Hot melt dental materials and devices and methods for using the same

Example embodiments of the present invention include hot melt dental adhesive materials that can create a reversible bond. In addition, example embodiments of the present invention include hot melt dental impression materials that can be used to accurately and efficiently obtain a dental impression. Moreover, example embodiments of the invention include devices and methods for use with the hot melt dental adhesive materials and the hot melt dental impression materials disclosed herein. The hot melt dental adhesive materials and the hot melt dental impression materials can provide dental professionals with dental materials that are more effective, efficient, and easier to use when compared to conventional dental adhesive materials and conventional dental impression materials.

TECHNICAL FIELD OF THE INVENTION

The present disclosure relates to the field of dental adhesives and impression materials, including related devices and methods.

BACKGROUND OF THE INVENTION

Dental professionals commonly utilize various types of dental adhesive materials and dental impression materials in their daily dental practice. As an example, dental adhesive materials may be used to bond composites to teeth or to bond prosthetic restorations, such as crowns, into place. In addition, dental professionals may also use dental impression materials to obtain a dental impression of teeth in the process of fabricating a prosthetic restoration. Conventional dental adhesive materials and dental impression materials have several disadvantages.

On example disadvantage of conventional dental adhesive materials is the fact that conventional dental adhesive materials are generally designed to be a permanent adhesive when cured (e.g., once the permanent adhesive is cured, it is no longer possible to reverse the curing process and undo the bond created by the permanent adhesive). Often times, however, the dental professional may need to later break the bond formed by the dental adhesive material to complete a dental procedure after the dental adhesive material has cured.

For example, a conventional crown may be bonded to a tooth using a permanent adhesive. At a later time, however, the patient may develop a problem with the crowned tooth that requires the dental professional to remove the crown. Due to the permanent adhesive, the dental professional may have to drill, cut and break the crown to remove the crown from the bonded surfaces. This process of course destroys the crown, is uncomfortable for the patient, and increases cost.

Likewise, dental professionals bond orthodontic brackets to teeth using conventional permanent adhesives. Similar to the example of the crown, the dental professional often times must pry the orthodontic brackets off of the patient's teeth and aggressively remove any residual cured adhesive from the tooth with a diamond bur when the orthodontic brackets are no longer required. Thus, the process of removing orthodontic brackets becomes a costly time consuming process that may potentially scar or mark the patient's teeth.

As with conventional adhesive materials, conventional dental impression materials also have disadvantages. The conventional method of taking a dental impression involves the dental professional mixing a first and second component to form the dental impression material that chemically cures over a certain period of time. For example, when the first and second components are initially mixed, the dental impression material may be a paste-like-substance. The paste-like-substance is usually placed in a dental tray device and the patient is asked to bite down on the paste-like-substance allowing the patient's teeth to make an impression in the dental impression material. After a period of time, the dental impression material chemically cures and the paste-like-substance forms a hardened material that holds the shape of the dental impression.

As illustrated above, conventional dental impression materials require a time sensitive mixing process that relies on the dental professional to act quickly to set the dental impression material in a patient's mouth before the dental impression material starts to cure. Additionally, once the dental professional sets the dental impression material in a patient's mouth, the dental impression material may take several minutes to fully cure to the point that allows the dental professional to remove the material and maintain an accurate dental impression. Due to the curing time, the patient may be uncomfortable during the curing of the dental impression material (e.g., many patients experience a gag reflex while waiting for the dental impression material to cure). Moreover, any mouth movement during the curing of the dental impression material may result in an inaccurate dental impression, causing the dental professional to have to repeat the entire process.

Accordingly, there are a number of disadvantages in the conventional art of dental adhesive materials and dental impression materials.

SUMMARY OF THE INVENTION

Example embodiments of the present invention include hot melt dental adhesive materials that can create a reversible bond. In addition, example embodiments of the present invention include hot melt dental impression materials that can be used to accurately and efficiently obtain a dental impression. Moreover, example embodiments of the invention include devices and methods for use with the hot melt dental adhesive materials and the hot melt dental impression materials disclosed herein. The hot melt dental adhesive materials and the hot melt dental impression materials can provide dental professionals with dental materials that are more effective, efficient, and easier to use when compared to conventional dental adhesive materials and conventional dental impression materials.

DETAILED DESCRIPTION OF THE INVENTION

Example embodiments of the present invention include hot melt dental adhesive materials that can create a reversible bond. In addition, example embodiments of the present invention include hot melt dental impression materials that can be used to accurately and efficiently obtain a dental impression. Moreover, example embodiments of the invention include devices and methods for use with the hot melt dental adhesive materials and the hot melt dental impression materials disclosed herein. The hot melt dental adhesive materials and the hot melt dental impression materials can provide dental professionals with dental materials that are more effective, efficient, and easier to use when compared to conventional dental adhesive materials and conventional dental impression materials.

As briefly discussed, one example embodiment of the present invention includes a thermoplastic polymer that can be used in a dental impression system to efficiently and accurately obtain a dental impression for any portion of a patient's dental arch. For example,FIG. 1illustrates on example embodiment of a dental impression system100. The dental impression system100can include a hot melt dental impression material102that is a single component (i.e., there is no need to mixing two or more components prior to use as with conventional dental impression materials) and made out of a thermoplastic polymer. Example thermoplastic polymers that can be used to create the hot melt dental impression material102include, but are not limited to, polycaprolactone, high molecular weight polycaprolactone, and materials that exhibit similar properties.

The hot melt dental impression material102can have various material properties. For example, and as illustrated inFIG. 1, the hot melt dental material102can have a first solid state102awhen the hot melt dental material102is about 45 degrees C. or cooler, and a second liquid state102bwhen the hot melt dental material102is about 45 degrees C. or warmer. In one example embodiment, the hot melt dental impression material can have a melting point in the range of about 40 degrees C. to about 60 degrees C.

Notwithstanding the particular melting point, when in the first solid state102b, the hot melt dental impression material102maintains elastomeric flexibility. For example, when in the first solid state102a, the hot melt dental impression material102can be stretched, flexed, and distorted away from an original shape when a force is applied to the dental impression material102. Upon removal of the force, however, the dental impression material102elastically returns to the original shape.

On the other hand, when the hot melt dental impression material102is in the second liquid state102b, the hot melt dental impression material has a viscosity that allows the hot melt dental impression material102to flow evenly over teeth. In particular, the viscosity of the hot melt dental impression material102allows the material to penetrate the nooks and crevices within a dental arch104to create an accurate dental impression, but at the same time is viscous enough to not run off the dental arch104, as illustrated inFIG. 1.

Various material properties of the hot melt dental impression material102such as viscosity, flow rate, melting point, Young's modulus, flexibility, plasticity, and many other characteristics can be modified by the addition or subtraction of specific modifiers such that specific desired properties of the final compounded thermoplastic are achieved. For example, the thermoplastics of the present invention can be designed for a specific dental application such that the most desired properties are maximized. With the above identified material properties, the hot melt dental impression material102can accurately and efficiently be used to obtain a dental impression106.

In addition to the hot melt dental impression material102, the dental impression system100can further include a delivery device108. As illustrated inFIG. 1, the hot melt dental impression material102can have a specific geometric form to cooperate with the corresponding delivery device108. For example,FIG. 1illustrates that the dental impression material102can have substantially cylindrical stick-like form that can be loaded into the corresponding delivery device108. The dental impression material102can have almost any geometric form depending on the configuration of the delivery device108.

The delivery device108can vary greatly from one embodiment to the next, but in general the delivery device108can be configured to change the hot melt dental impression material102from the first solid state102ato the second liquid state102b. For example,FIG. 1illustrates one example embodiment of the delivery device108can have the form of a heat gun. In particular, the delivery device108can include a handle110, a guide112, and a heat source114. The delivery device108can further include a trigger116and an aperture118. As illustrated inFIG. 1, a dental professional can dispense the hot melt dental impression material102on a dental arch104by positioning the aperture118in proximity of the dental arch104and applying a force to the trigger116.

In particular, when the dental professional applies force to the trigger116, the hot melt dental impression material102in the first solid state102ais forced by the guide into the heat source114. The heat source114can be electrically powered by plugging the delivery device108into an electrical socket, or the heat source114can be battery powered. The heat source114can heat the hot melt dental impression material102to change from the first solid state102ato the second liquid state102b. The hot melt dental impression material102is subsequently forced out of the aperture118in the second liquid state102band dispensed on the dental arch106. The size of the aperture118can vary from one embodiment to the next to facilitate various flow rates of the hot melt dental impression material102.

In one example embodiment, the heat source114can have a temperature control that can adjust the temperature at which the heat source114heats the hot melt dental impression material102. The adjustable temperature control allows the same delivery device108to be used with potentially different hot melt dental impression materials102that have different melting points. Moreover, the adjustable temperature control allows the dental professional to help control the viscosity of the hot melt dental impression material102as the heat source114changes the hot melt dental impression material from the first solid state102ato the second liquid state102b. For example, the higher the temperature setting on the temperature control, the less viscous the second liquid state102b. In addition, controlling the temperature allows the hot melt dental impression material102to melt at a safe temperature for use on the patient.

Once the hot melt dental impression material102is dispensed on the dental arch104, the hot melt dental impression material102is allowed to cool to below the melting point. The cooling process changes the hot melt dental impression material102from the second liquid state102bback to the first solid state102a. In one embodiment, the dental professional can quickly cool the material by spraying the material with cooled water from a conventional three-way dental syringe. Other cooling methods may be used, such as passing cool air around and over the hot melt dental impression material102. When a dental impression106is cool and solidified, the dental professional can remove the dental impression106from the dental arch104by simply peeling the dental impression106away from the dental arch104.

Just as thermoplastics can be used as a dental impression material, thermoplastics can also be used as hot melt dental adhesive material. Hot melt adhesive materials can include a thermoplastic component. The thermoplastic component can include, but is not limited to, ethylene-vinyl acetate polymers and copolymers, polycaprolactone polymers and co-polymers, polyolefin polymers, amorphous polyolefin polymers and copolymers, such as low density polyethylene or polypropylene, atactic polypropylene, oxidized polyethylene, and polybutene-1; ethylene acrylate polymers and copolymers, such as ethylene-vinylacetate-maleic anhydride, ethyleneacrylate-maleic anhydride terpolymers like ethylene n-butyl acrylate, ethylene acrylic acid, ethylene-ethyl acetate; polyamide polymers and copolymers, polyester polymers and copolymers, polyurethane polymers and copolymers, Styrene polymers and copolymers, polycarbonate polymers and copolymers, silicone rubber polymers and copolymers, polysaccharide polymers and copolymers, fluoropolymers, polypyrrole polymers, polycarbonate polymers and copolymers, waxy polymers and copolymers, waxes, copolyvidones (copovidones), polyacrylic acid polymers and copolymers, polymaleic acid polymers and copolymers, polyimides, polyvinyl chloride polymers and copolymers, poly(ethylene-comethacrylic acid) copolymers, and any other useful plastics, polymers and copolymers, and/or any combination thereof.

Notwithstanding the thermoplastic component, the hot melt dental adhesive material can include various additive components to achieve various different material properties. Additive components can include, without limitation, radiant energy absorbent dyes, radiant energy absorbent pigments, fillers, stabilizers, tackifying resins, plasticizers, medicaments, and/or other agents that are capable of improving the application and delivery of the thermoplastic component. One or more of the above additive components can be incorporated with the thermoplastic component of the hot melt dental adhesive material in almost any amount to achieve the desired material properties.

In addition to radiant absorbent dyes and pigments, various fillers can be added to the thermoplastic component to modify the physical properties of the hot melt dental adhesive material (e.g., increase stiffness and viscosity when molten). Examples of fillers include, but are not limited to, fumed, ground, and precipitated silicas, clays, barium sulfate, strontium sulfate, calcium carbonate and any other useful filler.

Likewise, stabilizers can be incorporated into the hot melt dental adhesive material to protect the plastic from harmful environmental effects during use. Examples of stabilizers include, but are not limited to, UV stabilizers, biocides, anti-static agents and any other useful stabilizers.

In addition, tackifying agents can be incorporated into the hot melt dental adhesive material to increase the adhesiveness of the plastic such that it adheres better to a given substrate. Tackifying agents include, but are not limited to, all natural rosins and their derivatives, terpenes and modified terpenes, hydrogenated hydrocarbon resins, terpene-phenol resins, aliphatic resins, cycloaliphatic resins, aromatic resins and any other useful tackifying agent.

Moreover, the thermoplastic component of the hot melt dental adhesive material can be modified for increased adhesion beyond the addition of tackifying agents. Various moieties can be grafted onto the thermoplastic component polymers to increase adhesion to a specific substrate. For example, polycaprolactone at a molecular weight average of 65,000 has a melting point of 60 degrees C., which is an ideal temperature for use on live teeth. Polycaprolactone can be further modified to incorporate different substituents, for example, a carboxylic acid group or a phosphate group for increased adhesion to enamel. The same polycaprolactone thermoplastic component could be synthesized to incorporate a silane substituent for increased adhesion to porcelain. Various combinations of substituent groups could be added to the polycaprolactone to give it a more universal adherence to multiple substrates. The grafting of substrate interaction substituents into the desired thermoplastic component polymer for increased adhesion characteristics is within the scope of this patent.

In addition to engineering the hot melt dental adhesive material to be more adhesive, plasticizers can be incorporated into the hot melt dental adhesive material to soften the thermoplastic component and make the thermoplastic component more pliable and flexible. Examples of plasticizers include, but are not limited to, mineral oil, triethyl citrate, acetyltriethyl citrate, lauric acid, modified vegetable oils, diacetylated mono glycerides, castor oil, triacetin, glycerin, liquid polyethylene glycols, liquid poly propylene glycols, propylene glycol, dimethyl phthalate, diethyl phthalate, dipropyl phthlate, dibutyl phthalate, dioctyl phthalate, polysorbates, 1,4-cyclohexane dimethanol dibenzoate, glyceryl tribenzoate, pentaerythritrol tetrabenzoate and/or any other useful plasticizer.

Various physical characteristics such as viscosity, flow rate, melting point, compressive strength, tensile strength, Young's modulus, flexibility, plasticity, and many other characteristics can be modified by the addition or subtraction of specific modifiers such that specific desired properties of the final compounded plastic are achieved. The plastics of the present invention can be designed for a specific dental application such that the most desired properties are maximized.

Another embodiment of the present invention incorporates beneficial active medicament ingredients into the hot melt dental adhesive material. The active medicament ingredients can be added in proportions that allow treatment of conditions found in the oral environment such as caries, infections, fungal growths and any other detrimental oral condition. Active ingredients can also be added to treat various bodily conditions. For example, a pharmaceutical ingredient can be added to provide a constant dosage of a medicine orally over an extended period of time. Any pharmaceutical or medicine can be incorporated into the hot melt dental adhesive.

One or more active medicament ingredients can be blended into the hot melt dental adhesive materials in sufficient quantities to form an active medicament ingredient filled sponge-like matrix that provides a steady release of the active medicament ingredients upon contact with saliva. Moreover, soluble plasticizers can be added to ensure adequate release of the active medicament ingredients during the treatment regime.

Various active medicament ingredients can be incorporated into the hot melt dental adhesive material such as fluoride, pH adjusting compounds like sodium carbonate, sodium hydroxide and other basic substances, re-mineralization compounds such as calcium phosphate, calcium citrate, calcium lactate and other like compounds, antimicrobial agents such as chlorhexidine gluconate, sodium chlorite, triciosan, and other like compounds, any salt found naturally in saliva, and any beneficial substance used to treat a disease or condition found in the oral environment.

Notwithstanding the various compositions and components of the hot melt dental adhesive material, the hot melt dental adhesive material can be utilized in various dental applications. For example,FIGS. 2A and 2Billustrate one example of using the hot melt dental adhesive material for dental prosthetics (e.g., crowns, bridges, onlays, and inlays). As shown inFIG. 2A, and similar to the hot melt dental impression material102, the hot melt dental adhesive material202has a first solid state202aand a second liquid state202b. A dental professional can use a delivery device208to change the hot melt dental adhesive material202from the first solid state202ato the second liquid state202b. The delivery device208can have the same or similar features as the delivery device108described with reference toFIG. 1.

As illustrated inFIG. 2A, the dental professional, can use the delivery device208to express the hot melt dental adhesive material202into a restoration prosthetic204. In particular, the dental professional can squeeze the trigger to force the hot melt dental adhesive material202in the first solid state202ainto the heating element where the hot melt dental adhesive material202is melted and expressed from the delivery device in the second liquid state202b. In one example embodiment, the restoration prosthetic can include a well206into which the dental professional expresses the hot melt dental adhesive material202in the second liquid state202b. In alternative embodiments, the dental professional can express the hot melt dental adhesive material202on any surface of the restoration prosthetic204to be bonded. Alternatively, the dental professional can apply the hot melt dental adhesive material202directly to the mating surface210first, and then install the restoration prosthetic204.

Once the hot melt dental adhesive material202is expressed on the restoration prosthetic204, the dental professional can position the restoration prosthetic on a mating surface210to which the restoration prosthetic204is to be bonded. For example,FIG. 2Billustrates that the dental professional can insert the mating surface210into the well206of the restoration prosthetic204until the hot melt dental adhesive material202in the second liquid state202binterfaces between the restoration prosthetic204and the mating surface210.

When the dental professional has finished positioning the restoration prosthetic204on the mating surface210, the hot melt dental adhesive material202is allowed to cool and this change from the second liquid state202bback to the first solid state202a. The first solid state202aforms a strong mechanical bond between the restoration prosthetic204and the mating surface210. The dental professional can speed up the cooling time by rinsing the restoration prosthetic204with cool water, or blowing cool air around the restoration prosthetic.

In at least example embodiment, the bonding surfaces on the dental prosthetic204and the mating surface210can be etched or otherwise prepared to increase the strength of the bond between the hot melt dental adhesive material202and the respective surfaces. In particular, any preparation to the bonding surfaces that causes the bonding surfaces to have a texture to which the hot melt dental adhesive material202can penetrate while in the second liquid state202bwill be beneficial in increasing the strength of the mechanical bond by allowing the hot melt dental adhesive material202to physically hook or mechanically attach to the respective bonding surfaces upon changing back to the first solid state202a.

Notwithstanding the method illustrated inFIGS. 2A and 2B, the hot melt dental adhesive material202can be applied using various other forms and methods. For example, in one embodiment the hot melt dental adhesive material202includes a solvent in order to put the hot melt dental adhesive material202into solution. When in solution, there is no need for a dental professional to heat the hot melt dental adhesive material202to apply; rather, the dental professional simply applies the solvent dissolved hot melt dental adhesive material202directly onto the bonding surfaces. Once the hot melt dental adhesive material202in solution is applied, the solvent evaporates and the hot melt dental adhesive material202becomes a rigid material that is substantially the same as the hot melt dental adhesive material202in the first solid state202aas discussed above, and thereby forming a strong mechanical bond.

In order to use the solvent solution method, the hot melt dental adhesive material202can include a thermoplastic component that is soluble in solvents other than water. For example, thermoplastic components that are soluble in solvents that are minimally non-hazardous are preferred. Non-hazardous solvents include, but are not limited to, solvents such as ethanol, acetone, and/or alkane solvents such as hexane, heptane, dimethyl pentane and others similar compositions.

Polyamides are an example of a thermoplastic component that is soluble in ethanol and are therefore especially beneficial. The hot melt dental adhesive material202manufacturer can mix or blend the thermoplastic component with the appropriate solvent until it dissolves, becomes a semi-soluble paste, or a gel type consistency. The thermoplastics of choice are those with substituent groups that maximize adhesion to surfaces such as carboxylic acid groups, phosphate groups, amine groups, amide groups and any polymeric moiety that increases adhesion to substrates such as teeth, porcelain, and metals.

Once in solution, the dental professional can directly apply the hot melt dental adhesive material202to restoration prosthetics such as crowns, bridges, onlays, and inlays. For example, the hot melt dental adhesive material202in solution can be a gel or paste that the dental professional can simply apply by brush onto the bonding surfaces and set into place and held until the solvent or solvents evaporate forming a solid bond. In one embodiment, the dental profession can speed up the solvent evaporation time by heating the site with a laser, heat wand, heated bag, heated bite block, heated cotton roll while biting down, or any device that adds heat to the bonding site.

Notwithstanding the original form of the hot melt dental adhesive material202, or the method by which it is applied, the bond formed between the restoration prosthetic204and the mating surface210is reversible. In particular, a dental professional can easily and efficiently reverse the bond of the hot melt dental adhesive material202by again changing the hot melt dental adhesive material202from the first solid state202ato the second liquid state202b. Therefore, removal of the restoration prosthetic204following application is accomplished through re-heating the hot melt dental adhesive material202into the second liquid state202b.

FIGS. 3A and 3Billustrate various embodiments of heating devices that a dental professional can use to re-heat the hot melt dental adhesive material202after a bond is formed. For example,FIG. 3Aillustrates a heating device300that can be configured to direct heat towards the restoration prosthetic304. The heating device300can include a grip handle302so that the dental professional can easily manipulate the heating device300within a patient's mouth. Although the hand grip302illustrated inFIG. 3Ahas a substantially cylindrical configuration, the hand grip302can have almost any geometric configuration that allows a dental professional to direct towards a specified area within a patient's mouth.

In addition to the grip handle302, the heating device300can be connected to a power source that powers a heating element306. For example, the heating device300illustrated inFIG. 3Aincludes a power cord304that connect to an external power source. In an alternative embodiment, the heating device300can include an internal power source such as a battery.

As mentioned, the power source provides power to the heating element306. As illustrated inFIG. 3A, the heating element306can be a convection heating element that generates an air current of heated air308that is directed towards the restoration prosthetic304. For example, the dental professional can continue to direct the air current of heated air308towards the restoration prosthetic304heating the restoration prosthetic304material, which thereby heats the hot melt dental adhesive material202within the restoration prosthetic304. Once the temperature of the hot melt dental adhesive material202raises above the melting point of the hot melt dental adhesive material202, the dental professional can begin to simply remove the restoration prosthetic304without any damage to the underlying mating surface or the restoration prosthetic304.

In an alternative embodiment, the heating element306can be a conductive heating element. For example, the heating element can physically heat up and the dental professional can place the heating element in contact with the dental prosthetic. Thus, through conduction, heat is transferred from the heating element306to the restoration prosthetic304and eventually to the hot melt dental adhesive material202. Again, once the temperature of the hot melt dental adhesive material202raises above the melting point of the hot melt dental adhesive material202, the dental professional can easily remove the restoration prosthetic304.

In addition to convection and conduction heating, the heating can come from a radiant energy source. For example,FIG. 3Billustrates a laser heating device310that uses a laser as a radiant energy source. In particular, the laser heating device310includes a handle portion312that a dental professional can use to manipulate the laser heating device310within the patient's mouth. The laser heating device310can further include an optical fiber connection that is connected to a laser source and directs the laser through the handle portion312.

Furthermore, the laser heating device can include an exit aperture316that directs and focuses radiant energy318. For example, as illustrated inFIG. 3B, the exit aperture316focuses the radiant energy318on the restoration prosthetic304. In one example, the exit aperture316is adjustable to allow the dental professional to adjust the focus and intensity of the radiant energy318emitted from the laser heating device310. The dental professional can emit the radiant energy318towards the restoration prosthetic304for a period long enough to heat the hot melt dental adhesive material202within the restoration prosthetic to a temperature above the melting point of the hot melt dental adhesive material202. Once the temperature of the hot melt dental adhesive material202is above the melting point, the dental professional can easily remove the restoration prosthetic304.

Many restoration prosthetics304on the market are somewhat translucent such that some radiant energy318can infiltrate through them and reach the hot melt dental adhesive material202within the restoration prosthetic304. For example, all ceramic restoration prosthetics304are a good example of a slightly translucent restoration material. In particular, radiant energy318from a laser or similar device can penetrate through the porcelain to the hot melt dental adhesive material202where the radiant energy318is absorbed by the radiant energy absorbent dye or pigment within the hot melt dental adhesive material202. Thus, the hot melt dental adhesive material202eventually is heated above the hot melt dental adhesive material202melting point and is easily removed.

On the other hand, there are some restoration materials that utilize radiant energy opaque substances like metals. For example, a metal fused to porcelain crown (PFM). A PFM comprises a metal casing surrounded by a porcelain veneer and is substantially radiant energy opaque. Although the radiant energy318will not pass through the metal casing, the metal casing can absorb the radiant energy318and become heated wherein it becomes hot enough to melt the hot melt dental adhesive material202beneath it for easy removal.

In addition to bonding restoration prosthetics, the hot melt dental adhesive material202, various additional example embodiments can be formulated to be a fill cement that is capable of bonding to a substrate such as a tooth or porcelain and at the same time fill in an area where bulk fill material is needed. For example, to fill in an area lost when a cavity is removed. Thus, the hot melt dental adhesive material202can be both a prosthetic and a cement all-in-one.

For bulk fill applications, the hot melt dental adhesive material202can incorporate a filler material such as a ground radiopaque glass that releases fluoride and increases the hardness and friction wear-ability of the all-in-one restoration material. In one embodiment, the hot melt dental adhesive material202can be placed into an etched tooth cavity by expressing molten hot melt dental adhesive material202from the delivery device208. After express, the dental professional can easily manipulate the hot melt dental adhesive material202while in the second liquid state202b, and can be re-melted and modified if any alterations are desired.

In addition to an all-in-one filler material, the hot melt dental adhesive material202can also provide a compound for pulp capping and root end filling procedures. For example, the hot melt dental adhesive material202can incorporate calcium hydroxide and a radiation opaque compound. The calcium hydroxide can be releasable from the hot melt dental adhesive material202in a moist/wet environment and act as a root canal biocide/antimicrobial for root ends or to stimulate bridge formation in a pulp capping procedure.

The hot melt dental adhesive material202can be positioned within the root canal with a delivery device208that has a small aperture tip to express the hot melt dental adhesive material202into the root canal where it seals the root end upon cooling. The hot melt dental adhesive material202offer significant benefits over conventional root sealers because the hot melt dental adhesive material202becomes hard as quickly as it cools, whereas current root end cements harden slowly and make it more difficult to finish the restoration in a single procedure. In any procedure, when the hot melt dental adhesive material202is cooled and becomes hard, the dental professional can immediately move to the next restoration step without further waiting.

The hot melt dental adhesive material not only can be used for general dental purposes and restoration prosthetics, but can also be used in the orthodontic field. For example, the hot melt dental adhesive material is an ideal material to use to bond an orthodontic bracket to a tooth, which allows a dental professional to easily remove the orthodontic bracket due to the reversible nature of the hot melt dental adhesive material. The hot melt dental adhesive material can be applied to the orthodontic bracket and attached to the tooth in the same or similar methods discussed with respect toFIGS. 2A-2Band restoration prosthetics. Moreover, the bond formed by the hot melt dental adhesive material can be reversed using the same or similar methods as discussed with respect toFIGS. 3A-3B.

FIG. 4Aillustrates another embodiment of the present invention that incorporates a hot melt dental adhesive layer406onto an orthodontic bracket400. For example,FIG. 4Aillustrates the orthodontic bracket400having a base portion420and extended portion404. In one example, the orthodontic bracket400can be made of a translucent material. For example, the orthodontic bracket400can be a material that is at least semi-translucent to radiant energy in the range of about 810 nm wavelength. In this way, a laser or similar device can transmit radiant energy though the orthodontic bracket400.

In alternative embodiments, the orthodontic bracket400material can be made from any other types of traditional materials as well, including radiant energy opaque materials. If the orthodontic bracket400is made from a radiant energy opaque material, radiant energy from a laser or similar device can be used to directly heat the orthodontic bracket400material, which by conduction of heat through the orthodontic bracket, will transmit energy through the orthodontic bracket400.

Notwithstanding the material of the orthodontic bracket400, a hot melt dental adhesive layer406can be positioned on the base portion402of the orthodontic bracket400. For example,FIG. 4Aillustrates that hot melt dental adhesive layer406can be positioned prior to the dental profession receiving the orthodontic bracket, thus providing a ready-made orthodontic bracket. The thickness dimensions of the hot melt dental adhesive layer406can vary from one embodiment to the next depending on the size of the orthodontic bracket400, the tooth location of the orthodontic bracket, and the formulation of the hot melt dental adhesive layer406.

In order to provide the hot melt dental adhesive layer406, the manufacturer can use an injection mold process. For example, the orthodontic bracket400can be placed in a mold that includes a small gap proximate to the base portion402of the orthodontic bracket400. Molten hot melt dental adhesive material can then be injected into the small gap and allowed to cool. Upon cooling, the hot melt dental adhesive material hardens and bonds to the base portion402of the orthodontic bracket400and is ready for use.

In order to increase the bond strength between the base portion402and the hot melt dental adhesive layer406, the base portion402can include a textured surface. In particular, a texture surface can be provided on the base portion402that allows the molten hot melt dental adhesive material to penetrate pockets or other similar features. Upon cooling and hardening the hot melt dental adhesive layer406will then physically interface with the textured surface creating a strong mechanical bond.

In addition to the hot melt dental adhesive layer406, the orthodontic bracket400can further include features and devices that can be used to create a weak temporary adhesion between the extended portion404of the orthodontic bracket400and a dental handpiece to aid in positioning the orthodontic bracket400on a patient's tooth. For example,FIG. 4Aillustrates that a double-sided weak adhesive layer408can be applied to the extended portion404. The weak adhesion layer408can be made from any material that creates a weak temporary adhesive bond that is strong enough to support the weight of the orthodontic bracket400.

In one embodiment, the weak adhesion layer408can be made from silicon oil polymer. Surprisingly, it has been found that silicon oil polymers are translucent to radiant energy in the wavelength range of about 810 nm. Thus, a weak adhesion layer408made from a silicon oil polymer will allow radiant energy from a laser or similar device to pass through the weak adhesion layer408, as will be discussed further below. Other similar materials may be used to make the weak adhesion layer408. For example, instead of pre-forming the weak adhesion layer408on the extended portion404, the dental professional may simply dip the tip of a handpiece (seeFIG. 4B) in a silicon oil polymer liquid or paste, which in turn provides an instant weak adhesion layer on the tip portion of the handpiece to allow the orthodontic bracket to temporarily adhere to the handpiece.

Due to the fact that the weak adhesion layer408is double-sided (e.g., both sides of the layer have adhesive properties), a release liner410may be placed on the weak adhesion layer408to protection the outer adhesive surface of the weak adhesion layer408. Just prior to using the orthodontic bracket400, the dental professional can remove the release liner410and expose the weak adhesion layer408, and thus allow the dental professional to temporarily attach the orthodontic bracket400to a handpiece for installation on a patient's tooth.

For example,FIG. 4Billustrates one example of a handpiece412that can be used to install the orthodontic bracket400. The handpiece can be any instrument that allows the dental professional to accurately place the orthodontic bracket400. As illustrated inFIG. 4B through 4D, the handpiece412can include a laser that provides radiant energy. In other example embodiments, the handpiece and the heat source providing device may be separate devices (e.g., see the devices described with reference toFIGS. 3A and 3B).

As illustrated inFIG. 4B, the handpiece412can include a handle portion414that allows the dental professional to manipulate the handpiece. The handle portion414can have any configuration, for example,FIG. 4Billustrates that the handle portion414has a substantially cylindrical geometric configuration. The handle portion414can further include controls that control the laser or similar device, or alternatively, the controls can be located on a control unit or foot pedal.

In addition to the variations in the handle portion414, the handpiece412can also include a tip portion418. The tip portion418can be specifically configured to transmit laser energy from the handpiece into the orthodontic bracket400. Moreover, the tip portion418can also be configured to temporarily attach to the orthodontic bracket400such that the dental professional can use the handpiece412to secure the orthodontic bracket400to the tip portion418, and then use the handpiece412to position the orthodontic bracket400on the patient's tooth.

The handpiece412illustrated inFIG. 4Bhas a tip portion418configured to interface with the orthodontic bracket400illustrated inFIG. 4A. In particular, the tip portion418includes a mounting surface420configured in size and geometric configuration to interface with the weak adhesive layer408on the orthodontic bracket400. In particular, mounting surface420is a substantially flat smooth surface that will interface and engage the weak adhesive layer408.

For example,FIG. 4Cillustrates one method of preparing to attach the orthodontic bracket400to a tooth. As shown inFIG. 4C, the dental professional has removed the release liner410to expose the surface of the weak adhesion layer408. The dental professional can then attach and temporarily secure the orthodontic bracket400to the tip portion418such that the hot melt dental adhesive layer406is located in a position ready to make contact with a patient's tooth.

FIG. 4Dillustrates the orthodontic bracket400temporarily attached to the tip portion418and being positioned to install the orthodontic bracket400to the tooth426. In one example embodiment, when the orthodontic bracket400is appropriately placed against the tooth26with firm pressure, radiant energy424(e.g., a laser) is directed toward the orthodontic bracket400. As explained above, and as illustrated inFIG. 4D, the radiant energy424can pass through the weak adhesion layer408and the orthodontic bracket400material to reach the hot melt dental adhesive layer406.

Upon the radiant energy424reaching the hot melt dental adhesive layer406, the radiant absorbent dyes or pigments found in the hot melt dental adhesive layer406absorbs the radiation, causing the hot melt dental adhesive layer406to heat up to a temperature greater than the melting point of the hot melt dental adhesive layer406. Once the hot melt dental adhesive layer406becomes molten, the supply of radiant energy424is stopped and the hot melt dental adhesive layer406cools forming a bond between the orthodontic bracket400and the tooth426.

The handpiece412can be connected to a controller that is programmed to compliment the hot melt dental adhesive layer406. For example, the controller can control the duration of the radiant energy supply and also time the cool down time such that the dental professional only needs to place the orthodontic bracket400in the correct position and press a cycle start button and the controller will ensure a proper bond is formed. In one example, the controller can be equipped with a feedback interface to give the dental professional visual or audible feedback throughout a bonding cycle.

An example bond cycle controlled by the controller can proceed as follows. The dental professional can initialize the start of the bond cycle by pressing a button or depressing a pedal. The controller can then start supplying radiant energy for a particular duration of time needed to melt the hot melt dental adhesive layer406. The controller may then cut the supply of the radiant energy and begin a cooling countdown function that is a duration that the hot melt dental adhesive layer406solidifies. Once the countdown function is complete, the controller can provide audible feedback (e.g., a beep) indicating to the dental professional that the bond cycle is complete. The controller may further include an input interface that allows the dental professional to edit the bond cycle performed by the controller.

As can be appreciated, the bond cycle should be maximized to provide the strongest bond possible between the orthodontic bracket400and the tooth. In order to further increase the bond strength, the tooth426can be etched prior to installing the orthodontic bracket400. For example, an etching step can be used to either remove the smear layer of dentin or to roughen the surface of enamel for improved adhesion. In alternative embodiments, the tooth426can further be treated with a pre-bond conditioner, liquid adhesive or surface primer prior to the application of the hot melt dental adhesive layer406.

Again, due to the reversible bond nature of the hot melt dental adhesive layer406, it is easy for the dental professional to remove the orthodontic bracket after treatment. For example, to remove the bracket, a laser light or heat wand can direct heat or energy towards the bracket wherein the hot melt dental adhesive layer406is heated to a liquid/semi-liquid state and the orthodontic bracket is easily removed. The handpiece illustrated inFIGS. 4B-4Dmay be used to provide radiant energy from the removal of the bracket, or devices as described inFIGS. 3A-3Bmay also be used. Any residual hot melt dental adhesive remaining on the tooth426can be rubbed away with a gloved hand while still in the unhardened state, or if it becomes hardened the laser can be heat activated again to loosen any residual hot melt adhesive and then removed by a gloved hand or dental instrument.

FIGS. 5A and 5Billustrated another example embodiment of a handpiece512configured to install an orthodontic bracket500. The handpiece512is similar to the handpiece described with respect toFIGS. 4B-4Dand includes a handle portion514and a tip portion518. However the tip portion518includes a mounting surface522that includes a geometric interface to interface directly with the orthodontic bracket500. In particular, and as illustrated inFIG. 5A, the mounting surface522can include raised portions and indentations that allow the orthodontic bracket500to physically interface with the tip portion518to allow the tip portion to temporarily secure the orthodontic bracket500during the installation process.

In greater detail,FIG. 5Billustrates that the orthodontic bracket500can include extended portions504that rise up away from a base portion. The extended portions are correlated with the tip portion518such that the extended portions504slide into the mounting surface522. The mounting surface522and the extended portions504can be dimensioned to provide a weak slip fit such that the mounting surface522is able to secure orthodontic bracket500and at least support the weight of the bracket. Thus, when the orthodontic bracket500is secured in the tip portion518a hot melt dental adhesive layer506is positioned to easily be pressed against a patient's tooth.

For example,FIG. 5Cillustrates the orthodontic bracket500secured within the tip portion518with the hot melt dental adhesive layer506positioned to be pressed against a tooth526. Once pressed against the tooth, the dental professional can initiate a bonding cycle as described above, which can supply radiant energy524that passes through the orthodontic bracket500and is absorbed by the hot melt dental adhesive layer506. The bonding cycle then proceeds accordingly as described above with respect toFIGS. 4C-4D.

Once all a complete set of orthodontic brackets are installed, often times the patient can experience discomfort. For example, orthodontic brackets have rough or sharp edges that irritate the opposing soft tissue, which usually results in the patient developing painful sores and cankers. In another example embodiment of the present invention, shown inFIG. 6, a layer of hot melt dental adhesive can be applied to coat an orthodontic bracket for the purpose of creating a smooth coating that is removable.

As illustrated inFIG. 6, a dental professional can use a delivery device600(e.g., seeFIG. 2Aand corresponding discussion) to apply a coating of hot melt dental adhesive602over an orthodontic bracket604. The hot melt dental adhesive is then allowed to cool into a hardened state by either allowing it to cool when exposed to atmospheric air, or alternatively water from a dental syringe can by sprayed over the hot melt dental adhesive to accelerate the cooling process. When the hot melt dental adhesive cools, the coating602remains fixed to the orthodontic bracket604providing a permanent solution to protect the patient from discomfort throughout the orthodontic treatment period.

AlthoughFIG. 6only illustrates the hot melt dental adhesive applied to the orthodontic bracket604, a dental professional can use the hot melt dental adhesive to coat any fixture, bracket, wire, or even tooth roughness so as to protect the tissue within a patient's mouth.

Again, because of the reversible nature of the hot melt dental adhesive, once the orthodontic treatment is complete, the solid hot melt dental adhesive can be easily removed by heating the hot melt dental adhesive with a heat source (e.g., a laser or heat wand), and then physically removing the hot melt dental adhesive from the bracket.

As discussed above, the hot melt dental adhesive can include an active medicament ingredient, and therefore can be applied directly to the surface of a tooth to provide a treatment, as illustrated inFIGS. 7A and 7B. For example, the hot melt dental adhesive can be formed into a treatment rod702and fed into a delivery device700. The delivery device can melt the treatment rod702and allow a dental professional to express the treatment material to a particular location on a patient's tooth. For example, as illustrated inFIG. 7A, the treatment material can be applied into the mesial areas of the teeth and then outward forming a dollop of material on buccal and lingual surfaces of the tooth, wherein the dollops on both sides of the tooth are held in place physically by the connection within the mesial gap.

When allowed to sufficiently cool and hardened, the treatment material remains on and between the teeth releasing beneficial active medicament ingredients into the saliva until such time that the active ingredients become spent. When the active ingredients are spent, the treatment material is easily removed by using a laser and/or heat source to re-melt the treatment material such that the dollop becomes separated from its mesial attachment and is easily pulled away from the teeth.

An alternative method of placing the treatment material is illustrated inFIG. 7B. As shown inFIG. 7B, the treatment material704is bonded to an etched surface of a tooth and held in place by adhesion forces during the treatment regime. When the active ingredients become spent, the treatment material is easily removed by using a laser or other heat source to re-melt the treatment plastic and easily removing the treatment plastic from the tooth with a gloved hand or dental tool.

Notwithstanding all the various applications for which the hot melt dental materials described herein can be used,FIGS. 8A and 8Billustrate another example embodiment of a handpiece that can be used in combination with the hot melt dental materials. In particular, the handpieces illustrated inFIGS. 8A and 8Bcan be used to apply and/or remove orthodontic bracket, treatment materials, and any other application of the hot melt dental material described herein. Specifically, the handpieces shown and described inFIGS. 8A and 8Billustrate an embodiment that includes an assembly to optically control a laser beam such that the surface area affected by the laser beam is controlled. In other words, the optical control of the handpieces allows additional precise control of the location of radiant energy produced from laser handpieces or similar devices.

FIG. 8Aillustrates an example embodiment of a linear handpiece800. As illustrated inFIG. 8A, the linear handpiece800includes a hollow housing802configured such that a sheathed optical fiber804can enter the housing802on one end and run through the housing to the other end. The linear handpiece800further includes a clasp806that can be tightened or engaged to securely hold the sheathed optical fiber804within the housing802.

As further illustrated inFIG. 8A, the linear handpiece800further includes a tip assembly808at the end opposite of the clasp. As illustrated in detail A, the tip assembly can include a stop810. As illustrated, the stop810can be as simple as a narrowing of the hollow portion of the housing802to a dimension that an unsheathed optical fiber812can extend past the stop810, but the sheathed optical fiber804is precluded from extending past the stop810.

The unsheathed optical fiber812extends past the stop and through and interface member814such that the optical unsheathed optical fiber extends at least to the end of the interface member814. A dental professional can trim or remove any excess unsheathed optical fiber that extends past the interface member.

A tip portion816can be removably attached to the interface member814. For example, the tip portion816can screw, snap, or other latch onto the interface member814. The tip portion can be used to control the cross-sectional area of the beam to be predetermined size. For example, as the distance between the end of the optical fiber increases, the cross-sectional area of the beam increases. Thus, the tip portion816can be made with a specific length such that the beam cross-sectional area is a preferred size at that particular distance away from the optical fiber.

Similarly, the tip portion816can be configured with optic properties that control the beam path of the laser. In one example embodiment, the tip portion widens the cross-sectional area of the beam such that the beam is a predetermined size. For example, and as illustrated inFIG. 8A, the tip portion816can optically alter or direct the laser beam such that the entire surface of an orthodontic bracket818is exposed to the radiant energy provided by the laser beam. Various tip portions816can be developed so that the dental professional can interchange tip portions to customize the effect of the radiant energy emitted from the linear handpiece800.

Although the linear handpiece800may be very useful for working on a patient's front teeth, a curved handpiece820illustrated inFIG. 8Bcan be useful for working on a patients back teeth. Similar to the linear handpiece800, the curved handpiece820includes a hollow housing802through which a sheathed optical fiber804extends. The curved handpiece820further includes a clasp806to secure the sheathed optical fiber804within the housing802. Different from the linear handpiece800, the curved handpiece820includes a curved tip assembly822.

As illustrated in detail B, the curved tip assembly is configured to direct the radiant energy at an angle with respect to the housing802.FIG. 8Billustrates that the curved tip assembly822can be angled at about 90 degrees with respect to the housing802, however, in alternative embodiments the curved tip assembly822can have various other angles as desired.

Notwithstanding the various angles of the curved tip assembly822, the curved tip assembly includes similar components as with the tip assembly808discussed above. In particular, the curved tip assembly822can include a stop810. As illustrated, the stop810can be as simple as a narrowing of the hollow portion of the housing802to a dimension that an unsheathed optical fiber812can extend past the stop810, but the sheathed optical fiber804is precluded from extending past the stop810.

The unsheathed optical fiber812can extend past the stop and through an interface member814such that the unsheathed optical fiber812extends at least to the end of the interface member814. A dental professional can trim or remove any excess unsheathed optical fiber812that extends past the interface member814.

A tip portion816can be removably attached to the interface member814. For example, the tip portion816can screw, snap, or other latch onto the interface member814. The tip portion816is configured with optical properties that control the beam path of the laser. In one example embodiment, the tip portion816can increase the cross-sectional area of the beam such that the beam is a predetermined size. For example, and as illustrated inFIG. 8B, the tip portion816can optically alter or direct the laser beam such that the entire surface of an orthodontic bracket818is exposed to the radiant energy provided by the laser beam. Various tip portions816can be developed so that the dental professional can interchange tip portions to customize the effect of the radiant energy emitted from the linear handpiece800.