concept of the bonding pad is to (1) enable very high bond strength at the pad-enamel interface (chemical/etch retention) through a polymeric/plastic bonding pad that is mechanically attached to the attachment body; (2) enable the orthodontist to remove attachments at very low forces due to the unique design of the bonding pad/attachment interface, such that with a simple adjustment to the bonding pad, mechanical retention of the orthodontic attachment body to the bonding pad is reduced from high strength to near zero; and (3) design the bonding pad/attachment to allow shock absorption to distribute masticatory force. The occlusal-gingival, mesial-distal, and lingual-labial positions are made within the bonding pad's shape, but permit the use of a singular, standard attachment body, which tends to be the expensive and intricate component, especially with the advent of self-ligating orthodontic brackets that have multiple moving parts. The bonding pads are particularly suited to be individually fabricated, preferably specifically to the anatomy of each tooth of a patient, preferably specifically to the occlusal-gingival, mesial-distal, and lingual-labial positions on each tooth of a patient, and preferably printed by a three-dimensional printer.
The present invention enables the orthodontist to lower the forces at the debond appointment by a simple manipulation of the amount of mechanical retention of the orthodontic attachment to the bonding pad. A metal, ceramic, or polymer orthodontic attachment with a smooth base surface can be preferably shaped such that the gingival side is optionally narrow and tapers to a wider occlusal side. Alternatively, the metal, ceramic, or polymer orthodontic attachment with a smooth base surface can be preferably shaped such that the occlusal side is optionally narrow and tapers to a wider gingival side. In alternative embodiments, either of the left and right sides may be optionally narrow and tapered relative to the other. This preferable tapering ensures an easy path of draw in an occlusal direction. Optimal, preferable occlusal or gingival tapering also ensures resistance from an occlusal-gingival direction. The orthodontic attachment is enveloped mechanically in the bonding pad. The bonding pad can optionally be made out of a plastic or polymer that is similar to the bonding adhesives. Further, the bracket cannot be removed from the bonding pad unless the pad is destroyed by removal of locking features, thus creating an irreversible assembly for a more solid structure. This is particularly advantageous because reusable orthodontic bracket assemblies must balance the strength of bonding that permits bracket assembly removal and subsequent reattachment to a patient's tooth with the strength of bonding that prevents accidental dislodgement. The bonding pad of the present invention does not rely on flexibility to debond the attachment; instead, a rotary instrument is used to polish. Further, addition of an orthodontic attachment to the bonding pad adds rigidity to the bonding pad by acting as an underlying framework to support the bonding pad. The polymer mesh could optionally be impregnated with an anti-cariogenic or naturally occurring molecule with the ability to release calcium and phosphate ions, stabilize, and/or mitigate the common occurrence of enamel decalcification that is common around orthodontic bonding pads, such as fluoride, selenium, calcium, casein phosphopeptide (“CPP”), or amorphous calcium phosphate (“ACP”).
During debonding of the present invention, no shear forces or compressive forces need be applied to the interface between the bonding pad and tooth enamel Instead, the mechanical tab securing the orthodontic attachment or in the retentive aspects of the bonding pad is removed or polished away. Subsequently, a pliers or debonding tool engages the orthodontic attachment and lifts the attachment out of the pocket of the bonding pad in a gingival to occlusal direction. This debonding procedure eliminates the need to apply a prying or pulling force directly to the interface between the enamel and the bonding pad or orthodontic attachment, mitigating the enamel microfracture damage that occurs to tooth enamel during the typical debonding process.
The present invention relates to an orthodontic attachment bonding pad that contains retentive aspects that receive an orthodontic attachment and has a bonding surface that bonds to a tooth. The design of the pocket is to allow the removal of the attachment with minimal pressure. The pocket orthodontic bonding pad is comprised of a polymer/plastic material that is comprised of a highly bondable material that is of a hardness such that it can be easily removed from a tooth with a dental drill. The material and the design of the pocket orthodontic bonding pad are intended to produce a shock absorbing effect. The x-, y-, and z-directional axes are subsequently referred to and claimed by reference to mesial-distal, occlusal-gingival, and lingual-labial axes for relation to human anatomical dimensions, without respect to corresponding axes; no representation is made, for example, that the x-axis need be limited to specifically correspond to one of mesial-distal, occlusal-gingival, or lingual-labial over either of the others two. Additionally, “torque” refers to the rotation of a tooth on its long axis, especially the movement of the apical portions of the teeth by use of orthodontic appliances. “Angulation” refers to the deviation of a tooth from a straight line, i.e. an occlusal-gingival axis. “Tipping” refers to forcibly pivoting a tooth so that its crown is moved labially or lingually.
While the invention has been illustrated by a description of various embodiments and while these embodiments have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the inventive concept.
Claims
1.-25. (canceled)
26. A pocket orthodontic bonding pad comprising:
- a four-sided pad with a top occlusal side, a bottom gingival side, left and right sides, a front and a back and retentive aspects, wherein the retentive aspects are attached on three of the top occlusal side, the left side, the bottom gingival side, and the right side of the four-sided pad, such that one of the top occlusal side, the left side, the bottom gingival side, and the right side is a side to which no retentive aspect is attached, and the retentive aspects can receive a base of an orthodontic attachment
- a protruding surface located on one of the top occlusal side, the left side, the bottom gingival side, or the right side of the four-sided pad, the location of the protruding surface being on the side on which there is no retentive aspect, the protruding surface protruding toward the front of the four-sided pad, wherein the protruding surface encloses the side to which no retentive aspect is attached and to which the protruding surface is attached such as to prevent removal of a base of an orthodontic attachment from the retentive aspects during orthodontic treatment, the removal of the protruding surface permitting the base of the orthodontic attachment to be removed from the pocket orthodontic bonding pad with minimal pressure, and the more that the protruding surface encloses the base of the orthodontic attachment the greater the force that must be applied to remove the orthodontic attachment and
- a bonding surface on the back of the four-sided pad wherein the bonding surface is irregular in order to enhance the bonding strength to the enamel surface of a tooth;
- wherein the removal of the base of the orthodontic attachment is dependent upon prior removal of the protruding surface or upon prior removal of a retentive aspect
- wherein the pocket orthodontic bonding pad comprises a shape comprising occlusal-gingival, mesial-distal, and lingual-labial dimensions that are customizable via three-dimensional printing to (1) fit the enamel surface of a tooth such that the bonding surface cooperatively engages dental anatomical contours of enamel of an individual patient's individual tooth, and (2) vary thickness and angulation of the pad such that the orientation of the orthodontic attachment is positioned at a customized specific pre-determined occlusal-gingival, mesial-distal, lingual-labial position and torque when the orthodontic attachment base is received by the retentive aspects of the pocket orthodontic bonding pad.
27. A pocket orthodontic bonding pad as in claim 26, wherein the retentive aspects are attached on the left, bottom gingival, and right sides of the four-sided pad, and the four-sided pad is open to the top occlusal side, and the protruding surface is located on the top occlusal side of the four-sided pad, the protruding surface protruding toward the front of the four-sided pad, and wherein the protruding surface encloses the top occlusal side such as to prevent removal of the base of the orthodontic attachment from the retentive aspects during orthodontic treatment.
28. An orthodontic attachment received by the pocket orthodontic bonding pad of claim 26, comprising: the base that cooperatively engages the retentive aspects of the four-sided pad of the pocket orthodontic bonding pad, wherein the base has a back and a front and left and right sides and top and bottom sides and the base may be removed from the retentive aspects of the pocket orthodontic bonding pad on the top occlusal side of the pocket orthodontic bonding pad with minimal pressure, removal of the base from the retentive aspects of the pocket orthodontic bonding pad dependent upon prior removal of the protruding surface or a retentive aspect a stem attached to the front of the base; and a head attached to the end of the stem opposite the end of the stem attached to the front of the base, the head optionally receiving an archwire or other orthodontic device.
29. An orthodontic attachment as in claim 28 wherein the base left and right sides taper wider to the occlusal, facilitating removal of the orthodontic attachment to the occlusal.
30. An orthodontic attachment as in claim 28 wherein the base left and right sides taper wider to the gingival, facilitating removal of the orthodontic attachment to the occlusal.
31. An orthodontic attachment as in claim 28 wherein the orthodontic attachment is an orthodontic bracket or tube.
32. An orthodontic attachment as in claim 28, wherein the back of the base has a smooth surface, facilitating easy removal of the orthodontic attachment from retentive aspects of the pocket orthodontic bonding pad.
33. An orthodontic attachment as in claim 28 further comprising a relief channel in the orthodontic attachment base and stem from the top occlusal side to the bottom side, the orthodontic attachment to which mesial-distal pressure can be applied to collapse the orthodontic attachment base and remove the orthodontic attachment from the retentive aspects of the pocket orthodontic bonding pad.
34. An orthodontic attachment as in claim 28 further comprising a relief channel in the orthodontic attachment base and stem from the left side to the right side, the orthodontic attachment to which occlusal-gingival pressure can be applied to collapse the orthodontic attachment base and remove the orthodontic attachment from the retentive aspects of the pocket orthodontic bonding pad.
35. An orthodontic attachment as in claim 28 wherein the base provides rigidity to the bonding surface of the pocket orthodontic bonding pad when the base is locked within the pocket orthodontic bonding pad, and wherein the rigidity of the bonding surface is decreased upon removal of the base.
36. A pocket orthodontic bonding pad as in claim 26, wherein the retentive aspects attached on the left and right sides of the four-sided pad taper wider to the occlusal, facilitating removal of the orthodontic attachment to the occlusal following the removal of the protruding surface using a device such as a dental drill, the removal of the orthodontic attachment with the use of an orthodontic instrument such as band removing pliers.
37. A pocket orthodontic bonding pad as in claim 26, wherein the retentive aspects attached on the left and right sides of the four-sided pad taper wider to the gingival, facilitating removal of the orthodontic attachment to the occlusal following the removal of the protruding surface using a device such as a dental drill, the removal of the orthodontic attachment with the use of an orthodontic instrument such as band removing pliers.
38. A pocket orthodontic bonding pad as in claim 26 wherein the retentive aspects are a hollow pocket that is enclosed on the left, bottom gingival, and right sides, and open to the top occlusal side, and that can receive the orthodontic attachment.
39. A pocket orthodontic bonding pad as in claim 26 wherein the retentive aspects are tabs attached on the bottom gingival, and optionally the left and right sides of the four-sided pad, and that can receive the orthodontic attachment.
40. A pocket orthodontic bonding pad as in claim 26 wherein the pocket orthodontic bonding pad is a plastic/polymer or similar material suitably forming a strong bond with orthodontic bonding materials and such that the bonding surface can be easily removed from a tooth with a device such as a dental drill.
41. A pocket orthodontic bonding pad as in claim 26 wherein the front has a smooth surface.
42. A pocket orthodontic bonding pad as in claim 26 wherein the protruding surface is a tab.
43. A pocket orthodontic bonding pad as in claim 26 wherein the bonding strength between the bonding surface of the pocket orthodontic bonding pad and a tooth is at least 12 MPa.
44. A pocket orthodontic bonding pad as in claim 26, further comprising a spine in the middle of the front side of the four-sided pad from the top occlusal side to the bottom side, the spine protruding outward from the four-sided pad of the pocket orthodontic bonding pad, the spine filling a relief channel in an orthodontic attachment with a relief channel, the orthodontic attachment received in the retentive aspects of the pocket orthodontic bonding pad, and the spine diverting the orthodontic attachment with the relief channel outward or away from the pocket orthodontic bonding pad upon application of mesial-distal pressure to the orthodontic attachment with the relief channel.
45. A pocket orthodontic bonding pad as in claim 26 further comprising a spine in the middle of the front side of the four-sided pad from the left side to the right side, the spine protruding outward from the four-sided pad of the pocket orthodontic bonding pad, the spine filling a relief channel in an orthodontic attachment with a relief channel, the orthodontic attachment received in the hollow pocket of the pocket orthodontic bonding pad, and the spine diverting the orthodontic attachment with the relief channel outward or away from the pocket orthodontic bonding pad upon application of occlusal-gingival pressure to the orthodontic attachment with the relief channel.
46. A pocket orthodontic bonding pad as in claim 26 wherein the protruding surface is made of a thickness, shape, and surface area such that pressure released upon the removal of the closed pocket top is less than the bond strength of the adhesive between the four-sided pad and a tooth.
47. A pocket orthodontic bonding pad as in claim 26 wherein the protruding surface is made of a thickness, shape, and surface area such as to control or direct the occlusal-gingival, mesial-distal, and lingual-labial force vectors and affect removal of an orthodontic attachment in a pre-determined direction without prior removal of the protruding surface or prior removal of a retentive aspect.
Type: Application
Filed: Jul 29, 2019
Publication Date: Nov 21, 2019
Inventor: Robert T. Rudman (Denver, CO)
Application Number: 16/524,285