US20190247147A1 - Orthodontic devices and methods for using those devices - Google Patents

Abstract

A device for use by a clinician includes a tip structure that is configured to extend from a handle and to be inserted into a patient's mouth and at least one light source that is capable of emitting incoherent actinic radiation from the device. The light source is on the tip structure or within the handle. A light device includes a shell that is configured to engage an orthodontic bracket while the orthodontic bracket is attached to a tooth and at least one light source is embedded in the shell and is capable of emitting incoherent actinic radiation. A method of debonding an orthodontic appliance from a tooth includes exposing an adhesive secured to the tooth to incoherent actinic radiation that reduces a bond strength of at least a portion of the adhesive and separating the orthodontic appliance from the tooth at the portion of the adhesive having reduced bond strength.

Description

CROSS REFERENCE
• This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/628,577 filed on Feb. 9, 2018, the disclosure of which is expressly incorporated by reference herein in its entirety.
FIELD
• The present invention is generally related to the field of orthodontic devices and methods of using those devices.
BACKGROUND
• Current orthodontic treatment with orthodontic brackets or other devices that may be attached to the patient's teeth may require the enamel to be prepared prior to attachment of the device to the tooth. Preparation of the tooth surface may be through a series of steps including cleaning, acid etching, and sealing, with intermediate rinse and dry steps, before the clinician may apply an adhesive. For example, to bond a bracket to tooth enamel, each tooth is first cleaned with a slurry of abrasive, such as pumice, to remove pellicle from the enamel. Then, after rinsing and drying the cleaned surface, a phosphoric acid etchant is carefully placed on the surface locations of the tooth to which the clinician desires to attach the orthodontic device. The acid etching step demineralizes the enamel surface and removes a layer of approximately 30 μm or so of hydroxyapatite from the enamel rods. After between 30 and 90 seconds of etch time, the etchant is rinsed away with a water spray and a high flow evacuator. In this way, etching provides a porous structure.
• Following the drying step after etching, a sealant (e.g., Ortho Solo™ sealant) is applied to the etched surface. The sealant may penetrate the porous, acid etched surface. Once the sealant cures, a mechanical interlock is created between the tooth and the sealant. An adhesive (e.g., Enlight) and the bracket may be pressed onto the sealed surface with the adhesive between the bracket and the sealant. The adhesive may be a composite resin paste adhesive that includes a mixture of methacrylate monomers, a photo-initiator, and a glass/hydroxyapatite powder. Once the adhesive cures, it secures the bracket to the sealant. This bonding arrangement results in a sandwich-like construction with the sealant and the adhesive sandwiched between the tooth surface and the orthodontic bracket. This procedure and bonding arrangement is then repeated for each tooth that will receive an orthodontic device and so, in the case of orthodontic brackets and molar tubes, this may involve 28 teeth per patient.
• The current preparation process has many drawbacks. From the perspective of the clinician, it is a manually time-intensive process. It is not surprising that office chair time during the entire bonding procedure is lengthy. Overall, bonding orthodontic brackets to teeth is costly. From the patient's perspective, the process is uncomfortable and enamel removal is often irreversible due to the difficulty of remineralizing dental hard tissues. Thus, the tooth surface may be permanently compromised by acid etching. Certain patients may have an allergic reaction to the etchant. Liquid etchant may flow to the gingiva where it may irritate the soft tissue. Gel etchant, despite allowing more precise placement, requires skillful application and is more difficult to remove. In either application, when the etchant must be rinsed away, care must be taken not to splash or wash the etchant in a manner that may harm the patient or clinician, but the rinsing must be thorough so that the etching reaction is terminated and there is no residual acid or mineral debris that hinders the mechanical interlock between the tooth and the device.
• After orthodontic treatment is complete, the clinician must remove the orthodontic bracket from each tooth. This debonding process requires the clinician to break the bond formed during the bonding process. Mechanically fracturing the bond may require significant skill on the part of the clinician if the patient is to avoid pain. To debond orthodontic brackets, an orthodontist or a clinician may use a tool, such as a pair of pliers, to grip the bracket while it is bonded to the patient's tooth. With twisting motion, shear forces are applied to the bracket and the tooth. Once the applied shear force exceeds the adhesive bond strength, the bracket separates from the tooth. Even if done properly, debonding with a pair of pliers or a similar tool is disconcerting and uncomfortable for the patient. And, even with orthodontic brackets that include design features for easier debonding, considerable adhesive/sealant residue may be left on the tooth surface after removal of the bracket. This residue must be mechanically removed with a dental bur, which is also an extremely uncomfortable process for the patient and is tedious for the clinician.
• Therefore, a need exists for orthodontic devices, adhesives, and methods of using those devices and adhesives to reduce issues associated with debonding orthodontic devices from teeth.
SUMMARY
• The present invention overcomes the foregoing and other shortcomings and drawbacks of orthodontic devices, adhesives, and methods of using those devices and adhesives heretofore known for use in orthodontic treatment. While the invention will be described in connection with certain embodiments, it will be understood that the invention is not limited to these embodiments. On the contrary, the invention includes all alternatives, modifications and equivalents as may be included within the spirit and scope of the present invention.
• In accordance with the principles of the present invention, a device for use by a clinician in orthodontics comprises a tip structure that is configured to extend from a handle and to be inserted into a patient's mouth and at least one light source that is capable of emitting incoherent actinic radiation from the device. The light source is on the tip structure or within the handle.
• In one embodiment, the device further includes a sonic or ultrasonic generator coupled to the tip structure and configured to vibrate the tip structure.
• In one embodiment the device further includes the handle and a housing defines the handle and the sonic or ultrasonic generator is in the housing.
• In one embodiment, the at least one light source emits light in at least one of an IR spectrum, an NIR spectrum, and an UV spectrum to irradiate a cured adhesive within the patient's mouth.
• In one embodiment, the at least one light source includes a first light source for the IR or NIR spectrums and a second light source for the UV spectrum.
• In one embodiment, the first light source and the second light source are capable of being simultaneously activated so that the device emits light in each of the IR or NIR spectrums and the UV spectrum.
• In one embodiment, the device further includes a source of blue light that is capable of emitting light in a blue portion of a visible light spectrum to cure an adhesive within the patient's mouth.
• In one embodiment, the at least one light source is capable of producing an irradiance of 50 mW per cm²to 250 mW per cm².
• In one embodiment, the at least one light source is capable of producing an irradiance up to an amount that does not heat a cured adhesive within a patient's mouth.
• In one embodiment, the handle includes a socket and the tip structure is one of a set of a plurality of different tip structures, and each of the tip structures in the set is capable of being removably coupled to the handle in the socket.
• In one embodiment, the tip structure is L-shaped and includes a first leg and a second leg extending generally perpendicularly from the first leg.
• In one embodiment, the tip structure includes a shield that is configured to be positioned between adjacent teeth and to block light emitted from the device from impinging upon at least one tooth.
• In one embodiment, the tip structure includes a bite plate and a sidewall that is configured to face a surface of the patient's teeth and the at least one light source is positioned in the sidewall, the tip structure being configured to irradiate an entire arch of the patient's mouth.
• In one embodiment, the tip structure is configured to capture an orthodontic appliance when it separates from a tooth and prevents the orthodontic appliance from contacting a portion of the patient's mouth.
• In one embodiment, the tip structure is configured to apply a debonding force to the orthodontic appliance.
• In one embodiment, the tip structure includes a shell configured to physically contact the orthodontic appliance. In one embodiment, the shell includes a cavity defined in part by opposing projections. In one embodiment, the shell includes at least one projection capable of contacting and applying a tensile force on the orthodontic appliance.
• In one embodiment, the tip structure includes a tool for contacting the orthodontic appliance and the at least one light source is adjacent the tool.
• In one embodiment, the device further includes a fluid reservoir coupled to the housing.
• In one embodiment, the housing includes a port fluidly coupled to the fluid reservoir, the device being configured to eject fluid from the fluid reservoir from the port.
• In one embodiment, the port is adjacent the tool.
• In accordance with the principles of the present invention, a light device comprises a shell that is configured to engage an orthodontic bracket while the orthodontic bracket is attached to a tooth, and at least one light source is embedded in the shell and is capable of emitting incoherent actinic radiation.
• In one embodiment, the shell defines a cavity configured to receive the orthodontic bracket and the at least one light source is configured to irradiate the cavity.
• In one embodiment, the cavity includes opposing projections that are configured to create an interference fit with the orthodontic bracket when the bracket is in the cavity.
• In one embodiment, the shell further includes a U-shaped portion that is configured to fit over an occlusal edge of the tooth.
• In one embodiment, the at least one light source emits light in at least one of an IR spectrum, an NIR spectrum, and an UV spectrum to irradiate a cured adhesive within the patient's mouth.
• In one embodiment, the at least one light source includes a first light source for the IR or NIR spectrums and a second light source for the UV spectrum.
• In one embodiment, the light device further comprises a source of blue light that is capable of emitting light in a blue portion of a visible light spectrum to cure an adhesive with the patient's mouth.
• In one embodiment, the at least one light source is capable of producing an irradiance of 50 mW per cm²to 250 mW per cm².
• In one embodiment, the at least one light source is capable of producing an irradiance that does not heat a cured adhesive within the patient's mouth.
• In accordance with the principles of the present invention, a method of debonding an orthodontic appliance from a tooth comprises exposing an adhesive secured to the tooth to incoherent actinic radiation that reduces a bond strength of at least a portion of the adhesive and separating the orthodontic appliance from the tooth at the portion of the adhesive having reduced bond strength.
• In one embodiment, exposing the adhesive to actinic radiation includes exposing a plurality of orthodontic appliances simultaneously to the actinic radiation.
• In one embodiment, exposing the adhesive to actinic radiation includes exposing the adhesive to radiation in at least one of an IR spectrum, an NIR spectrum, and an UV spectrum.
• In one embodiment, exposing the adhesive to actinic radiation includes exposing the adhesive to actinic radiation in each of an IR spectrum and a UV spectrum or in each of an NIR spectrum and a UV spectrum.
• In one embodiment, prior to exposing, the method further comprises applying the adhesive to one of the tooth and the orthodontic appliance, affixing the orthodontic appliance to the tooth via the adhesive, and exposing the adhesive to a different spectrum of radiation from the incoherent actinic radiation to bond the orthodontic appliance to the tooth.
• In one embodiment, following exposing the adhesive to the actinic radiation, the method further comprises reorienting the orthodontic appliance relative to the tooth, and after reorienting, repeating the exposing of the adhesive to the different spectrum of radiation to bond the orthodontic appliance in a different orientation on the tooth.
• In one embodiment, separating includes generating sonic or ultrasonic vibrations and exposing the adhesive to the vibrations.
• In one embodiment, exposing the adhesive to the vibrations occurs simultaneously with exposing the adhesive to the actinic radiation.
• In one embodiment, during exposing the adhesive to the vibrations, the method further comprises applying a fluid to the tooth.
• In one embodiment, separating occurs during exposing.
• In one embodiment, separating occurs under the influence of gravity.
• In one embodiment, the method further comprises impinging a fluid on the tooth during separating.
• In one embodiment, separating includes applying one or both of a tensile force or a shear force on the adhesive.
• In one embodiment, applying includes pulling on one or both of an orthodontic bracket or an archwire to separate the orthodontic bracket from the tooth.
• In one embodiment, prior to exposing the method further comprises coupling a shell to the orthodontic appliance.
• In one embodiment, the shell defines a cavity and coupling includes placing the orthodontic appliance into the cavity.
BRIEF DESCRIPTION OF THE DRAWINGS
• The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a detailed description given below, serve to explain the principles of the invention.
• FIG. 1 is a perspective view of a light device according to one embodiment of the invention.
• FIG. 2 is a perspective view of a tip structure of the light device shown inFIG. 1.
• FIG. 3A shows a set of orthodontic brackets with individual brackets attached to the teeth of a patient.
• FIG. 3B is a perspective view of attachments for use with an aligner to facilitate orthodontic treatment.
• FIG. 4 is a cross-sectional view taken along section line4-4 ofFIG. 3A.
• FIG. 5 is an enlarged view of an encircledarea4 ofFIG. 4 according to one embodiment of the invention.
• FIG. 6 is an enlarged view of an encircledarea4 ofFIG. 4 according to one embodiment of the invention.
• FIG. 7 is an enlarged view of the encircledarea4 ofFIG. 4 according to one embodiment of the invention.
• FIG. 8 is an enlarged view of the encircledarea4 ofFIG. 4 according to one embodiment of the invention.
• FIG. 9A is a schematic representation of one application of the light device ofFIG. 1 for irradiating a bond between an orthodontic bracket and a tooth.
• FIG. 9B is a schematic representation of one application of the light device ofFIG. 1 for irradiating a bond between an orthodontic bracket and a tooth.
• FIG. 10A is an elevation view of a light device according to one embodiment of the invention.
• FIG. 10B is a schematic representation of one application of the light device ofFIG. 10A shown irradiating a bond between an orthodontic bracket and a tooth.
• FIG. 11 is a perspective view of a tip portion for use with the light device ofFIG. 1.
• FIG. 12 is a schematic representation of one application of the tip portion shown inFIG. 11 for irradiating a preselected number of teeth according to one embodiment of the invention.
• FIG. 13 is a perspective view of a light device according to one embodiment of the invention for irradiating an entire jaw.
• FIG. 14 is a perspective view of the light device according to one embodiment of the invention for irradiating an entire jaw.
• FIG. 15A is an elevation view of a light device according to one embodiment of the invention.
• FIG. 15B is an enlarged view of a tip structure of the light device shown inFIG. 15A.
• FIGS. 16A-16C are schematic partial cross-sectional views of one embodiment of a light device.
• FIGS. 17A-17C are schematic partial cross-sectional views of one embodiment of a light device.
• FIG. 18 is a schematic view of one embodiment of a light device.
• FIG. 19 is a perspective view of one embodiment of a light device.
• FIG. 20A is an elevational view of one embodiment of a light device.
• FIG. 20B is a perspective view of one embodiment of a light device.
• FIG. 21 is a photograph of a testing arrangement utilized to measure debonding force when debonding brackets from teeth.
DETAILED DESCRIPTION
• With reference toFIG. 1, an exemplary embodiment of alight device100 of the present invention is shown. Any single one of the light devices described herein may be used for irradiating an adhesive with light of various effective wavelengths as described below. In addition, the light devices may emit light while simultaneously producing mechanical vibration. By way of example only, thelight device100 may be used in orthodontic procedures in which an adhesive is used to bond an orthodontic appliance to one or more of the patient's teeth. The adhesive is responsive to actinic radiation emitted from thelight device100. In that regard, the clinician utilizes thelight device100 so that the clinician can more easily separate the orthodontic appliance from the tooth. Light from thelight device100 may break chemical bonds within the atomic structure of at least a portion of the adhesive. A working theory is that as the bonds break, the mechanical strength of the adhesive is reduced, which makes the adhesive more susceptible to intentional application of an applied force to remove the orthodontic appliance from the tooth. Where the adhesive includes a polymer, weakening the adhesive may be by a depolymerization process. The weakening process alternatively may be described as a decomposition process. In one embodiment, depolymerization reduces a bond strength between an orthodontic appliance and a tooth surface. Where thelight device100 also produces mechanical vibration, the simultaneous combination of light and vibrational energy may cause the orthodontic appliance to dislodge from the tooth. According to another embodiment, the clinician may utilize thelight device100 to both bond and debond an orthodontic appliance from a tooth. In that regard, thelight device100 may have a dual mode capability.
• To these and other ends, as shown inFIG. 1, thelight device100 includes ahousing102, which forms ahandle104. The clinician may grasp thehandle104 to utilize thelight device100 during patient treatment. The clinician may removably couple atip structure106 to thehandle104 at one end according to thearrow108 inFIG. 1. Although not shown, thehandle104 may include a socket that removably receives thetip structure106. Light (schematically shown with arrows110) is emitted from thetip structure106 when positioned in a patient's mouth. Thetip structure106 is shown separated from the handle inFIG. 2 and may therefore be autoclaved separately from thehandle104 or thetip structure106 may be a disposable item. Onetip structure106 may be utilized per patient per visit. This advantageously eliminates the need for sterilization between patients. As is described below, the clinician may couple other tip structures to thehandle104 depending on the number of teeth and orientation of a light source relative to the orthodontic appliance during irradiating of selected adhesive bonds. Thus, thehandle104 may be a universal component in a set of orthodontic devices with one handle and multiple, interchangeable tip structures described herein.
• The clinician may cause thelight device100 to selectively generate and emit electromagnetic radiation (illustrated by arrows110) from thetip structure106 to irradiate adhesive bonds. To that end, thelight device100 also includes suitable control electronics (not shown) with at least oneexternal control112 that may include a plurality of buttons, switches, or other suitable manual controls for controlling thelight device100. Selecting one of theexternal controls112 permits the clinician to control the emission of radiation from thetip structure106. Thecontrols112 may include on-off controls as well as means for selection of one or more wavelengths of light or types of light (e.g., ultraviolet (UV) spectrum, a blue portion of a visible light spectrum, infrared (IR) spectrum, and near infrared (NIR) spectrum) that are emitted from thetip structure106. Each of these spectrums of light may produce a different effect on an adhesive. A combination of wavelengths from the UV and IR/NIR spectrums may also be emitted from thelight device100. The clinician may therefore select a particular result by selecting a wavelength of light to be emitted from thelight device100 via thecontrols112.Other controls112 may include a timer and wattage selection. As is described below in conjunction withFIGS. 9A-15B, the clinician may insert thetip structure106 into the patient's mouth to a location at which an adhesive is located and then operate theexternal controls112 so that thelight device100 emits radiation from thetip structure106 toward an adhesive.
• With continued reference toFIG. 1, in one exemplary embodiment, ashield122 is coupled to thehandle104 and may alternatively be coupled to thetip structure106. Theshield122 may be transparent to visible light but may attenuate or block radiation that is emitted from thetip structure106 and that reflects from the patient's mouth toward the clinician. As such, the clinician may be able to view the treatment area in the patient's mouth through theshield122 though any radiation that strikes the patient's teeth and is reflected or scattered in a direction toward the clinician may be at least partially blocked by theshield122.
• With reference now toFIG. 2, in one embodiment, thetip structure106 includes aproximal end114 at which thetip structure106 is removably coupled with the handle104 (FIG. 1) and adistal end116 that is placed within the mouth of a patient for irradiating an adhesive. Thedistal end116 may include alight source120. By way of example, the light source may include one or more LEDs, one or more polymer-light emitting electrochemical cells (LECs). LEDs are commercially available from Osram Sylvania of Wilmington, Mass; Excelitas Technologies Corp. of Waltham, Mass; and Kodenshi Corp. of South Korea. These LEDs have a peak emission wavelength of from 810 nm to 860 nm. For example, Osram manufactures the SFH 4253 LED with a peak emission wavelength of 860 nm. The LECs may be designed in numerous shapes and may additionally use quantum dots to select specific wavelengths to be applied. Thelight source120 produces incoherent radiation and so, in one embodiment, is not a laser. There may be one light source for each of the spectrums selectable by the clinician. The clinician may operate at least one of thelight sources120 at a time to selectively emit one or more wavelengths of light or light in one or more light spectrums.
• Alternatively, thelight source120 may be remote from thetip structure106. For example, thelight source120 may be housed within thehandle104. Waveguides may couple thelight source120 in thehandle104 through thetip structure106 so that light is transported from thehandle104 through thetip structure106 and is emitted from thedistal end116. Even further, thelight source120 may be remote from thelight device100, that is, not in thehandle104, though thelight device100 may be coupled to the remote light source via one or more waveguides, such as a fiber optic, that extends from thehandle104 to the remote source.
• Thelight source120 is controllable via thecontrols112 to emit light in at least one of the IR spectrum (i.e., wavelengths of about 700 nm to about 1 mm), NIR spectrum (i.e., wavelengths of about 780 nm to about 2500 nm), a blue portion of the visible light spectrum (e.g., wavelengths of 450 nm to 495 nm), and the UV spectrum (i.e., wavelengths of about 10 nm to about 400 nm). Thelight source120 may include separate sources for each of the IR, NIR, and UV spectrums. For example, thelight source120 may be a plurality of LEDs with different LEDs for any two or all three of the IR spectrum, NIR spectrum, and the UV spectrum.
• Although not shown inFIGS. 1 and 2, thelight device100 may be coupled to a charger base during nonuse so that a power source (e.g., a battery) within thelight device100, such as within thehandle104, may be recharged. Exemplary charger base electronics as well as additional features of a dental light device are further described in commonly owned U.S. Pat. No. 9,072,572, which is incorporated by reference herein in its entirety.
• Thelight device100 may be capable of producing light of sufficient total radiant flux to irradiate an adhesive and reduce its bond strength. Total radiant flux is equal to the total radiated power output integrated over the entire emission spectrum of the light source and over all spatial orientations. In other words, total radiant flux is the total amount of light energy emanating from the light source each second and is measured in Joules per second or Watts (W). With reference to the LEDs described herein, for example, an Osram FH 4253 LED with a peak emission wavelength of 860 nm that produces about 10 mW at an applied voltage of 1.45 V with a lens area of about 0.045 cm²outputs a dosage sufficient to break chemical bonds when the adhesive is exposed for about 10 minutes when the LED is held at a distance of 0.5 cm to 1 cm. And, as another example, LEDs that produce a wavelength of 940 nm at 2.75 W (measured at a distance of 0.5 cm to 1 cm) provide a dosage sufficient to break chemical bonds in about 30 seconds, for example, from 26 seconds to 34 seconds, as is described below.
• This power output translates into dosage measured in energy per unit area (e.g., Joules per cm²). The dosage is the product of the irradiance and exposure time as applied to a surface of the adhesive at the tooth-adhesive interface, or at the bracket-adhesive interface. This may be represented by the equation:
• $\mathrm{Dosage}\left(\frac{J}{{\mathrm{cm}}^2}\right)=\mathrm{Irradiance}\left(\frac{\mathrm{mW}}{{\mathrm{cm}}^2}\right)*\mathrm{Exposure}\mathrm{time}\left(s\right)$$\mathrm{where}$$\mathrm{Irradiance}\left(\frac{\mathrm{mW}}{{\mathrm{cm}}^2}\right)=\frac{\mathrm{Radiant}\mathrm{Flux}\left(\mathrm{mW}\right)}{\mathrm{Area}\mathrm{of}\mathrm{recieving}\mathrm{surface}\left({\mathrm{cm}}^2\right)}$
• Thelight device100 may include an aperture or window (not shown) through which light from the light source exits the device. The aperture limits the output of the light source to a specific direction so the radiant flux in the above equation may reflect the total radiant flux of the light source as portioned by the aperture. Although not indicated in the equations, a distance between the receiving surface and thelight device100 also plays a role in the determining the radiant flux at the receiving surface relative to the total radiant flux because light may be lost, e.g., absorbed, between the light source and the receiving surface. The reduction in bond strength from exposure to the selected light may occur at a rate sufficient to permit a clinician to remove an appliance bonded to the tooth after a few minutes (e.g., less than 10 minutes) or even a few seconds (e.g., less than 60 seconds). Removal of the appliance may occur without patient pain or discomfort. By way of example only, the appliance may fall off the patient's tooth under the force of gravity after the bond between the tooth and the appliance is exposed to radiation produced by thelight device100. That is, no force other than gravity is applied to the appliance. Alternatively, as is described below with reference toFIGS. 15A-20B, the clinician may apply an external mechanical force (e.g., a shear force), such as with a tool or finger, to remove the orthodontic appliance after the bond is sufficiently weakened.
• While the selection of a particular range of light wavelengths promotes debonding of the orthodontic appliance by a depolymerization process, the irradiance of that selected light source may at least partially determine the rate at which the strength of the adhesive bond decreases. In an exemplary embodiment, thelight device100 is capable of an irradiance of at least about 77 mW per cm²to about 200 mW per cm²over the course of a few seconds or a few minutes (less than 10 minutes). Embodiments of the invention are not limited to this range of irradiance, for example, it is contemplated that an irradiance of up to 1 W per cm²is usable. Not being bound by theory, increasing the radiant flux (e.g., increasing the total radiant flux of the light source) of thelight device100 may reduce the time required to debond an orthodontic appliance from the patient's tooth. This reduction is believed to be achieved by increasing the rate of bond cleaving, and thus weakening the strength of the adhesive between the tooth and the appliance. For example, at an output power of about 3 W, it may take about 10 minutes of exposure to sufficiently reduce the bond strength of the adhesive to the point at which the clinician may remove an orthodontic appliance from the patient's teeth with only light mechanical debonding forces. These forces are less than the forces typically applied with a pair of pliers, which is at least 7 MPa. In one embodiment, the clinician activates thelight device100 to expose the adhesive10 to light of a selected wavelength and the adhesive bond strength is reduced to less than 7 MPa in 10 minutes or less. Increasing the power output to 5 W may reduce an exposure time to 5 minutes or less. And, further increasing the output power to 15 W may sufficiently reduce the bond strength in 10 seconds or less.
• As described about, thelight device100 may have dual capability, that is, thelight device100 may be utilized in both bonding and debonding of appliances to the patient's teeth with an adhesive. According to an exemplary embodiment, because the adhesive depolymerizes, high output power (e.g., 100 W or more) is not required to heat the adhesive. In that regard, thelight device100 exposes the adhesive to light in the range of 50 mW per cm²to 250 mW per cm²so that cleavage and debonding occurs at or near (within 2° C.) of normal body temperature. There is no change in viscosity of the adhesive due to a measurable temperature increase.
• To that end, with reference now toFIGS. 3A-8, in one embodiment, a clinician may utilize anorthodontic adhesive system10 to adhere an orthodontic device to a patient's tooth. The clinician may utilize the light devices described herein for depolymerizing at least a portion of theadhesive system10. While depolymerization is described, it will be appreciated that other forms of decomposition of at least a portion of the adhesive may occur, that is, embodiments of the invention are not limited to breaking of bonds in a polymer. As described herein, theorthodontic adhesive system10 includes an engineered protein. By way of example only, as shown inFIG. 3A, anorthodontic bracket12 may be used in an orthodontic procedure. Oneorthodontic bracket12 may be affixed to each of a plurality ofteeth14 with theorthodontic adhesive system10. Theorthodontic bracket12 defines a substantially transversely disposedarchwire slot16, which receives anarchwire20. Theorthodontic bracket12 may be adhesively secured to an exterior facing surface22 (i.e., the labial surface) of eachtooth14 with theorthodontic adhesive system10. Although not shown inFIG. 3, theorthodontic adhesive system10 may be between each of theorthodontic brackets12 and the correspondingtooth14. Whilebrackets12 are shown and described herein, embodiments of the present invention may be utilized to bond other orthodontic appliances to the patient's teeth. For example, theorthodontic adhesive system10 may form attachments, shown inFIG. 3B.
• Analigner60 withcorresponding bulges64 is configured to engageattachments10 for orthodontic treatment. By way of additional example, theadhesive system10 may be utilized to bond a lingual retainer and bite turbos, to name a few, to the patient's teeth.
• With reference toFIGS. 3A-9B, thelight device100 may be utilized to at least selectively debond one or more the orthodontic brackets12 (FIG. 3A) or attachments10 (FIG. 3B) from a corresponding one or more of the patient'steeth14. In one embodiment, thelight device100 may be utilized both during bonding of onebracket12 to one of the patient'steeth14 and during debonding of thebracket12 from the tooth. Similarly, referring toFIG. 3B, thelight device100 may be used both during bonding of theattachment10 to one of the patient'steeth14 and during debonding of theattachment10 from thetooth14.
• With reference toFIGS. 4-8, theorthodontic adhesive system10 may include asingle layer18 of one or more components as is shown inFIG. 8 or a plurality oflayers24 of individual, separately-applied components, as is shown inFIGS. 4-7. While the plurality oflayers24 appear to be illustrated in approximately equal parts inFIGS. 5-7, this is not necessary. Although not shown, the plurality oflayers24 of individual, separately-applied components may be of differing dimensions and thicknesses in relation to each other. Thelayers18,24 include one or more components that are configured to bond to one of thetooth surface22 or anorthodontic appliance12 or form a bond between other components in a sandwich-like composite construction. An exemplary orthodontic adhesive is described in commonly owned U.S. application Ser. No. 15/699,230 which is expressly incorporated by reference herein in its entirety. Other exemplary adhesives include those disclosed in U.S. Pub. Nos. 2016/0160097 and 2017/0217999 which are each incorporated by reference herein in their entirety. When attached torespective teeth14 with theorthodontic adhesive system10, thebrackets12 and thearchwire20, or thealigner60 andattachments10, collectively provide orthodontic treatment.
• Theorthodontic adhesive system10 may eliminate one or more of the tooth preparation steps. For example, theorthodontic adhesive system10 may not require one or more of the cleaning and acid etching steps, described above, though thesystem10 secures theorthodontic bracket12 to a correspondingtooth14 or is formed in to anattachment10. Furthermore, thelight device100 improves removal of anorthodontic bracket12 adhered to a tooth with theorthodontic adhesive system10. In one aspect, embodiments of the light devices eliminate the need to apply mechanical force to debond thebracket12 from thetooth14, and so patients will not experience the discomfort during removal. Alternatively, theadhesive system10 permits reduced mechanical forces in debonding when the devices described herein are applied to theadhesive system10. Embodiments of the light devices described herein may be utilized during at least debonding of thebracket12 from the correspondingtooth14 or during removal of one or more of theattachments10. Debonding may include depolymerization/decomposition of chemical bonds in one or more of thelayers24.
• Following removal of theorthodontic bracket12 orattachment10, there will be minimal, if any, adhesive residue on thetooth14. Embodiments of the invention will therefore also eliminate or minimalize post-removal cleaning of theteeth14. The clinician may not need to restore the tooth surface to its pre-treatment condition and so the tooth may not suffer iatrogenic damage due to grinding or other abrasive processes. As another advantage to both the patient and clinician, thelight device100 facilitates reversible bonding and debonding of an appliance to thetooth14. That is, a bonding network of theorthodontic adhesive system10 is selectively activated (e.g., polymerized) with thelight device100 to bond and deactivated (e.g., depolymerized) with a light in a different spectrum from thelight device100 to debond theadhesive system10 from the surface of thetooth14. A clinician may then easily correct the orientation of a misplaced orthodontic appliance or attachment by selection of different wavelengths and exposing the adhesive to those wavelengths with thelight device100. In an exemplary embodiment, thelight device100 only facilitates debonding the orthodontic appliance from the tooth because theadhesive system10 is not capable of polymerizing following depolymerization.
• With reference toFIGS. 4-8, the catechol-like moiety and the functional monomer of the engineered protein adhesive of theorthodontic adhesive system10 may be tethered together to form at least a portion oflayer18,24 with the catechol-like moiety bonding to thetooth surface22. This moiety may facilitate adhesion of the monomer to thetooth surface22 in the absence of prior cleaning, etching, and drying thetooth surface22. By eliminating one or more of these preparation steps, embodiments of the invention significantly reduce chair time. The reduction in time to bond a single bracket to a tooth may be reduced by about 80%. For example, conventional preparation and adhesive may require as much as 4 minutes per tooth. Theadhesive system10 may reduce that to about 30 seconds per tooth. A typical bonding appointment takes from 2 to 3 hours of patient commitment. In accordance with embodiments of the present invention, a clinician may bond orthodontic appliances to a patient's teeth on the same day as an initial consultation. This is not commonly practiced because of the long chair time requirements associated with bonding orthodontic appliances to the patient's teeth using conventional techniques, adhesives, and systems. Moreover, the reduction in bonding time, and chair time associated therewith, results in reduced cost for the clinician while increasing potential profitability by increasing the clinician's capacity to see more patients.
• In any of the exemplaryadhesive systems10 shown inFIGS. 4-8, the monomer of the engineered protein adhesive adheres to thetooth surface22 and forms a base onto which the orthodontic device is ultimately attached. For example, and with reference toFIG. 5, in one embodiment, theorthodontic adhesive system10 may include four layers that collectively form thecomposite layer24. In that regard, theorthodontic adhesive system10 may include one or more separately appliedlayers26,28,30, and32 that collectively bond theorthodontic bracket12 to thetooth14. Each of the components in thelayers26,28,30,32 bonds with components in the other layers and/or with thetooth14 or theorthodontic bracket12.
• InFIG. 5, thelayer26 is in direct contact with thetooth surface22. Thelayer26 includes a monomer of an engineered mussel protein that has a catechol-like moiety. By way of example, the monomer of the engineered mussel protein includes catechol methacrylate. Unlike some conventional orthodontic sealants, the catechol-like moiety forms adhesion networks through hydrogen bonding and metal-ligand complexes with hydroxyapatite without one or more of cleaning, etching, or drying preparation steps. Additionally, the catechol-like moieties may undergo Michael addition with collagen in enamel or in dentin to chemically bond thelayer26 to thetooth surface22.
• Although not shown inFIG. 5, by way of example only, thelayer26 may be on the order of about 100 nanometers thick. Thelayer26 may be thicker or thinner than 100 nanometers and may depend on application technique and viscosity of thelayer26. Thelayer26 may be very thin relative to the overall thickness of the joint formed by theadhesive system10 between thebracket body12 andtooth14. Thelayers28,30, and32 may be separately applied on the monomer oflayer26 attached to thetooth surface22.
• Thelayer28 may be in direct contact and may chemically bond with the catechol-like containing monomer that forms thelayer26 before or after that layer cures. In the embodiment shown inFIG. 5, thelayer28 may include a nitrocatechol and nitrocatechol derivative-containing compound (described below) that bonds to the dried monomer that forms thelayer26. While not being restricted to any particular thickness, in one embodiment, thelayer28 is about 100 nm to about 500 nm. In an exemplary embodiment, thelayer28 denatures when exposed to a specific wavelength of light. Thus, at the end of treatment, the clinician can utilize thelight device100 to expose thesystem10 to that light to denaturelayer28. As a result, that layer dissolves and releases theorthodontic bracket12 or remainder of theattachment10 from thetooth14. The clinician then easily removes theorthodontic bracket12 or remainder of theattachment10. The patient or clinician may removeresidual layer26 with a normal tooth brush.
• In one embodiment, and with reference toFIG. 5, a sealant may form layer30. The layer30 may be in direct contact and may chemically bond with the nitrocatechol and nitrocatechol derivative-containing compound that forms thelayer28 before or after that layer cures. In the embodiment shown inFIG. 5, the layer30 may be an acrylate-based resin sealant that bonds to thelayer28. In one embodiment, the sealant forming the layer30 is a commercially available orthodontic sealant, such as Ortho Solo™, available from Kerr Corporation of Orange, Calif.
• As shown, the layer32 may then be directly applied on the layer30 in a separate application. The layer32 chemically bonds to the layer30 and also mechanically bonds to theorthodontic bracket12. The layer32 may be preshaped to form the bulk of theattachment10. By way of example only, the layer32 may include a resin, such as a methacrylic resin, which may include an acrylate and/or a methacrylate moiety that chemically bonds with the acrylate-based resin sealant of layer30 when exposed to a preselected wavelength of light. In one embodiment, thelight device100 is also capable of producing the preselected wavelength of light necessary to initiate curing of the adhesive10 and, in particular, the layer32. When applied, the layer32 may include a photo-initiator to facilitate curing of the layer32. In one embodiment, the resin is a commercially available orthodontic adhesive, such as Grengloo® or Blugloo, each of which is commercially available from Ormco Corporation of Orange, Calif.
• In the case of the layer32, which may include the photo-initiator, theorthodontic bracket12 may be pressed against thecomposite layer26,28,30, and32 shown inFIG. 5. The adhesive layer32 may then be cured by activating thelight device100. For example, as is shown inFIG. 9A, the clinician may position thetip structure106 to irradiate the layers according to110 with visible blue light (e.g., wavelengths of 450 nm to 495 nm). This photo-curing process cures at least the layer32. By way of further example, each of thelayers26,28,30, and32 may be cured at the same time or at different times. Although not shown, the timing of each cure depends on the preferences of the clinician. A clinician may prefer to partially cure thelayer26 to make it tackier and then apply the remaining layers with a final cure of each of thelayers26,28,30, and32 together. When thelayers26,28,30, and32 are cured, theorthodontic adhesive system10 bonds theorthodontic bracket12 to the tooth surface22 (FIG. 3A) or forms an attachment10 (FIG. 3B).
• In the exemplary orthodonticadhesive systems10 shown inFIGS. 5, 6, and 7, the functionalities described above with regard to thelayers26,28,30, and32 may be combined in fewer than four layers. For example, the functionality oflayers28 and30 may be combined resulting in a three-layer system (FIG. 6). By way of further example, a two-layer system (FIG. 7) may combine the functionality of the catechol-like moiety oflayer26 with a sealant, such as that described above in layer30, which may include a nitrocatechol and nitrocatechol derivative-containing compound. In this case, the functionality oflayers26,28, and30 ofFIG. 5 is present in a layer40 ofFIG. 7. Thus, with reference toFIG. 7, the layer40 is applied to thetooth surface22. The catechol-like moiety of the layer40 may form adhesion networks through hydrogen bonding and metal-ligand complexes with the enamel at thesurface22 without one or more of cleaning, etching, or drying.
• With reference toFIG. 7, the layer42 may be similar to the layer32 ofFIG. 5. Specifically, the layer42 may include a resin, such as a methacrylic resin, which may include an acrylate and/or a methacrylate moiety that chemically bonds with a resin of layer40. InFIG. 8, theorthodontic adhesive system10 includes thesingle layer18 having components which combine the functions of thelayers26,28,30, and32 described above. By way of example, a catechol-like moiety of thelayer18 may form adhesion networks through hydrogen bonding and metal-ligand complexes with enamel without one or more of cleaning, etching, or drying thetooth surface22. And, thelayer18 may include a debonding compound and a resin, such as a methacrylic resin, which may include an acrylate and/or a methacrylate moiety that chemically bonds with the acrylate-based resin sealant and forms a bond between theorthodontic adhesive system10 and thebracket12. The figures are not drawn to scale. Thus, whilelayers26,28,30, and32 inFIG. 5;layers26,30, and32 inFIG. 6; layers40 and42 inFIG. 7; andlayer18 inFIG. 8, are depicted as being uniformly thick in approximately equal thicknesses, the layers are not limited to the relative ratios of the thicknesses shown. The thickness of each layer can vary independently of the other layers.
• By way of example, the photocleavable moiety of theorthodontic adhesive system10 may be any moiety that is capable of being broken when exposed to light in at least one of the IR spectrum (i.e., wavelengths of about 700 nm to about 1 mm), NIR spectrum (i.e., wavelengths of about 780 nm to about 2500 nm), light in the UV spectrum (i.e., wavelengths of about 10 nm to about 400 nm), or a combination of IR/NIR and UV spectrum. Photocleavable moiety may include photocleavable bis-methacrylate. The bis-methacrylate chain length may be modified to optimize the debonding parameters. For example, lengthening the polymer chain may reduce the time for debonding. Exposure to, for example, IR light may depolymerize theorthodontic adhesive system10 and so aid in the debonding of thebracket12 from thetooth surface22. It is believed that IR light is advantageous because it passes through both hard (e.g., tooth) and soft (e.g., lips, cheek, and tongue) tissues. The clinician may more easily expose theorthodontic adhesive system10 to IR light todebond brackets12 from theteeth14. Alternatively, the photocleavable moiety may be broken when exposed only to light in the UV spectrum.
• Once treatment is complete, in one embodiment, the clinician utilizes thelight device100 to debond theorthodontic brackets12 by activating thelight device100 and exposing the adhesive to light in the IR spectrum from thelight device100. Alternatively, thelight device100 may produce light in the UV spectrum. The orthodontic bracket(s)12 may fall off or only require a slight application of force for removal following exposure to the light. It is thought that any force application in combination with light exposure would be substantially less than conventional forces required to debond orthodontic devices from teeth. In addition to reducing the bonding forces, debonding may minimize or completely eliminate the need for grinding away residual adhesive once the orthodontic device is removed. In cases where conventional adhesives needed to be removed mechanically (i.e., be ground off), patient discomfort from mechanical removal is eliminated using the adhesives in combination with the light devices described herein. Also, emergency appointments may be minimized because the adhesives described herein tend to provide higher adhesion strength. For example, bond strength may reach about 15 MPa or more such that accidental debonding may be minimized. These bond strengths may be achieved while also reducing the time it takes to intentionally debond the orthodontic device.
• As applied to the embodiment ofFIG. 5, for example, when exposed to IR light or UV light, thelayer28 may denature, in which case thelayer28 may break down so that thebracket12 and the layers30 and32 may be released from thetooth14. Following debonding, thelayer26 may remain on thetooth surface22. However, the patient may removelayer26 by brushing their teeth with toothpaste and a toothbrush. Thus, during treatment, a dental bracket may be strongly adhered to the teeth of a patient when desired, but then may also be easily removed from the teeth when treatment is completed or when the device needs repositioning or replacement, by exposing the adhesive to IR/UV light from thelight device100.
• With regard to debonding theorthodontic bracket12 from thetooth14, as is illustrated inFIG. 9B, thelight device100 may be positioned to irradiate an adhesive bond between theorthodontic bracket12 and thetooth14. Thelight device100 produces one or more wavelengths or ranges of wavelengths of light that interact with a photocleavable moiety in the adhesive10. By way of example only, and not limitation, wavelengths in the UV spectrum or in the IR spectrum or a combination of UV and IR spectrums may react with the adhesive10 to reduce its bond strength. Not being bound by theory, this reaction may be by a photocleaving process between the light and a component in one or more of thelayers18,26,28,30,32,40, and42 described above and shown inFIGS. 5-8. In one embodiment, photocleaving occurs between thelayer26 and thelayer28 or photo-cleaving may occur in thelayer28 shown inFIG. 5. The clinician may utilize a similar procedure for debonding theattachment10 ofFIG. 3B from selectedteeth14.
• Depending upon the wavelength utilized during debonding and the location of the orthodontic appliance, the clinician may position thetip structure106 lingually of thetooth14. For a lingually located appliance, thetip structure106 may be positioned to directly irradiate the appliance and/or the attachment. Alternatively, the tip structure may be positioned so that radiation from thelight device100 passes through thetooth14. It will be appreciated that human teeth are transparent or translucent to certain wavelengths of light so that debonding by irradiating the adhesive10 through thetooth14 is only appropriate for those wavelengths. One advantage of irradiating the adhesive10 through thetooth14 is that it may uniformly expose the adhesive bond to the light from thetip structure106. That is, the entire interface between the tooth and the bond may be uniformly irradiated and so increase the probability that the adhesive is uniformly weakened. This may produce a uniform release of thebracket12 orattachment10 from thetooth14.
• For debonding applications in which thelight device100 is positioned lingually of the tooth, an alternative tip structure is shown inFIGS. 10A and 10B. Atip structure130 may be coupled to thehandle104 in a manner similar to thetip structure106 shown inFIGS. 1 and 2. In one aspect of thelight device100, thetip structures106,130 may be interchangeable. With reference toFIG. 10A, thetip structure130 may have an L-shape in which afirst leg132 extends from thehandle104 and asecond leg134 is generally perpendicular to thefirst leg132. As is shown inFIG. 10B, the L-shaped configuration permits more convenient placement of theleg134 lingually of atooth14, such as lingually of amolar14 shown inFIG. 10B.Light110 emitted from thelight source120 may be directed from thetip structure130 through thetooth14 to irradiate the bond between theorthodontic bracket12 and thetooth14. As is described above, thebracket12 may then fall off thetooth14 or be gently mechanically removed, such as with the device shown inFIGS. 15A and 15B (described below), a pair of pliers, tweezers, or with fingers.
• For wavelengths that will not fully penetrate through thetooth14, thetip structure106 may be positioned similar to that shown inFIG. 9A. The clinician may move thetip structure106 relative to thebracket12 to more uniformly irradiate the adhesive10 in this orientation. Once the adhesive10 is sufficiently weakened, thebracket12 may be forcibly removed from thetooth14 or thebracket12 may fall off thetooth14, as is shown inFIG. 9B. Thus, thelight device100 in combination with theadhesive system10 disclosed herein may provide a noncontact technique for removal of orthodontic appliances from teeth at the end of treatment and/or during treatment so that thebracket12 may be repositioned or a different bracket may be attached to thetooth14. The light devices described herein may offer a pain free method of removing orthodontic appliances. No physical contact between a tool and the orthodontic appliance may be required to remove the appliance. In that case, the actinic radiation may be sufficient to separate the orthodontic appliance from the tooth. Patients no longer need to fear removal following or during orthodontic treatment.
• In addition, one or more of thelayers18,26,28,30,32,40, and42 may remain attached to thebracket12 during removal. This is schematically shown inFIGS. 9B and 10B where the removedorthodontic bracket12 includes adhesive10. Advantageously, little or no adhesive residue may remain on thetooth14. In those cases, the clinician dispenses with any post-debonding cleanup of the tooth surface. For example, the clinician may not have to grind away residual adhesive following debonding. By way of example, a typical orthodontic bracket may be bonded to the tooth and achieve a shear strength of from 10 MPa to 20 MPa. IR or UV light exposure may reduce that shear strength to 1 MPa or less. Bond strength may be reduced to less than 20% of the bond strength observed during orthodontic treatment. Shearing the adhesive with application of light shear forces may occur at or near the tooth surface so that post debonding cleanup is mostly avoided.
• Thelight device100 withtip structure106 or130 shown inFIGS. 1, 9A, 9B, 10A, or10B may be focused on a single tooth and so may be utilized to provide treatment to an adhesive bond between one tooth and one orthodontic appliance. This treatment may be achieved on a one-at-a-time basis and may be beneficial in situations where the clinician may need to debond a single bracket from a tooth so that the bracket may be re-bonded to the tooth in a different location or perhaps the bracket design may be changed on that particular tooth. Additional adhesive bonds may be treated by directing the light110 from thetip structure106,130 to other bonds on a bond-by-bond basis. However, other tip structures may be utilized to irradiate multiple teeth or the patient's entire jaw in a single exposure.
• In that regard, and with reference toFIGS. 11-14, 17A-18, and 20A-20B various tip structures are disclosed which may be utilized with thehandle104 shown inFIG. 1 and so may be used interchangeably with thetip structures106 and130, described above. In general, the devices and tip structures described herein address the needs of the clinician from a comfort standpoint. That is, while the patient's comfort is of utmost concern, the ergonomics of the clinician are also a consideration. Devices described herein reduce or eliminate discomfort for the clinician. Thus, the clinician is less likely to fatigue and is more likely to repeatedly utilize the device without need for a break. To that end, the devices described herein are designed to access difficult areas of a patient's mouth, including between a cheek and a labial surface of the teeth. The devices locate the light sources to irradiate adhesive without requiring the clinician to hold the device at an uncomfortable angle or the patient may hold the device. In either case, the device may eliminate poor ergonomics for the clinician.
• With reference toFIGS. 11 and 12, atip structure140 is shown and is capable of irradiating multiple teeth (and adhesive bonds) simultaneously. In the exemplary embodiment shown, thedistal end116 of thetip structure140 includes ahousing142 within which a plurality oflight sources120 orlenses136 are located. While twolight sources120 are shown, it will be appreciated that thehousing142 may include three or more light sources or lenses. Further, the number oflight sources120 orlenses136 may be equivalent to the number of orthodontic appliances and/or teeth being irradiated. Embodiments of the invention are not limited to any relationship, such as a one-to-one relationship, between the number of teeth and the number oflight sources120 orlenses136.
• As shown, thehousing142 includesshields144 and146 that generally extend distally past thelight sources120 orlenses136. When the clinician positions thetip structure140, theshields144 and146 may be positioned between thetooth150 on the one side and152 on the opposing side, respectively. In this exemplary embodiment, twoteeth154 and156 are selected for exposure and are isolated from theteeth150 and152. When thelight device100 is activated, light may be prevented from directly impinging upon each of theteeth150 and152. Theshields144,146 may enable the clinician to selectively debond an appliance or attachment from one or both of theteeth154 and156 while reducing the radiant energy impinging on adjacent orthodontic appliances and attachments, such as onteeth150 and152, and their associated adhesive bonds. Advantageously, thetip structure140 may allow the clinician to selectively debond while avoiding degradation of adjacent adhesive bonds.
• With reference toFIGS. 13 and 14, other embodiments of a tip structure are shown. These tips reduce fatigue by placing the light source directly adjacent each of the orthodontic appliances. As shown, the tip structures include light sources to irradiate an entire jaw simultaneously and so eliminate removal of one appliance at a time. Generally, each of the tip structures shown may be utilized at the end of treatment when all the orthodontic appliances on one of the patient's jaws are to be removed from the patient's teeth. That is, the tip structures are configured to irradiate each of the adhesive bonds between an orthodontic bracket and a corresponding one of the patient's teeth. The clinician or the patient may removemultiple brackets12, even an entire arch ofbrackets12, with a single exposure to wavelengths of a selected light spectrum.
• To that end, and with reference toFIG. 13, atip structure160 may be configured to be removably coupled to the handle104 (shown inFIG. 1) at aproximal end162 similar to theproximal end114 of the tip structure106 (shown inFIG. 2). Thetip structure160 includes amouthpiece164 at adistal end166. Themouthpiece164 may be generally shaped according to a human jaw and has abite plate170 that is configured to go between the patient's upper and lower jaws and asidewall172 that is generally perpendicular to thebite plate170. When the patient bites on thebite plate170, thetip structure160 and handle104 are held in position without clinician assistance. Thesidewall172 includes multiple light sources120 (orlenses136 if the light source is remote from the sidewall172).
• As can be appreciated byFIG. 13, when thetip structure160 is inserted into the patient's mouth, thesidewall172 faces the lingual surfaces of all the patient's teeth. When activated, thelight sources120 irradiate attachments or the adhesive between each of the appliances and the corresponding teeth. After a predetermined time, the attachments/appliances may simply fall off the patient's teeth and be captured on the bite plate170 (e.g., when appliances are bonded to the patient's maxillary jaw). Thetip structure160 is an example of indirect debonding in which thetip structure160 does not directly contact the appliance. Indirect debonding is in contrast to direct debonding, which is described below with reference toFIGS. 16A and 16B.
• Alternatively, in one embodiment of the invention, the clinician may removemultiple brackets12, even an entire arch ofbrackets12, simultaneously by use of thearchwire20. The clinician may expose theorthodontic adhesive system10 to IR light or UV light, such as with thetip structure160. Once at least a portion of theorthodontic adhesive system10 denatures, the clinician may then pull on thearchwire20 while it is still engaged with eachbracket12 on the arch (as shown inFIG. 3A). Thebrackets12 detach while still coupled to thearchwire20. In this way, the clinician may remove each of thebrackets12 with one pull on thearchwire20 in combination with use of thetip structure160. This process may leave no residual adhesive on theteeth14. As another advantage, this prevents unforeseen loss or ingestion of the individual brackets and can significantly reduce chair time, for example, by greater than 90%.
• Further in that regard, and with reference toFIG. 14, atip structure180 as shown. Thetip structure180 includes theproximal end162 so that it may be removably coupled to thehandle104 similarly to the other tip structures described herein. In contrast with thetip structure160 shown inFIG. 13, thetip structure180 is configured to emit radiation toward the labial surfaces of the patient's teeth. In that regard, thedistal end166 of thetip structure180 includes abite plate182 in the shape of a human jaw. Thebite plate182 may fit between the patient's upper and lower jaws. Similar to thetip structure160, when the patient bites down on thebite plate182, thetip structure180 remains in position without the clinician's assistance. Asidewall184 may extend generally perpendicular to thebite plate182 and include a plurality of light sources120 (orlenses136 for a light source remote from thedistal end166 of the tip structure180). As can be appreciated byFIG. 14, when thetip structure180 is inserted into the patient's mouth, thesidewall184 faces the labial surfaces of all the patient's teeth. When activated, thelight sources120 irradiate the adhesive between each of the appliances and the corresponding teeth. After a predetermined time, the appliances may simply fall off the patient's teeth and be captured on the bite plate182 (e.g., when appliances are bonded to the patient's maxillary jaw).
• Although not shown, as an alternative to the embodiments disclosed in the figures, in one embodiment, the tip structure includes a mat in which LEDs and/or a vibrational source are embedded. The mat may be rectangular or U-shaped. The tip structure lays or rests on the teeth. The mat is flexible and conforms to the teeth and orthodontic appliance upon urging of the practitioner or patient or under the influence of gravity. In this way, the mat forms a shell. Activation of the tip structure applies light and/or vibrational energy to the appliance and corresponding bond so that the mat produces a similar result as eithertip structures160,180.
• With reference now toFIGS. 15A and 15B, an exemplarylight device200 is shown. Thelight device200 is similar to thelight device100 shown inFIG. 1 and includes ahousing202 that defines thehandle204. Atip structure206, which may be in the form of a scaler, extends from one end of thehandle204 and afluid reservoir208 is removably coupled to thehandle204 at the opposing end. The clinician may fill thefluid reservoir208 with water for use as described below. Light may be emitted from thehousing202 via alight source210, which directs selected wavelengths of a light spectrum (indicated byarrows110 inFIG. 15B) toward the patient's teeth. Thelight source210 may be positioned adjacent thetip structure206 and direct light toward thetip structure206. Thus, the light and thetip structure206 may be used in combination during debonding. Thehousing202 may contain a light source, described above, or be a lens through which light may pass. The light source in that case may be within thehousing202 or be supplied from a remote light source that is coupled to the lens. Thehousing202 may also contain a sonic or ultrasonic generator (e.g., a piezoelectric device) coupled to thetip structure206. The clinician may then turn the generator on and off to control vibration of the tip structure206 (as is indicated by the arrows214). Scaler vibration may be in the sonic or ultrasonic range and may be measured in kilohertz. For example, the range may be from about 23 kHz to about 32 kHz. Thefluid reservoir208 may be fluidly coupled through thehousing202 to aport212 adjacent thetip structure206. Thelight device200 is configured to eject fluid from thefluid reservoir208 from theport212 toward thetip structure206 and thus may impinge upon the patient's teeth. This may be achieved by a pump or other means.
• During debonding of an orthodontic appliance, such as debonding an orthodontic bracket, the clinician may simultaneously expose the adhesive to light from thelight source210 according toarrows110 inFIG. 15B and then contact thetip structure206 with the orthodontic bracket. The clinician may touch the orthodontic bracket with thetip structure206 while exposing the adhesive to light110. Thetip structure206 is an example of direct debonding. The shear forces on the bracket may be sufficient to remove it from the patient's tooth. Alternatively, the clinician may apply additional mechanical energy by activating the vibration source so that thetip structure206 vibrates against the orthodontic bracket. In that regard, the clinician may selectively spray fluid (according toarrow216 inFIG. 15B) from thereservoir208 from theport212 toward the tooth. Advantageously, the fluid may act to cool the tooth during debonding and so may eliminate the possibility of patient discomfort due to heat in the tooth.
• In view of the above, one method to remove an orthodontic bracket from a tooth may be to utilize thelight device200 to apply 5,000 mW of NIR light (about 980 nm or about 940 nm) or UV light (about 395 nm or about 365) (as used herein with respect to wavelength “about” means plus or minus 5 nm) for at least about 5 seconds along with a low-speed vibration to the scaler portion of thetip structure206. It is believed that a layer, such as layer28 (shown inFIG. 5), exposed to a combination of light and mechanical vibration will break and so provide a consistent, predictable failure location. Ultimately, the adhesive bond may be reduced from a strength of about 20 MPa to about 1 MPa and the adhesive may be removed from the tooth with little or no residual adhesive on the tooth. As another example, one method of removing an orthodontic bracket includes irradiating an adhesive with light at 940 nm at 2.74 W in combination with ultrasonic vibration in the range of 28 kHz to 32 kHz. This produces a radiant flux of 204 mW. Exposure time is sufficient so that the adhesive receives a dosage of 423.7 J/cm². The combination of light and vibration is sufficient to remove the orthodontic appliance.
• In another exemplary method, an orthodontic bracket may be removed with thelight device200 by application of 10 W of UV light (e.g., at a wavelength of about 395 nm) and by contacting the orthodontic bracket with a low ultrasonic vibration tool. As another example in the UV spectrum, light of a wavelength of 365 nm at 3.08 W in combination with ultrasonic vibration of 28 kHz is sufficient to debond an orthodontic appliance. The combinations of light and vibrational energy may be applied to the orthodontic appliance/adhesive according to any single one of the devices described herein that is capable of irradiating an adhesive and contacting the orthodontic appliance. It will be appreciated that while irradiating and contacting may be simultaneous, embodiments of the invention are not limited to simultaneous application of light and vibration.
• With reference now toFIG. 16A, an exemplarylight device300 is shown and is similar in function to thelight device200 described above. In that regard, thelight device300 physically contacts an orthodontic bracket to permit application of mechanical debonding force to that bracket during or immediately following exposure of an adhesive to light and is another example of direct debonding. In the exemplary embodiment shown inFIG. 16A, thelight device300 has ashell302 that conforms to thebracket12 and to thetooth14. Acavity portion306 of theshell302 defines acavity308 that encloses thebracket12 at least in an occlusal direction and in a labial direction. At least oneprojection310 may close off a portion of thecavity308 to produce an interference fit with thebracket12 in one of the labial direction or the lingual direction. In the exemplary embodiment, theshell302 includes a pair of opposingprojections310. It will be appreciated that the direction of the interference fit depends upon which surface of the tooth thebracket12 is bonded to.
• Theshell302 may be made of an elastic material, such as polyurethane or similar polymer, and so the clinician may elastically deform thecavity portion306 so that theprojections310 fit over thebracket12. By way of example only, theshell302 may be similar in configuration to an aligner. By deforming thecavity portion306, theprojections310 essentially pinch thebracket12 in thecavity308. This is shown by way of example with regard to thearrows322 inFIG. 16A. In this way, thelight device300 may removably receive thebracket12 within thecavity308.
• Embedded within theshell302 are a plurality oflight sources312, which may be similar to thelight sources120 described above or different light sources. Thelight sources312 are arranged in theshell302 to illuminate the adhesive10 according toarrows318. As is shown inFIG. 16A, the light318 penetrates thebracket12. It will be appreciated that thebracket12 in this embodiment may be a ceramic or other material that is transparent or translucent to the light emitted from thelight sources312. The light from thelight sources312 therefore irradiates the adhesive10 through thebracket12. Further in that regard, thelight sources312 may be distributed along the entire perimeter of thecavity portion306 so as to surround the transparent ortranslucent bracket12. Although not shown, thelight sources312 may be an array of light sources that is similar in size or larger than the bond area between the adhesive10 and thebracket12. This may ensure that the adhesive10 is uniformly irradiated.
• The clinician may then leave thelight device300 on the patient's teeth. That is, the clinician need not hold thelight device300 in any particular orientation relative to the adhesive10 during irradiation. Activating thelight sources312 reduces the strength of the adhesive10 as is described above. In one embodiment, the clinician may secure thelight device300 to the patient's teeth, activate thelight sources312 and then proceed to simply wait for a predetermined time. During this period, for example, the clinician may attend to other patients.
• Once the adhesive10 is sufficiently weakened, the clinician may remove theorthodontic bracket12 from thetooth14. In one embodiment, the clinician may apply a shear force in the direction of thearrow314 shown inFIG. 16A on thelight device300 to remove theorthodontic bracket12 from thetooth14. Theorthodontic bracket12 is contained within thecavity308 upon removal of thelight device300 from thetooth14. Although not shown inFIG. 16A, thelight device300 may span multiple orthodontic brackets as is shown inFIG. 3A. In that instance, the clinician may remove thelight device300 following irradiation of the adhesive10 between each of thebrackets12 and the correspondingtooth14 and in doing so remove an entire arch of orthodontic brackets (this may also include removal of the archwire20) or selected ones of the orthodontic brackets with a single motion in the occlusal direction as is indicated byarrow314.
• In one embodiment, theshell302 may further include asecond cavity316 that receives at least an occlusal edge of thetooth14. As shown inFIG. 16A, theshell302 includes aU-shaped portion320 that extends from thecavity portion306. TheU-shaped portion320 defines thesecond cavity316 and may be sized specific to the patient's teeth and so provide a friction-type fit. Advantageously, thesecond cavity316 may hold thelight device300 in position on the patient'stooth14 irrespective of orientation of thelight device300 and after the adhesive10 no longer adheres theorthodontic bracket12 to the patient'stooth14. In other words, thesecond cavity316 may prevent thedevice300 from falling off the patient's teeth in the absence of an adhesive bond between thebracket12 and thetooth14. Thelight device300 contains thebracket12 andarchwire20, if present, to prevent them from dropping into the patient's mouth during debonding.
• With reference now toFIGS. 16B and 16C in which like reference numerals refer to like features with respect toFIG. 16A, light devices similar to thelight device300 inFIG. 16A are shown. Thelight device300 shown inFIG. 16B may be utilized withorthodontic brackets12 that are not transparent or translucent to light emitted from the light sources. To address non-transparency of metallic brackets, thelight sources312 are placed proximate theprojections310 and so that thelight sources312 are positioned to irradiate an edge portion of the adhesive10 when activated. Once activated, the light from thelight sources312 deteriorates the strength of the adhesive10 between the tooth and thebracket12. After sufficient time, thelight device300 together with theorthodontic bracket12 may be removed from the patient'stooth14. By way of example only, removal may include pulling thelight device300 in the direction of thearrow314.
• Thelight device300 shown inFIG. 16C may also address the issue of a non-transparent ornon-translucent bracket12. Irradiation of the adhesive10 may be achieved by positioning thelight sources312 along a portion of thesecond cavity316. As shown, thelight sources312 may line thesecond cavity316 and be oriented toward thetooth14. The patient'stooth14 may be transparent or translucent to selective wavelengths of light, such as wavelengths in the UV spectrum. Thelight sources312 may emit light in those wavelengths. The light then penetrates through the patient's tooth to uniformly irradiate the interface between thetooth14 and the adhesive10. Once the adhesive10 is sufficiently weakened, the clinician may remove theorthodontic bracket12 in accordance with the procedures described in conjunction withFIG. 16A and 16B.
• With reference now toFIGS. 17A-20B, tip structures that physically contact theorthodontic bracket12 or thearchwire20 so that the clinician may apply tensile debonding forces on the adhesive10 during or following irradiation with selected wavelengths are shown. Therefore, instead of application of shear force, which is made possible by other light devices described herein, the light devices inFIGS. 17A-20B make it possible for the clinician to pull on thebracket12 generally perpendicularly to the adhesive10. Advantageously, this may permit more efficient removal of thebracket12 and most, if not all, of the adhesive10 from thetooth14.
• To that end, for example, and with reference toFIGS. 17A and 19, atip structure400 may be removably coupled to a handle, such as thehandle104 shown inFIG. 1. Thetip structure400 may have a configuration similar to thelight device300 shown inFIG. 16A. In that regard, thetip structure400 is in the form of ashell402 that defines acavity404. Theshell402 surrounds thebracket12 on at least a labial side, an occlusal side, a gingival side, and a portion of the lingual side, as shown. Although not shown, it will be appreciated that theshell402 may further surround the mesial and distal sides and so when theorthodontic bracket12 is inserted into thecavity404, thetip structure400 forms an enclosure around thebracket12. A plurality oflight sources406 may be embedded within theshell402 and be positioned to irradiate the adhesive10 from one or more directions. Thelight sources406 may be similar to thelight sources120 described above or different light sources.
• Theshell402 includes a pair of opposingprojections410 which partially close off thecavity404 and thereby form an interference fit with theorthodontic bracket12. Forces applied in the direction of thearrow412 on theorthodontic bracket12 place the adhesive10 in tension. As is shown in the exemplary embodiment,light sources406 may line a portion of thecavity404 and each of theprojections410. Activating thelight sources406 may radiate the entirety of theorthodontic bracket12, and in the case of a transparent or translucentorthodontic bracket12, the light rays414 emitted from thelight sources406 may penetrate theorthodontic bracket12 and so irradiate theadhesive system10.
• Once theadhesive system10 is sufficiently weakened, the clinician may apply tension to theadhesive system10 by pulling thetip structure400 via thehandle104 until the adhesive10 releases theorthodontic bracket12. Thetip structure400 may be configured to span multipleorthodontic brackets12 as is shown inFIG. 19 or even the entire arch of orthodontic brackets. In this way, a singleorthodontic bracket12 may be removed or multiple orthodontic brackets may be removed during a single exposure to light and application of mechanical forces to the weakened bond between each of the selected brackets and the corresponding teeth.
• With reference now toFIG. 17B, atip structure500 is shown coupled to a handle, such as thehandle104 shown inFIG. 1. Thetip structure500 is similar in many respects to thetip structure400 shown inFIG. 17A. However, ashell502 may only surround theorthodontic bracket12 on a labial side and a gingival side. The occlusal side of thebracket12 is not enclosed by theshell502. Consequently, theshell502 includes asingle projection504. Advantageously, the engagement of thetip structure500 may be simplified as compared to thetip structure400 because it is only necessary to engage theprojection504 with theorthodontic bracket12. This may be achieved by a simple hooking motion whereas it may be necessary to deform the opposingprojections410 of thetip structure400 to position thebracket12 in thecavity404. After exposing theadhesive system10 to light from thelight sources406, as is generally indicated byarrows414, the clinician can pull on thebracket12 in the direction ofarrow412. Pulling engages theprojection504 with theorthodontic bracket12 to remove thebracket12 from the patient'stooth14.
• FIG. 17C depicts thetip structure500 in the reverse orientation from the orientation shown inFIG. 17B. This orientation may be advantageous because once removed, theorthodontic bracket12 will stay engaged with thetip structure500 due to gravity. While thetip structure500 is shown engaged with a single bracket, thetip structure500 may span multiple brackets, similar to that shown inFIG. 19 with thetip structure400, and may engage every single one of the brackets along the patient's entire arch. The tip structures described herein may be disposable or autoclavable.
• With reference toFIG. 18, in one embodiment, atip structure600 is configured to remove a singleorthodontic bracket12. Thetip structure600 includes aU-shaped member602 that may be forcibly inserted onto thebracket12 in the direction of thearrow604. TheU-shaped member602 may includeliner606 that frictionally engages theorthodontic bracket12. Thus, insertion of thetip structure600 along the direction ofarrow604 frictionally engages theU-shaped member602 with theorthodontic bracket12.
• Following or during irradiation with light414 from thelight sources406, the clinician may remove the orthodontic bracket in the direction ofarrow412 in a manner similar to that described above with regard to thetip structures400 and500. The clinician may pull on thebracket12 to dislodge it from the tooth.
• Unlike the tip structures described above, thetip structure700 shown inFIGS. 20A and 20B contacts thearchwire20 while thearchwire20 is engaged in eachorthodontic bracket12. Pulling on thearchwire20 during irradiation of the adhesive10 removes all of thebrackets12 connected to thearchwire20. To that end, in one embodiment, thetip structure700 includes a plurality of C-shapedmembers702 that each define acavity704. Thecavity704 receives thearchwire20. A pair ofprojections712 produce an interference fit between the C-shapedmember702 and thearchwire20 so as to permit application of pulling forces on thearchwire20. The plurality of C-shapedmembers702 are coupled together by aconnector706. Thetip structure700 may be removably coupled to a handle, such ashandle104. The number of C-shapedmembers702 may be approximately the same as the number oforthodontic brackets12 on the patient's arch. As shown, the C-shapedmember702 carries a plurality oflight sources708, which may be similar to thelight sources120 described above or different light sources. Thelight sources708 may be oriented in the direction of theorthodontic bracket12 that is situated between adjacent C-shapedmembers702 during use of thetip structure700.
• During use, the clinician attaches each C-shapedmember702 to thearchwire20 by placing thearchwire20 in thecavity704. This positions the C-shapedmember702 adjacent theorthodontic bracket12. Activating thelight sources708 irradiates the adhesive10 of thebrackets12 situated between adjacent C-shapedmembers702. Once the adhesive10 is sufficiently weakened, the clinician may pull the plurality of C-shapedmembers702 in the direction generally indicated by thearrow710 inFIG. 20B. Once the adhesive10 releases each bracket, the clinician may pull an entire arch of brackets off the patient's teeth in a single process.
• Furthermore, according to embodiments of the invention, the photocleavable moiety may enable reversible adhesion of theorthodontic adhesive system10 to the tooth surfaces22. The bonding process and the reversible adhesiveness may even be a type of fast curing (e.g., curing may occur during the few moments when the clinician presses the orthodontic device against the tooth with the catechol derivative-containing compound present on the tooth and the functional monomer present on the restorative part). In one embodiment, theadhesive system10 may be activated and deactivated during bonding and debonding, respectively, with the light device described herein. Curing may include exposing the adhesive to blue light in one or more wavelengths from 450 nm to 495 nm. The adhesion to the tooth may be reversible in the sense that it can be bonded to the tooth and then debonded from the tooth at least twice. This may be useful for when theorthodontic bracket12 orattachment10 is initially improperly positioned. Theorthodontic bracket12 orattachment10 may then be debonded by exposing the adhesive to wavelengths in the ultraviolet light spectrum, for example, from about 380 nm to about 450 nm. Once debonded, theorthodontic bracket12 orattachment10 may be reoriented and re-bonded to thetooth surface22.
• Thus, the adhesive and light devices described herein may facilitate an on-demand bonding and on-demand debonding process that permits easy repositioning of the orthodontic device. This may be referred to as a reusable adhesive system. Advantageously, orthodontic device placement may be perfected without concern that the adhesive polymerizes prior to proper positioning as the adhesive may be selectively bonded and debonded and then rebonded without addition of more adhesive. Clinically, the process of repositioning is tedious, thus embodiments of the adhesive described herein save repositioning time and present a significant shift in the standard of patient care. One or more brackets may be simultaneously bonded and debonded with the light devices disclosed herein.
• In order to facilitate a more complete understanding of the embodiments of the invention, the following non-limiting examples are provided.
EXAMPLE
• A primer solution of 7.5 wt. % 10-Methacryloxydecyl Dihydrogen Phosphate (MDP) that is modified to have a lower acid value (i.e., purified by removing HCl byproduct), 0.005 wt. % Catechol-methacrylate (CMA) (using eugenol as a backbone for the CMA), and 0.0075 wt. % butylated hydroxytoluene (BHT) in a balance of acetone was applied with a brush to a bovine tooth that was prepared by wiping it with a tissue. No other preparation techniques were used to prepare the surface of the tooth.
• A debonding layer is formed from a second solution of 10 wt. % photocleavable bis-methacrylate, 0.01 wt. % N,N-di-methyl-amino-ethyl methacrylate (DMAEMA), 0.01 wt % camphoroquinone (CQ), and 0.001 wt % BHT in a balance of acetone was applied with a brush to the dried primer.
• A Damon® Q metal bracket was bonded to the debonding layer with Grengloo® adhesive and cured according to the manufacturer's directions.
• Debonding of the metal bracket was achieved by exposure to 10 W UV light source at a wavelength of 395 nm in combination with a vibrating scaler operating at 24-32 kHz for about 30 seconds.
• Debonding of a ceramic bracket was achieved at a 28 kHz of vibrational energy with simultaneous exposure to light at 940 nm with a power of 2.75 W in 34 seconds. For comparison, debonding was achieved with UV light at 365 nm and 3.08 W with 28 kHz in about 200 seconds.
• In another example, 40 brackets were bonded to individual bovine teeth as set forth in the previous example. Twenty of the samples were debonded with an Instron® testing machine without irradiating the bond between the bracket in the tooth. The arrangement shown inFIG. 21 is utilized to debond the brackets from the teeth. As shown, tooth was encapsulated in epoxy with the bonded bracket exposed. A wire was looped around the bracket and attached to a grip on a cross head of the Instron® machine. With this arrangement, a shear load was produced on the adhesive. The average debond force measured was about 30 lbs force. Of the 20 samples, it is estimated that 90% of the adhesive remained on each of the teeth after the bracket debonded. Thus, a majority of the adhesive remained on each tooth.
• The remaining 20 samples were irradiated for 1 minute at a distance of about 0.5 cm with an LED that produces a wavelength of 940 nm at 2,750 mW. The estimated bond area between the tooth and the orthodontic bracket was about 0.1 cm². Following that dosage, the arrangement shown inFIG. 21 was utilized to debond the brackets from the teeth. The average debond force measured was about30 lbs force, however, all of the brackets debonded with the adhesive secured to the bracket. That is, there was no adhesive residue visible on any of the teeth for any of the 20 samples.
• While the present invention has been illustrated by a description of various preferred embodiments and while these embodiments have been described in some detail, it is not the intention of the inventors 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 various features of the invention may be used alone or in any combination depending on the needs and preferences of the user.

Claims (22)

What is claimed is:

1. A device for use by a clinician in orthodontics comprising:

a tip structure that is configured to extend from a handle and to be inserted into a patient's mouth; and

at least one light source that is capable of emitting incoherent actinic radiation from the device,

wherein the light source is on the tip structure or within the handle.

2. The device ofclaim 1 further including a sonic or ultrasonic generator coupled to the tip structure and configured to vibrate the tip structure.

3. The device ofclaim 2 further including the handle wherein a housing defines the handle and the sonic or ultrasonic generator is in the housing.

4. The device ofclaim 1 wherein the at least one light source emits light in at least one of an IR spectrum, an NIR spectrum, and an UV spectrum to irradiate a cured adhesive within the patient's mouth.

5. The device ofclaim 1 further including a source of blue light that is capable of emitting light in a blue portion of a visible light spectrum to cure an adhesive within the patient's mouth.

6. The device ofclaim 1 wherein the at least one light source is capable of producing an irradiance of 50 mW per cm²to 250 mW per cm².

7. The device ofclaim 1 wherein the at least one light source is capable of producing an irradiance up to an amount that does not heat a cured adhesive within a patient's mouth.

8. The device ofclaim 1 wherein the handle includes a socket and the tip structure is one of a set of a plurality of different tip structures, and each of the tip structures in the set is capable of being removably coupled to the handle in the socket.

9. The device ofclaim 1 wherein the tip structure includes a bite plate and a sidewall that is configured to face a surface of the patient's teeth and the at least one light source is positioned in the sidewall, the tip structure being configured to irradiate an entire arch of the patient's mouth.

10. The device ofclaim 1 wherein the tip structure includes a shell configured to physically contact the orthodontic appliance.

11. The device ofclaim 10 wherein the shell includes a cavity defined in part by opposing projections.

12. The device ofclaim 10 wherein the shell includes at least one projection capable of contacting and applying a tensile force on the orthodontic appliance.

13. The device ofclaim 1 wherein the tip structure includes a tool for contacting the orthodontic appliance and the at least one light source is adjacent the tool.

14. A light device comprising:

a shell that is configured to engage an orthodontic bracket while the orthodontic bracket is attached to a tooth; and

at least one light source embedded in the shell and that is capable of emitting incoherent actinic radiation.

15. The device ofclaim 14 wherein the shell defines a cavity configured to receive the orthodontic bracket and the at least one light source is configured to irradiate the cavity.

16. The device ofclaim 15 wherein the cavity includes opposing projections that are configured to create an interference fit with the orthodontic bracket when the bracket is in the cavity.

17. The device ofclaim 14 wherein the shell further includes a U-shaped portion that is configured to fit over an occlusal edge of the tooth.

18. The device ofclaim 14 wherein the at least one light source emits light in at least one of an IR spectrum, an NIR spectrum, and an UV spectrum to irradiate a cured adhesive within the patient's mouth.

19. The device ofclaim 14 wherein the at least one light source includes a first light source for the IR or NIR spectrums and a second light source for the UV spectrum.

20. The device ofclaim 14 wherein the at least one light source is capable of producing an irradiance of 50 mW per cm²to 250 mW per cm².

21. The device ofclaim 14 wherein the at least one light source is capable of producing an irradiance that does not heat a cured adhesive within the patient's mouth.

22. A method of debonding an orthodontic appliance from a tooth comprising:

exposing an adhesive secured to the tooth to incoherent actinic radiation that reduces a bond strength of at least a portion of the adhesive; and

separating the orthodontic appliance from the tooth at the portion of the adhesive having reduced bond strength.

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