FR2872408A1 - Dental composition for dental prosthesis, contains cationically reactive compound(s), dental filler(s) treated with organosilicon coupling agent(s), cationic photoinitiator(s), optionally dispersant(s) and photosensitizer(s) - Google Patents

Abstract

A dental composition contains cationically reactive compound(s), dental filler(s), cationic photoinitiator(s), optionally dispersant(s) and photosensitizer(s). Filler is treated with organosilicon coupling agent(s) (F) and compound(s) (G) with reactive group (C). Component (F) comprises reactive group(s) (A) directly linked to silicon atom, and reactive group(s) (B) not directly linked to silicon atom reacting with group (C). A dental composition contains cationically reactive compound(s), dental filler(s), cationic photoinitiator(s), optionally dispersant(s) and photosensitizer(s). The dental filler(s) is treated with organosilicon coupling agent(s) (F) and compound(s) (G) with reactive group (C). Component (F) comprises reactive group(s) (A) directly linked to a silicon atom reacting with dental filler, and reactive group(s) (B) not directly linked to silicon atom reacting with group (C). The dispersant comprises organic (co)polymer(s). Independent claims are included for the following: (1) process for treating reinforcing filler, which involves treating the filler with a) with organosilicon coupling agent(s) and b) compound(s) (G) having reactive group; (2) reinforcing filler, which is obtained by the above method; (3) dental prosthesis, which is obtained by cross-linking the dental composition; and (4) dental restoration material, which is obtained by cross-linking the dental composition.

Description

Crosslinkable dental composition / stable cationic polymerizable

and high-load

  The field of the invention is that of dental compositions. More specifically, the dental compositions developed in the context of the present invention can be used for producing dental prostheses and for dental restoration.

  These dental compositions are conventionally epoxy resins, or photopolymerizable silicones or radical-polymerizable acrylate resins. These compositions also include particulate reinforcing fillers (e.g. hydrophobized silica), photoinitiators and optionally photosensitizers or even other functional additives such as pigments or stabilizers.

  Once mixed, these compositions are shaped and photocrosslinked into a mass of structure similar to that of the teeth.

  The fact that the filler consists of very fine particles 0.01 to 5 m) and of large specific surface area, is a limiting factor of its incorporation rate in the resin. The latter has a limited absorption capacity. As a result, the charge levels of such compositions seldom reach more than 45% by volume. This therefore penalizes the mechanical reinforcing function assigned to the particulate filler. Furthermore, the dental compositions are formulated with reinforcing fillers such as mineral glasses or very small particle size combustion silicas, including surface silanols and / or residual water react with the cationic functions that do not allow the storage of the compositions. This is also the case when these glasses or these fumed silicas are pretreated with silanes such as glycidyloxypropyltrimethoxysilane or glycidyloxypropyltriethoxysilane or else methacryloxypropyltrimethoxysilane. The reinforcing fillers interact with the reactive functions of the (photo) polymerizable / crosslinkable species and are thus at the origin of problems of instability of the dental composition during its storage which can reach durations of several months. This storage instability phenomenon is accentuated for heavily loaded compositions (e.g. overall charge rate> 50%).

  US Pat. No. 6,306,926 relates to dental compositions based on epoxy resins (eg UVRt 6105, EPON 828, GY281e), oxetane or vinyl ether, inter alia, polymerizable / crosslinkable, cationically and under irradiation, and optionally resins. (meth) acrylate radical polymerizable. In addition to the polymerization inductors that are cationic photoinitiators and optionally radical initiators as the case may be, these compositions comprise a microparticulate, radioopaque mineral filler, which is selected from the following metal compounds: oxides, halides, borates phosphates, silicates, carbonates, germanates , tetrafluoroborates, hexafluoro-phosphates, having an isoelectric point less than 7. This composition is such that its Barcol hardness is at least 10, after 30 min of cationic polymerization at 25 C.

  These resins have the disadvantage of not being perfectly transparent to the actinic radiation activating the polymerization by UV-visible radiation, which is detrimental to the reaction kinetics and therefore limits the possibilities of obtaining very thick photoreactive materials.

  The patent application FR-A-2 784 025 aims to remedy this problem by providing dental compositions based on polymerizable / crosslinkable silicone resins, cationically and under irradiation followed or not by a thermal post-crosslinking. These silicone resins have oxirane functionalities (epoxide, oxetane, etc.) or vinyl ether. Such compositions comprise: one or more crosslinkable and / or cationically polymerizable polydimethylsiloxanes carrying at least one of their ends reactive functions of formula: CH 2 -CH 2 - an effective amount of at least one initiator of Onium borate type:

F F

CH3 _ + \,; CH -y. 1- CH3, B F

_F F

  at least one photosensitizer, and at least one dental or inert reinforcing filler based on dental glasses or with polymethyl methacrylate or with optionally-treated fumed silica hexamethyldisilazane or polydimethylsiloxane with a surface area of 200 m 2 / g.

  These dental compositions are intended for the manufacture of prostheses or dental appliances and dental restoration.

  These silicones have the advantage over cationically crosslinking organic resins to be very transparent to UV visible light and thus to allow the production of very thick materials (several millimeters thick) photocrosslinked in a very short time ( less than one minute) with a UV lamp emitting in the visible range> 400 nm.

  However, these silicones are formulated with Lewis or Bronsted acidic reinforcing fillers, such as crushed glasses or very small particle size combustion silicas, whose surface silanols and / or residual water react with them. cationic functions. Such silicone formulations are therefore unstable on storage. In addition, when these silicones are formulated with thioxanthone type photosensitizers, a large chromatic variation is observed during the exposure with a view to photocrosslinking. This results in a pinkish color of the finished product (after exposure) which is not desirable from an aesthetic point of view.

  In addition to these problems, these silicone dental compositions remain perfectible with regard to the increase of the charge rate, so as to allow the improvement of the mechanical properties.

  Furthermore, patent application EP-A-1 050 291 discloses highly loaded dental compositions which are presented as having good mechanical properties and comprising from 10 to 70% by volume of filler (eg combustion silica). of particle size ((Dm) between 0.05 and 0.5 m (less than 50% by volume of particles of diameter c> 0.50 m), a radical-photopolymerizable acrylic monomer and an ester-type dispersant; phosphoric acid of formula: R - [- CO- (CH 2) 5 -O] n-PO 3 H 2 Such a teaching relating to radical dental compositions is in no way transposable to cationic dental compositions based on silicone. R - [- CO- (CH2) 5-O-in-PO3H2 are not suitable for cationic compositions, especially since they contain an important RPO3H2 acid residue which reacts in the presence of oxirane functional groups and adversely affects the stability of the composition.

  It therefore appears that the prior art does not provide a satisfactory solution to the double problem of storage stabilization of dental compositions based on cationically polymerizable units under UV (for example oxiranes) and dispersion of large amounts of charges in resin. In addition, the prior art does not provide solution either to the problem of residual color of the dental compositions after crosslinking.

  One of the essential objectives of the present invention is therefore to remedy this by providing new dental compositions based on cationically polymerizable units under UV (for example oxiranes), not having the disadvantages of the prior art on the storage stability plan and the limited charge rate.

  Another essential objective of the present invention is to provide novel cationic, polymerizable and / or crosslinkable dental compositions in the oral environment, which are not only stable in storage and highly loaded (eg> 50%) but which also have the advantage of be very transparent to UV-visible light and thus allow to obtain very thick materials (several millimeters thick) photocrosslinked in a very short time (less than a minute) with a UV lamp emitting in the visible range > 400 nm.

  Another essential objective of the present invention is to provide new cationic dental compositions, polymerizable and / or crosslinkable in the oral environment, which are stable, highly charged (eg> 50%), easy to prepare and economical but also which do not exhibit the disadvantage of generating parasitic staining after crosslinking.

  Another essential objective of the present invention is to provide a novel method for treating a reinforcing filler, in particular a dental filler, so that it can meet the constraints set out above when it is used in particular as reinforcing filler. in a dental composition.

  These and other objects are achieved by the present invention which first relates to a dental composition comprising: (1) at least one cationically reactive compound (A); (2) at least one dental load (B); (3) optionally at least one dispersant (C) comprising at least one organic polymer or copolymer; (4) at least one cationic photoinitiator (D); (5) and optionally at least one photosensitizer (E), said composition being characterized in that at least one dental filler (B) is treated: a) with at least one organosilicon coupling agent (F) and b) with at least one least one compound (G), said organosilicon coupling agent (F) comprising at least one reactive function (frA) directly linked to a silicon atom governing with the dental charge and at least one reactive function (frB) not directly linked to a silicon atom reactive with a reactive function (frC) of the compound (G).

  In a preferred embodiment: the reactive function (frA) directly bonded to a silicon atom of the organosilicon coupling agent (F) is an alkoxy, enoxy or hydroxy function; the reactive function (frB) not directly bonded to a silicon atom of the organosilicon coupling agent (F) is an oxirane, oxetane, hydroxyl, acid, carboxylic acid anhydride or diol function; and the reactive function (frC) of the compound (G) is an oxirane, oxetane, alkenyl ether or carbonate function.

  It is the merit of the inventors to have shown, surprisingly and unexpectedly, that it is possible to treat the surface of the load and thus increase the charge rate and thus ultimately strengthen the material while improving the storage stability of the composition. This stability translates into a limited period of use of several months or years.

  This technical solution is all the more interesting because it is economically viable and easy to implement.

  It is also interesting to note that this composition is satisfactory in terms of limiting the shrinkage after polymerization / crosslinking, which is quite appreciable in the dental application.

  According to a preferred variant of the invention, the dental composition according to the invention comprises at least one dental filler (B) treated by a process (I) comprising the following steps: a) mixing in a solvent medium, preferably in an aqueous medium the dental charge (B) and at least one organosilicon coupling agent (F) comprising at least one alkoxy and / or hydroxy function directly bonded to a silicon atom and at least one oxirane, oxetane, hydroxy, acid, d carboxylic acid and / or diol, b) the solvent is evaporated to obtain an intermediate dental charge (B-1), c) the intermediate dental charge (B-1) undergoes a heat treatment so as to allow the coupling reaction between the intermediate dental load (B-1) and the coupling agent (F) and thus to obtain an intermediate dental load (B-2), d) the intermediate dental load (B-2) is then mixed in a solvent medium with at least one compound (G) comprising at least one oxirane, oxetane, alkenyl ether and / or carbonate function, e) the solvent is evaporated to obtain an intermediate dental charge (B-3), and f) the intermediate dental charge (B-3) undergoes a thermal treatment of in order to allow the reaction between the intermediate dental charge (B-3) and the compound (G) and thus to obtain a treated dental charge (B-4).

  According to another preferred variant of the invention, the heat treatment of steps c) and f) of the process (I) is carried out by heating at a temperature of less than or equal to 200 ° C., preferably less than or equal to 165 ° C. and more preferably between 100 and 165 C.

  According to a preferred embodiment, the overall rate of dental loads (B) represents up to 85% by weight relative to the total weight of the dental composition and preferably between 60 and 80% by weight.

  Advantageously, the treatment of the dental charge (B) is carried out with up to 20% by weight, preferably between 1 and 15% by weight and even more preferably between 2 and 10% by weight of the compound (G ) relative to the total weight of the dental composition.

  Treatment of the dental charge (B) with the organosilicon coupling agent (F) is preferably carried out with compounds of formula: ## STR2 ## in which: R is a hydrogen or a linear or branched alkyl or alkenyl radical; C4, - R 'is a linear or branched alkyl radical, or a phenyl radical, - x is equal to 0, 1 or 2, and X being defined by the following formula: V 0 5 X = -E- (OD) CR ? R4 R3 R6 (M-1)

OH OH 2 I 6

  X = E (O-D) Z CR C) n C R R3 R4 \ R5 (M-2) V O X = E (O-D) CR2 e- R3 R4 (M3)

OH OH

  X = E (O-D) CR 2 - ()) n R 3 R 4 (CRRP (M-4) OOR x = E (O-D) = CR 2, C) p C R 3 R 4 R 6 (M-5)

O OH

HO O i s

  X = E (O-D) Z CR? Wherein: E and D which are identical or different radicals selected from linear or branched C1-C12 alkyls; z is 0 or 1; n is 0 or 1; p is equal to 0.1, 2, 3, 4, 5 or 6; - R2, R3, R4, R5, R6, R7, R8 are radicals, identical or different, representing a hydrogen atom or a linear or branched C1-C12 alkyl.

  As preferred organosilicon coupling agent (F), mention may be made of the following compounds: glycidyloxypropyltrimethoxysilane, the hydrolysis product of glycidyloxypropyltrimethoxysilane; glycidyloxypropyltriethoxysilane, the acid hydrolysis product of glycidyloxypropyltriethoxysilane; glycidyloxypropyldimethoxymethylsilane or the hydrolysis product, the beta- (3,4-epoxycyclohexyl) ethyltriethoxysilane silane or the hydrolysis product, the beta- (3,4-epoxycyclohexyl) ethyltrimethoxysilane silane or the hydrolysis product.

  Treatment of the dental charge (B) with the compound (G) is preferably carried out with a compound which is a monomer, an oligomer, an organic polymer or an organosiloxane comprising at least one oxirane, oxetane, alkenyl ether and / or carbonate function and even more preferably comprising at least one oxirane function.

  Preferably, the compound (G) comprises at least one function selected from the group consisting of the following structures (M-7) to (M-12): (M-7) (M-8) o (M -9) (M-10) (M-11) (CH 2) 3 O CH = CH 2 (M-12) (CH 2) 3 O CH = CH R "with R" representing a linear or branched C 1 -C 6 alkyl radical .

  According to a first preferred embodiment, the compound (G) is a silicone oligomer (G-1) or a silicone polymer (G-2). The silicone oligomer (G-1) and the silicone polymer (G-2) comprise: a) at least one unit of formula: (R) O 1 Z. Si O (-E (M-13) in which formula: - a = 0, 1 or 2, - R, identical or different, represents an alkyl radical, cycloalkyl, aryl, vinyl, hydrogen, alkoxy, preferably a lower alkyl C1-C6, - Z, identical or different, is a organic substituent having at least one oxirane, alkenyl ether, oxetane and / or carbonate function, and b) at least two silicon atoms.

  Advantageously, the silicone oligomer (G-1) and the silicone polymer (G-2) are chosen from the group consisting of the compounds of formulas: Me Me Me Me Sig Si O a) OO (S-1 ) Me Me Me Me Me Si, 'Si

O Me (S-2) (S-3) d)

  McMeM5vle pMeMeM (Me / \ (, "Si.p.Si Si- .. Si O- (S-4) e) Me Me Si Me p Me-Si Me Si Me Me e) (S-5)

R n (S-6)

  (n <1000) Me Me (o + p) <100> 1 g)) h (S-7) O CH, CH CH,

O

  CH, CH, H, CH, Si-CH 3 OI CH Si-CH; 7-CH2CH2H, CH, CI / CH, o (S-8) i)

O

  McMeM the Si.p, Si McMeM (Me (S-9) j) McMe? vIe / / Si.p, Si / p McMeM5le / y i () / Si.p, Si p (S-10) McMeMwle Si, p-Si k) O Me Me Me, Me O S i.0. S i O O O (S-11) 1) Me Me Me Me / - (O Si.O.Si

O

  (S-12) (S-13) with L = H; OH; Me; phenyl; C1-C12 alkyl; Cycloalkyl ClC6; groups m) CH., - CH2

CHI-CH n) or Me Me

f If 0 - Si}. 1 n r

  O 4 Ti, Me Me (S-14) with n <100; a <100 and m <100 o) mMeM \ 4 Si, oS n McMeM Si.o, -Si with n <100 (S-15) formulas in which R or Ro, identical or different, represents an alkyl, cycloalkyl radical aryl, preferably lower alkyl of 1 to 6 carbon atoms.

  Ar 0 Ar Ar 0 Si 0 Si Si S 16 Ar CHa Ar CH 1 O 70 S 17 S 18 CH 3 / CH a Si O, Si

O o S19 S20 S22 S23

Ar Ar, Ar Ar D D D Si Si

O O S24

  Ar D CH3 H3C Ar I, / Si \ Si o O Ar Ar Ar Ar Ar / Si, o. if

O

Ar CH Ar CH N. 3 1/3 o o S25

O

D CH D H3 If Si o O S26

D D

Yes Yes

O O S27 D p O

O S28

  ## STR1 ## If p O S29 S30

D D

D D O S31

  ## STR5 ## wherein CH 2 SiO 3 SiO 3 SiO 3 SiO 3 SiO 3 SiO 3 SiO 3 SiO 3 SiO 2 SiO 3 SiO 3 SiO 3 Yes Yes

D O n

O

  ## STR5 ## where ## STR5 ## where ## STR1 ## where ## STR2 ## where ## STR2 ## \ O /

O

Ar CH3 H3C / Al Si Si

O

  C CH3 Ar CH3H - CH3 // If Si / \ / n

O S37

O

  Ar Ar Ar CH3 \ i 1 / / If Si Si D 0 - Ar \ in S38 Ar / ArAr \ / Ar Ar \ CH3 Ar 0 If \ Si O Si OO S39 H3C CH3 H3C CH3 0 // Si \ Si 0 S40 Ar Ar i Si Si

We

  If 0 Si Si H CH3 H3C CH3 3.1 / 0 / Si Si \

O

  H3C CH3 H3C CH3 \ I 1 / Si / Si O D O D O S41

O S42

  ArH3 Ar CH3 / / O Si Si O Ar CH3Ar) --- \\ I 1 / / Si Si O D O S43 D O

O S44

  Ar ArAr Ar / \ / 0 If Si 0 D Ar ArAr Ar \! 1 / / If Si \ O D O n

O S45 or S46

D D D / \ /

Si3O-Si

O O

  - H3C CH3 (D) 2 if, Si o - S49 2 H3C CH3 1 / (D) 3 Si rSi S50 S47 H3C CH3 D Si S48 o 3 o H3C CH3 Si SI o

D If S51 3

  H3C CH3 o, where o S52 o S53 H3C CH3 VVVVCC S54 [() D 42- S i [() D k Si H3C CH3 I 0 S55 H3C CH3 Si (30 S56 S57 o 2 S58 o S59 3 o - 2 S61 H3C CH3 Si3 H3C CH3 1 / O / S1 Si H3C CH3 1/0 / Si 3 Si S62 H3C CH3H3C CH3-D Si / Si S63

O

H3C H3 H3C CH3 - D Si..Si

O

  _ 2 S64 H3C 0H3 Î H3 CH3 Si - D Si ,, Si / o - 3 S65 CH3 CH3 H3C \ \ CH3 OD S \ Si /

O O

CH

  ## STR5 ## wherein Si Si / Si o

CH

  H3C CH3-3-S67H, C H3) :: ## STR3 ##

CH3 CH3 n CH3 S68

  CH3 CH3 1 / / o-D if if H3C / 3C O S69

CH D D D D CH

  3 \ v \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \

O

S71 CH3

O

CH3_2 S72 H3C CH3CH3 D3 Si, dSi /

O

  S73 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 S84 If CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH2 CH3

C

  ## STR5 ## wherein the group D is a linear C 1 -C 12 alkyl, wherein S is a linear C 1 -C 12 alkyl; or branched and n is an integer from 1 to 20 (inclusive range boundaries), with Ar = aryl group.

  According to a second preferred embodiment, the compound (G) is a silane H3C o (G-3) of formula: (R) b (Z) a Si E formula in which: E -CH2-; -CH =; CH - R, which may be identical or different, represents an alkyl, cycloalkyl, aryl, vinyl, hydrogen or alkoxy radical, preferably a lower C 1 -C 6 alkyl, which may be identical or different, is an organic substituent containing at least one oxirane function; , alkenyl ether, oxetane and / or carbonate, and - a + b = 3.

  According to a preferred embodiment, the silane (G-3) is chosen from the group consisting of molecules (S-93) to (S-95): 1/1 / Si Si (S-93) (S-94) According to another preferred embodiment, the compound (G) is an organic compound (G-4) chosen from the group consisting of the molecules (S-96) to (S-104): 26 (S-96) O (CH 2) n O (S-97) IO p / I (CH 2) n O pp

O

  (S-98) formulas in which: n is an integer from 1 to 10 (inclusive).

O O

(S-99)

O

  (S-100) wherein O (S-103) with n <100 and D = linear or branched C1-C12 alkyl.

  Among the molecules of the type (S-103) one can choose the resin UVR6150 sold by the company DOW-CHEMICAL. o

  (S-104) with n <100 and the group D = linear or branched C1-C12 alkyl.

  For resins of the type (S-104), the one where n = 0 is particularly suitable for the invention.

  In general, the photochemical activation is carried out under UV radiation. More particularly, UV radiation with a wavelength of the order of 200 to 500 nm is used for producing dental prostheses and visible UV radiation of wavelength. greater than 400 nm for the realization of restoration materials. A wavelength greater than 400 nm allows crosslinking and / or polymerization in an oral environment.

  Actinic (photochemical) activation can be advantageously completed (or even replaced) by thermal activation.

  Preferably, the cationically reactive compound (A) is selected from the group of monomers and / or (co) polymers comprising: epoxies, vinyl ethers, oxetanes, spiroorthocarbonates, spiroorthoesters and their combinations.

  More preferably still, the cationically reactive compound (A) is a silicone oligomer (G-1), a silicone polymer (G-2), a silane (G-3) or an organic compound (G-4) such as defined above by the unit (M-13), the molecules (S-1) to (S-101) or.

  In the formula (M-13), the reactive functional groups Z that are particularly advantageous comprise at least one reactive functional group chosen from the following radicals: CH 3 CH 2 CH 1 / CH 2 CH-CH 3 (R-1) (R-2) (R) CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 CH 2 CH (CH) CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 R-9): (CH 2) 3 CH = CH R "- with R" representing a linear or branched C 1 -C 6 alkyl radical.

  According to an advantageous variant, the cationically reactive compound (A) is associated with an organic epoxy resin or oxetane representing less than 80% by weight of the fraction. Of the functional organic resins chosen, those whose mass percentage of reactive functional group is less than 20% and preferably less than 15% will be preferred. The volume shrinkage during the polymerization will decrease accordingly.

  The resins of formula (S-103) and (S-104): (S103) with n <100 and D = C1-C12 linear or branched alkyl are preferably chosen.

  Among the resins of the type (S-103) it is possible to choose the resin UVR6150 sold by the company DOW-CHEMICAL. o

  (S-104) with n <100 and the group D = linear or branched C1-C12 alkyl.

  For resins of the type (S-104), the one where n = 0 is particularly suitable for the invention.

  Different types of dental fillers (B) can be used to prepare the compositions according to the invention. The fillers are chosen according to the end use of the dental composition: these affect important properties such as the appearance, the penetration of the UV radiation, as well as the mechanical and physical properties of the material obtained after crosslinking and / or polymerization of the dental composition.

  As a reinforcing filler, it is possible to use treated or untreated pyrogenic silica fillers, amorphous silica fillers, quartz, glasses or non-vitreous fillers based on silicon oxides, for example of the type of those described in US Pat. US-6297181 (barium-free), zirconium, barium, calcium, fluorine, aluminum, titanium, zinc, borosilicates, aluminosilicates, talc, spherosil, yttrium trifluoride, fillers based on polymers in ground powder form such as inert or functionalized polymethyl methacrylates, polyepoxides or polycarbonates, ceramic whiskers (Si-C, Si-OC, Si-N, Si-NC, Si-NCO) , glass fibers.

  By way of example, mention may be made of: - inert fillers based on polymethyl methacrylate LUXASELF from the company UGL that can be used in the dental field and pigmented in pink, fillers of combustion silica treated with hexamethyldisilazane or polydimethylsiloxane with a specific surface area of 200 in / g, - charges of untreated fumed silica (Aerosil-AE200 marketed by DEGUSSA), quartz or glasses based on silicon oxides.

  According to one embodiment of the invention, the dental charge (B) is a mineral glass or a combustion silica.

  According to an advantageous characteristic of the invention, the dental fillers (B) represent up to 85% by weight, preferably between 50 and 85% by weight, even more preferably between 60 and 85% by weight, relative to the total weight of the dental composition.

  According to the invention, the dispersant (C) is selected from the group comprising: polyurethane / acrylate copolymers optionally salified with an alkylammonium, acrylic copolymers optionally salified with an alkylammonium, monodiesters of carboxylic acids, polyesters, polyethers polyurethanes, modified polyurethanes, polyol polyacrylates, copolymers thereof or mixtures thereof. Dispersants sold under the trade name DISPERBYK (from Byk) or SOLSPERSE (from Avecia) are particularly suitable for the invention. In particular, and by way of examples, mention may be made of commercial products: Disperbyk 164, Disperbyk 161, Disperbyk 166, Disperbyk 2070, Disperbyk 9075, Disperbyk 9076. The dispersants mentioned in the following patents may also be mentioned: - US Pat. B-5,882,393 describing dispersants based on polyurethanes / imidazoles-acrylates or epoxides; US Pat. No. 5,425,900 describing dispersants based on polyurethanes; US Pat. No. 4,795,796 describing dispersants based on polyurethanes / polyoxyalkyleneglycolmonoalkylether; the patent application WO-A-99/56864 describing dispersants based on polyurethanes / poly (oxyalkylene carbonyl): derivatives of ε-caprolactone and 5-valerolactone; and EP-B-0 403 197 describing graft polyolpolyacrylate dispersants comprising a polyurethane / polyvinyl / polyacrylate random copolymer and a polyoxyalkylene polyether.

  Quantitatively speaking, the dispersant (C) is present at 50 ppm to 1%, preferably 100 ppm to 5000 ppm.

  Preferably, the amine number of the dispersant (C) is less than or equal to 60, and more preferably still between 0.1 and 50 mg of potassium hydroxide per gram of dispersant (C).

  Advantageously, the acid number of the dispersant is less than or equal to 200, preferably less than or equal to 100, and more preferably between 1 and 60 mg of potash per gram of dispersant.

  The cationic photoinitiators (D) are chosen from onium borates (taken alone or in mixture with one another) of an element from groups 15 to 17 of the periodic classification [Chem. & Eng. News, vol.63, No. 5, 26 of 4 February 1985] or an organometallic complex of an element from groups 4 to 10 of the Periodic Table [same reference].

  According to a preferred embodiment, the cationic photoinitiator (D) is of the borate type and is chosen from those of which: a) the cationic entity of the borate is selected from: (1) onium salts of formula: [(R 9) -A (R10) ,,,] + (I) wherein: - A represents an element of groups 15 to 17 such as for example: I, S, Se, P or N; - R9 represents a carbocyclic or heterocyclic aryl radical in C6-C20, wherein said heterocyclic radical may contain nitrogen or sulfur as heteroelements; R10 represents R9 or a linear or branched C1-C30 alkyl or alkenyl radical; said radicals R9 and R10 being optionally substituted by a C1-C25 alkoxy, C 1 -C 25 alkyl, nitro, chloro, bromo, cyano, carboxy, ester or mercapto group, m and n are integers, with n + m = v + 1, v being the valency of the element A, (2) the oxoisothiochromanium salts, in this case those described in the patent application WO 90/11303, in particular the sulphonium salt of 2-ethyl 4-oxoisothiochromanium or 2-dodecyl-4-oxoisothio-chromanium and oxoisothiochromanium salts of structural formula V: Structure V Formula wherein: A represents n1 = an integer between 1 and 3; z l = an integer between 0 and 3; X represents a group of formula M'Y ', 1 (1) or of formula Q' (2), where in M1Y ', 1 (1): M' = Sb, As, P, B or Cl, Y 'represents a halogen (preferably F or Cl) or O and where r1 is an integer between 4 and 6, the formula Q1 (2) represents a R81-SO3 sulfonic acid where R81 is an alkyl or aryl group, or an alkyl or aryl group substituted by a halogen, preferably F or Cl, R101 represents an alkyl or cycloalkyl group, preferably C1-C20, or an aryl group, R1 represents a hydrogen, an alkyl, alkenyl, cycloalkenyl or cycloalkyl group, preferably a C 1 -C 20 group, or an aryl group, all R 21 being independent of one another, R 31 represents a hydrogen, an alkyl, alkenyl, cycloalkenyl or cycloalkyl group, preferably C20, or an aryl group, all R31 being independent of each other, R41 represents a hydrogen, a halogen, an alkenyl group, for example vinyl, cycloalkenyl alkyl, or cycloalkyl, preferably C 1 -C 20, an alkoxy or thioalkoxy group, preferably C 1 -C 20, a poly (alkylene oxide) group with up to 10 hydroxyl or alkyl-terminated alkylenic units ( C1-C12), an aryl group, an aryloxy or thioaryloxy group, R51 represents a halogen, an alkenyl group, for example vinyl, cycloalkenyl, alkyl, or cycloalkyl, preferably C1-C20, an alkoxy or thioalkoxy group, preferably C 1 -C 20, a poly (alkylene oxide) group with up to 10 hydroxyl terminated alkyl or C 1 -C 12 alkyl, aryl, aryloxy or thioaryloxy groups, R 61 represents hydrogen, a group alkyl, alkenyl, cycloalkenyl or cycloalkyl, preferably C 1 -C 20, or an aryl group, R 71 represents a hydrogen, an alkyl, alkenyl, cycloalkenyl or cycloalkyl, preferably C 1 -C 20, or an aryl group; and (3) organometallic salts of the following formula: (LI L2L3M) + q (II) wherein: M represents a group 4 to 10 metal, especially iron, manganese, chromium, cobalt, L1 represents 1 ligand linked to the metal M by electrons n, ligand chosen from the ligands R13-alkyl, 5cyclopendadienyl and T cycloheptratrienyl and the R6-aromatic compounds chosen from the ligands T16-benzene optionally substituted and the compounds having from 2 to 4 condensed rings, each cycle being capable of contributing to the valence layer of the metal M by 3 to 8 electrons n, - L2 represents a ligand bound to the metal M by n electrons, ligand selected from the Tl7-cycloheptatrienyl ligands and the aromatic compounds selected of the optionally substituted 716-benzene ligands and the compounds having 2 to 4 fused rings, each ring being capable of contributing to the valence layer of the metal M by 6 or 7 n electrons. L3 represents 0 to 3 identical or different ligands bonded to the metal M by α electrons, ligand (s) chosen (s) from CO and NO2 +; the total electronic charge q of the complex to which L1, L2 and L3 contribute and the ionic charge of the metal M being positive and equal to 1 or 2; and b) those whose borate anionic entity has the formula: [BXa Rb] - (III) wherein: a and b are integers ranging from 0 to 3 and from 1 to 4 with a + b = 4, - the symbols X represent: * a halogen atom (chlorine, fluorine) with a = 0 to 3, or * an OH function with a = 0 to 2, - the symbols R are identical or different and represent: a phenyl radical substituted with at least one electron-withdrawing group such as for example OCF 3, CF 3, NO 2, CN, and / or with at least 2 halogen atoms (especially fluorine), and this when the cationic entity is an onium of an element of groups 15 to 17, a phenyl radical substituted by at least one element or an electron-withdrawing group, in particular a halogen atom (especially fluorine), CF 3, OCF 3, NO 2, CN, and this when the cationic entity is an organometallic complex of a member of groups 4 to 10, or - an aryl radical containing at least two aromatic rings ics such as for example biphenyl, naphthyl, optionally substituted with at least one element or an electroattractant group, in particular a halogen atom including fluorine in particular, OCF3, CF3, NO2, CN, whatever the cationic entity.

  Without this being limiting, are given below more details on subclasses of onium borate and borate of organometallic salts more particularly preferred in the context of the use according to the invention.

  According to a first preferred variant of the invention, the species of the borate anionic entity which are particularly suitable are the following: 1 ': [B (C 6 F 5) 4] - 5': [B (C 6 H 3 (CF 3) 2) 4 ] 2 ': [(C6F5) 2BF2] - 6': [B (C6H3F2) 4] 3 ': [B (C6H4CF3) 4] - 7': [C6F5BF3] - 4 ': [B (C6F4OCF3) 4] - .

  According to a second preferred variant of the invention, the onium salts of formula (S-26) that can be used are described in numerous documents, in particular in US Pat. No. 4,026,705, US Pat. No. 4,032,673, US Pat. No. 4,069,056, US-A-4,136,102, US-A-4,173,476. Among these, the following cations will be particularly preferred: [(C8H17) -O- (C6H4) -I-C6H5 )] +; [C12H25- (C6H4) -I-05H5] +; [(C8H17-O- (C6H4)) 21] + [(C8H17) -O- (C6H4) -IC6H5)] +; [(C6H5) 2S- (C6H4) -O-C8H17] +; [CH3-C6H4-1-C6H4-CH2CH (CH3) 2] +; [(C 12 H 25- (C 6 H 4) -I- (C 6 H 4) -CH- (CH 3) 2] + [(C 12 H 25 -C 6 H 4) 21] +; [(C 6 H 5) 3 S] +; [CH 3 -C (C 6 H 4) -I - (C6H4) -CH (CH3) 2] + (115-cyclopentadienyl) (r16 toluene) Fe +; O15-cyclopentadienyl) (r16-cumene) Fe +, (r15 cyclopentadienyl) (116 methyl-1-naphthalene) Fe +; [(C6H5) -SC6H4-S- (C6H5) 2] +; [(CH3- (C6H4) -I- (C6H4) -OC2H51 +; [(CnH2n + 1-C6H4) 2I] + (with for the group CnH2n + 1, n = 1 to 18 and is linear or branched).

  According to a third preferred variant, the organometallic salts (3) of formula (S-27) that can be used are described in US-A-4,973,722, US-A-4,992,572, EPA-203,829, EP-A- 323,584 and EP-A-354,181. The organometallic salts most readily selected according to the invention are in particular: (R15-cyclopentadienyl) (r16-toluene) Fe +, 25. (R15-cyclopentadienyl) (116-methyl-l- naphthalene) Fe +, (cyclopentadienyl) (r16-cumene) Fe + bis (r-mesitylene) Fe +, bis (r16 -benzene) Cr + (P-16): [(C8H17) -O-C6H4-I- C6H5)] +, [B (C6F5) 4]; (P-17): [C 12 H 25 -C 6 H 4 -I-C 6 H 5] +, [B (C 6 F 5) 4]; (P-18): [(C8H17-OC6H4) 21] +, [B (C6F5) 4]; (P-19): [(C8H17) -O-C6H4-I-C6H5)] +, [B (C6F5) 4]; (P-20): [(C6H5) 2S-C6H4-O-C8H17] +, [B (C6H4CF3) 4] (P-21): [(C12H25-C6H4) 21] +, [B (C6F5) 4] In agreement with these three preferred variants, mention may be made, as examples of photoinitiators of the onium borate type, the following products: [Cl2H25-C6H4) 21] +, [B (C6H3 (CF3) 2 ]; [CH3-C6H4-I-C6H4-CH2CH (CH3) 2] +, [B (C6F5) 4]; As another literary reference for defining onium borates (1) and (2) and borates of organometallic salts (3), mention may be made of the entire content of patent applications EP 0 562 897 and 0 562 922. This content is integrally incorporated by reference in the present disclosure.

  As another example of an onium salt which can be used as a photoinitiator, mention may be made of those disclosed in US Pat. Nos. 4,138,255 and 4,310,469.

  Other cationic photoinitiators, e. g .: the salts of iodonium hexafluorophosphate or hexafluoro-antimonate, such as: - [CH3 - [(C6H4) -I - [(C6H4) -CH (CH3) 2] +, [PF6] -; [CH3- (C6H4) -I- (C6H4) -CH2CH (CH3) 2] +, [PF6] -; 20 - [(C12H25-C6H4) 21] +, [PF6] - or - the ferrocenium salts of these different anions.

  The photosensitizer contained within the dental composition according to the invention can be very varied in nature. In the context of the invention this corresponds in particular to one of the following formulas (IV) to (XXIV): R11 (P-22): [CH3-C6H4-I-C6H4-CH (CH3) 2] +, [B (C6F5) 4]; (P-23): (R15-Cyclopentadienyl) (1H-6-toluene) Fe +, [B (C6F5) 4] -; (P-24): (cyclopentadienyl) (1-methyl-1-naphthalene) Fe +, [B (C6F5) 4]; (P-25): (15-cyclopentadienyl) (116-cumene) Fe +, [B (C6F5) 4]; (P-26) (P-27) (P-28): [CH3-C6H4-I-C6H4-CH2CH (CH3) 2] +, [B (C6H3 (CF3) 2) 4]; and (P-29): [CH3-C6H4-1-C6H4-CH (CH3) 2] +, [B (C6H3 (CF3) 2) 4] Art II

O

X n R12

  Wherein: n = 1, Ar 1 represents an aryl radical containing from 6 to 18 carbon atoms, a tetrahydronaphthyl, thienyl, pyridyl or furyl radical or a phenyl radical bearing one or more substituents chosen from the group consisting of F, Cl, Br, CN, OH, C1-C12 linear or branched alkyls, -CF3, -OR13, -OPhenyl, -SR13, -SPhenyl, -SO2Phenyl, -COOR13, -O- (CH2CH = CH2), -O (CH2H4-O) mH, -O (C3H6O) mH, m being between 1 and 100, when n = 2, Art represents a C6-C12 arylene radical or a phenylene-T-phenylene radical; wherein T is -O-, -S-, -SO2-, or -CH2-, -X is OR14 or OSiR (R16) 2 or forms, with R11, -O-CH (R17) ) - RH represents a linear or branched C1-C8 alkyl radical unsubstituted or bearing a -OH group, -OR13, C2 -C8 acyloxy, -CF3, or -CN, a C3 or C4 alkenyl radical, a radical; C6 to C11 aryl, C7 to C9 phenylalkyl radical, R12 to one of the meanings given for R 11 or represents a radical - CH 2 CH 2 R 18, or else forms with R n, a C 2 -C 8 alkylene radical or a C 3 -C 9 oxaalkylene or aza-alkylene radical; - R 13 represents a lower alkyl radical containing from 1 to 12 carbon atoms, R14 represents a hydrogen atom, a C1-C12 alkyl radical, a C2-C6 alkyl radical carrying an -OH group, -OR13 or CN, a C3-C6 alkenyl radical, a cyclohexyl or benzyl radical, a phenyl radical optionally substituted with a chlorine atom or a linear or branched C 1 -C 12 alkyl radical, or a tetrahydropyranyl-2 radical, R 15 and R 16 are identical or different and each represents a radical; C1-C4 alkyl or phenyl; R17 is hydrogen, C1-C8 alkyl or phenyl; R18 is -CONH2, -CONHR 13, -CON (R13) 2 , - P (0) (OR13) 2 or pyridyl-2: ArO R19 formula (V) in which: - Ar2 has the same if wherein Ar1 of formula (IV) in the case where n = 1, - R19 represents a radical selected from the group consisting of an Ar2 radical, a linear or branched C1-C12 alkyl radical, a C6 cycloalkyl radical, C12 and a cycloalkyl radical forming a C6-C12 ring with the carbon of the ketone or a carbon of the radical Ar2, these radicals may be substituted by one or more substituents selected from the group consisting of - F, -Cl, -Br, -CN, -OH, -CF3 ,, -00 3, -SR 13, -COOR 13, linear or branched C 1 -C 12 alkyl radicals optionally bearing an -OH, -OR 13 and / or -CN group, and linear or branched C 1 -C 6 alkenyl radicals;

Y Y

Z R12 R12

  Ar 4 It is Ar 4 oE formula (VI) in which: R 12, which are identical or different, have the same meanings as in formula (IV), Y, which are identical or different, represent X and / or R 4, Z represents: direct bond, a divalent C 1 -C 6 alkylene radical, or a phenylene, diphenylene or phenylene-T-phenylene (linear or branched C 1 -C 12 alkyl) radical, or else form, with the two R 12 substituents and the two carbon atoms bearing these substituents, a cyclopentane or cyclohexane ring, a divalent group -O-R19-O-, -O-SiR15R16-O-SiR15R16-O-, or -O-SiR1 5R16-0- - R20 represents a C2-C8 alkylene radical, C4-C6 alkenylene or xylylene, - or else the entity:

Y Y

Z

  R12 R12 corresponds to o O - and Ar4 has the same meaning as Arl of formula (IV) in the case where n = 1.

  Thioxanthone family of formula (VII): R21) mm = 0 to 8, R21, identical (s) or different (s) substituents on the (s) aromatic ring (s), represent a linear or branched alkyl radical at C 1 -C 12, a C 6 -C 12 cycloalkyl radical, a radical Ar 1, a halogen atom, a group -OH, -O 3, -CN, -NO 2, -COOR 13, -OCOR 13, -N (R 13) 2 -O-R 13 (NR 13) 2 -CHO, -O-phenyl, -CF 3, -SR 13, -S-phenyl, -SO 2 -phenyl 15, -O-alkenyl or Si (R 13) 3.

  Xanthene family of formula (VIII): (R21) nn = 0 to 8 e family of xanthones of formula (IX): (R21) pp = 0 to 8 e family of naphthalene of formula (X): (R21) qq = 0 to 8 e family of the anthracene of formula (XI): (R21) rr = 0 to 10E phenanthrene family of formula (XII): (R21) ss = 0 to 10E pyrene family of formula (XIII): (R21) tt = 0to 10-fluorene family of formula (XIV): (R21) uu = 0 to 9E fluoranthene family of formula (XV): (R21), v = 0 to 10E chrysene family of formula (XVI): (R21) ww = 0 to 12E fluorene family of formula (XVII): (R21) x with x = 0 to 8, for example 2.7 dinitro 9-fluorenone, E family of the chromone of formula (XVIII): (R21) Y with y = 0 to 6E eosin family of formula (XIX): (R21) z R21) z (R21) z (R21) z with z = 0 to 5 with z = 0 to 6E family of erythrosine formula (XX): (R21) z (R21) z R21) z (R21) z with z = 0 to 5 with z = 0 to 6E family of biscoumarins of formula (XXII): O (R21) x (R21) x with x = 0 to 8 43 E family of thioxanthones of formula (XXIII): (R21), with y = 0 to 6E family of thioxanthones of formula (XXIV): with y = 0 to 6 For formulas (VIII) to (XXIII), the group R21 has the same definition as for the molecule (VII).

  Other sensitizers are usable. In particular, it is possible to use the photosensitizers described in documents US Pat. No. 4,939,069; U.S. 4,278,751; US 4,147,552 as well as the group consisting of compounds of the family of coumarins, conjugated diketones, fluorones, aminoketones, para-aminostyryl ketones and mixtures thereof.

  According to a preferred embodiment, the photosensitizer (E) is chosen from the group consisting of the compounds of the class of anthracenes, thioxanthones, camphorquinones, and phenanthrenequinone, as well as their mixtures.

  According to another preferred embodiment, the dental composition comprises, as photosensitizer (E), a salt of a thioxanthone substituted with at least one group comprising an ammonium function. The use of this type of photosensitizer has the advantage of avoiding parasitic staining when the dental composition is crosslinked for the production of dental prosthesis.

  According to a first variant of the invention, the associated anion of the salt of thioxanthone substituted with at least one group comprising an ammonium function is chosen from the following anions: a halide, BF4, PF6; SbFb; the anion (III) of formula [BXa Rb] "as defined above, RfSO3_; (RfSO2) 3C- or (RfSO2) 2N- with Rf being a linear or branched alkyl radical substituted with at least one d halogen, preferably a fluorine atom.

  According to a second variant of the invention, the photosensitizer (E), optionally in combination with at least one camphorquinone, a phenanthrenequinone and / or a substituted anthracene, has the formula:

OH / 1 X R23 R22 (XXV)

  in which formula: - R22 and R23 are identical or different and represent a hydrogen or an optionally substituted C 1 -C 10 alkyl radical, preferably R22 = R23 = methyl, - (X) being an anionic entity, preferably an halide; BF4, PF6; SbFb; the anion (III) of formula [BXa Rb] - defined as above, RfSO3-; (RfSO2) 3C- or (RfSO2) 2N-, with Rf being a linear or branched alkyl radical, substituted by at least one halogen atom, preferably a fluorine atom, and even more preferably (X) is chosen from borates following rules: [B (C6H3 (CF3) 2) 4] - and [B (C6F5) 4] -.

  According to one preferred embodiment, the photosensitizer (E), optionally in combination with at least one camphorquinone, a phenanthrenequinone and / or a substituted anthracene, has the formula:

OH

  ## STR1 ## In the context of the present invention, the photosensitizers have a residual absorption of UV light of between 200 and 500 nm, preferably 400. at 500 nm for dental prosthesis preparations. For the dental restoration, a photosensitizer having a residual absorption of U.V light above 400 nm will be preferred.

  According to a preferred variant, the photosensitizers will be chosen from those of families (VII), (X), (XI), (XIII), (XXIII), (XXIV) and (XXV). According to another embodiment, the phosensitizer is chosen from the group consisting of the following compounds: - (PS-30): 3- (3,4-dimethyl-9-oxo-9thioxanthenen-2-yloxy) -2-hydroxypropyl) -trimethylammonium chloride ; - (PS-31): 3- (3,4-Dimethyl-9-oxo-9-thioxanthen-2-yloxy) -2-hydroxypropyl) trimethylammonium tetrakis (pentafluorophenyl) borate; (PS-32): 3- (3,4-dimethyl-9-oxo-9-thi oxanthenyl-2-yloxy) -2-hydroxypropyl) trimethylammonium tetrakis (bis (trifluoromethyl) phenyl) borate; - (PS-33): phenanthrenequinone; - (PS-34): camphorquinone; - (PS-35): Acenaphthenequinone; - (PS-36): dibenzoylperoxide; (PS-37): 2-ethyl-9,10-dimethoxyanthracene; (PS-38): 9,10-diethoxyanthracene; (PS-39): 9,10-dibutoxyanthracene; - (PS-40): 9-hydroxymethylanthracene; (PS-41): 2-dimethylaminothioxanthone; (PS-42): 3-ethylcarboxy-7-methoxythioxanthone; (PS-43): 1-phenyl-thio-4-propoxythioxanthone; - (PS-44): 2-methoxythioxanthone; (PS-45): 2- (N, N-diethylaminopropoxy) thioxanthone; (PS-46): 2-isopropylthioxanthone; (PS-47): 1-chloro-4-propoxythioxanthone; (PS-48): 4-isopropylthioxanthone; (PS-49) (PS-50): OC8H17) - and mixtures thereof.

  In the context of the invention, the material obtained after crosslinking has significantly improved storage stability, mechanical strength, modulus of elasticity and compressive strength. When the thioxanthones of the family described by the formula (XXV) are used, there is an additional advantage in using the thioxanthones (PS-31) or (PS-32), optionally in combination with at least one camphorquinone, phenanthrenequinone and / or substituted anthracene, which is the absence of residual staining.

  In addition to the reinforcing fillers, pigments can be used to tint the dental composition according to the intended use and ethnic groups.

  For example, red pigments are used in the presence of microfibers for dental compositions used for the preparation of dental prostheses to simulate blood vessels.

  Pigments based on metal oxides (iron oxides and / or titanium and / or aluminum and / or zirconium, etc.) are also used for the dental compositions used for the preparation of restoration material, in order to obtain a material reticulated ivory color.

  Other additives may be incorporated into the dental compositions according to the invention. For example, biocides, stabilizers, flavoring agents, plasticizers and adhesion promoters.

  Among the additives that can be envisaged, use will advantageously be made of crosslinkable and / or polymerizable coreactants of organic type. These coreagents are liquid at room temperature or hot melt temperature below 100 C, and each coreactant comprises at least two reactive functions such as oxetane-alkoxy, oxetanehydroxy, oxetanealcoxysilyl, carboxy-oxetane, oxetane-oxetane, alkenylether-hydroxy, alkenylether-alkoxysilyl , epoxy-alkoxy, epoxy-alkoxysilyl, dioxolanedioxolane-alcohol, etc. For example, resins R70 and R71 may be mentioned.

  The dental compositions according to the invention can be used for many dental applications, and in particular in the field of dental prostheses, in the field of dental restoration and in the field of temporary teeth.

  The dental composition according to the invention is preferably in the form of a single product containing the various components ("monocomponent") which facilitates its implementation, particularly in the field of dental prostheses. Optionally, the stability of this product can be provided by organic derivatives with amine functions according to the teaching of the document WO 98/07798.

  In the field of dental prostheses, the product in the form "monocomponent" can be deposited using a syringe directly on the plaster model or in a key. Then, it is polymerized (polymerization possible successive layers) using a UV lamp (visible light spectrum 400 to 500 nm).

  In general, it is possible to achieve in 10 to 15 minutes a durable and aesthetic dental prosthesis.

  It should be noted that the products obtained from the dental composition according to the invention are non-porous. Thus, after a possible polishing with a felt brush, for example, the surface of the dental prostheses obtained is smooth and shiny and therefore does not require the use of varnish.

  The applications in the field of dental prostheses are essentially those of the adjunct prosthesis, which can be divided into two types: - total prosthesis in case of patient completely edentulous; Partial prosthesis due to the absence of several teeth resulting in either a temporary prosthesis or a skeletal device.

  In the field of dental restoration, the dental composition according to the invention can be used as a material for sealing the anterior and posterior teeth in different shades (for example, "VITA" shades), quick and easy to implement. .

  Since the dental composition is non-toxic and polymerizable in thick layers, it is not essential to polymerize the material in successive layers. In general, a single injection of the dental composition is sufficient.

  Preparations for dental prostheses and restoration materials are performed according to the usual techniques of the art.

  In the case of application of the dental composition to a tooth, the tooth can be pretreated with etching agent and then with a primer which can itself be photocrosslinkable or the dental composition can be prepared in admixture with a primer. hanging before use.

  The invention also relates to a method for treating a reinforcing filler, in particular a dental reinforcing filler, characterized in that the filler is treated: a) with at least one organosilicon coupling agent (F), and b) with at least one at least one compound (G), said organosilicon coupling agent (F) comprising at least one reactive function (frA) directly linked to a silicon atom reacting with the dental charge and at least one reactive function (frB) not directly linked to a silicon atom reactive with a reactive function (frC) of the compound (G).

  According to a preferred embodiment of the process according to the invention: the reactive function (frA) directly bonded to a silicon atom of the organosilicon coupling agent (F) is an alkoxy, enoxy and / or hydroxyl function; the reactive function (frB) not directly bonded to a silicon atom of the organosilicon coupling agent (F) is an oxirane, oxetane, hydroxy, acid, carboxylic acid anhydride or diol function; and the reactive function (frC) of the compound (G) is an oxirane, oxetane, alkenyl ether or carbonate function.

  According to another embodiment, the filler is treated: a) with at least one organosilicon coupling agent (F) comprising at least one alkoxy and / or hydroxy function directly bonded to a silicon atom and at least one oxirane and oxetane function; hydroxy and / or diol; and b) by at least one compound (G) comprising at least one oxirane, oxetane, alkenyl ether and / or carbonate function.

  The method according to the invention is particularly suitable for treating a dental load. This method (I) comprises the following steps: a) the dental filler (B) and at least one organosilicon coupling agent (F) comprising at least one alkoxy and / or hydroxy function directly bonded to a carbon atom are mixed in a solvent medium; silicon and at least one function oxirane, oxetane, hydroxy and / or diol, b) the solvent is evaporated to obtain an intermediate dental load (B-1), c) the intermediate dental load (B-1) is subjected to a heat treatment of in order to allow the coupling reaction between the intermediate dental load (B-1) and the coupling agent (F) and thus to obtain an intermediate dental load (B-2), 2872408 49 d) the intermediate dental load ( B-2) is then mixed in a solvent medium with at least one compound (G) comprising at least one oxirane, oxetane, alkenyl ether and / or carbonate function; e) the solvent is evaporated to obtain an intermediate dental charge (B-3 ), and f) the intermediate dental load (B-3) heat treatment so as to allow the reaction between the intermediate dental load (B-3) and the compound (G) and thus to obtain a treated dental load (B-4).

  According to a preferred embodiment, the heat treatment of steps c) and f) of the process (I) is carried out by heating at a temperature of less than or equal to 200 ° C., preferably less than or equal to 160 ° C. and even more preferably between 100 and 165 C.

  The organosilicon coupling agent (F), the compound (G) and the dental reinforcing filler (B) are as defined in the dental composition according to the invention.

  The invention also relates to a reinforcing filler obtained by the process according to the invention.

  The following Examples and Tests are given for illustrative purposes. They make it possible in particular to better understand the invention and to highlight some of its advantages and to illustrate some of its variant embodiments.

Examples and Tests

  Structures Me Me Me N / A o (S-1) (P-22) (P-29) o Lev- = s r r

OH

  + BÇbF5) 4 (PS-31) - Charge (B-1): Quartz type glass (particle size = 1.5 m, SiO 2 56%, SrO 14%, B 2 O 3 14%, Al 2 O 3 14%, F 2%) marketed by Schott company under the reference G018-163 Preparation of a thioxanthone with ammmonium borate functionality (S-61): OH +. B (CeFs) a / 1

OH

  ON + KÉ-B (CF / I ss) a (PS-30) (PS-31) 1.02 g of 3- (3,4-dimethyl) chloride are introduced in the dark into an opaque flask. 9-oxo-9H thioxanthen-2-yloxy) -2-hydroxypropyl) trimethylammonium (sold by Aldrich); 2,688 g of Kisbore KB salt (C6F5) 4 (prepared by Rhodia), 50 ml of isopropanol and is left stirring for 48 hours at room temperature. The mixture is then poured into demineralized water (200 ml). A yellow precipitate is formed. The suspension is filtered on Buchner and the solid is dried overnight in an oven at 100 C. The salt (PS-31) is obtained (mp 235 C, absorption maximum X max = 397.3 nm).

  Example 1 (comparative) Treatment of the filler (B-1) a) Treatment of the filler with a diol-functional coupling agent (F-2): The silane Glycidyloxypropyltrimethoxysilane or GLYMO of formula (F-1) and marketed by the Degussa company is hydrolysed in acidic medium following the following reaction :.

  HOR) (RO) -If acid pH M & IJ! AR \

OH

OH

  (F-1) (F-2) with R = methyl The compound (F-2) is in a more or less polycondensed form and is soluble in the aqueous phase.

  The solution used is a 40% solution of silane (F-2) with a pH = 34. 12.5 g of this 40% silane solution (F-2) are poured into a beaker and made up with 200 g of demineralized water. . 200 g of filler (B-1) are poured into this solution and the mixture is mixed for one hour with stirring for 1 hour at room temperature. The mixture is poured into a crystallizer and the batch is dried in an oven for 16 hours at 150 ° C. The filler is then sieved on a web of 250 microns.

  b) Treatment with an oxirane functional coupling agent) For comparison, we hydrolyzed the silane glycidyloxypropyltrimethoxysilane in a neutral medium and we removed a large part of the methanol from the hydrolysis reaction by distillation. Analysis by 1 H NMR reveals that the epoxide function is not hydrolysed when cold storage this solution for a few weeks.

  Neutral pH (OH) (HO) If O-MeOH (OR) (F-1) (F-3) A 40% silane solution (F-3) at pH = 7 is used.

  12.5 g of this 40% solution are poured into a beaker and made up with 200 g of demineralized water. 200 g of filler (B-1) are poured into this solution and mixed for one hour with propeller stirring at room temperature. The whole is poured into a crystallizer and the charge is dried in an oven for 16 hours at 150 ° C. The charge is then sieved on a web of 250 microns.

  c) Properties of the dental compositions 11.625 g of oxirane-functional siloxane resin (S-1) are loaded in a centrifugal mixer (Hauschild brand).

  1.125 g of a 4% solution of dispersant (C-1) (marketed by Byk under the reference Disperbyk-164x) is added. The mixture is stirred with the centrifugal mixer at 3000 rpm and 3 g of ytterbium trifluoride are added. Again (OR) (RO) Si O (OR) 16s with the centrifugal mixer at 3000 rpm, 1.25 g of photoinitiator system (P) containing 30% photoinitiator (P-22) and 0.89% by weight are added. photosensitizer of formula (PS-31) in solution in (S-1).

  The mixture is agitated 16s with the centrifugal mixer at 3000 rpm at room temperature and then g of the filler (B-1): - untreated (Formulation h), or treated according to a) (Formulation la); - or treated according to b) (Formulation lb).

  16s are stirred with the centrifugal mixer. 3 grams of a charge of the type of fumed silica (B-2) (SiO 2> 99% and marketed by the company Degussa under the reference OX50) are then added and the mixture is stirred for 16 hours. Finally, 5 g of a charge of the type of fumed silica (B-3) sold by the company Degussa under the reference R202 are added and the mixture is stirred for 16 hours.

* The evolution of the viscosity over time is followed for the three formulations. Note the moment when the composite formulation is gelled and is no longer manipulable. The results are shown in Table 1.

Table 1.

  Comparative Stability at 25 C Formulation lt <24h Formulation <24h Formulation lb 48h Example 2 (Invention) a) Treatment with the oxirane functional resin (S-1) of the fillers obtained in Example 1a) A solution of 2, 5% by weight of oxirane functional resin (S-1) is prepared in acetone.

  100 g of filler (B-1) treated according to Example 1a) is poured onto 100 g of this 2.5% solution and stirred mechanically at room temperature for about one minute. The mixture is then poured into a crystallizer and the acetone is evaporated at room temperature.

  The residue is heated for 16 hours at 150 ° C. in order to polymerize the oxirane-functional resin (S-1) on the surface of the charge. The filler is then sieved to obtain a powder.

  b) Treatment with the oxirane-functional resin (S-1) of the charges obtained in

examples lb)

  A 2.5% by weight solution of oxirane functional resin (S-1) is prepared in acetone.

  100 g of filler (B-1) treated according to Example 2b) is poured onto 100 g of this 2.5% solution and stirred mechanically at room temperature for about one minute. The mixture is then poured into a crystallizer and the acetone is evaporated at room temperature. The residue is heated for 16 hours at 150 ° C. in order to polymerize the oxirane-functional resin (S-1) on the surface of the charge. The filler is then sieved to obtain a powder.

  c) Properties of the Dental Compositions The two fillers of Examples 2a) and 2-b) are formulated in the same way as in Example 1-c), the overall load ratio is 72% by weight relative to the weight of the composition, to obtain two dental compositions (formulations (2a) and (3b) respectively) whose stability and evolution over time are monitored.

Table 2.

  Invention Treatment Stability at 25 C Formulation (2a) a) Solution at 2.5% by weight of resin (S-1) 1 month Formulation (2b) b) Solution at 2.5% by weight of resin (S-1) 1 week Comparison results between: - formulations (la) and (2a), and - formulations (Ib) and (2b) show a marked improvement in stability.

  Example 3 (Invention) Variation of the content of oxirane-functional resin (S-1) Example 2a) is repeated by varying the level of oxirane-functional resin (S-1) during the treatment of the filler (B-1). ).

  Then a dental composition is formulated as in Example 2c).

  The exact composition corresponds to the following formulation (the overall degree of charge is 66% by weight relative to the weight of the composition): - Resin with oxirane function (S-1)> 29.25 g - 4% Dispersant Solution (C -1)> 2.25 g - Photoinitiator system (P) (see example 1): (P-22) + (PS-31)> 2.5 g - Ytterbium trifluoride> 6 g - Charged (B-1) treated> 50 g - Untreated load (B-2) Silica of combustion OX50> 5 g - Untreated load (B-3) Silica of combustion R202> 5 g One follows the evolution of the epoxy rate by potentiometric assay in solution of the composite in the titrant solution of perchloric acid.

Table 3.

  Dental Compositions% by Weight of Resin Stability Rate at 25 C (S-1) in Acetone for Conversion of (Months) Treatment of Epoxy Load% After 26 (B-1): Days Control Formulation (1 t ) 0 Not measurable 0 Formulation (3a) 1 23 1 Formulation (3b) 2.5 19 3 Formulation (3c) 5 16> 12 months Example 4 (Invention): Preparation of a dental composition with an overall loading rate of 70% by weight relative to the weight of the composition. 11.5 g of oxirane-functional siloxane resin (S-1) are charged to a Hauschild centrifugal mixer. 2.25 g of a 4% solution of dispersant (C-1) marketed by Byk under the reference Disperbyk-164 are added. The mixture is stirred with the centrifugal mixer at 3000 rpm and 3 g of ytterbium trifluoride are added. The centrifuge is again stirred at 150 rpm for 16 minutes and 1.25 g of a photoinitiator system (P) containing 30% by weight of photoinitiator (P-22) and 0.89% by weight of photosensitizer based on (PS-31) in the resin (S-1). The mixture is agitated 16s with the centrifugal mixer at 3000 rpm at room temperature, then 27 g of the charge (B-1) treated according to Example 2a) and then according to Example 3 (treatment of the charge (B-1)) are added. with a solution of 5% by weight of the resin (S-1) in acetone). 16s are stirred with the centrifugal mixer. 2.5 g of fumed silica (B-2) (marketed by Degussa under the reference OX50, SiO2> 99%) treated as the filler (B-1) are added and the mixture is stirred for 16 hours. 2.5 g of combustion silica (B-3) (sold by the company Degussa under the reference R202) are then added and the mixture is stirred for 16 hours.

  The evolution of the viscosity over time is followed for the formulation with treated fillers. The latter is stable for more than 1 year at 25 C.

  Specimens as described in the ISO 4049 standard are crosslinked with a halogen lamp of the Demetron Optilux 500 type (irradiation time: twice 40s).

  The bending strength measured according to the ISO-4049 standard is 90 MPa +/- 10 with a flexural modulus of 9000 MPa.

  The crosslinking depth is 4mm after irradiation 40s.

  The volume shrinkage calculated from the densities measured before and after polymerization is: -1.6% +/- 0.2 - Oxirane functional resin (S-1)> 11.5 g - Dispersant solution (C-1)> 2.25 g - Photo-initiator system (P): (P22) + (PS-31)> 1.25 g - Untreated Ytterbium trifluoride> 3 g Charge (B-1) treated> 27 g - Charge (B-2) treated , Silica of combustion OX50> 2.5 g - Untreated feed (B-3), Silica of combustion R202> 2.5 g Example 5 (Invention) We compared the impact of the nature of the photosensitizers on the coloration of the composition after irradiation with a dentist's lamp. We reproduced Example 4 by modifying the nature and quantity of the photosensitizer introduced into the composition.

  The dental compositions described in Examples 2 to 5 are crosslinked to a thickness of 2 to 3 mm with an irradiation time of between 30 seconds and 1 minute using an Optilux Demetron lamp. It is measured using a chromameter or colorimeter. The exact composition corresponds to the following formulation (the overall charge ratio is 70% by weight relative to the weight of the composition): Minolta CR200 values L *, a * b * after% hour of crosslinking on a white background and after 5 days after crosslinking.

  From this we deduce the chromaticity difference obtained Oc defined such that Ac = [(Aa) 2+ (Ab) 2] I / 2 It is found that the crosslinking with a dentist lamp Demetron Optilux 500 dental compositions formulated with the photosensitizer (PS 31) alone or in combination with other photosensitizers for example (PS-39); (PS-34) and (PS-33) do not give rise to a staining defect (no pinking phenomenon during irradiation with a color value a> 1 immediately after irradiation).

Table 4

  Example Photosensitizer (s) Concentiation (s) ppm T = 1/4 hours; L a, b T = 5 together; L, a, b Oc L * a * b * L * a * b * 5-a PS-47 67 69.15 2.87 7.68 73.4 -0.5 9.55 3.85 5-b PS-30 220 71.1 1.70 16.2 75.85 -1.51 14.75 3.5 5-c PS-31 220 76.35 0.29 12.4 78.06 -0.63 11 , 1.08 5-d PS-31 170 72.8 1.01 10.02 75.24 -0.4 8.73 1.51 5-e PS-31; PS-39 170; 130 73.4 0.46 14.16 76.47 -1.0 13.04 1.84 5-f PS-31; PS-34; PS-39 170; 100; 120 70.1 -0.21 15.68 73.69 -1.33 13, 94 2.07 5-g PS-31; PS-33; PS-39 170; 50; 110 69.08 1.41 15.58 73.42 -0.79 15.07 2.26 5-h PS-34; PS-39100; 1 60 Insufficient kinetics for crosslinking in 1 minute on 3 mm The use of the combination of thioxanthone (PS-31) makes it possible to overcome not only the color problems but also the kinetic problems that are encountered when using only camphorquinone (PS-34) or camphorquinone in combination with the anthracene derivative (PS-39) at low concentration (less than 0.1% case of example 5-h).

  Example 6 (Invention) Example 5 is repeated, replacing: the photoinitiator (P-22) with the photoinitiator (P-29); and the photoinitiator system (P) by the photoinitiator system (P ') containing 30% by weight of photoinitiator (P-29) and 0.89% by weight of photosensitizer (PS-31) in the resin ( S-1).

  Chromatic difference: - after% hr of crosslinking on a white background, L *, a *, b * = 72,1; 0.10; 9.53 respectively; and after 5 days, L *, a *, b * = 75; -0.25; 8.1 respectively. => Ac = [(Aa) 2+ (Ab) 2] l; 2 = 1.47.

Claims (4)

  A dental composition comprising: (1) at least one cationically reactive compound (A); (2) at least one dental load (B); (3) optionally at least one dispersant (C) comprising at least one organic polymer or copolymer; (4) at least one cationic photoinitiator (D); (5) and optionally at least one photosensitizer (E), said composition being characterized in that at least one dental filler (B) is treated: a) with at least one organosilicon coupling agent (F) and b) with at least one at least one compound (G), said organosilicon coupling agent (F) comprising at least one reactive function (frA) directly linked to a silicon atom reacting with the dental charge and at least one reactive function (frB) not directly linked to a silicon atom reactive with a reactive function (frC) of the compound (G).   2- Dental composition according to claim 1 wherein: - the reactive function (frA) directly bonded to a silicon atom of the organosilicon coupling agent (F) is an alkoxy, enoxy or hydroxy function; the reactive function (frB) not directly bonded to a silicon atom of the organosilicon coupling agent (F) is an oxirane, oxetane, hydroxy, acid, carboxylic acid anhydride or diol function; and the reactive function (frC) of the compound (G) is an oxirane, oxetane, alkenyl ether or carbonate function.   3 - dental composition according to one of the preceding claims wherein at least one dental load (B) is treated by a method (I) comprising the following steps: a) mixing in a solvent medium the dental load (B) and at least an organosilicon coupling agent (F) comprising at least one alkoxy, enoxy and / or hydroxy function directly bonded to a silicon atom and at least one oxirane, oxetane, hydroxyl, acid, carboxylic acid anhydride and / or diol function, b) the solvent is evaporated to obtain an intermediate dental load (B-1), c) the intermediate dental load (B-1) undergoes heat treatment so as to allow the coupling reaction between the intermediate dental load (B-1) ) and the coupling agent (F) and thus to obtain an intermediate tooth load (B-2), d) the intermediate tooth load (B-2) is then mixed in a solvent medium with at least one compound (G) comprising at least one oxirane function, oxetan e, alkenyl ether and / or carbonate, e) the solvent is evaporated to obtain an intermediate dental charge (B-3), and f) the intermediate dental charge (B-3) undergoes a heat treatment so as to allow the reaction between the intermediate dental load (B-3) and the compound (G) and thus to obtain a treated dental load (B-4).   4 - dental composition according to claim 3 wherein the heat treatment of steps c) and f) of the process (I) is carried out by heating at a temperature less than or equal to 200 C, preferably less than or equal to 165 C and more preferably between 100 and 165 C.   - Dental composition according to one of the preceding claims wherein the overall rate of dental loads (B) is up to 85% by weight relative to the total weight of the dental composition and preferably between 60 and 80% by weight.   6 - Dental composition according to one of the preceding claims wherein the treatment of the dental charge (B) is carried out with up to 20% by weight, and preferably between 1 and 15% by weight, of the compound (G and / or up to 20% by weight, preferably between 1 and 15% by weight of the compound (F) relative to the total weight of the dental composition.   7 - Dental composition according to one of the preceding claims wherein the organosilicon coupling agent (F) is of formula: (F) in which formula: - R is a hydrogen or a linear or branched C 1 -C 4 alkyl radical; R 1 is a linear or branched alkyl radical, or a phenyl radical, - x is 0, 1 or 2, and - X is defined by the following formula: X = E (OD) X = -E- ( OD) o / CR? C) n-C-R R4 R3 R6 (M-1) OH OH I 6   CR 1) n-C-R R 3 R 4 R 5 (M-2) V 0 CR () - - R 3 R 4 (C 7 RSp X = -E- (O-D) (M-3) OH OH   X = -E- (OD) CR2 -, (C) n -R3 R4 78 (C RRP (M-4) ooo IX = -E- (OD) = CR1 / (C) pC-R R3 R4 ' R6 (M-5) 0 OHHO OX = -E- (OD) Z CR? SC) pCR R3 R4 R6 (M-6) with: - E and D are identical or different radicals chosen from C 1 alkyls; C 12 linear or branched, - z is 0 or 1, - n is 0 or 1, - p is 0, 1,2,3,4,5 or 6.   - R2, R3, R4, R5, R6, R7 and R8 which are identical or different radicals representing hydrogen or a linear or branched C1-C12 alkyl.   8 - dental composition according to claim 7 wherein the organosilicon coupling agent (F) is selected from the group consisting of the following compounds: glycidyloxypropyltrimethoxysilane, the hydrolysis product of glycidyloxypropyltrimethoxysilane; glycidyloxypropyltriethoxysilane, the acid hydrolysis product of glycidyloxypropyltriethoxysilane; glycidyloxypropyldiinethoxymethylsilane or the hydrolysis product, beta (3,4-epoxycyclohexyl) ethyltriethoxysilane or the hydrolysis product, beta- (3,4-epoxycyclohexyl) ethyltrimethoxysilane or the hydrolysis product.   9 Dental composition according to one of the preceding claims wherein the compound (G) is an organic or organosiloxane monomer, oligomer or polymer comprising at least one oxirane function, oxetane, alkenyl ether and / or carbonate - - Dental composition according to claim 9 wherein the compound (G) comprises at least one selected from the group consisting of the following structures (M-7) to (M-12): (M-8) (M-9) (M-10) (M 11 (M-12) (CH 2) 3 O CH = CH 2 (CH 2) 3 O CH = CH R "with R" representing a linear or branched C1-C6 alkyl radical.   11 - Dental composition according to one of the preceding claims wherein the compound (G) is a silicone oligomer (G-1) or a silicone polymer (G-2).   12 - dental composition according to claim 11 wherein the silicone oligomer (G-1) and the silicone polymer (G-2) comprise: a) at least one unit of formula: (R) 0 Z tii 0 (3.1.2 (M-13) in which: - a = 0, 1 or 2, - R, which is identical or different, represents an alkyl, cycloalkyl, aryl, vinyl, hydrogen or alkoxy radical, preferably a lower C 1 -C 6 alkyl; Z, which may be identical or different, is an organic substituent comprising at least one oxirane, alkenyl ether, oxetane and / or carbonate function, and b) at least two silicon atoms.   13 Dental composition according to claim 12 wherein the silicone oligomer (G-1) and the silicone polymer (G-2) are chosen from the group consisting of compounds of formulas: Me Me / me O O a)   Me Me Me Me Sig, If <O Me Me b) (S-2) c) Me Me Me Sig O If (S-3) d) (S-4) Me Me / Si e) (S- 5) (R 1) R n O (R) O n (n <1000) (S-6) M e Si 0 (p) 10 or 1 (S-7) O CH, CH 2 CH 2 CH 2 CH 3 CH 3 CH 3 CH 3 CH 3 CH O g) h)   \ CH CH, - (S-8) i) McMeM e McMeMMe SiO, Si Si3O, Si J) (S-9) McMeW / Ie / Si.Q, Si / O McMeM e 4) Si.Q, SI O   (S-10) McMeMe Si3O, Si Me Me Me Me O / Si.O Si O k) (S-11) 1) Me me Me Me O Si.O.SiO (S-12) m) (L) MeMe Yes O WHO If O   (S-13) L = H; OH; Me; phenyl; C1-C12 alkyl; C 1 -C 6 cycloalkyl or the following groups: ## STR2 ## ) with n <100; a <100 and m <100 0) McMeMe e / O McMeM, Si.O, Si Si 3 O. Si O n with n <100 (S-15) in which R or Ro, identical or different, represents an alkyl radical, cycloalkyl, aryl, preferably a lower C 1 -C 6 alkyl.   14 - Dental composition according to any one of the preceding claims characterized in that the compound (A) cationically reactive is selected from the group 20 of monomers and / or (co) polymers comprising: epoxies, vinyl ethers, oxetanes, spiroorthocarbonates, spiroorthoesters and their combinations.   Dental composition according to claim 14, wherein the cationically reactive compound (A) is constituted by at least one crosslinkable and / or polymerizable oligomer (G-1) or silicone polymer (G-2) which is liquid at room temperature or thermofusible at a temperature below 100 C, and comprising: a) at least one unit of the following formula: Z Si-O (3-a) / 2 R) a (M-13) in which: a = 0, 1 or 2, - R, which may be identical or different, represents an alkyl, cycloalkyl, aryl, vinyl, hydrogen or alkoxy radical, preferably a lower C 1 -C 6 alkyl, Z, identical or different, is an organic substituent comprising at least one reactive function oxirane, alkenylether, oxetane, dioxolane and / or carbonate, and b) at least two silicon atoms.   16 - dental composition according to claim 15, characterized in that the unit (M-13) comprises groups Z selected from the group consisting of the following radicals (R-1) to (R-9): CH2-CH2N.   (R-1) (R-2) (R-3) CH 2 CH 2 CH 2 fl a (R-4) s-CH 2 CH 2 -CHI H C f.   N.0 ,. 0 (R-5) (R-6) CH 3 CH 3 CH 2 CH 2 CH 3 CH 2 CH 2 CH 3 CH (CH 2) 3 O CH 2 CH 2 (R-9) (CH 2) 0 CH = CH R "with R" representing a linear or branched C1-C6 alkyl radical.   17 - Dental composition according to any one of the preceding claims, characterized in that the cationically reactive compound (A) is chosen from the group consisting of the compounds (S-1) to (S-15) described in US Pat. claim 13.   18 - Dental composition according to any one of the preceding claims, characterized in that the cationic photoinitiator (D) is of the borate type and is chosen from those of the formula of which: a) the cationic entity of the borate is selected from: ) onium salts of formula: [(R 9) "- A - (R 10) n, +) (I) in which formula: - A represents an element of groups 15 to 17 such as, for example: I, S , Se, P or N, - R9 represents a C6-C20 carbocyclic or heterocyclic aryl radical, said heterocyclic radical being able to contain, as heteroelements, nitrogen or sulfur; R1 represents R9 or a linear or branched alkyl or alkenyl radical; wherein R9 and R10 are optionally substituted with C1-C25alkoxy, C1-C25alkyl, nitro, chloro, bromo, cyano, carboxy, ester or mercapto, m and n are numbers; integers, with n + m = v + 1, v being the valency of element A, (2) oxoisothioch salts omanium and (3) the organometallic salts of the following formula: (L 1 L 2 L 3 M) + q (II) in which formula: M represents a metal of group 4 to 10, in particular iron, manganese, chromium, cobalt, L 1 represents 1 ligand bound to the metal M by n electrons, ligand selected from β-alkyl, η-cyclopentadienyl and γ-cyclohepatratrienyl ligands and aromatic compounds selected from optionally substituted η 6 -benzene ligands and compounds having 2 to 4 fused rings each cycle being capable of contributing to the valence layer of the metal M by 3 to 8 n electrons, L 2 represents a ligand bound to the metal M by electrons Tc, a ligand selected from among the 7-cycloheptatrienyl ligands and the compounds aromatic compounds selected from optionally substituted 116-benzene ligands and compounds having 2 to 4 fused rings, each ring being capable of contributing to the valence layer of the metal M by 6 or 7 electrons 7t, - L3 represented from 0 to 3 identical or different ligands bonded to the metal M by electrons 6, ligand (s) chosen (s) from CO and NO2 +; the total electronic charge q of the complex to which L1, L2 and L3 contribute and the ionic charge of the metal M being positive and equal to 1 or 2; and b) the anionic borate moiety has the formula: [BXa Rb] (III) wherein: - a and b are integers ranging from a to 0 and from 1 to 4 with 30 a + b = 4, - the symbols X represent: * a halogen atom (chlorine, fluorine) with a = 0 to 3, or * an OH function with a = 0 to 2, - the symbols R are identical or different and represent: a phenyl radical substituted with at least one electron-withdrawing group such as for example OCF 3, CF 3, NO 2, CN, and / or with at least 2 halogen atoms (especially fluorine), and this when the cationic entity is an onium a member of groups 15 to 17, a phenyl radical substituted by at least one element or an electron-withdrawing group, especially a halogen atom (especially fluorine), CF 3, OCF 3, NO 2, CN, and this when the cationic entity is an organometallic complex of an element of groups 4 to 10, or - an aryl radical containing at least two aromatic rings es such as, for example, biphenyl, naphthyl, optionally substituted with at least one element or an electron-withdrawing group, in particular a halogen atom, in particular fluorine, OCF 3, CF 3, NO 2, CN, whatever the cationic entity.   19- The composition as claimed in claim 18, characterized in that the cationic photoinitiator (D) is chosen from the group consisting of the following compounds: (P-16): [(C8H17) -O-C6H4-I-C6H5)] +, [B (C6F5) 4]; (P-17): [Cl2H25-C6H4-I-C6H5] +, [B (C6F5) 4]; (P-18): [(C8H17OCH6H4) 21] +, [B (C6F5) 4]; (P-19): [(C8H) -O-C6H4-I-C6H5)] +, [B (C6F5) 4]; (P-20): [(C6H5) 2S-C6H4-O-C8H17] +, [B (C6H4CF3) 4] (P-21): [(C12H25-C6H4) 21] +, [B (C6F5) 4 ]; (P-22): [CH3-C6H4-Cl6H4-CH (CH3) 2] +, [B (C6F5) 4]; (P-23): (1) 5-cyclopentadienyl) (1] 6 toluene) Fe +, [B (C6F5) 4]; (P-24): (R15-Cyclopentadienyl) (116 methyl-1-naphthalene) Fe +, [B (C6F5) 4]; (P-25): (r15-cyclopentadienyl) (r) 6-cumene) Fe +, [B (C6F5) 4]; (P-26): [(C12H25-C6H4) 21] +, [B (C6H3 (CF3) 2]; (P-27): [CH3-C6H4-I-C6H4-CH2CH (CH3) 2] +, [ B (C6F5) 4]; (P-28): [CH3-C6H4-I-C6H4-CH2CH (CH3) 2] +, [B (C6H3 (CF3) 2) 4Y; and (P-29): [CH3 - C6H4-I-C6H4-CH (CH3) 2] +, [B (C6H3 (CF3) 2) 4] Dental composition according to claim 1, characterized in that the cationic photoinitiator (D) is an iodonium salt .   21- Dental composition according to any one of the preceding claims wherein the photosensitizer (E) comprises in its structure one or more substituted or unsubstituted aromatic nuclei, having a residual absorption of light of between 200 and 500 nm.   22 - Dental composition according to any one of the preceding claims wherein the photosensitizer (E) is selected from the group consisting of compounds of the class of anthracenes, thioxanthones, camphorquinones, and phenanthrenequinone and mixtures thereof.   23 - Dental composition according to claim 22 wherein the photosensitizer (E) is a salt of a thioxanthone substituted with at least one group comprising an ammonium function.   24 - dental composition according to claim 23 characterized in that the associated anion of the salt of thioxanthone substituted by at least one group comprising an ammonium function is selected from the following anions: a halide, BF4, PF6; SbFb; the anion (III) of formula [BXa Rb] - defined according to claim 18, RfSO3-; (RfSO2) 3C- or (RfSO2) 2N- with Rf being a linear or branched alkyl radical substituted by at least one halogen atom, preferentially a fluorine atom.   25- Dental composition according to any one of the preceding claims wherein the photosensitizer (E), optionally in combination with at least one camphorquinone, a phenanthrenequinone and / or a substituted anthracene, has the formula: (XXV) wherein: R22 and R23 are identical or different and represent a hydrogen or an optionally substituted C 1 -C 10 alkyl radical, preferably R 22 = R 23 = methyl, - (X) being an anionic entity, preferably a halide; BF4, PF6; SbFb; the anion (III) of formula [BXa Rb] - defined according to claim 16, RfSO3-; (RfSO2) 3C- or (RfSO2) 2N-, with Rf being a linear or branched alkyl radical, substituted by at least one halogen atom, preferably a fluorine atom, and even more preferably (X) is chosen from borates of the following formulas: [B (C6H3 (CF3) 2) 4] and [B (C6F5) 4]. OH Y   26 - Dental composition according to any one of the preceding claims wherein the photosensitizer (E), optionally in combination with at least one camphorquinone, a phenanthrenequinone and / or a substituted anthracene has the formula: OH B (C6FS1M1 OH   1B (C6H3 (CF3) 2J or (PS-30) (PS-31) 27- Dental composition according to any one of the preceding claims wherein the photosensitizer (E) is selected from the group consisting of the following compounds: (PS-30): 3- (3,4-dimethyl-9-oxo-9-thioxanthen-2-yloxy) -2-hydroxypropyl) trimethyl ammonium chloride; - (PS-31): 3- (3,4-Dimethyl-9-oxo-9-thioxan-15-enen-2-yloxy) -2-hydroxypropyl) -trimethylammonium tetrakis (pentafluorophenyl) borate; - (PS-32): 3- (3,4-Dimethyl-9-oxo-9-thioxanthenyl-2-yloxy) -2-hydroxypropyl) -trimethylammonium tetrakis (bis (trifluoromethyl) phenyl) borate; - (PS-33): phenanthrenequinone; - (PS-34): camphorquinone; - (PS-35): Acenaphthenequinone; - (PS-36): dibenzoylperoxide; (PS-37): 2-ethyl-9,10-dimethoxyanthracene; (PS-38): 9,10-diethoxyanthracene; (PS-39): 9,10-dibutoxyanthracene; - (PS-40): 9-hydroxymethylanthracene; (PS-41): 2-dimethylaminothioxanthone; (PS-42): 3-ethylcarboxy-7-methoxythioxanthone; (PS-43): 1-phenyl-thio-4-propoxythioxanthone; - (PS-44): 2-methoxythioxanthone; (PS-45): 2- (N, N-diethylaminopropoxy) thioxanthone; (PS-46): 2-isopropylthioxanthone; (PS-47): 1-chloro-4-propoxythioxanthone; (PS-48): 4-isopropylthioxanthone; 0 (PS-49) (PS-50): - and mixtures thereof.   28 - Dental composition according to any one of the preceding claims wherein the photosensitizer (E) is selected from the group consisting of compounds of the family of coumarins, diketones, fluorones, aminoketones, paraaminostyrylic ketones and mixtures thereof.   29- Dental composition according to any one of the preceding claims wherein the silicone polymer (G-2) or the silicone oligomer (G-1) is combined with an organic epoxy resin or oxetane of formula (S-103) or ( S-104): o (S-103) (S-104) With: -0n <100and - D = radical chosen from linear or branched C1-C12 alkyls.   - Dental composition according to one of the preceding claims wherein the dental filler (B) is a mineral glass or a combustion silica.   31 - Dental composition according to any one of the preceding claims wherein the compound (G) is a silane (G-3) of formula: (R) b (Z) a Si E formula in which: E_ -CH2; -CH =; CH - R, identical or different, represents an alkyl, cycloalkyl, aryl, vinyl, hydrogen, alkoxy radical, preferably a C 1 -C 6 lower alkyl, Z, which is identical or different, is an organic substituent comprising at least one oxirane function; , alkenyl ether, oxetane and / or carbonate, and - a + b = 3.   32 - Dental composition according to claim 31 wherein the silane (G-3) is selected from the group consisting of the following molecules: (S-93) / si / Si (S-94) / / / si ( Dental composition according to one of the preceding claims, in which the compound (G) is an organic compound (G-4) chosen from the group consisting of the molecules (S-96) to (S-104): -96) O (S-98) O o LO O O O (S-99) O O * oo   (S-100) O 0 o (S-101) o formulas wherein: n is an integer from 1 to 10 (inclusive terminals 5); (S-103) with n <100 and D = linear or branched C1-C12 alkyl.   (S-104) with n <100 and the group D = linear or branched C1-C12 alkyl.   34 - Process for treating a reinforcing filler, in particular a dental filler, characterized in that the filler is treated: a) with at least one organosilicon coupling agent (F), and b) with at least one compound (G), said organosilicon coupling agent (F) comprising at least one reactive function (frA) directly linked to a silicon atom reacting with the dental charge and at least one reactive function (frB) not directly linked to a silicon atom reactive with a reactive function (FrC) of the compound (G).     A process for treating a reinforcing filler, particularly dental, according to claim 34 wherein: - the reactive function (frA) directly bonded to a silicon atom of the organosilicon coupling agent (F) is an alkoxy or hydroxy function ; the reactive function (frB) not directly bonded to a silicon atom of the organosilicon coupling agent (F) is an oxirane, oxetane, hydroxyl, acid, carboxylic acid anhydride or diol function; and the reactive function (frC) of the compound (G) is an oxirane, oxetane, alkenyl ether or carbonate function.   A method for treating a dental reinforcing filler according to claim 34 or 35 characterized in that the dental filler is treated by a process (I) comprising the following steps: a) the dental reinforcing filler (B) is mixed in a solvent medium and at least one organosilicon coupling agent (F) comprising at least one alkoxy and / or hydroxy function directly bonded to a silicon atom and at least one oxirane, oxetane, hydroxy and / or diol function; b) the solvent is evaporated to obtain an intermediate tooth load (B-1), c) the intermediate tooth load (B-1) undergoes a heat treatment to allow the coupling reaction between the intermediate tooth load (B-1) and the coupling agent (F) and thus to obtain an intermediate dental load (B-2), d) the intermediate dental load (B-2) is then mixed in a solvent medium with at least one compound (G) comprising at least one oxirane function, oxetane alkeny the ether and / or carbonate, e) the solvent is evaporated to obtain an intermediate dental charge (B-3), and f) the intermediate dental charge (B-3) undergoes a heat treatment so as to allow the reaction between the load Intermediate dental (B-3) and compound (G) and thereby obtain a treated dental load (B-4).   37 - A method for treating a dental reinforcing filler according to claim 36 wherein the heat treatment of steps c) and f) of the process (I) is carried out by heating to a temperature of less than or equal to 200 C, preferably lower or equal to 160 C and even more preferably between 100 and 165 C.   38. A method for treating a dental reinforcing filler according to any one of claims 34 to 37 wherein the organosilicon coupling agent (F) is defined according to claim 7 or 8.   39. A method for treating a dental reinforcing filler according to any one of claims 34 to 36 wherein the compound (G) is defined according to any one of claims 10 to 12.   A method for treating a dental reinforcing filler according to any one of claims 34 to 39 wherein the reinforcing filler is a mineral glass or a fumed silica.   41 - Reinforcing charge obtained by the process according to any one of claims 34 to 40.   42 - Use of a dental composition according to any one of claims 1 to 29, for the realization of dental prostheses or for dental restoration.   43- Dental prosthesis obtainable by crosslinking a composition according to any one of claims 1 to 33.   44 - Dental restoration material obtainable by crosslinking a composition according to any one of claims 1 to 33.