Compositions and methods for root canal sealants

Abstract

Disclosed herein is a composition comprising: a polyol moiety comprising a catalyst, a defoamer, and modified nanoparticles; and a diisocyanate moiety wherein the polyol moiety and the diisocyanate moiety are present in a molar ratio of 1: 1, and wherein the composition is an elastomeric polyurethane sealant.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 407,018, filed on September 15, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Some embodiments of the disclosure relate to compositions and methods for endodontic treatment, and more particularly to compositions for root canal filling and methods of use thereof. Background Art

[0004] Endodontic treatment or root canal therapy (RCT) is a commonly performed dental treatment in the dental field. Typically, RCT involves the treatment of the internal space of the tooth (which contains soft tissue called "pulp tissue") and then filling the internal space with a biocompatible material. After the pulp is removed from the root canal space, and after cleaning, shaping and / or irrigating the root canal space, the cleaned, disinfected and shaped root canal space is dried and then filled with a biocompatible material. Summary of the invention

[0005] Some embodiments disclosed herein relate to compositions and methods for synthesizing biocompatible polymer foam materials and methods for using polymer foam materials. Some embodiments of polymer foam materials include expandable polymers (including expandable biocompatible polymers), wherein their expansion characteristics are that they can be controlled to meet three dimensions of a specific application. Some embodiments of expandable biocompatible polymers can be applied to many dental applications, such as but not limited to fillers, sealants, fillers, root canal fillers and combinations thereof. Some embodiments of polymer foam materials can be placed in contact with, for example, but not limited to, dentin, enamel, etc. In some embodiments, polymer foam materials can be formed within different tissue conditions, pH, temperature and humidity levels, so that, for example, polymer foam materials have improved biocompatibility properties, which will not negatively affect the tissue conditions in contact or close to the polymer foam material. For example, some embodiments of polymer foam materials will not negatively affect the contact tissue conditions. Examples of negative effects on the contact tissue conditions include changing (i.e., significantly reducing or increasing) one or more properties of the tissue, wherein these properties include but are not limited to pH, temperature and humidity levels.

[0006] In some embodiments, the disclosure is directed to a composition comprising: a polyol portion comprising: a catalyst, a defoamer, and modified nanoparticles; wherein the composition is an elastomeric polyurethane sealant.

[0007] In some embodiments, the polyol portion includes hydroxyl terminated polybutadiene.

[0008] In some embodiments, the catalyst is pentamethylguanidine.

[0009] In some embodiments, the catalyst comprises 0.4 wt % to 0.6 wt % of the total composition.

[0010] In some embodiments, the antifoaming agent includes Antifoam A concentrate.

[0011] In some embodiments, the defoaming agent is a silicone defoaming agent configured to control the expansion of the composition.

[0012] In some embodiments, the antifoaming agent comprises 0.1 wt % to 0.3 wt % of the total composition.

[0013] In some embodiments, the modified nanoparticles include 5 wt % stearic acid.

[0014] In some embodiments, the modified nanoparticles include surface hydroxyl groups configured to react with diisocyanates.

[0015] In some embodiments, the composition further includes a diisocyanate moiety.

[0016] In some embodiments, the diisocyanate moiety includes L-lysine diisocyanate and a water scavenger.

[0017] In some embodiments, the polyol moieties and the diisocyanate moieties are present in a 1:1 molar ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1A is a schematic diagram of a root canal space in a tooth according to an embodiment of the disclosure.

[0019] Figure 1B is a top cross-sectional view of a root canal according to an embodiment of the disclosure, showing a complex and irregular root canal pattern.

[0020] Figure 2 is a schematic diagram of a filled / sealed root canal space according to an embodiment of the disclosure.

[0021] Figure 3A is a perspective view of a prototype of an EPS sealant according to an embodiment of the disclosure.

[0022] Figure 3B is a perspective view of an EPS pre-prototype according to an embodiment of the disclosure.

[0023] Figure 4is a box plot of the mean and standard deviation of the surface porosity of various sealants according to embodiments of the disclosure.

[0024] Figure 5A is a box plot of the mean and standard deviation of cell viability in MTS at 24 hours for various sealants according to embodiments of the disclosure.

[0025] Figure 5B is a box plot of the mean and standard deviation of cell viability in MTS at 48 hours for various sealants according to embodiments of the disclosure.

[0026] Figure 5C is a box plot of the mean and standard deviation of cell viability in MTS at 72 hours for various sealants according to embodiments of the disclosure.

[0027] Figure 5D is a box plot of the mean and standard deviation of cell viability in MTS at 96 hours for various sealants according to embodiments of the disclosure.

[0028] Figure 6 is the CNV surface area (μm) of various sealants according to embodiments of the disclosure 2 ) box plot of the mean and standard deviation.

[0029] Figure 7 is a box plot of the mean and standard deviation of penetration depth (μm) for various sealants according to embodiments of the disclosure.

[0030] Fig. 8A is a SEM micrograph showing the surface porosity of AH Plus according to an embodiment of the disclosure.

[0031] Figure 8B is a SEM micrograph showing the surface porosity of Sure Seal according to an embodiment of the disclosure.

[0032] Figure 8C is a SEM micrograph showing the surface porosity of a PES according to an embodiment of the disclosure.

[0033] Fig.8D is a SEM micrograph showing the surface porosity of EPS according to an embodiment of the disclosure.

[0034] Fig. 9A is a box plot of the mean and standard deviation of flow diameters for various sealants according to embodiments of the disclosure.

[0035] Fig. 9Bis a box plot of the mean and standard deviation of setting times for various sealants according to embodiments of the disclosure.

[0036] Fig. 9C is a box plot of the mean and standard deviation of the radiopacity of various sealants according to embodiments of the disclosure.

[0037] Fig.9D is a box plot of the mean and standard deviation of the flow surface areas of various sealants according to embodiments of the disclosure.

[0038] Fig.10 is a graph depicting in vitro weight loss of various sealants during a 16-week testing period using an accelerated aging model in accordance with embodiments of the disclosure.

[0039] Fig.11 is a schematic diagram of a multi-barrel syringe containing embodiments of a first fluid and a second fluid in respective barrels according to an embodiment of the disclosure.

[0040] Fig.12 is a flow chart of a process according to an embodiment of the disclosure for a process according to an embodiment. DETAILED DESCRIPTION

[0041] In addition to those benefits and improvements already disclosed, other objects and advantages of the disclosure will become apparent from the following description in conjunction with the accompanying drawings. Detailed embodiments of the disclosure are disclosed herein; however, it should be understood that the disclosed embodiments are merely illustrative of the disclosure that can be implemented in various forms. In addition, each example given with respect to various embodiments of the disclosure is intended to be illustrative and not restrictive.

[0042] Throughout the specification and claims, the following terms take the meanings clearly associated with this document unless the context clearly dictates otherwise. The phrases "in one embodiment," "in an embodiment," and "in some embodiments" as used herein do not necessarily refer to the same embodiment, although they may refer to the same embodiment. In addition, the phrases "in another embodiment" and "in some other embodiments" as used herein do not necessarily refer to different embodiments, although they may refer to different embodiments. All embodiments of the disclosure are intended to be combined without departing from the scope or spirit of the disclosure.

[0043] As used herein, the term "based on" is not exclusive and allows for being based on additional factors not described unless the context clearly dictates otherwise. In addition, throughout the specification, the meanings of "a", "an" and "the" include plural references. The meaning of "in" includes "in" and "on".

[0044] Figure 1A and Figure 1B An exemplary view of a tooth 10 according to one embodiment is shown, which has a complex and irregular pattern of root canal spaces 12. The root canal spaces 12 can have a very complex structure and irregular pattern, as they can include a main root canal 14 and a secondary root canal 16. Therefore, cleaning, disinfecting, and filling such an irregular pattern can cause difficulties.

[0045] In one embodiment, the filling material 18 includes at least one expandable material. The at least one expandable material of the filling material 18 may include at least one of the following: a swellable material, a foamable material, the like, or any combination thereof. In some embodiments, the expandable material of the filling material 18 may be a cross-linkable material that expands upon cross-linking. In some embodiments, the cross-linking may be performed in situ. In one embodiment, the filling material 18 is configured to expand so as to fill most, substantially all, or all of the main root canal 14 and the secondary root canal 16 of the root canal space 12. In one embodiment, the filling material 18 includes at least one biocompatible material. In one embodiment, the at least one biocompatible material is an expandable material.

[0046] Figure 2 A schematic diagram of an embodiment of a filled or closed root canal space 12 is shown showing the primary and secondary root canals 14 , 16 filled with a filling material 18 .

[0047] In some embodiments, the expandable material of the filling material 18 expands using isocyanate chemistry (i.e., a chemistry of a material that includes at least one isocyanate group). For example, in one embodiment, isocyanate chemistry can be utilized to induce cross-linking of the expandable material of the filling material 18. In one embodiment, isocyanate chemistry can be utilized to induce foaming of the expandable material of the filling material 18.

[0048] Materials including isocyanate groups may become unstable when exposed to various conditions, including, but not limited to, the presence of water, the presence of moisture, the presence of other compounds, etc. Thus, various conditions may cause the decomposition of the isocyanate groups, thereby crosslinking the one or more polymers to which the isocyanate groups are attached and releasing carbon dioxide (CO 2 )gas.

[0049]

[0050] In some embodiments, the released CO 2 In some embodiments, the CO 2 The generation or release of gases can control the formation of pores in biocompatible cross-linked polymers. 2The generation or release of the gas, its three-dimensional structure and its physical properties (e.g., compression and / or expansion properties) are also controlled to specific desired amounts. In addition, the CO exposure to nearby tissues is controlled. 2 The gas can beneficially minimize the effects of pH changes in the tissue.

[0051] For example, physiologically normal intracellular pH is most often between 7.0 and 7.4, but there are differences between tissues (e.g., mammalian skeletal muscle tends to have a pH of 6.8 to 7.1). Typically, dental infections have some infected tissue with an acidic pH. For example, the pH of pus from a periapical abscess of infected tissue can range between 6.0 and 7.3. Therefore, biocompatible materials that do not change the pH of surrounding tissues can be beneficial and advantageous. Embodiments of the biocompatible polymers disclosed herein can be configured (e.g., controlled) to release small amounts of CO 2 (eg, less than 7 wt %). Thus, embodiments of the biocompatible polymers and methods disclosed herein have numerous benefits and advantages over conventional materials and methods.

[0052] A non-limiting exemplary mechanism for cross-linking of materials containing isocyanate groups is shown below. The following non-limiting exemplary mechanism may be referred to as the "lysine model" of isocyanate cross-linking.

[0053]

[0054]

[0055] In one embodiment, the filler material 18 includes a plurality of swellable materials. In some embodiments, the plurality of swellable materials are configured to swell upon cross-linking. In one embodiment, the use of a plurality of swellable materials ensures that the filler material 18 is stable in water and saline.

[0056]

[0057] In one embodiment, the expandable material of the filling material 18 includes at least one condensation polymer. In one embodiment, the at least one condensation polymer includes polyglycerol-sebacate ("PGS"). In one embodiment, the at least one condensation polymer is formed by the condensation polymerization of glycerol and sebacic acid. A non-limiting exemplary synthetic pathway for forming PGS by condensation polymerization of glycerol and sebacic acid is as follows:

[0058] In one embodiment, the polymer of the expandable material of the filling material 18 includes at least one of the following: poly(lactic acid) (PLA), poly(glycolic acid) (PGA), at least one polymer from the polycaprolactone (PCL) class of polymers and copolymers thereof (e.g., poly(lactic acid-co-caprolactone) or poly(glycolic acid-caprolactone)), or any combination thereof. In one embodiment, copolymerization of at least one lactide, glycolide, or caprolactone monomer present in at least one polymer of the expandable material of the filling material 18 described herein in various ratios can produce materials having a wide range of mechanical properties, thermal properties, and degradation times. In one embodiment, the structure (and associated properties, such as molecular weight) of an exemplary PLA / PGA / PCL copolymer can be customized by adjusting, for example, the type of initiator used, the molar ratio of the initiator to at least one monomer unit, or any combination thereof.

[0059] According to an exemplary embodiment, a non-limiting synthetic pathway for poly(glycolide-co-caprolactone) (PGCL) is shown below. In the following non-limiting pathway, pentaerythritol is used as an initiator to form a 4-arm branched structure.

[0060]

[0061] In one embodiment, at least one polymer of the expandable material of the filling material 18 (or a compound of the polymer of the expandable material used to make the filling material 18) may include one or more pendant hydroxyl groups. In one embodiment, the hydroxyl group can be used as a site for attachment of a pendant group to at least one polymer, for example. In one embodiment, both glycerol and sebacic acid contain pendant hydroxyl groups that can be used to impart desired functional groups to PGS. In one embodiment, the filling material 18 may include at least one radiopaque material. In one embodiment, at least one radiopaque material may include at least one of the following: gold, platinum, tungsten, platinum-tungsten, palladium, iridium, platinum-iridium, rhodium, tantalum, barium sulfate, bismuth basic carbonate, bismuth oxychloride, bismuth trioxide, etc. (e.g., radiopaque metals, radiopaque alloys, or radiopaque ceramics) or any combination thereof.

[0062] In one embodiment, the filler material 18 may include at least one biostable material. In one embodiment, the at least one biostable material prevents the filler material 18 from being degraded by one or more endogenous enzymes. In a non-limiting exemplary embodiment, the biostable material includes at least one biostable metal oxide, such as, but not limited to, one or more of titanium oxide, ruthenium oxide, and iridium oxide.

[0063] In one embodiment, a porous polyurethane scaffold is synthesized when (PCLG) triol and isocyanate react, wherein CO 2 Acts as a foaming agent to form pores.

[0064] In one embodiment, the at least one expandable material of the fill material 18 comprises at least one polymer foam. In some embodiments, the polymer foam comprises a polymer material comprising a compound of formula [A]:

[0065]

[0066] According to one embodiment, a compound of formula [B] may be prepared and mixed with a compound of formula [C]:

[0067]

[0068] The mixing of compound [B] and compound [C] results in polymerization to form a compound of formula [A]. In one embodiment, the material including the compound of formula [A] has a molecular weight of 0.10 g / cm 3 Up to 0.40g / cm 3 density.

[0069] In some embodiments, the number of units "m" in the polymer comprising formula [A] is an integer in the range of 1 to 100 million.

[0070] In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 2 to 100 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 2 to 50 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 2 to 10 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 2 to 5 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 2 to 1 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 2 to 100,000. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 2 to 10,000. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 2 to 1000. In some embodiments, the number of monomer units "n" in the polymer comprising formula [A] is an integer in the range of 2 to 500. In some embodiments, the number of monomer units "n" in the polymer comprising formula [A] is an integer in the range of 2 to 100.

[0071] In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 100 to 100 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 100 to 100 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 10,000 to 100 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 100,000 to 100 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 1 million to 100 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 10 million to 100 million. In some embodiments, the number of monomer units "n" in a polymer comprising formula [A] is an integer in the range of 50 million to 100 million.

[0072] Go to Figure 3A and Figure 3B , discloses sealants according to embodiments of the disclosure. In some embodiments, the sealant is a polymer sealant. In some embodiments, the sealant is an elastomeric polyurethane sealant (EPS). Figure 3A A prototype EPS sealant according to an embodiment of the disclosure is depicted. Figure 3B EPS pre-prototypes according to embodiments of the disclosure are depicted. In some embodiments, the EPS formulation includes a polyol portion, which includes a catalyst, a defoamer, and modified nanoparticles. In some embodiments, the EPS formulation includes a diisocyanate portion. In some embodiments, the polyol portion includes a hydroxyl-terminated polybutadiene (HTPB). In some embodiments, the catalyst is 0.5% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.3% by weight to 0.7% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.35% by weight to 0.7% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.4% by weight to 0.7% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.45% by weight to 0.7% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.5% by weight to 0.7% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.55% by weight to 0.7% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.6% by weight to 0.7% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.65 wt % to 0.7 wt % pentamethylguanidine.

[0073] In some embodiments, the catalyst is 0.3% to 0.65% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.3% to 0.6% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.3% to 0.55% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.3% to 0.5% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.3% to 0.45% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.3% to 0.4% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.3% to 0.35% by weight of pentamethylguanidine.

[0074] In some embodiments, the catalyst is 0.4% to 0.6% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.45% to 0.55% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.5% to 0.65% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.35% to 0.45% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.4% to 0.5% by weight of pentamethylguanidine. In some embodiments, the catalyst is 0.4% to 0.65% by weight of pentamethylguanidine.

[0075] In some embodiments, the defoamer is a defoaming concentrate. In some embodiments, the defoamer is a 100% active silicone polymer. In some embodiments, the defoamer is present at 0.2% by weight. In some embodiments, the defoamer is 0.1% to 0.3% by weight of a defoaming concentrate. In some embodiments, the defoamer is 0.15% to 0.3% by weight of a defoaming concentrate. In some embodiments, the defoamer is 0.2% to 0.3% by weight of a defoaming concentrate. In some embodiments, the defoamer is 0.25% to 0.3% by weight of a defoaming concentrate.

[0076] In some embodiments, the defoamer is 0.1% to 0.25% by weight of defoamer concentrate. In some embodiments, the defoamer is 0.1% to 0.2% by weight of defoamer concentrate. In some embodiments, the defoamer is 0.1% to 0.15% by weight of defoamer concentrate.

[0077] In some embodiments, the modified nanoparticles include 5 wt% stearic acid to improve their dispersion and adhesion between the filler and the polymer matrix. In some embodiments, the diisocyanate portion includes L-lysine diisocyanate (LDI) and a water scavenger. In some embodiments, the polymer sealant is prepared by mixing the polyol portion and the diisocyanate portion based on a 1:1 molar ratio of diisocyanate and HTPB.

[0078] In some embodiments, EPS formulations are able to control the amount of foaming by improving the hydrophobicity of the material via HTPB, thereby reducing the diffusion of water into the dentinal tubules and the subsequent release of CO2. In addition to controlling the amount of expansion, HTPB has a structure that is compatible with gutta-percha, thereby preventing any phase separation in the structures of these two compounds and indicating the possibility of using EPS formulations in combination with other filling materials. In some embodiments, surface modification of essential fillers by EPS formulations will ensure proper distribution of the fillers to reduce water absorption and prevent their agglomeration. In addition, unmodified nanoparticles contain surface hydroxyl groups that can react with diisocyanates in a polymerization reaction, as demonstrated in the first formulation below.

[0079]

[0080] Example 1

[0081] Tests were performed to evaluate the biocompatibility, porosity, and permeability of our newly developed swellable sealants. Sealants AH Plus, Sure Seal, polyurethane swellable sealant (PES), and EPS were tested for cytotoxicity according to ISO 10993-5. MTT assays showed that both EPS formulations were significantly less cytotoxic at all time intervals, likely due to the release of less toxic byproducts compared to the other tested sealants.

[0082] The second model utilized in this study was a laser-induced mouse CNV model. The total area of ​​CNV associated with each point hit by the laser on the mouse was measured using ImageJ software (in μm2). The results of the CNV assay showed that both EPS formulations were more pro-angiogenic than the other tested sealants, which may be beneficial for apical tissue regeneration.

[0083] Furthermore, the results showed that the penetration depth of EPS was significantly higher than that of AH Plus and Sure Seal. The deeper penetration may be due not only to the lower film thickness, viscosity, and surface tension of EPS, but also to the superior swelling of EPS due to the generation of CO2, which pushes the sealant into the dentinal tubules. SEM micrographs showed that the surface porosity of AH Plus, Sure Seal, and PES was significantly higher compared to EPS.

[0084] In the next set of tests, the sealants AH Plus, EndoSequence BC as well as PES and EPS were evaluated in terms of flowability, radiopacity and setting time according to ISO 6876:2012. The results showed that the largest surface area and flow diameter were detected in EPS, which allows the filling material to penetrate significantly more of the dentinal tubules and irregularities of the root canal space than the other tested sealants. The shorter setting time of EPS can be explained by the rapid reaction of these sealants, which is more accelerated for the newly developed formulations. It can be assumed that by increasing the expansion rate, the setting time is reduced. In addition, the reduced radiopacity of PES compared to AH Plus can be explained by the differences in the ratio of radiopaque agents and / or nanoform zirconium oxide used in the PES composition.

[0085] Cytotoxicity testing was also performed according to ISO 10993-5. The results showed that the EPS formulation was more pro-angiogenic than the other tested sealants, which may be beneficial for apical tissue regeneration.

[0086] Testing was also performed on improved polymer radiopacity and catalyst ratios in the filler ingredients of EPS formulations, including nano zinc oxide, nano zirconium oxide particles, and nano calcium tungstate. The results showed that the EPS formulation had higher radiopacity than EndoSequenceBC and PES.

[0087] Figure 4 Box plots depicting the mean and standard deviation of the surface porosity of various sealants.

[0088] FIG. 5A to FIG. 5D Box plots depicting the mean and standard deviation of cell viability in MTS for various sealants at the following times: 24 h ( Figure 5A )、48 hours( Figure 5B )、72 hours( Figure 5C ) and 96 hours ( Figure 5D ).

[0089] Figure 6 The CNV surface area (μm) of various sealants is plotted. 2 ) box plot of the mean and standard deviation.

[0090] Figure 7 Box plots depicting the mean and standard deviation of the penetration depth (μm) for various sealants.

[0091] FIG. 8A to FIG. 8D Depicted are SEM micrographs showing surface porosity at the gutta-percha and root canal dentin interface. Fig. 8A Depicted is the porosity visible in AH Plus. Figure 8BDepicts visible gaps in Sure Seal due to shrinkage. Figure 8C Depicted is the visible porosity of PES due to polyethylene glycol. Fig.8D The EPS is depicted to have no visible porosity due to HTPB.

[0092] 9A to 9D Box plots depicting the means and standard deviations for the experimental sealant groups. Specifically, Fig. 9A The flow diameters (mm) of various sealants are depicted; Fig. 9B The setting time (min) of various sealants is depicted; Fig. 9C The radiopacity (mm Al) of various sealants is depicted; Fig.9D Plotting the flow surface area (mm) of various sealants 2 ).

[0093] Fig.10 The in vitro weight loss of various sealants during a 16-week test period using an accelerated aging model is depicted. EPS formulations according to embodiments of the disclosure were found to be significantly more stable than all other sealants. Gutta-percha was used as a control.

[0094] Exemplary Method of Use 1: In an exemplary non-limiting embodiment, the filling material 18 can be prepared in a dental operating room environment by the following steps:

[0095] 1. Add the hardener to the isocyanate in a sterile tank.

[0096] 2. Insert the can into the fixture loading tray.

[0097] 3. Lower the impeller to the preset mixing height in the tank.

[0098] 4. Mix the isocyanate and hardener mixture in a can at about 11,000 RPM for about 40 seconds.

[0099] 5. Remove the spindle from the can.

[0100] 6. Remove the cans from the loading tray.

[0101] 7. Inject the polyurethane into the mixed isocyanate and hardener mixture.

[0102] Exemplary Method of Use 2: In another exemplary non-limiting embodiment, the filling material 18 can be prepared in a dental operating room environment by the following steps:

[0103] 1. Add the hardener to the isocyanate in a sterile tank.

[0104] 2. Insert the can into the fixture loading tray.

[0105] 3. Lower the impeller to the preset mixing height in the tank.

[0106] 4. Mix the isocyanate and hardener mixture in a tank at 10,000 RPM to 12,000 RPM for 30 seconds to 50 seconds. For example, mix the isocyanate and hardener mixture in a tank at 11,000 RPM for 40 seconds.

[0107] 5. Remove the spindle from the can.

[0108] 6. Remove the cans from the loading tray.

[0109] 7. Inject the biopolymer into the isocyanate and hardener mixture.

[0110] In one embodiment, the resulting mixture produces biopolymers with medium or low levels of porosity and biocompatibility that can be used as a root filling material 18 .

[0111] Fig.11 A non-limiting exemplary embodiment of a multi-barrel syringe 30 (eg, a dual-barrel syringe) is shown that includes a first barrel chamber 32 containing a first fluid 34 and a second barrel chamber 36 containing a second fluid 38 .

[0112] In one embodiment, the first fluid 34 comprises a compound according to formula [B] above, and the second fluid 38 comprises a compound according to formula [C] above.

[0113] In another embodiment, the first fluid 34 comprises a prepolymer according to formula [D] above, and the second fluid 38 comprises a cross-linking agent (ie, chain extension catalyst), for example, glycerol.

[0114] When the plunger 40 of the multi-barrel syringe 30 is depressed, pressure forces the first fluid 34 and the second fluid 38 to flow downstream. At or near the tip 42 of the multi-barrel syringe 30, the first fluid 34 and the second fluid 38 mix together.

[0115] According to one embodiment, the first fluid 34 and the second fluid 38 are mixed together outside of the multi-barrel syringe 30 .

[0116] According to one embodiment, the first fluid 34 and the second fluid 38 are mixed together downstream of the first barrel chamber 32 and the second barrel chamber 36 of the multi-barrel syringe 30 .

[0117] According to one embodiment, the first liquid 34 and the second liquid 38 are not mixed together outside of the multi-barrel syringe 30 .

[0118] According to one embodiment, the tip 42 is a mixing tip 42 , which may or may not be a separable component, and the first fluid 34 and the second fluid 38 mix together as they flow through the mixing tip 42 .

[0119] Fig.12 A non-limiting exemplary embodiment of a method 50 for producing an expandable biocompatible polymer material is shown. In a first step 52, at least one polymer is obtained, wherein the at least one polymer comprises at least one monomer unit or prepolymer, such as one or more selected from the group consisting of at least one lactide unit, at least one glycolide unit, at least one caprolactone unit, or any combination thereof. In a second step 54, at least one compound comprising at least one isocyanate group is obtained.

[0120] According to one embodiment, in the first step 52, the monomer unit is a compound of formula [B], and in the second step 54, the compound comprises a compound of formula [C].

[0121] According to one embodiment, in a first step 52, the prepolymer is a compound of formula [D], and in a second step 54, the compound includes a crosslinking agent (i.e., a chain extension catalyst), such as glycerol. In a next step 56, at least one polymer is mixed with at least one compound including at least one isocyanate group so that they react to form a biocompatible polymer material. The biocompatible polymer material can be used to fill at least a portion of a cavity or empty space, such as a tooth or a root canal.

[0122] In some embodiments of the method for making a polymeric material, the method does not include the use of a surfactant. That is, the process of making a polymeric material does not require any surfactant. Examples of surfactants include, but are not necessarily limited to, one or more of the following: silanes, sodium lauryl sulfate (SLS), cocamidopropyl betaine (tego betain) and sodium methyl cocoyl taurate (adinol). In some embodiments of the method for making a polymeric material, the method does not include the use of an additive binder. That is, the process of making a polymeric material does not require any additive binder. Examples of binders include, but are not necessarily limited to, one or more of the following: adhesives, epoxy resins, resins, or acetone. In some embodiments of the method for making a polymeric material, the method does not include the use of both a surfactant and a binder.

[0123] Although several embodiments of the disclosure have been described, it should be understood that these embodiments are merely illustrative and non-restrictive, and that many modifications may become apparent to those of ordinary skill in the art. In addition, the various steps may be performed in any desired order (and any desired steps may be added and / or any desired steps may be eliminated).

[0124] The following aspects are provided as exemplary embodiments of the disclosure.

[0125] Aspect 1. A composition comprising:

[0126] Polyol part, the polyol part includes:

[0127] catalyst,

[0128] Defoamers, and

[0129] Modified nanoparticles;

[0130] Wherein the composition is an elastomeric polyurethane sealant.

[0131] Aspect 2. The composition according to aspect 1, wherein the polyol portion comprises a hydroxyl-terminated polybutadiene.

[0132] Aspect 3. The composition according to aspect 1, wherein the catalyst is pentamethylguanidine.

[0133] Aspect 4. The composition according to aspect 1, wherein the catalyst accounts for 0.4 wt% to 0.6 wt% of the total composition.

[0134] Aspect 5. The composition according to aspect 1, wherein the defoaming agent comprises defoaming concentrate.

[0135] Aspect 6. The composition according to aspect 1, wherein the defoaming agent is a silicone defoaming agent configured to control expansion of the composition.

[0136] Aspect 7. The composition according to aspect 1, wherein the defoaming agent accounts for 0.1 wt % to 0.3 wt % of the total composition.

[0137] Aspect 8. The composition according to aspect 1, wherein the modified nanoparticles comprise 5 wt% stearic acid.

[0138] Aspect 9. The composition according to aspect 1, wherein the modified nanoparticles comprise surface hydroxyl groups configured to react with diisocyanate.

[0139] Aspect 10. The composition according to aspect 1, further comprising a diisocyanate portion.

[0140] Aspect 11. The composition according to aspect 10, wherein the diisocyanate portion comprises L-lysine diisocyanate and a water scavenger.

[0141] Aspect 12. The composition according to aspect 10, wherein the polyol moiety and the diisocyanate moiety are present in a molar ratio of 1:1.

Claims

1. A composition, include: A polyol portion, the polyol portion comprising: catalyst, Defoamers, and Modified nanoparticles; The composition is an elastomeric polyurethane sealant.

2. The composition of claim 1, wherein the polyol moiety comprises hydroxyl terminated polybutadiene.

3. The composition of claim 1, wherein the catalyst is pentamethylguanidine.

4. The composition of claim 1, wherein the catalyst comprises 0.4 to 0.6 weight percent of the total composition.

5. The composition of claim 1, wherein the defoaming agent comprises defoaming concentrate.

6. The composition of claim 1, wherein the defoamer is a silicone defoamer configured to control expansion of the composition.

7. The composition of claim 1, wherein the defoaming agent comprises 0.1 wt% to 0.3 wt% of the total composition.

8. The composition of claim 1, wherein the modified nanoparticles comprise 5 wt% stearic acid.

9. The composition of claim 1, wherein the modified nanoparticles include surface hydroxyl groups configured to react with diisocyanates.

10. The composition of claim 1 further comprising a diisocyanate moiety.

11. The composition of claim 10, wherein the diisocyanate moiety comprises L-lysine diisocyanate and a water scavenger.

12. The composition of claim 10, wherein the polyol moiety and the diisocyanate moiety are present in a molar ratio of 1:1.

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