Oral appliance formed of polyurethane-based resin including ionically charged modifier

Abstract

An oral appliance configured for temporary use in a patient's mouth. The oral appliance has an oral appliance body formed from an ionic polyurethane-based resin, which is a reaction product of ingredients including a diisocyanate, a diol chain extender, a polyglycol, and an ionically charged modifier. An ionic active agent is ionically bound to the ionically charged modifier. This may be done by solution imbibing technique or bulk mixing (e.g., thermal compounding or solvent mixing) technique. The ionic active agent may include fluoride ions. The ionic active agent may include an antimicrobial agent. The ionic active agent may include one or more essential oils.

Description

ORAL APPLIANCE FORMED OF POLYURETHANE-BASED RESIN INCLUDING IONICALLY CHARGED MODIFIERBACKGROUND

[0001] The disclosed invention relates to an oral appliance fabricated of a polyurethane-based resin including one or more ionically charged modifiers which render the polyurethane-based resin ionically charged. One or more ionic active agents are bound to the ionic polyurethane-based resin. During use, the ionic active agents are released to provide desirable oral hygiene properties.SUMMARY

[0002] The present disclosure relates generally to an oral appliance configured for temporary use in a patient’s mouth. The oral appliance includes an oral appliance body formed from an ionic polyurethane-based resin, which is a reaction product of ingredients comprising a diisocyanate, a diol chain extender, a polyglycol, and an ionically charged modifier. Ionically charged modifiers render the polyurethane-based resin ionically charged. An ionic active agent is ionically bound to the ionically charged modifier.

[0003] In some embodiments, the ionically charged modifier comprises an anionic modifier. In some embodiments, the anionic modifier comprises an anionic functional moiety of — SO3-, — COO-, or combinations thereof. In some embodiments, the anionic modifier comprises bis- 1,4- ((2-hydroxypropoxy)-2-propoxy)-butane sulfonate sodium salt (SULFADIOL®-7Q), 2,3- dihydroxypropane-1 -sulfonate sodium salt, N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate sodium salt, 2,2-bis(hydroxy-methyl)-propionic acid, 2,2-bis(hydroxymethyl)-butyric acid (BHMBA), or combinations thereof.

[0004] In some embodiments, the ionically charged modifier comprises a cationic modifier.In some embodiments, the cationic modifier comprises a cationic functional moiety of quaternaryammonium. In some embodiments, the cationic modifier comprises bi s(2-hydroxy ethyl) dimethylammonium chloride (BHDAC).

[0005] In some embodiments, the ionically charged modifier comprises at least one anionic modifier and at least one cationic modifier.

[0006] In some embodiments, the ionic active agent comprises fluoride ions. In some embodiments, the fluoride ions are obtained from sodium fluoride, stannous fluoride, or monofluorophosphate.

[0007] In some embodiments, the ionic active agent comprises an antimicrobial agent. In some embodiments, the antimicrobial agent comprises chlorhexidine ions. In some embodiments, the antimicrobial agent comprises cetylpyridinium ions.

[0008] In some embodiments, the ionic active agent comprises one or more essential oils. In some embodiments, the one or more essential oils comprise essential oils selected from eucalyptol, menthol, menthone, carvone, thymol, cinnamaldehyde, eugenol, and methyl salicylate. In some embodiments, the ionic active agent comprises one or more flavors selected from spearmint, peppermint, and cinnamon.

[0009] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. It should be understood that the various embodiments are not limited to the arrangements and instrumentality shown in the drawings. It should also be understood that the embodiments may be combined, or that other embodiments may be utilized and that structural changes, unless so claimed, may be made without departing from the scope of the various embodiments of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0010] Example embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

[0011] Fig. 1 is a perspective view of an exemplary oral appliance.

[0012] Fig. 2 is a perspective view of an exemplary toothbrush oral appliance.

[0013] Fig. 3 is a plan view of an exemplary dental floss / dental pick oral appliance.DESCRIPTION OF EMBODIMENTS

[0014] The disclosure relates to an oral or dental appliance having an appliance body which is formed of a polyurethane-based resin including an ionically charged modifier. The ionically charged modifier renders the polyurethane-based resin ionically charged. The appliance body is exposed to one or more ionic active agents. The ionically charged moi eties bond to the ionic active agents. The appliance body is placed in a user’ s mouth for a period of time which may range from 5 or more minutes to several hours, including while sleeping overnight and during the day. During use the ionic active agents are to provide beneficial oral hygiene. The appliance body may be refreshed and reused upon repeated exposure to one or more ionic active agents.

[0015] In some embodiments, the ionic active agent comprises fluoride ions. Fluoride ions are known to benefit oral health and hygiene. Slow elution of fluoride ions may inhibit or reverse the initiation and progression of dental caries (tooth decay) and strengthen tooth enamel. Any suitable source of fluoride ions may be used. In some embodiments, the source of fluoride ions may include sodium fluoride, stannous fluoride, and monofluorophosphate. Daily release of fluoride ions may range from 0.5 mg to 4 mg.

[0016] In some embodiments, the ionic active agent comprises an antimicrobial agent. Slow elution of an antimicrobial agent may inhibit or help control plaque, gingivitis, and periodontal disease. Any antimicrobial agent suitable for oral use may be used. In some embodiments, the antimicrobial agent comprises chlorhexidine ions. In some embodiments, the antimicrobial agent comprises cetylpyridinium ions. In some embodiments, oral appliance may be an orthodontic tool, such as a mouth guard, retainer, or teeth aligner. The oral appliance may be configured to elute or release the antimicrobial agent at a specific and proper location to provide desired antimicrobial activity. A targeted antimicrobial release permits antimicrobial treatment of harmful bacteria while leaving beneficial bacteria within the mouth untreated.

[0017] In some embodiments, the ionic active agent comprises one or more essential oils. Essential oils are useful to provide flavor and to provide antimicrobial activity. In some embodiments, the one or more essential oils comprise essential oils selected from eucalyptol, menthol, menthone, carvone, thymol, cinnamaldehyde, eugenol, and methyl salicylate. In some embodiments, the ionic active agent comprises one or more flavors selected from spearmint, peppermint, and cinnamon. In spearmint, the main flavor compounds are carvone and eucalyptol. Spearmint essential oils possess antimicrobial activity. In peppermint, the main flavor compounds are menthol, menthone, and eucalyptol. Peppermint essential oils possess antimicrobial activity. In cinnamon, the main flavor compounds are cinnamaldehyde and eugenol. Cinnamon essential oils possess antimicrobial activity.

[0018] Nonlimiting examples of the polyurethane-based resin including an ionically charged modifier are disclosed in US 2022 / 0265905 Al, US 2022 / 0265906 Al, US 2022 / 0265904 Al, US2023 / 0166007 Al, and US 2023 / 0166001 Al, which publications are incorporated by reference.

[0019] The polyurethane-based resin is a reaction product of ingredients comprising: a diisocyanate; a diol chain extender; a polyglycol; and an ionically charged modifier incorporated into a backbone, as a side chain, or both of the polyurethane-based resin. Embodiments include the ionically charged modifier. The ionically charged modifier may be an anionic modifier, a cationic modifier, a combination of anionic and cationic modifiers, or a zwitterionic modifier.

[0020] Exemplary anionic modifiers include 2,2-bis(hydroxymethyl) butyric acid (BHMBA) and / or bis-l,4-(2-hydroxypropoxy)-2-propoxy)-butane sulfonate sodium salt (SULFADIOL®- 7Q).

[0021] An exemplary cationic modifier includes bis(2-hydroxyethyl) dimethylammonium chloride (BHDAC).

[0022] An exemplary combination of anionic and cationic modifiers includes bis-l,4-((2- hydroxypropoxy)-2-propoxy)-butane sulfonate sodium salt (SULFADIOL®-7Q) as the anionic modifier; and bi s(2-hydroxy ethyl) dimethylammonium chloride (BHDAC) as the cationic modifier.

[0023] The following terms shall have, for the purposes of this application, the respective meanings set forth below.

[0024] Polyglycols include but are not limited to: polyalkylene glycol, polyester glycol, and polycarbonate glycol. A nonlimiting specific example of polyalkylene glycol is polyether glycol. A polyether glycol is a moderate molecular weight oligomer derived from an alkylene oxide, containing both ether linkages and glycol termination.

[0025] A chain extender is a short chain (low molecular weight) branched or unbranched diol, diamine or amino alcohol of up to 10 carbon atoms or mixtures thereof. Such hydroxyl- and / oramine-terminated compounds are used during polymerization to impart desired properties to a polymer.

[0026] An ionically charged modifier is a compound exhibiting a charge that enhances a basic polyurethane structure of a diisocyanate; a diol chain extender; and a polyglycol. The ionically charged modifier herein comprises an anionic, a cationic, or a combination of anionic and cationic modifiers or a zwitterionic modifier that make the polyurethane ionic in nature to render the resulting oral appliance with desirable properties. The desired properties include passive reduction of bacterial biofilm colony formation and antifouling property.

[0027] The anionic functional moieties include but are not limited to — SO3 and / or — COO . The cationic functional moieties include but are not limited to quaternary ammonium. The anionic and cationic functional moieties can be incorporated into a backbone, as a side chain, or both. The anionic and cationic functional moieties can be delivered as a polyglycol or as a diol chain extender, or as a diisocyanate.

[0028] In some embodiments, the ionic active agent comprises an antimicrobial agent. Antimicrobial agents that can be used for bonding with anionic functional moieties include any cationic antibiotics. Nonlimiting examples of cationic antimicrobials include chlorhexidine acetate, chlorhexidine gluconate, silver sulfadiazine, benzalkonium chloride, cetylpyridinium chloride, etc. In addition, cationic quaternary ammonium and guanidine containing biocides, cationic antimicrobial polymers, antimicrobial peptides or peptide-mimics can also be ionically bonded with anionic functional moieties of the polyurethane to actively and / or passively provide advantages of enhanced surface properties including antimicrobial properties.

[0029] Antimicrobial agents that can be used for bonding with cationic functional moieties include any anionic antimicrobials. Nonlimiting examples of anionic antimicrobials include cioxacillin salt, cefoxitin salt, cefazolin salt, penicillin salt, or derivatives thereof.

[0030] In some embodiments, the ionic active agent comprises fluoride ions. In some embodiments, the fluoride ions are obtained from sodium fluoride, stannous fluoride, or monofluorophosphate.

[0031] In some embodiments, the ionic active agent comprises one or more essential oils. In some embodiments, the one or more essential oils comprise essential oils selected from eucalyptol, menthol, menthone, carvone, thymol, cinnamaldehyde, eugenol, and methyl salicylate. In some embodiments, the ionic active agent comprises one or more flavors selected from spearmint, peppermint, and cinnamon.

[0032] Ionic bonding of active agents can be achieved by solution imbibing technique or bulk mixing (e.g., thermal compounding or solvent mixing) technique. As a result, ionic active agents would be ionically bonded not only on ionic thermoplastic polyurethane (TPU) surface but also in the bulk ionic TPU to render the resulting oral appliance desirable properties.

[0033] A low-surface energy modifying oligomer (moderate molecular weight), as described in WO 2020 / 068617 Al and WO 2020 / 068619 Al, which is optional in embodiments herein, is a compound that enhances a basic polyurethane structure of a diisocyanate; a diol chain extender; a polyglycol; and an ionically charged modifier. Modifying oligomers, which are different from polyglycols and ionically charged modifiers, contain functional moieties (e.g., fluoroether and / or silicone) that migrate onto the polyurethane surface to render the resulting oral appliance with additional desirable surface properties including self-lubricating and antifouling property. Modifying oligomers may have at least one, preferably two, or more than two, alcohol moieties(C-OH). The alcohol moieties may be located along a backbone of the oligomer. The alcohol moieties may be located at an end of the oligomer. In a detailed embodiment, the oligomer terminates with an alcohol moiety.

[0034] Isocyanate index is defined as the molar ratio of the total isocyanate groups in the diisocyanate to the total hydroxyl and / or amino groups presented in polyols and extenders. In general, polyurethane becomes harder with an increasing isocyanate index. There is, however, a point beyond which the hardness does not increase, and the other physical properties begin to deteriorate.

[0035] Incorporation into backbone means that ionic functionalities (e.g., — SO and / or — COO and quaternary ammonium) are directly linked to the polyurethane backbone chain; incorporation as a side chain means that there is at least one carbon chain spacer between ionic functionalities and the polyurethane backbone chain. The polyurethane-based resin comprises a hard segment content in a range of from 25 % to 75 % by weight and a soft segment content of the resin in a range of from 75 % to 25 % by weight.

[0036] In one or more embodiments, the anionic modifier is incorporated into the polyurethane-based resin in an amount of greater than or equal to: 0.01 wt. %, 0.1 wt. %, 0.5 wt. %, 1 wt. %, 1.5 wt. %, 2 wt. %, 3 wt. %, 4 wt. % and 4.5 wt. % of the overall composition of the polyurethane-based resin.

[0037] In one or more embodiments, the anionic modifier is incorporated into the polyurethane-based resin in an amount of less than or equal to: 75 wt. %, 50 wt. %, 25 wt. %, 10 wt. %, 9.5 wt. %, 9.0 wt. %, 8.5 wt. %, 8.0 wt. %, 7.5 wt. %, 7.0 wt. %, 6.5 wt. % or 6.0 wt. % of the overall composition of the polyurethane-based resin.

[0038] In one or more embodiments, the anionic modifier is incorporated into the polyurethane-based resin in an amount ranging from greater than or equal to 0.01 to less than or equal to 75 wt. %, and all values and subranges therebetween, including greater than or equal to0.5 to less than or equal to 50 wt. %, greater than or equal to 1 to less than or equal to 25 wt. %, and all values and subranges there between; including: greater than or equal to: 0.01 wt. %, 0.1 wt. %, 0.5 wt. %, 1 wt. %, 1.5 wt. %, 2 wt. %, 3 wt. %, 4 wt. % and 4.5 wt. % to less than or equal to: 75 wt. %, 50 wt. %, 25 wt. %, 10 wt. %, 9.5 wt. %, 9.0 wt. %, 8.5 wt. %, 8.0 wt. %, 7.5 wt. %, 7.0 wt. %, 6.5 wt. %, 6.0 wt. % of the overall composition of the polyurethane-based resin.

[0039] In one or more embodiments, the cationic modifier is incorporated into the polyurethane - based resin in an amount of greater than or equal to: 0.01 wt. %, 0.1 wt. %, 0.5 wt. %, 1 wt. %, 1.5 wt. %, 2 wt. %, 3 wt. %, 4 wt. % and 4.5 wt. % of the overall composition of the polyurethane-based resin.

[0040] In one or more embodiments, the cationic modifier is incorporated into the polyurethane - based resin in an amount of less than or equal to: 10 wt. %, 9.5 wt. %, 9.0 wt. %, 8.5 wt. %, 8.0 wt. %, 7.5 wt. %, 7.0 wt. %, 6.5 wt. % or 6.0 wt. % of the overall composition of the polyurethane-based resin.

[0041] In one or more embodiments, the cationic modifier is incorporated into the polyurethane-based resin in an amount ranging from greater than or equal to 0.01 to less than or equal to 10 wt. %, and all values and subranges therebetween, including greater than or equal to 0.5 to less than or equal to 7.5 wt. %, greater than or equal to 1 .0 to less than or equal to 6.0 wt. %, and all values and subranges therebetween; including: greater than or equal to : 0.01 wt. %, 0.1 wt. %, 0.5 wt. %, 1 wt. %, 1.5 wt. %, 2 wt. %, 3 wt. %, 4 wt. % and 4.5 wt. % to less than or equalto: 10 wt. %, 9.5 wt. %, 9.0 wt. %, 8.5 wt. %, 8.0 wt. %, 7.5 wt. %, 7.0 wt. %, 6.5 wt. %, 6.0 wt. % of the overall composition of the polyurethane-based resin.

[0042] In one or more embodiments, the combination of anionic and cationic modifiers or zwitterionic modifier is incorporated into the polyurethane-based resin in an amount of greater than or equal to: 0.01 wt. %, 0.1 wt. %, 0.5 wt. %, 1 wt. %, 1.5 wt. %, 2 wt. %, 3 wt. %, 4 wt. % and 4.5 wt. % of the overall composition of the polyurethane-based resin.

[0043] In one or more embodiments, the combination of anionic and cationic modifiers or zwitterionic modifier is incorporated into the polyurethane-based resin in an amount of less than or equal to: 10 wt. %, 9.5 wt. %, 9.0 wt. %, 8.5 wt. %, 8.0 wt. %, 7.5 wt. %, 7.0 wt. %, 6.5 wt. % or 6.0 wt. % of the overall composition of the polyurethane-based resin.

[0044] In one or more embodiments, the combination of anionic and cationic modifiers or zwitterionic modifier is incorporated into the polyurethane-based resin in an amount ranging from greater than or equal to 0.01 to less than or equal to 10 wt. %, and all values and subranges therebetween, including greater than or equal to 0.5 to less than or equal to 7.5 wt. %, greater than or equal to 1.0 to less than or equal to 6.0 wt. %, and all values and subranges there between; including: greater than or equal to: 0.01 wt. %, 0.1 wt. %, 0.5 wt. %, 1 wt. %, 1.5 wt. %, 2 wt. %, 3 wt. %, 4 wt. % and 4.5 wt. % to less than or equal to: 10 wt. %, 9.5 wt. %, 9.0 wt. %, 8.5 wt. %, 8.0 wt. %, 7.5 wt. %, 7.0 wt. %, 6.5 wt. %, 6.0 wt. % of the overall composition of the polyurethane- based resin.

[0045] The anionic modifier may comprise one or more of — SO3 and / or — COO functional moi eties. Nonlimiting examples of the anionic modifiers are: bis-l,4-((2-hydroxypropoxy)-2- propoxy)-butane sulfonate sodium salt (SULFADIOL®-7Q); 2, 3-dihydroxypropane-l -sulfonatesodium salt; N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate sodium salt; 2,2-bis(hydroxy- methyl)propionic acid; 2,2-bis(hydroxymethyl) butyric acid (BHMBA); or combinations thereof.

[0046] The cationic modifier may comprise one or more quaternary ammonium functional moieties. A nonlimiting example of the cationic modifier with quaternary ammonium functional moiety is bis(2-hydroxyethyl) dimethylammonium chloride (BHDAC).

[0047] The zwitterionic modifier may comprise both anionic and cationic functional moieties. Nonlimiting examples of the zwitterionic modifier with both anionic and cationic functional moieties are: N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid; N,N-bis(2 -hydroxy ethylglycine; or combinations thereof.

[0048] The polyurethane-based resin may be a reaction product of a diisocyanate; a diol chain extender; a polyglycol; and an anionic modifier, a cationic modifier, or a combination of anionic and cationic modifiers (or zwitterionic modifier). In an embodiment, the polyurethane-based resin is a reaction product of: a diisocyanate; a diol chain extender, a polyglycol; a bis-l,4-(2- hydroxypropoxy)-2-propoxy)-butane sulfonate sodium salt (SULFADIOL®-7Q) as the anionic modifier; and a bi s(2-hydroxy ethyl) dimethylammonium chloride (BHDAC) as the cationic modifier. In an embodiment, the polyurethane-based resin is a reaction product of: a diisocyanate; a diol chain extender; a polyglycol; a 2, 3-dihydroxypropane-l -sulfonate sodium salt as the anionic modifier; and a bis(2-hydroxyethyl) dimethylammonium chloride (BHDAC) as the cationic modifier. In an embodiment, the polyurethane-based resin is a reaction product of: a diisocyanate; a diol chain extender; a polyglycol; a N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate sodium salt as the anionic modifier; and a bis(2-hydroxy ethyl) dimethylammonium chloride (BHDAC) as the cationic modifier. In an embodiment, the polyurethane-based resin is a reaction product of: a diisocyanate; a diol chain extender; a polyglycol; a 2,2-bis(hydroxymethyl)propionic acid as theanionic modifier; and a bis(2 -hydroxy ethyl) dimethylammonium chloride (BHDAC) as the cationic modifier. In an embodiment, the polyurethane-based resin is a reaction product of a diisocyanate; a diol chain extender; a polyglycol; a 2,2-bis(hydroxymethyl) butyric acid (BHMBA) as the anionic modifier; and a bis(2-hydroxyethyl) dimethylammonium chloride (BHDAC) as the cationic modifier. In an embodiment, the polyurethane-based resin is a reaction product of: a diisocyanate; a diol chain extender; a polyglycol; an ionic modifier selected from one or multiple anionic modifiers, one or multiple cationic modifiers, and a combination of one or multiple anionic modifiers and one or multiple cationic modifiers.

[0049] POLYURETHANES

[0050] Thermoplastic polyurethanes (TPUs) suitable for oral appliances are typically synthesized from three basic components: a diisocyanate, a polyglycol, and a chain extender, usually a low molecular weight diol, diamine, amino alcohol or water. If the chain extender is a diol, the polyurethane consists entirely of urethane linkages. If the extender is water, amino alcohol or diamine, both urethane and urea linkages are present, which results in a polyurethane urea (PUU). Inclusion of an amine-terminated polyether to the polyurethane synthesis also results in a polyurethane urea.

[0051] Polyurethane and polyurea chemistries are based on the reactions of isocyanates with other hydrogen-containing compounds, where isocyanates are compounds having one or more isocyanate groups (-N=C=O). Isocyanate compounds can be reacted with water (H2O), alcohols (R-OH), amines (RX-NH(3-X)), ureas (R-NH-CONH2), and amides (R-CONH2). Certain polyurethanes may be thermoplastic elastomers (TPE), whereas other compositions may be highly cross-linked.

[0052] Thermoplastic polyurethanes comprise two phases or microdomains conventionally termed hard segments and soft segments, and as a result are often referred to as segmented polyurethanes. The hard segments, which are generally of high crystallinity, form by localization of the portions of the polymer molecules which include the diisocyanate and chain extender(s). The soft segments, which are generally either non-crystalline or of low crystallinity, form from the polyglycol or the optional amine-terminated polyether. The hard segment content is determined by the weight percent of diisocyanate and chain extender in the polyurethane composition, and the soft segment content is the weight percent of polyglycol or polydiamine. The thermoplastic polyurethanes may be partly crystalline and / or partly elastomeric depending on the ratio of hard to soft segments. One of the factors which determine the properties of the polymer is the ratio of hard and soft segments. In general, the hard segment contributes to hardness, tensile strength, impact resistance, stiffness and modulus while the soft segment contributes to water absorption, elongation, elasticity and softness.

[0053] The polyurethanes may be produced by the reaction of: a diisocyanate, a diol chain extender, at least one polyglycol, at least one ionically-charged modifier (an anionic modifier, a cationic modifier, a combination of anionic and cationic modifiers or a zwitterionic modifier), and optionally, a low-surface energy modifying oligomer. The polyurethane may have a hard segment content between 25 % and 75 % by weight, where a hard segment is the portion(s) of the polymer molecules which include the diisocyanate and the extender components, which are generally highly crystalline due to dipole-dipole interactions and / or hydrogen bonding. In contrast, the soft segments are formed from the polyglycol portions and optionally the low-surface energy modifying oligomers between the diisocyanate of the polymer chains and generally are either amorphous or only partially crystalline due to the characteristics of the polyglycol(s) andmodifying oligomer (s). In an embodiment, the hard segment content may be in the range of from 25 % to 75 % and the soft segment content may be in the range of from 75 % to 25 %.

[0054] Herein, the ionically charged modifier is an anionic modifier, a cationic modifier, a combination of anionic and cationic modifiers or a zwitterionic modifier, whose anionic and cationic functional moieties can be introduced into soft segments of the TPU materials using polyglycols and / or optional low-surface energy modifying oligomers with ionic functionalities or hard segments of TPU materials using diol chain extenders and / or diisocyanates with ionic functionalities.

[0055] Nonlimiting examples of the anionic functional moieties of the ionic polyurethane include carboxylate — COO , sulfonate — SOs or combinations thereof. In an embodiment, anionic moieties are introduced into hard segment of the TPU material using diol chain extender with anionic functionalities, e.g., 2,2-bis(hydroxymethyl) butyric acid (BHMBA). In another embodiment, anionic moieties are introduced into soft segment of the TPU material using polyglycol with anionic functionalities, e.g., bis-l,4-((2-hydroxypropoxy)-2-propoxy)-butane sulfonate sodium salt (SULFADIOL®-7Q).

[0056] Nonlimiting examples of the cationic functional moieties of the ionic polyurethane include quaternary ammonium. In an embodiment, cationic moieties are introduced into hard segment of the TPU material using diol chain extender with cationic functionalities, e.g., bis(2- hydroxyethyl) dimethylammonium chloride (BHDAC).

[0057] Polymerization of the polyurethane may be a one-step or two-step copolymerization process. The process may require a catalyst, solvent, other additives, or a combination thereof. The synthesis may also be achieved by a variety of other synthesis techniques with or without catalyst / solvent understood by those skilled in the art. The ionic polyurethane may also beformulated from a blend of two or more different polyurethane compositions, e.g., blending / compounding of existing anionic polyurethanes and cationic polyurethanes.

[0058] The diisocyanate may be selected from the group consisting of: an aliphatic diisocyanate, alicyclic diisocyanate and an aromatic diisocyanate. In various embodiments, the diisocyanate may be selected from the group consisting of: 4,4'-diphenylmethane diisocyanate (MDI), toluene diisocyanate (TDI), isophorone diisocyanate (IPDI), methylene-bis(4- cyclohexylisocyanate) (HMDI), or combinations thereof.

[0059] The diol chain extender may be selected from the group consisting of: ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, and alicyclic glycols having up to 10 carbon atoms.

[0060] The polyglycol may be selected from the group consisting of: polyalkylene glycol, polyester glycol, polycarbonate glycol, and combinations thereof. In an embodiment, the polyglycol comprises the polyalkylene glycol. In an embodiment, the polyalkylene glycol comprises a polytetramethylene ether glycol (PTMEG). A further polyalkylene glycol may be polyethylene glycol (PEG) and / or polypropylene glycol (PPG).

[0061] BONDING OF ACTIVE AGENTS WITH POLYURETHANE-BASED RESINS

[0062] In one or more embodiments, the polyurethane-based resin is bound to an ionic agent through ionic bonding. In various embodiments, the ionic agent comprises one or more of: an antimicrobial agent, such as cetylpyridinium chloride and chlorhexidine, fluoride ions, essential oils, such as eucalyptol, menthol, menthone, carvone, thymol, cinnamaldehyde, eugenol, and methyl salicylate, and flavors, such as spearmint, peppermint, and cinnamon.

[0063] Ionic bonding of active agents can be achieved by solution imbibing technique or bulk mixing (e.g., thermal compounding or solvent mixing) technique. As a result, ionic active agents,such as antimicrobial agents, fluoride ions, essential oils, and / or flavors, would be ionically bonded not only on ionic TPU surface but also in the bulk ionic TPU to render the resulting oral appliance desirable properties, including antimicrobial and / or beneficial oral or dental properties.

[0064] EXEMPLARY POLYURETHANE-BASED RESINS

[0065] Oral appliances are formed from an ionic polyurethane-based resin, which may be an anionic polyurethane, a cationic polyurethane, or a blend of an anionic polyurethane and a cationic polyurethane at a certain ratio. The hard segment content of ionic polyurethane is in the range of from 25 % to 75 % by weight, and the soft segment content of the resin is in the range of from 75 % to 25 % by weight.

[0066] In one or more embodiments, the anionic polyurethane has the following ingredients: the diisocyanate comprises 4,4'-diphenylmethane diisocyanate (MDI); the diol chain extender comprises 1,4-butanediol; the polyglycols comprise a polytetramethylene ether glycol (PTMEG) with average MW in the range of from 250 Da to 2900 Da (n = 3-40); the optional low-surface energy modifying oligomers comprise a diol -containing perfluoropolyether and / or a monofunctional polysiloxane; and the anionic modifier comprises 2,2-bis(hydroxymethyl) butyric acid (BHMBA) and / or bis-l,4-((2-hydroxypropoxy)-2-propoxy)-butane sulfonate sodium salt (SULFADIOLO-7Q).

[0067] In one or more embodiments, the cationic polyurethane has the following ingredients: the diisocyanate comprises 4,4'-diphenylmethane diisocyanate (MDI); the diol chain extender comprises 1,4-butanediol; the polyglycols comprise a polytetramethylene ether glycol (PTMEG) with average MW in the range of from 250 Da to 2900 Da (n = 3-40); the optional low surface energy modifying oligomers comprise a diol -containing perfluoropoly ether and / or amonofunctional polysiloxane; and the cationic modifier comprises bi s(2hydroxy ethyl) dimethylammonium chloride (BHDAC).

[0068] A removable oral or dental appliance is manufactured with an ionic polyurethane-based resin. Nonlimiting examples of oral appliances include mouth guards, retainers, teeth aligners, toothbrushes, and dental floss / dental pick appliance.

[0069] Fig. 1 is a perspective view of an exemplary oral appliance 100 having an oral appliance body 110 in the form of a retainer or teeth aligner.

[0070] Fig. 2 is a perspective view of an exemplary oral appliance 200 having an oral appliance body 210 in the form of a toothbrush or toothbrush head 220. Toothbrush heads fabricated of an ionic polyurethane-based resin imbibed with fluoride ions and a mint flavored ionic active agent may function as a replacement for toothpaste. The toothbrush head may be imbibed with fluoride ions and release fluoride ions within a user’s mouth to provide a fluoride ion treatment.

[0071] Fig. 3 is a plan view of an exemplary oral appliance 300 having an oral appliance body 310 in the form of a dental floss / dental pick appliance.

[0072] The oral appliance is imbibed with one or more ionic active agents that are beneficial for oral hygiene.

[0073] A user places the oral appliance in his or her mouth for a time period sufficient to permit the one or more ionic active agents to be released to provide beneficial properties. The time period may range from several minutes to several hours, such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 hours, and any time period range between these values. The time period may be while the user sleeps. The time period may be during waking hours.

[0074] Beneficial applications of the oral appliances disclosed herein include, but are not limited to:

[0075] 1 . Strengthen teeth due to slow elution of fluoride ions. Fluoride ions may inhibit or reverse the initiation and progression of dental caries (tooth decay) and strengthen tooth enamel. Any suitable source of fluoride ions may be used. Nonlimiting examples of a source of fluoride ions include sodium fluoride, stannous fluoride, and monofluorophosphate. Daily release of fluoride ions may range from 0.5 mg to 4 mg.

[0076] 2. Chronic bad breath or halitosis: Chronic halitosis is often a result of poor oral hygiene, which can lead to harmful bacteria populations in the mouth. Improved oral hygiene, like brushing, flossing and routine dental cleanings may help. The oral appliance may be imbibed with one or more ionic antimicrobial agents such as cetylpyridinium chloride and chlorhexidine. The oral appliance may be imbibed with one or more essential oils, such as eucalyptol, menthol, menthone, carvone, thymol, cinnamaldehyde, eugenol, and methyl salicylate, which possess antimicrobial activity and which also provide natural flavors such as spearmint or peppermint that may freshen the user’s breath. In spearmint, the main flavor compounds are carvone and eucalyptol. In peppermint, the main flavor compounds are menthol, menthone, and eucalyptol.

[0077] 3. Antimicrobial Affects: The oral appliance may be imbibed with one or more ionic antimicrobial agents such as cetylpyridinium chloride and chlorhexidine. The oral appliance may be imbibed with one or more essential oils, such as eucalyptol, menthol, menthone, carvone, thymol, cinnamaldehyde, eugenol, and methyl salicylate, which possess antimicrobial activity.The antimicrobial agent may be imbibed at a specific location of the oral appliance to provide a targeted antimicrobial activity. Specific bad mouth bacteria that cause bad breath, gingivitis, and gum disease may be targeted, yet still leave beneficial bacteria in place within the mouth.

[0078] The oral appliance may be reused multiple times by imbibing it with a custom flavor or ionic active agent based on a user’s needs or preferences. The ionic active agent could be adjusted and customized for each application.

[0079] The oral appliance may be an orthodontic tool such as a retainer or teeth aligner and provide all of the benefits above into an all-in-one tool.EMBODIMENTS

[0080] Various embodiments are listed below. It will be understood that the embodiments listed below may be combined with all aspects and other embodiments in accordance with the scope of the invention.

[0081] Embodiment 1. An oral appliance configured for temporary use in a patient’s mouth comprising: an oral appliance body formed from an ionic polyurethane-based resin, which is a reaction product of ingredients comprising a diisocyanate; a diol chain extender; a polyglycol; and an ionically charged modifier; and an ionic active agent which is ionically bound to the ionically charged modifier.

[0082] Embodiment 2. The oral appliance of Embodiment 1, wherein the ionically charged modifier comprises an anionic modifier.

[0083] Embodiment 3. The oral appliance of Embodiment 2, wherein the anionic modifier comprises an anionic functional moiety of — SO3-, — COO-, or combinations thereof.

[0084] Embodiment 4. The oral appliance of Embodiment 2, wherein the anionic modifier comprises bis-l,4-((2-hydroxypropoxy)-2-propoxy)-butane sulfonate sodium salt (SULFADIOL®-7Q), 2,3-dihydroxypropane-l-sulfonate sodium salt, N,N-bis(2 -hydroxy ethyl)-2-ami noethanesulfonate sodium salt, 2,2-bis(hydroxy-methyl)-propionic acid, 2,2- bis(hydroxymethyl)-butyric acid (BHMBA), or combinations thereof.

[0085] Embodiment 5. The oral appliance of Embodiment 1, wherein the ionically charged modifier comprises a cationic modifier.

[0086] Embodiment 6. The oral appliance of Embodiment 5, wherein the cationic modifier comprises a cationic functional moiety of quaternary ammonium.

[0087] Embodiment 7. The oral appliance of Embodiment 5, wherein the cationic modifier comprises bis(2-hydroxy ethyl) dimethyl ammonium chloride (BHD AC).

[0088] Embodiment 8. The oral appliance of any previous Embodiment, wherein the ionically charged modifier comprises at least one anionic modifier and at least one cationic modifier.

[0089] Embodiment 9. The oral appliance of Embodiment 1, wherein the ionic active agent comprises fluoride ions.

[0090] Embodiment 10. The oral appliance of Embodiment 9, wherein the fluoride ions are obtained from sodium fluoride, stannous fluoride, or monofluorophosphate.

[0091] Embodiment 11. The oral appliance of Embodiment 1, wherein the ionic active agent comprises an antimicrobial agent.

[0092] Embodiment 12. The oral appliance of Embodiment 11, wherein the antimicrobial agent comprises chlorhexidine ions.

[0093] Embodiment 13. The oral appliance of Embodiment 11, wherein the antimicrobial agent comprises cetylpyridinium ions.

[0094] Embodiment 14. The oral appliance of Embodiment 1, wherein the ionic active agent comprises one or more essential oils.

[0095] Embodiment 15. The oral appliance of Embodiment 14, wherein the one or more essential oils comprise essential oils selected from eucalyptol, menthol, menthone, carvone, thymol, cinnamaldehyde, eugenol, and methyl salicylate.

[0096] Embodiment 16. The oral appliance of Embodiment 1, wherein the ionic active agent comprises one or more flavors selected from spearmint, peppermint, and cinnamon.

[0097] Embodiment 17. The oral appliance of Embodiment 1, wherein the ionic active agent is ionically bound to the ionically charged modifier by a solution imbibing technique wherein the oral appliance body is exposed to an imbibing solution comprising the ionic active agent dissolved in a solvent which is compatible with the polyurethane-based resin.

[0098] Embodiment 18. The oral appliance of Embodiment 1, wherein the ionic active agent is ionically bound to the ionically charged modifier by a bulk mixing technique wherein polyurethane-based resin is mixed with the ionic active agent prior to forming the oral appliance body.

[0099] Other features and advantages of the disclosed invention are apparent from the different examples that follow. The examples below illustrate different aspects and embodiments of the present invention and how to make and practice them. The examples do not limit the claimed invention. Although methods and materials similar or equivalent to those described herein can be used in the practice of the present invention, suitable methods and materials are described below. Based on the present disclosure the skilled artisan can identify and employ other components and methodology useful for practicing the present invention.

[0100] Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments” or "an embodiment" means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least oneembodiment of the invention. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

[0101] Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents.

Claims

CLAIMS1. An oral appliance configured for temporary use in a patient’ s mouth comprising: an oral appliance body formed from an ionic polyurethane-based resin, which is a reaction product of ingredients comprising a diisocyanate; a diol chain extender; a polyglycol; and an ionically charged modifier; and an ionic active agent which is ionically bound to the ionically charged modifier.

2. The oral appliance of claim 1, wherein the ionically charged modifier comprises an anionic modifier.

3. The oral appliance of claim 2, wherein the anionic modifier comprises an anionic functional moiety of — SO3 , — COO , or combinations thereof.

4. The oral appliance of claim 2, wherein the anionic modifier comprises bis-l,4-((2- hydroxypropoxy)-2-propoxy)-butane sulfonate sodium salt (SULFADIOL®-7Q), 2,3- dihydroxypropane-1 -sulfonate sodium salt, N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate sodium salt, 2,2-bis(hydroxy-methyl)-propionic acid, 2,2-bis(hydroxymethyl)-butyric acid (BHMBA), or combinations thereof.

5. The oral appliance of claim 1, wherein the ionically charged modifier comprises a cationic modifier.

6. The oral appliance of claim 5, wherein the cationic modifier comprises a cationic functional moiety of quaternary ammonium.

7. The oral appliance of claim 5, wherein the cationic modifier comprises bis(2- hydroxyethyl) dimethylammonium chloride (BHD AC).

8. The oral appliance of claim 1, wherein the ionically charged modifier comprises at least one anionic modifier and at least one cationic modifier.

9. The oral appliance of claim 1, wherein the ionic active agent comprises fluoride ions.

10. The oral appliance of claim 9, wherein the fluoride ions are obtained from sodium fluoride, stannous fluoride, or monofluorophosphate.

11. The oral appliance of claim 1, wherein the ionic active agent comprises an antimicrobial agent.

12. The oral appliance of claim 11, wherein the antimicrobial agent comprises chlorhexidine ions.

13. The oral appliance of claim 11, wherein the antimicrobial agent comprises cetylpyridinium ions.

14. The oral appliance of claim 1 , wherein the ionic active agent comprises one or more essential oils.

15. The oral appliance of claim 14, wherein the one or more essential oils comprise essential oils selected from eucalyptol, menthol, menthone, carvone, thymol, cinnamaldehyde, eugenol, and methyl salicylate.

16. The oral appliance of claim 1, wherein the ionic active agent comprises one or more flavors selected from spearmint, peppermint, and cinnamon.

17. The oral appliance of claim 1, wherein the ionic active agent is ionically bound to the ionically charged modifier by a solution imbibing technique wherein the oral appliance body is exposed to an imbibing solution comprising the ionic active agent dissolved in a solvent which is compatible with the polyurethane-based resin.

18. The oral appliance of claim 1, wherein the ionic active agent is ionically bound to the ionically charged modifier by a bulk mixing technique wherein polyurethane-based resin is mixed with the ionic active agent prior to forming the oral appliance body.

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