JPH0818946B2 - Composite denture with soft liner - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION Removable prosthetic dentures typically consist of a hardened poly (methyl methacrylate) substrate that supports the artificial teeth needed for chewing and dental cosmetics. Many patients have difficulty tolerating hard dentures, and therefore a need for a soft liner attached to a soft tissue cushioning denture base. Numerous criteria have been established for denture liners, materials useful as nominally non-toxic and non-allergenic liners.

[0002]

BACKGROUND OF THE INVENTION Several liner materials have been proposed that meet more than enough criteria to be useful.
For example, silicone rubber, plasticized poly (methacrylate) s, polyurethanes and polyvinyl chloride. A particularly useful liner material is U.S. Patent No. 4,251,215 (1981).
Issued on May 17, 2000 to May et al.). It is a phosphonitrile fluoroelastomer (poly (fluoroalkoxy) phosphazene) which has particularly good resilience and biocompatibility properties.
However, it has been found that the fluoroelastomer liner materials illustrated herein have some drawbacks compared to their theoretical ideal values for tensile strength, hardness, water absorbency, and bond strength to denture base materials. .

In addition, the method of denture formation described in the Mei et al. Patent is a two-step process, in which the liner and denture base must be cured separately and, in addition, due to the use of a strong binder and liner curing. 100 ° C (boiling point of water under atmospheric pressure)
It is necessary to use the above temperature. The production of this conventional composite denture requires precision equipment and cannot be conveniently done in an average dentist's or laboratory.

In order to overcome the disadvantages of such prior art compositions, US Pat. No. 4,432,730 ( Jettlmann et al.
A liner composition of the type described in Application October 1, 1982, incorporated herein by reference) has been proposed. While such dental liner compositions have generally proven satisfactory, the cured liner material according to the Jettlman et al. Patent has a higher water absorption (4-5% than that desired for optimal oral use). w / w).

This composition also has methyl methacrylate (M
MA) monomer, which is volatile and therefore difficult to control prior to curing, and the hardness and water absorbency of these prior art compositions is highly dependent on the appropriate amount of MMA. Was found. Therefore, it is desirable to reduce the water absorption properties and associated swelling properties of this prior art dental liner material in order to improve the dimensional stability of the product liner material over time.

[0006]

The best materials are permanently elastic, inert, cleanable and essentially water insoluble, with low water absorption properties and good tensile strength. It has a bond strength. Softness is desirable for comfort, but the liner material must be sufficiently stiff to replace the soft tissue of the mouth. And
It should therefore be possible to brush around the denture without the formation of ulcer spots on the tissue and, moreover, the liner material should be able to permanently bond to the denture base material. From a practical point of view, lined dentures can be made under conditions that are commonly found in dental laboratories or in the dentist's office, without extreme temperature, pressure conditions or the use of special equipment. It is suitable.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a composite denture containing an improved denture liner based on phosphonitrile fluoroelastomers (poly (fluoroalkoxy) phosphazenes), which has side chain groups. When cured by cross-linking, it retains the excellent elastic properties of the fluoroelastomer base material, while having improved water absorption properties, hardness, tensile strength, crushing and conditioning ability and bond strength. The denture liner composition is
It can be cured at a temperature of 100 ° C. or lower under atmospheric pressure.

A composite denture is preferably formed by curing the formed liner material itself, ie, a denture that is installed or present relative to a conventional denture base dough that can be partially cured. It is supposed to be relined. The filled denture flask is preferably immersed in an open bath at a temperature suitable for curing the denture base and liner, at a temperature of 100 ° C. or less, for curing the liner and the denture base together. This method improves the bond strength of the finished composite denture and eliminates the use of potentially harmful binders such as sulfuric acid or perfluoroacetic acid or epoxy or urethane adhesives.

Most importantly, it does not use high temperature and / or pressurized equipment, which is why
It can also be used in a commercial dental laboratory or dentist room. Also, the use of relatively low temperatures avoids evaporation of volatile monomers present and prevents dehydration of the liner material during curing. Evaporation creates micropores in the denture base and liner, and dehydration requires rehydration of the whole denture prior to use in the intended aqueous environment.
And, the dehydration / rehydration step causes undesired dimensional changes in the liner and in the substrate denture base.

Broadly, the denture liner composition of the present invention comprises a phosphonitrile fluoroelastomer in combination with at least one di- and trimethacrylate crosslinker, which improves the hardness of the cured product liner and its water absorbency. It will decrease. These components have the function of providing an internal penetrating polymer network, which improves tensile strength and reduces water absorption properties without adversely affecting hardness.

Suitable bifunctional agents include dimethacrylate glycol ester crosslinkers, especially polyethylene glycol dimethacrylate (PEGDMA), 1,6-hexamethylene glycol dimethacrylate, which improves the tensile and bond strength of the product liner. (HGDMA), ethylene glycol dimethacrylate (EGDMA), or tetraethylene glycol dimethacrylate (TEGDM)
A); and, in particular, EGDMA increases hardness and improves the processability and filling properties of uncured liners.

Trimethylpropane trimethacrylate
(TMP-TMA) is a particularly effective trifunctional crosslinker. Hard acrylic resin, silica, Al ₂ O ₃ is diatomaceous earth or BaSO ₄
It is desirable to also include fillers, such as particles of, to increase hardness, improve dough filling capacity, hardened liner polishing and conditioning properties, and in the case of BaSO ₄ , improve radiopacity. Is. Further, the composition optionally includes additives to facilitate curing of the liner material by the growth of an internal permeable network of acrylic moieties, the acrylic moieties at 100 ° C. or less,
It is cross-linked with suitable polyphosphazine chains and in particular contains benzoyl peroxide or lauroyl peroxide as free radical initiators. Lauroyl peroxide is particularly useful because it helps to plasticize the elastomer in particular.

The following materials are within the scope of the invention as a mixture. Material % by weight of total composition Useful range Suitable range Phosphonitrile 30-60 Fluoroelastomer 30-90 40-90 Trimethacrylate) 5-20 18-20 Crosslinker) Internal penetrating dimethacrylate) Network 0.5-20 2-4 ( EGDMA) Crosslinking agent) Filler 0-15 10-12 Initiator 0.5-1.0 1.0 (Lauroyl peroxide) Pigment 0-0.5 0.1-0.2 (CdSSe)

When using TMP-TMA and EGDMA, 40:
A TMP-TMA / EGDMA ratio of 1 to 1: 4 is generally suitable.
A ratio of about 10: 1 to 9: 2 is preferred, but increasing EGDMA relative to TMP-TMA increases water absorption. A TMP-TMA / EGDMA ratio of about 9: 2 is generally preferred.
It is contemplated to use other di- and tri-functional methacrylates with comparable trimethacrylate / dimethacrylate ratios.

When applied to a conventional denture base dough, typically acrylic dough, fresh filled or partially acrylic dough such as poly (methylmethacrylate), it can cure on its own, thus The base and liner are cured together. The liner can cure on its own on a cured base and is typically desirable when relining a preexisting denture. In both cases, when the denture base is first wet with a C ₁ -C ₆ alkyl monomethacrylate, especially methyl methacrylate (MMA), the adhesion between the liner and the base is usually promoted.

The dental liner composition of the present invention is based on phosphonitrile fluoroelastomers (poly (fluoroalkoxy) phosphazenes) of the type described in Rose et al., US Pat. Nos. 3,702,833 and 3,888,799.

The polymer has the general formula:

Embedded image (Where X is H or F; n is usually 1 to 11).

Such elastomers are commercially available and are compounded PNF-200, which is conventionally available from Firestone Central Research Laboratories (Firestone Parkway 1200, Arcron, Ohio), and Ethyl Corporation (Baton Rouge, LA). From Apel-F.

This material is

Embedded image (However, n is 3, 5, 7, 9 or 11 and m is 1
50,000-50,000) and described as thermosetting.

Commercially available compounded product, PNF-200
(Firestone) is reported to have the following properties:

Color amber Specific gravity 1.75 to 1.85 Mooney viscosity 15 Solvent ketones, THF, DMF Glass transition temperature -68 ° C (90 ^° F) Durometer A hardness 35 to 90 Tensile strength 6.9 to 13.8 MPa (1000 to 2000lbf / in ² ) 100% modulus 2.8-13.8MPa (200-2000lbf / in ² ) Elongation 75-250% Tear resistance 43,800N / m (250 lbg / in)

The fluoroelastomer is preferably purified in a known manner by extraction from acetone and condensation before use of the biological medium in the liner composition according to the invention. The elastomer comprises about 30% by weight of the total denture liner composition.
It is used in an amount of about 90% by weight, usually about 30-60% by weight for hard liner materials and about 40% -90% for soft liner materials.

PNF-200, commercially available from the manufacturer Firestone, has a residual amount of NaCl, nominally about 0.05%.
It is noted that it contains less than w / w. The presence of NaCl adversely affects the water absorption properties of compounded elastomers, and it is therefore important that the elastomer be purified from this contamination.

[0024] This is the raw gum is reagent grade acetone (5%
w / w), then filter the powder contaminants, then
It is easily done by precipitating in deionized water with the squeezing degree of a rubber card. The card is then dried in vacuum to constant weight. Thereby, or with a similar treatment method, the water absorption properties of the raw gum are significantly improved. Further, the swelling of the fully polymerized liner material caused by water absorption during use or storage can be substantially reduced by storing the cured product in a 10% KCl solution or other similar salt solution, or It can be lost.

In accordance with the present invention, the fluoroelastomer is both a di- and tri-functional methacrylate, such as TMP-TMA, PEGDMA, HGDMA, TEGDMA, or EGDM.
It is preferably cured in the presence of a cross-linking agent containing A,
It reduces water absorption, improves bond strength and tensile strength, and provides sufficient hardness and elongation of the liner material when bonded to a denture base. The cross-linking agent is a fluoroelastomer,
It is included in an amount of about 5.5% to 25% by weight of the bifunctional and trifunctional crosslinker based on the weight of the total composition, preferably about 20% to 24% by weight.

In one embodiment of the invention, the liner is
Dimethacrylate glycol ester, preferably
With ethylene glycol dimethacrylate (EGDMA), compounded in TMP-TMA and fluoroelastomers to improve the hardness, tensile strength, bond strength of liner products, and to improve processability and filling properties .

Generally speaking, the dimethacrylate crosslinker is from about 0.5% to about 20%, based on the total composition weight, based on the amount at the lowest end of the soft product and the highest end of the tough product.
%, Preferably about 2% to about 4% (EGDMA). The effect on water absorption of fluoroelastomers obtained with a range of methacrylate crosslinkers, obtained by stoichiometric adjustment to the point of attachment, is shown in Table 1. Water absorption properties were significantly improved by TMP-TMA.

[0028]

[Table 1] Water absorbency% After 7 days (%) After 14 days (%) Crosslinking agent (% is percentage by weight of composition) EGDMA 8 2.19 (w / w%) 2.36 EGDMA 13 2.88 3.32 HGDMA 8 3.61 4.30 HGDMA 13 3.83 4.62 TMP-TMA 4 4.25 5.19 TMP-TMA 8 3.07 3.54 TMP-TMA 13 2.25 2.63 TMP-TMA 18 1.48 1.60

The trifunctional cross-linking agent reduced the water absorbency, increased the hardness and the tensile strength of the fan. EGDMA
Only seems to have the opposite effect on water absorption properties, but EG
Dimethacrylates, like DMA, improve processability and packing properties, and increase the strength of the compositions of the invention. A balance must be struck between improving the mechanical strength of this liner material and maintaining its proper softness.

In addition, the liner composition of the present invention may also contain fillers that are uniformly admixed with the purified fluoroelastomer gum and di- and tri-functional crosslinkers. This filler is first suitable for ball milling with other powder components and then the powder mixture is processed on a rubber mill into a fluoroelastomer. The fluoroelastomer and powder components are then compounded into a di- and tri-functional crosslinker for a smooth, coagulation-free consistency. The initiator is then added as a solution dissolved in acetone. Thereafter, the material is stored in a sealed container, preferably in a cool place, such as in a refrigerator. Alternatively, the solid and liquid additives are ball milled to homogeneity and the milled additive is incorporated into the fluoroelastomer gum.

In the composition of the present invention, the fill powder significantly enhances the bond strength between the liner and the base, which is due to the stiffening of the rubber during curing as well as the mechanical liner and base material of these powders. This is due to the interlock. And the filler further improves the processability of the composition.

Suitably the powder comprises beads or fibers, it is generally preferred that the powder is compatible with the denture base dough and promotes adhesion during the curing process. LUCITONE 199 beads or fibers obtained from LDCaulk Company (a spin-off of Dentspray International, Inc.) (Milford, Del.) Are exemplary acrylic particles useful in the compositions of the present invention. These particles are hard grafted poly (methyl)
Methacrylate) resin and, for example,
LUCTITONE 199 Denture Base, similarly obtained, grafted
It is particularly useful for bonding with acrylic denture base dough, such as impact resistant poly (methylmethacrylate) thermoset.

Other fillers or extenders that may be included are:
There is a very small size of hydrophilic amorphous silica. These materials reduce the amount of fluoroelastomer required, increase hardness, and polish the cured elastomer,
Improves the polishing ability and, thus, the bond strength. Two examples of these fused silica fillers / fillers are QUSO WR
-542 (Peak Corp, Valley, PA) Silica washed with silicone oil, and TULLANOX 5
00 (Talco, No. Billerica, Mass.), Silica coated with trimethylchlorosilane. A particularly useful filler material is particles of barium sulphate, which can be made into a radiopaque dental liner that allows radiographic examination when fragments are swallowed, inhaled or lost in the patient's soft tissue in the event of trauma. It can be detected.

The amount of filler material used in the liner composition will vary according to the desired hardness of the finished liner material, which is described in the above-referenced US Pat. No. 4,432,730. Large amounts of poly (methylmethacrylate) particles (up to 28% by weight of the composition) were found resulting in reduced elongation, but the amount of filler was about 10% by weight of the composition.
With the above, there is no effect on the bonding strength or tensile strength,
On the other hand, it has the effect of increasing the firmness of the finished product in proportion. Thus, useful amounts of polymeric fibers are from about 0% by weight of the composition for a soft product to about 15% by weight of the composition for a hard product. Preferably, about 0% to about 10% by weight of the inorganic filler is used for soft products and about 10-12% by weight for hard products, depending on which filler material is used. are doing.

In addition to the trimethacrylate crosslinker, other ingredients commonly included in dental liners can also be compounded with the fluoroelastomer base. In particular, pigments that make the liner more visible, organic pigments, iron oxide pigments and Cd-S-S
e Pigments such as can be used.

The uncured liner of the present invention is a thermosetting putty-like material that is slightly tacky and moderately elastic. It can be easily pressed with finger pressure, and when cast in a standard dental flask at an initial pressure of 20.7 MPa or 3000 lbf / in ² , it has good flowability and good workmanship. At room temperature above 115 ^° F, the composition has a relatively short shelf life (2-4 days). However, when refrigerated at 2-7 ° C (34-45 ^° F), the shelf life is calculated to be unlimited. Short exposure of non-vulcanized (non-vulcanized) compositions to air or atmospheric moisture has no significant detrimental effect. Excess material can be recovered from the trial fill and stored again in a sealed container, refrigerated and set aside for subsequent use.

Generally, the curing treatment is carried out in an open water tank for 8 hours at 74 ° C. (165 ^° F.) or 1.5 hours at 74 ° C. (165 ° F.).
^o F) for an additional 0.5 hours at 100 ° C (2
When carried out at 12 ^° F., an elastomeric material with excellent dimensional stability is obtained. Soaking the cured elastomer in deionized water for a long time will result in some water uptake, but only a slight dimensional change. Selected samples stored in deionized water absorb 1-3% (w / w) water, then 10% KC
Storage in solution reduces to less than 1%. The cured composition absorbs little water, but has no appreciable swelling when stored in 10% KCl.

After curing, the liner can be surface-modified using a high speed rough cutting wheel. The pumice on the rag wheel can then be carefully used to polish. Its glass transition temperature is so low that even if the material is cooled,
It does not affect the polishing characteristics. It should be operated like any other rubber / substrate bond material and should be abraded from the rubber material to a rigid denture base. It has excellent stain resistance, and most stains can be removed by washing with soap and water and light rubbing with a soft, rigid brush.

The composite denture of the present invention comprises a fluoroelastomer blended with the components of a dental liner composition as described above, the resulting composition is pressure molded into a wafer, and after removal of the spacer, filled into a conventional gypsum mold flask. Widely formed by casting into the prepared denture base dough. This composite denture is then heat treated to cure the liner and denture base together to obtain a lined denture. In an exemplary process, denture waxing is boiled out of a conventional form of gypsum flask and filled with fresh denture base dough. A 1 to 3 mm silicone rubber spacer is placed on the tissue side of the mold space, a polyethylene sheet separator is placed, and a denture base dough is produced without over-extension or over-extension. Pre-cure at 74 ° C. (165 ^° F.) for 30-45 minutes can be done to stiffen the denture base so that soft liner filling can result in denture base material after flask cooling and after removal of the spacer. Does not replace

The methyl methacrylate monomer is then brushed onto the denture base and the entire surface is wetted to help ensure that the liner is bonded to the base. A sheet of PNF soft liner composition (usually 10-15 g) is cut into shapes, then placed against the base material and the flask again subjected to several trial fills against a thin polyethylene sheet separator. Next, press the denture flask under pressure without a separator (about 2
Seal at 0.7 MPa or 3000 psi. And heat treat the composite denture to completely cure the base and liner materials. This is done, for example, by placing the flask in an open water bath (at atmospheric pressure), first treating at 74 ° C (165 ^° F) for 1.5 hours, then at 100 ° C (212 ^° F) for about 0.5. Up to an hour or by treatment at 74 ° C (165 ^° F) for 8 hours. The soft denture liner cures through a free-radical initiator from the addition polymerization of peroxide and acrylate crosslinker, which penetrates internally and binds to a few active side groups present as side groups on the PNF molecule. .

In one advantage of the present invention, a wafer of hard liner material is placed entirely on the base material dough,
Trial fill, and the central portion of the liner on the alveolar ridge is shaped and cut. The soft liner material is then placed over the cut midsection and the flask retried and filled. Next, the composite denture is heat-cured. In this example, it is tight around the denture,
It provides a creep-resistant, high-strength material that is adjustable, abradable, and appropriately replaces the underlying soft tissue, while providing a soft cushion in the center of the denture on the jawbone structure. It provides a soft, deformable, low strength material that forms.

Another advantageous embodiment of the present invention is pre-curing in the same manner as outlined above to re-line a pre-existing denture and to provide its tissue-facing surface with a long-lived soft surface. Renewing with a denture liner extends the life of old dentures.

[0043]

EXAMPLES Manufacture of Permanently Soft Denture Liner Formulations Typically, liner composition badges are manufactured on a 6 inch roll mill in 25 to 100 gram lots. The next treatment was based on a 73.1 g badge. Compound Name Function phr grams manufacturing badges company number purified polyphosphazene PNF-200 100 50 fire Stone RPP- fluoroelastomer (Firestone) 13750 lauroyl initiator 1 0.5 Polysciences - - - - peroxide (Polysciences) BaSO ₄ Radiation 15 7.5 Baker ( Baker) 117160 Impervious filler 1030-1 Trimethylol crosslinker 18 9 Saltomer 310-713 Propane (Sartomer) Trimethacrylate ethylene glycol Crosslinker 2 1 Polyscience 2303 Dimethacrylate (Polysciences) Poly (methyl LUCITONE 10 5 Dentospray 102183 Methacrylate 199 (PMMA International Butadiene Beads) (Dentsply Styrene International) CdSSe Dark Red Pigment 0.2 0.1 Ferro Colors CP-1880 (Ferro Colors)

The powdered BaSO ₄ and PMMA are combined and ball milled together for several hours. These solids are then added to PNF gum on a cold roll mill and cut completely in and in the blend. Next, TMP-TMA, EGDMA, and these components are added to this, and it rolls carefully and it becomes uniform. When the above is mixed to a smooth, lump-free consistency, peroxide is added as a solution in solution in reagent grade acetone (0.5 g peroxide in 5-10 ml acetone is typical). Further acetone can be added for homogenization. The material is then ground until the acetone vaporizes to the point that it has no odor of acetone.
This use of the acetone carrier also serves to homogenize all components, avoids the formation of rubber-enriched domains and agglomeration of agglomerated powders, and keeps the compounded rubber cool during milling, thereby It avoids premature polymerization of peroxide by heat-induced free radical initiator.

The material obtained is then approximately 2 mm thick and has a diameter of 8
Molded into 5mm 15-17g "putty" and sealed in saran bag. These "putties" are preferably stored in a refrigerator (2-7 ° C or 35-45 ^° F) until next use. PMMA beads (LUCTONE 199) made the mixture very smooth and could be easily filled into molds. EGDMA is
It is oily in nature and can be easily used for all grinding processes.

Physical data was obtained with this formulation as shown below.

According to this example, the powder components were first ball milled together and mixed on a cold rubber mill with gum gum, then the liquid components were added and further mixed. Finally the lauroyl peroxide initiator is added to the solution of acetone and mixed in the mill. The latter step performs several functions; a) a chemical initiator is added in the last step but does not appear to be activated by the heat generated in the rolls; b) the initiator is completely miscible C) acetone serves to destroy the agglomerates of powder components that can survive in ball and roll mills by dewatering and causing the powder particles to separate from each other; d) the total mixture It is homogenized, thereby preventing the formation of visible domains in the rubber-rich region; e) draining residual water; f) the whole material is kept cold by evaporating the acetone during the final mixing. Finally, all acetone is allowed to evaporate before removing the rubber from the mill.

The soft liner material described above is placed on the cut center portion and the flask is retest filled. Next, the composite denture is heat-cured. This embodiment provides a hard, creep-resistant, high-strength material around the denture, which is adjustable, abradable, and appropriately replaces the underlying soft tissue, while the bone structure of the jaw It provides a soft, deformable, low strength material that forms a soft cushion in the center of the upper denture.

The composite denture of the present invention was prepared by blending the fluoroelastomer with the components of the liner composition as described above, pressure molding the resulting composition into a wafer, and removing the spacer to fill a conventional gypsum mold flask. Widely formed by casting into the denture base dough. This composite denture
Next, heat treatment is performed to cure the liner and the denture base together to obtain a lined denture. In an exemplary process, denture waxing is boiled out of a conventional form of gypsum flask and filled with fresh denture base dough. 1-3
A mm silicone rubber spacer is placed on the tissue side of the mold space, a polyethylene sheet separator is placed, and the denture base dough is manufactured without over-extension and over-extension. 74
Pre-cure at 165 ^° F. for 30-45 minutes can be done to stiffen the denture base so that soft liner filling allows the denture base material after the spacer removal after cooling the flask. It does not replace.

[0050]

The most important advantage of the invention is that it can be used in commercial dental laboratories or dentist's offices because it does not use equipment that is subjected to high temperatures and / or pressures in the formation of composite dentures. Further, since the water absorption property and the accompanying swelling property of the dental liner material could be reduced, it became possible to improve the dimensional stability of the denture for a long time.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Paul Etch. Gebert United States Florida 32609 Gainesville Northwest Twenty First Avenue 1051 Apartment 48

Claims (23)

[Claims] 1. A soft, hardenable denture having a hardened denture base material, essentially phosphonitrile fluoroelastomer and at least one dimethacrylate crosslinker, and further containing at least one trimethacrylate crosslinker. A composite denture combined with a liner. 2. A composite denture according to claim 1, wherein the denture base material is predominantly a poly (methyl methacrylate) denture base. 3. The composite denture of claim 1, wherein the liner and the denture base material are co-cured to bond the liner and the denture base. 4. The composite denture according to claim 1, wherein the liner comprises a fluoroelastomer blended with a glycol ester of dimethacrylic acid and trimethylolpropane trimethacrylate. 5. The composite denture according to claim 4, wherein the liner further comprises a filler. 6. The liner is about 100 ° C. under atmospheric pressure conditions.
Alternatively, the compound denture according to claim 4, which can be cured in a closed denture flask at a lower temperature. 7. The composite denture according to claim 4, wherein the glycol ester of dimethacrylic acid is ethylene glycol dimethacrylate. 8. The composite denture of claim 5 wherein the ratio of trimethacrylate to dimethacrylate in the liner is about 40: 1 to about 1: 4. 9. a) Phosphonitrile A denture base material with a denture liner having a fluoroelastomer, at least one dimethacrylate crosslinker and at least one trimethacrylate crosslinker and curable at 100 ° C. or below at atmospheric pressure. Lining, and b) subjecting the lining denture base material to a temperature of about 100 ° C. or less to cure the denture liner and bond the liner with the cured denture base material to form a composite denture. And a hardened denture base material essentially having a phosphonitrile fluoroelastomer and at least one dimethacrylate crosslinker and further containing at least one trimethacrylate crosslinker. Shapes an essentially non-toxic composite denture with improved physical properties How to make. 10. The fluoroelastomer has the formula: (However, n is 3, 5, 7, 9 or 11 and m is 1
10. The method of claim 9, characterized by a plurality of repeating units of from 10,000 to 50,000). 11. The surface of the hardenable denture base material is C ₁ -C ₆ alkyl prior to lining with the denture liner material.
10. The method of claim 9 wherein the method is wet with a monomethacrylate monomer. 12. The method of claim 9 wherein the trimethacrylate is trimethylolpropane trimethacrylate. 13. The method of claim 12 wherein said dimethacrylate is a glycol ester of dimethacrylic acid. 14. The method of claim 9, wherein the liner further comprises a free radical initiator. 15. The glycol ester of dimethacrylic acid is polyethylene glycol ester, 1,6-hexamethylene glycol ester, ethylene glycol ester or tetraethylene glycol.
14. The method of claim 13, wherein the method is an ester. 16. The method of claim 9, wherein the liner further comprises a filler. 17. The method of claim 15 wherein the glycol ester of dimethacrylic acid is ethylene glycol dimethacrylate. 18. The filler is a hard acrylic resin or B
ASO ₄ or both, Claim 1.
Method of item 6. 19. The method of claim 9 wherein said denture base material is predominantly poly (methyl methacrylate) denture base dough. 20. The method of claim 14 wherein the initiator is lauroyl peroxide or benzoyl peroxide. 21. The method of claim 9 wherein the denture base material of paragraph (a) is pre-cured prior to lining with a denture liner. 22. The denture base material of claim (a) is a hardenable denture base material and the liner and denture base material of claim (b) are co-cured with the denture liner to bond them to each other. The method of claim 9 wherein: 23. The method of claim 21, wherein the pre-hardened denture base is a preexisting denture.