RU2509551C2 - Dental polymer compound with high dental tissue adhesion - Google Patents

Abstract

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to dentistry, namely to developing dental materials, and can be used as a filling material for the reconstruction and restoration of the anatomic shape of a tooth. A dental polymer compound comprises a carboxyl-containing methacrylate derivative of aryloxycyclophosphazene of general formula:

wherein Ar is para-, metha- or orthophenylene, n is an integer of 3 to 8, bis-phenolglycidyl methacrylate (Bis-GMA), triethylene glycol dimethacrylate (TGM), ionol, camphorquinone, 4-ethyldimethylaminobenzoate, aerosol and powdered glass filler in certain proportions.

EFFECT: compound is storage stable, has high strength characteristics along with high metal and dental tissue adhesion by using the above carboxyl methacrylate cyclophosphazene derivative as an ingredient of the compound.

3 cl, 1 tbl, 2 ex

Description

The present invention relates to dental polymeric materials and can be used to restore and restore the anatomical shape of the tooth.

Composite dental materials are known (US patent No. 4579880 from 08/01/1986, RF patent No. 2375039 from 01/30/2008 taken as a prototype), which include polymerization-capable methacrylate oligomers, for example, [2,2-bis- (3-methacryloyloxy) -2-hydroxypropoxy-4-phenyl)] propane (Bis-GMA), triethylene glycol dimethacrylate (THM), polymerization activators, fillers, for example, silanized silica powder, inhibitors (ionol) and polymerization-capable phosphazene oligomers containing atom of forcephore organic radicals with individuality copolymerizable methacrylate groups (Example № 1).

Obtained by the prototype compositions have increased compressive and bending strength, low water solubility and high water resistance, sufficient microhardness, but in some cases insufficient adhesion to metals and tissues of the tooth.

The problem to which the invention is directed is to increase adhesion to the above substrates, which can be increased by introducing acid P-OH groups into the phosphazene modifier, however, such modifications turn out to be unstable, easily undergoing phosphazene-phosphazane rearrangement:

leading to subsequent degradation of the phosphazene cycle with a decrease in the stability of the composition and the deterioration of its properties.

On the other hand, in US patents 5218070 and 6114408, adhesion to tooth tissues and metals was improved by incorporating, in the dental material, respectively polymerization unsaturated derivatives of butane of the general formula (ROOC) x − C ₄ H ₆ - (COOR ′) y, where R − H or a radical containing various acrylate groups, or a reaction product of glycerol dimethacrylate with pyromelitic dianhydride, which also includes carboxyl groups.

To increase the adhesion of modifying phosphazene and the entire composition to tooth tissues and metals, the applicants used carboxyl-containing phosphazene modifiers (example 2) synthesized according to the scheme:

where Ar are aromatic radicals, more often ortho-, meta- and parophenylene, n≥3.

This reaction proceeds under relatively mild conditions and allows the ratio of the starting materials to be widely controlled in the resulting modifiers of the content of carboxyl and methacrylate groups determined by classical methods (by the value of acid and bromine numbers) or by laser mass spectra. So, at a molar ratio of P ₃ N ₃ (OC ₆ H ₄ COOH) ₆ : glycidyl methacrylate equal to 1: 3, the final reaction mixture includes products containing from 1 to 5 methacrylate groups with a predominance of trisubstituted compounds.

For the synthesis of the starting carboxylphosphazenes, hexachlorocyclotriphosphazene or mixtures thereof with the higher chlorocyclophosphazenes — octamer, hexamer, and others — were used; these chlorophosphazenes are reacted with phenolates of hydroxide aldehydes and converted to the corresponding formylaryloxycyclophosphazenes and then oxidized to the carboxyl-containing aryloxycyclophosphazenes for the reaction with glycidyl methacrylate.

The novelty of the proposed composition is that:

- the above formula of the phosphazene modifier simultaneously contains two types of functional groups - methacrylic and carboxyl; the former provide copolymerization with the main binders (a mixture of Bis-GMA and TGM) and increase the density of the resulting spatial network, the latter, due to interaction with calcium hydroxyappatite atoms, increase the adhesion of the composition to tooth tissues;

- these new compounds not previously described are obtained by the interaction of carboxylcyclophosphazenes with glycidyl methacrylate with the possibility of varying within the necessary limits the ratio of functional carboxyl and methacrylate groups;

- a mixture of bisphenol glycidyl methacrylate (Bis-GMA) and triethylene glycol dimethacrylate (THM) is used as the polymerization-capable methacrylate oligomers. Selected methacrylate oligomers in combination with carboxyl-containing methacrylic derivatives of aryloxycyclophosphazenes provide strong, chemically stable spatially cross-linked polymer structures;

- as the polymerization activators, a photoinitiating system is used, for example, camphoroquinone and 4-ethyl dimethylaminobenzoate, which allows polymerization of the composition with blue light at a wavelength of 450-500 nm for 20-40 seconds. The components that make up the photoinitiating system are well compatible and stable during storage;

- fillers use mixtures of highly dispersed silanized inorganic fillers based on oxides of silicon, aluminum, barium, magnesium, or others, for example, aerosil (particle size 7-40 nm) and silanized barium glass filler (particle size 0.4-5.0 μm). The combination of fillers with different particle sizes allows for dense "packing" of particles in an oligomeric matrix, a high level of filling of the composition, and hence high physical and mechanical properties;

- the composition of the proposed dental polymer composition of these components are in the following ratios (wt.%):

Bisphenol Glycidyl Methacrylate (Bis-GMA) 7-18 Triethylene glycol dimethacrylate (THM) 5-13 Methacrylic carboxyl-containing derivative of aryloxycyclophosphazene 5-10 Ionol 0.001-0.005 Camphoroquinone 0.05-0.5 4-ethyldimethylaminobenzoate 0.05-0.5 Aerosil 0.5-10 Powdered Glass Filler the rest is up to 100

Compliance with the criterion of "inventive step" is confirmed by the following features:

- as the polymerization-capable phosphazene compounds, new carboxyl-containing methacrylic derivatives of aryloxycyclophosphazenes of the formula are used:

in which Ar is an aromatic radical, mainly ortho-, meta- or paraphenylene, and n is an integer from 3 to 8;

- carboxyl-containing methacrylic aryloxycyclophosphazenes are prepared by reacting the corresponding carboxylaryloxycyclophosphazenes P _n N _n (OArCOOH) _2n with glycidyl methacrylate and, in contrast to the prototype methacryloxyphosphazene oligomers, the compounds of the present invention have a lower molecular weight, are easily combined with combined with fillers, forming a more homogeneous composition during UV curing.

Preparation of a dental polymer composition

Example 1

In a vacuum homogenizer prepare a composition of the following composition (g):

Bisphenol Glycidyl Methacrylate (Bis-GMA) 12.6 Triethylene glycol dimethacrylate (THM) 8.4 Methacrylic derivative of polyaryloxyphosphazene 3.75 Ionol 0.005 Camphoroquinone 0.125 4-ethyldimethylaminobenzoate 0.125 Aerosil OX-50 (average particle size 40 nm) 2.0 Barium glass filler SCHOTT-8235 (average particle size 0.7 μm) 73

Obtained in the form of a paste, the dental polymer composition is placed in a sample preparation mold, irradiated for 40 seconds with light at a wavelength of 400 - 500 nm using an apparatus for light curing of dental materials. Cured samples of the dental polymer composition are immersed in distilled water and incubated in a thermostat at a temperature of 37 ± 2 ° C for 24 hours. At the end of the exposure of the samples under these conditions, they are subjected to tests according to the methods of GOST R 51202-98.

Example 2

In a vacuum homogenizer prepare a composition of the following composition (g):

Bisphenol Glycidyl Methacrylate (Bis-GMA) 12.6 Triethylene glycol dimethacrylate (THM) 8.4 Carboxyl-containing methacrylic derivative of aryloxycyclotriphosphazene with an acid number of 150 mg KOH / g and a bromine number of 49 g Br / 100 g 5,0 Ionol 0.005 Camphoroquinone 0.125 4-ethyldimethylaminobenzoate 0.125 Aerosil OX-50 (average particle size 40 nm) 2.0 Barium glass filler SCHOTT-8235 (average particle size 0.7 μm) 3

Obtained in the form of a paste, the dental polymer composition is placed in a sample preparation mold, irradiated for 40 seconds with light at a wavelength of 400 - 500 nm using an apparatus for light curing of dental materials. Cured samples of the dental polymer composition are immersed in distilled water and incubated in a thermostat at a temperature of 37 ± 2 ° C for 24 hours. At the end of the exposure of the samples under these conditions, they are subjected to tests according to the methods of GOST R 51202-98.

Polymerization-capable carboxyl-containing methacrylic derivatives of aryloxycyclophosphazenes on the example of hexachlorocyclotriphosphazene were obtained according to the scheme:

where R is CH ₂ OC (O) C (CH ₃ ) = CH ₂

To a solution of hydroxybenzaldehyde in ethyl alcohol, a separately prepared alcoholic solution of sodium ethoxide, taken in stoichiometric ratio to the aldehyde, is poured. The reaction is carried out for 10 minutes, after which ethanol is distilled off on a vacuum rotary evaporator.

To a suspension of hydroxyaldehyde phenolate in tetrahydrofuran (THF), a solution of hexachlorocyclotriphosphazene (HCF) in THF in a molar ratio of phenolate: HCF = 8: 1 is poured with stirring. The reaction mixture is boiled for 9 hours, after which it is cooled, filtered off from the precipitate formed and THF is distilled off on a rotary evaporator. The resulting formylphenoxycyclotriphosphazenes are boiled in chloroform, filtered off, chloroform is partially distilled off, ethanol is added to the resulting concentrated solution and left in air until product crystals form.

The formed formylphenoxycyclotriphosphazenes by oxidation with potassium permanganate in an alkaline medium for 30 hours are transferred to carboxylphenoxycyclotriphosphazenes, which are precipitated with concentrated hydrochloric acid.

To synthesize methacrylic carboxyl-containing derivatives of aryloxycyclophosphazenes, the required amount of glycidyl methacrylate is added to a solution of carboxylphenoxycyclotriphosphazene in dimethyl sulfoxide and the reaction is stirred at 100 ° C for 24 hours, the reaction mixture is precipitated in isopropyl alcohol and the precipitate is dried in vacuum. The resulting products are characterized by the presence of ³¹ P NMR signals in the region of 6-10 ppm. (hexazubstituted triphosphazene rings), and ¹ H NMR in the region of 5-7 ppm, corresponding to double bond protons, and chemical shifts in the region of 3-5 ppm characteristic of the epoxy ring uncovered as a result of attachment. According to the laser mass spectrum (MALDI-TOF), synthesized methacrylic carboxyl-containing phosphazenes contain compounds with 1-5 attached GMA residues per phosphazene molecule. Acid and bromine numbers are 150 mg KOH / g and 49 g Br / 100 g, respectively.

Tests of samples of the dental polymer composition of the claimed composition showed that the developed material has increased strength and adhesive characteristics and exhibits stability during storage (table 1).

Table 1 - Physico-mechanical characteristics of modified filled polymer compositions based on Bis-GMA / TGM-3 (3/2)

Modifier Number of modi-fixture, mass. % of binder Physicochemical Characteristics Adhesion, MPa Destructive stress, MPa to tooth tissues to metal under compression when bending Requirements GOST R 51202-98 not less than 7 not less than 5 not less than 170 not less than 50 absent 0 2.5 ± 0.1 1.7 ± 0.1 290.0 ± 5.2 96.4 ± 2.8 Prototype 3.75 not installed not installed 430 140 Carboxyl-containing methacrylic derivative of aryloxycyclo-phosphazene 3 6.5 ± 0.2 6.3 ± 0.1 310.0 ± 4.2 105.1 ± 2.5 5 10.8 ± 0.1 7.0 ± 0.2 320.0 ± 4.0 110.0 ± 3.0 7 14.8 ± 0.2 8.6 ± 0.1 330.0 ± 3.5 112.4 ± 2.6 10 18.9 ± 0.3 9.8 ± 0.2 329.0 ± 4.1 113.4 ± 3.5

Claims (3)

1. Dental polymer composition containing polymerization-capable methacrylate oligomers, polymerization activators, inhibitors, fillers and polymerization-phosphazene compounds, characterized in that carboxyl-containing methacrylic derivatives of cyclophosphazenes of the general formula are used as polymerization-phosphazene compounds:

in which Ar is para-, meta or ortho-phenylene, n is an integer from 3 to 8, while the polymer composition contains, wt.%:
Bisphenol Glycidyl Methacrylate (Bis-GMA) 7-18 Triethylene glycol dimethacrylate (THM) 5-13 Carboxyl-containing methacrylic derivative of aryloxycyclophosphazene 5-10 Ionol 0.001-0.005 Camphoroquinone 0.05-0.5 4-ethyldimethylaminobenzoate 0.05-0.5 Aerosil 0.5-10 Powdered Glass Filler up to 100 2. The dental polymer composition according to claim 1, characterized in that the mixture of [2,2-bis- (3-methacryloyloxy-2-hydroxypropoxy-4-phenyl)] propane (Bis-GMA), triethylene glycol dimethacrylate acts as the polymerization-capable methacrylate oligomers (THM) and a carboxyl-containing methacrylate cyclophosphazene derivative, the polymerization activator is the photoinitiating system camphoquinone + 4-ethyl dimethylaminobenzoate, the inhibitor is ionol, and the filler is a mixture of aerosil and barium glass powder with different sizes of tea stits. 3. The dental polymer composition according to claim 1, characterized in that the carboxyl-containing methacrylic phosphazene compounds are prepared by reacting the aryloxycyclophosphazenes P _n N _n (OArCOOH) _2n with glycidyl methacrylate.