NO165222B - MASS FOR PREPARATION OF PLASTIC HV. HARD LOTS FOR DENTAL TECHNIQUES, HV. (DENT) MEDICAL PURPOSES, PROCEDURES FOR PREPARING THEREOF AND USING THEREOF. - Google Patents

Abstract

1. Claims for the Contracting States : BE CH DE FR GB IT LI LU NL SE Composition for the preparation of plastic or hard materials for dental technical, (dental) medical and related purposes, which includes a thermoplastic material and ordinary additives, characterised in that the said composition also contains 0.05 to 10 wt.% jojoba oil. 1. Claims for the Contracting State : AT Process for the production of a preparation for plastic or hard compositions for dental technical, (dental) medical and related purposes, which includes a thermoplastic material and ordinary additives, characterised in that the said composition also contains 0.05 to 10 wt.% jojoba oil.

Description

The invention relates to a mass for the production of plastic or hard masses for dental technology, respectively (dental)-medicine-

purpose, comprising a thermoplastic polymer which before polymerization consists of a mixture of monomers and polymers, or mixed polymers, of acrylic and methacrylic acid esters, common hardeners and accelerators, metal soap and/or silicate, crosslinking agent and common fillers, method of production thereof and use thereof.

Use of acrylic or methacrylic acid esters for (dental) medical and technical purposes, especially for taking jaw impressions and for placing plastic dental prostheses etc. -

are known. It is also known for this purpose to acryl-

or methacrylic acid ester to make additions, such as plasters of other types, cellulose derivatives, (natural) - resins (such as copal, sandarac), paraffin, wax, oil, dyes and fillers. In West German published patent application 2718017, the addition of metal soap and/or metal silicate to such plastic or hard masses for dental technical and (dental) medical purposes described.

Acrylic or methacrylic acid esters are usually an-

reversed by dissolving a powder, bead or splinter granulate of a polymer or mixed polymer of these compounds in a liquid monomer, and by this solution possibly hardening with the addition of promoters.

When such mixtures are used, however, certain

cons.

While the dissolution of the powder in the liquid is relatively time-consuming, parts of the polymer remain undissolved in the powder-liquid system during cold polymerization, and this affects the stability and homogeneity of the material. It is there-

for it is desirable to provide a mass which ensures easier workability, possibly on the basis of an improved viscosity and plasticity for the material.

The cold polymers which are based on monomeric methyl methacrylate are also considered to be hostile to mucous membranes. Also

in this regard, it is desirable to provide a pre-

improved dental pulp to avoid resp. reduce this disadvantage. IN

in addition, burns etc. can occur in the mouth due to the rapid depolymerization of cold polymers. When producing underlinings from monomeric methyl methacrylate, the products formed do not always have a perfectly smooth surface,

and for this reason they are partly saliva absorbent and partly susceptible to attack by the oral microflora.

The invention therefore aims to provide a mass of the above-mentioned type, which due to its improved viscosity ensures easier and faster processing, exhibits an improved mechanical strength and

exerts a healing effect on pressure points and inflammations in the mouth area as well as in connection with joint prostheses,

forms smooth surfaces, is odorless and tasteless and well

equally with mucous membranes, and maintains an optimal adaptation accuracy for a longer time. If necessary, the mass should be easily left

be regulated by minor changes to the composition while achieving the desired consistency, e.g. hard or

elastic or permanently soft.

The above-mentioned task is solved according to the invention, which provides a mass of the above-mentioned type, and the mass is characterized by the fact that, in addition to a thermoplastic polymer, which before polymerization consists of a mixture of monomers and polymers, respectively mixed polymers, of acrylic and methacrylic acid esters, common curing agents and accelerators, metal soap and/or silicate, crosslinking agent and common fillers, comprise 0.05-10% by weight of jojoba oil.

Jojoba oil used in the mass is the oil that

is obtained from the jojoba plant belonging to the family Buxaceae, and has been purified:. In addition, the term "jojoba oil" shall i

the sense in which this designation is used here also includes j oj obavoks.

It is preferred that jojoba oil is used in a concentrated

tion of 0.1-5% by weight together with the other components for the manufacture: of plastic or hard masses.

Due to the addition of jojoba oil to the mass for the production of plastic or hard masses, it is possible to prepare the workability, toughness, hardness and firmness, as well as the surface properties and durability in the mouth

(no signs of ageing) as well as brittleness, odor formation and unappealing color formation, as the masses exert a healing effect on pressure points and inflammations in the mouth area as well as for joint prostheses, and it is also possible to achieve non-porous, non-brittle and non-shrinking masses that are also especially well compatible with mucous membranes which is excellently suitable for a wide variety of (dental) medical and dental technical and other purposes. With the help of the masses, it was particularly successful, depending on the desire, to obtain elastic, permanently soft or hard impression materials or underlinings, as hardness or elasticity can be adjusted as desired. The present pulp stands out in particular in that a dental technical or

(dental) medical pulp of any desired plasticity or hardness can be achieved, as the pulp retains its optimal adaptation accuracy and viscosity or plasticity in the mouth for a longer period of time, exerts a healing effect on pressure points and inflammations in the mouth area and also in connection with joint prostheses and exhibits good mucous membrane compatibility.

As resolution or dispersant for homo-,

co- respectively the mixed polymer part, the methyl ester of acrylic and/or methacrylic acid can be used as well as in hot polymerization of acrylates without methyl ester addition. This embodiment comes into particular consideration in such an application where the aim is to carry out a hot polymerization or where polymerization in the patient's mouth does not take place. A particularly preferred mass, however, exhibits

time no significant or, particularly advantageously, no proportion of monomeric acrylic acid or methacrylic acid methyl esters, but instead of these, high-boiling ester derivatives of the aforementioned acids are used. In particular, a content of at least one monomeric acrylic and/or methacrylic acid ester with 6-10 carbon atoms is taken into account. Examples of these are 2,3-epoxypropyl-,

n- respectively tart. butyl-, n- or cyclohexyl methacrylic acid esters or mixtures of these monomers. Likewise, the analogous esters of acrylic acid come into consideration, and it can then be particularly advantageous to use mixtures of the aforementioned

monomeric acrylic acid esters and methacrylic acid esters. Although it is preferred to use ester derivatives with a total number of 6-10 carbon atoms, however, at least partially ester derivatives of acrylic or Methacrylic acid is used with a total of 11 carbon atoms under or above the range of 6-10 carbon atoms indicated as advantageous, e.g. methacrylic acid dodecyl ester, methacrylic acid triethylene glycol monoethyl ester or methacrylic acid ethylhexyl ester etc. Finally out-

makes a reaction product of glycidyl methacrylate and bxs-

phenol A a particularly advantageous momomer..

The polymers can in principle consist of: polyacrylates

and -methacrylates respectively. mixture©:— and/or copolymers thereof. In addition, certain proportions of plaster of another type, e.g. polyvinyl chloride, polyvinyl acetate or polyvinyl alcohol,■ be present. A mixture of medium molecular weight polymethacrylates is preferred. Among these are again those: particularly advantageous which exhibit good solubility properties in the monomer proportions used and in the solvent proportions that are partly contained therein. Such polymethyl methacrylate mixtures with medium molecular

weight such as are soluble in esters, ketones, chlorinated aliphatic hydrocarbons or cyclic esters etc, and exhibit thermoplastic properties, are available on the market.

A mixture of monomers and polymers or mixed polymers of acrylic and methacrylic acid esters thus constitute the thermoplastic material before polymerization. This mixture is preferably in the form of a mixture or paste. r-.

The polymer content in the monomer solution, which may contain additives, can vary within wide ranges. Generally, polymer proportions will be present in an amount of 10-70% by weight, based on the total material. A particularly preferred range for the weight fractions of the polymer is 10-40%,

based on the sanded mass, as this results in particularly light-flowing to paste-like and dough-like masses which can be molded, sprayed, distributed with a spatula or can be pressed out of pressure vessels - in the form of liquid, dough-like or paste-like mass and distribute.

Metal soaps and/or silicates, a catalyst and possibly a curing accelerator are added to the solutions or syrups, pastes or dough-like masses of polymers or mixed polymers in the monomer mixtures.

As metal soaps, stearates, laurates, oxystearates, palmitates, montanates, oleates or ricinusoleates of metals, such as e.g. aluminium, magnesium or calcium, proved suitable. The alkaline earth soaps are preferred, and these metal soaps must be present in a finely divided state. It is particularly preferred to use magnesium stearate and calcium stearate. The amount of added metal soap or soaps respectively mixtures thereof advantageously amount to 0.1-10% by weight, calculated on the total mass.

As silicates which have also proved advantageous to use, primarily alkali silicates come into consideration, especially commonly marketed, soluble water glass compounds, as both sodium and potassium silicates or other mixed alkali silicates can be used. Alkali aluminum silicate Br is particularly suitable. The addition amount of such a silicate preferably amounts to 1.5-5%, calculated on the total mass. For such water glass preparations, the so-called oil number must not exceed 26, and an oil number of approx. 22 has proven to be particularly beneficial.

If the plastic or hard pulps for dental technical or dental medical purposes will be exposed to particularly strong stress, it may be beneficial for the pulps to contain a proportion of a cross-linking agent. Among the materials that effect cross-linking of methylacryl or acrylate are olefinic dimethyl acrylates, such as ethylene dimethacrylate , propylene dimethacrylate or polyethylene glycol dimethacrylate, are particularly suitable. It is then advantageous that the polyethylene glycol dimethacrylate crosslinking agents used, if any, have a relatively low molecular weight. The crosslinking agent, which is particularly suitable for preventing the later occurrence of stress cracks, can be used, for example, in an amount of 0.1-1.0% by weight, based on the total mass.

However, the cross-linking agent can also be used in

higher amounts and partially replace the monomeric (meth)acrylate.

According to one embodiment which may be considered special

preferred for certain applications, the monomer portion is even completely replaced by a monomeric cross-linking agent. In the latter case, therefore, the polymer portion must exclusively be dissolved in the monomeric crosslinking agent.

According to a preferred embodiment, the present mass for the production of plastic or hard masses for dental technical and (dental) medical purposes of a two-component system, particularly preferred of a powder system and a liquid system, the powder system comprising the polymer plastic and possibly the metal soap, fillers and peroxide (catalyst), while the liquid system comprises the monomeric acrylate, the plasticizer, the accelerator as well as jojoba oil.

In order to increase the durability of the mass, a small amount of stabilizers or inhibitors can be added to these to prevent an unintentional further polymerization of the solution when it is stored. For this purpose, e.g. phenolic compounds, such as aminophenols, dibutyl-methylphenol or butylhydroxyanisole, or also hydroquinone, pyrogallol or fuel catechin in consideration. These inhibiting substances can be added in an amount of 2-100 ppm of the mass.

Methacrylates usually have a typical bitter aftertaste that is transient, e.g. when adapting the (functional) impression spoon that is provided with the impression material, or when adapting the undercarriage for a prosthesis, can have a disturbing effect. To overcome this, it is also beneficial to add carbohydrate-free sweeteners to the mass, such as cyclamates, or carbohydrate-based anticariogenic sugar additives, e.g. xylitol. A commonly marketed mixture of sodium cyclamate with 10% saccharin has been found to be particularly beneficial. In addition, the solutions may contain the usual pigment additives.

The catalyst used for curing the plastic mass can in principle be added in powder form. However, it is preferably added in the form of a solution in a solvent which should preferably be easily soluble, as the catalyst can in this way be easily and evenly distributed in the acrylate solution. As catalysts or initiators, peroxides known per se, such as hydrogen peroxide, tert. butyl hydroperoxide, cumene hydroperoxide, dialkyl or diaryl peroxides, ketone peroxides, diacyl peroxides, such as dibenzoyl peroxide, or peroxy acids, azo compounds, such as azo-diisobutyric nitrile or azodicarbonamide, which are optionally used dissolved in solvents, such as dibutyl phthalate, methanol, acetic ester , acetone or methyl ethyl ketone.

For catalyst systems that are self-curing/ i.e.

which without further application of heat should cause hardening, for the actual catalyst or initiator an accelerator or activator is also used which causes the decomposition of the initiator and thus the start of the polymerization of the monomer into polymers. As such accelerators have tert. amines, alkyl, alkylaryl or oxyalkylamines and also reducing agents, such as sulfinic acids or dithionites, have proven suitable, and these can be added in an amount of 1-3%. Instead of the specified catalyst systems, all other systems can of course also be used which are applicable for the polymerization of acrylates or methacrylates. As an accelerator, e.g. p-tolueneamine in speech in an amount of 0.5-2%. The accelerator is found in the present masses preferably in the syrup or in the paste or in the liquid itself. However, the curing can also be achieved in the absence of an accelerator, e.g. when exposed to UV radiation. In the case of hot polymerization, curing is obtained by applying heat without the use of an accelerator.

The masses are preferably prepared in such a way that immediately before the mass is used it is mixed in a two-component system consisting of a powder system comprising the polymer, optionally fillers and metal soaps, and catalyst, and a liquid system consisting of the monomeric acrylate and optionally comprising a plasticizer , accelerator and the jojoba oil used according to the invention.

When the present masses are used, the mass is e.g. for the underlining of a prosthesis applied to the surface of the prosthesis which has been previously roughened, advantageously slightly dissolved with a solvent, and introduced into the patient's mouth where the mass polymerizes completely within a few minutes and under pressure and possibly with the exclusion of air. When dentures are repaired, it is advantageous e.g. that the applied mass according to the invention is covered with glass or cellophane paper because curing should best take place under the exclusion of air.

When the pulp is used in (dental) medicine or the dental technique, the great advantage is obtained that the finished polyacrylic solution can be brought to solidify in the shortest possible time simply by adding a catalyst solution, preferably in the form of a two-component system of a powder system and a liquid system, and on this way, an optimal fitting accuracy and impression can be achieved with the help of impression or the underlining material without the material shrinking or changing during this time. If desired, elastic, permanently soft or hard tooth masses can then be achieved, and the finished polymerization can take place completely in the patient's mouth without burns, etching or irritation of the mucous membrane occurring even with cold polymerization.

The pulps are above all suitable for dental purposes, such as e.g. for the production of an individually adapted functional impression spoon with the corresponding design for the production of a dental prosthesis, as forming material and underlining material in the production of dental guards, especially for sportsmen, as described in the patent applicant's parallel West German patent application submitted on 19 October 1983, as impression massages in general or for underlays and repairs of dentures.

A particular advantage of the use of the present masses consists in that, due to the fact that these are easy to handle, they are

suitable for self-help, e.g. for wearers of partial or total dentures, for cosmetic corrections by self-help, e.g. for corrections of smile lines in denture wearers.

The present mass as well as the method for producing it and its use are described in more detail in the examples below.

Example 1

25 parts by weight of a copolymer consisting of 96 parts by weight methyl methacrylate and 4 parts by weight ethyl acrylate are mixed in a mixing container with 75 parts by weight acrylic cyclohexyl ester to which 1% p-tolueneamine and 2% 1,4-butanediol dimethacrylate have been added. Instead of the cycloalkyl ester, 65 parts by weight of a mixture of methacrylic acid-tert. butyl ester and methacrylic acid methyl ester in a ratio of 1:1 or 1:2 is used. 2% is added to the syrup obtained

of a commonly marketed alkali aluminum silicate, 2.5% magnesium stearate and also 1% jojoba oil.

In use, a solution of 5 parts by weight of benzoyl peroxide in 25 parts by weight of dibutyl phthalate is added to this mixture from a dropper bottle. After a short time, the mass begins to become viscous so that it can now be applied to the previously prepared prosthesis and introduced into the patient's mouth. After a few minutes, the mass solidifies in the mouth into a hard lining.

Example, 2

50 parts of a mixed polymer consisting of 96 parts by weight of methyl methacrylate and 4 parts by weight of ethyl acrylate are dissolved in a mixture of 50 parts of methacrylic acid tert-butyl ester, methacrylic acid methyl ester and methacrylic acid n-hexyl ester which are mixed in the ratio 1:1:1 . 3% magnesium stearate and 1% of a commonly marketed alkali aluminum silicate, 1% p-tolueneamine and also 1% jojoba oil are added to this mixture. In the same way as according to example 1, a benzoyl peroxide solution is added drop by drop to the mass for processing it, and within a short time a viscous mass is obtained which can be easily distributed on the prosthesis and after a short time provides an elastic underlining which exhibits an excellent fitting form, is permanent and practically does not show shrinkage.

Example 3

Below is described the manufacture of a dental guard for athletes, where a functional impression spoon, as described in West German published patent application 2718017, is used. This functional spoon, which consists of a thermoplastic material, is softened by immersion in warm water at a temperature of 70°C, and is individually adapted to the tooth and jaw situation by applying light pressure.

Then a molding material/underlining material consisting of 40% by weight polyacrylate, approx. 55% by weight of methacrylic acid hexyl ester, 1% by weight of calcium stearate and 1% by weight of jojoba oil together with common hardeners and accelerators, filled in the functional impression spoon, and this in turn is adapted to the dental and jaw conditions in the mouth. The above-mentioned molding material/underlining material was prepared from a two-component system which was mixed with each other immediately before it was used. After approx. 10 minutes, the elastic molding material/underlining material has fully polymerized and forms a soft buffer zone between the relatively hard material for the spoon and the teeth. is subjected to light pressure, part of the molding material/underlining material penetrates through the recesses, polymerizes in this place and further forms a soft buffer zone between the lower and upper row of teeth.

In the same way, the above-described material in the form of a molding material that has been filled in a functional impression tray that has already been preliminarily adapted to the patient's jaw situation can serve to achieve a more accurate, better model-compliant and non-shrinking impression. It is a particular advantage that when a functional impression spoon made of acrylate plastic is used together with a molding material that is built up on the basis of the acrylate, it is not necessary to use an adhesive, which is otherwise necessary in connection with the usual commercially available molding materials. Thereby, an improved functional footprint can occur or an improved situation impression for the production of a prosthesis or partial dentures are made in a simple way, as in particular more accurate fitting prostheses that fit better can be made.

Claims (15)

1. Mass for the production of plastic or hard masses for dental technology or (dental) medical purposes, comprising a thermoplastic polymer which before polymerization consists of a mixture of monomers and polymers, respectively mixed polymers, of acrylic and methacrylic acid esters, common hardeners and accelerators, metal soap and/or silicate, crosslinking agent and common fillers, ■ characterized \v e d-., ■ .at. the mass" in •addition bm--contains 0.05 - 10% by weight jojoba oil.... ' Y 2. Mass according to claim 1, characterized in that it contains 0.1-5% by weight of jojoba oil. 3. Mass according to claim 1, characterized in that the thermoplastic polymer comprises monomeric and/or polymeric methyl methacrylate. 4. Mass according to claim 1, characterized in that the thermoplastic polymer comprises an acrylic or methacrylic ester with a total of 6-10 carbon atoms or a mixture thereof. 5. Mass according to claim 4, characterized in that the ester is a hexyl ester. 6. Mass according to claim 1, characterized in that the acrylate plastic essentially does not comprise methyl methacrylate. 7. Mass according to claim 1, characterized in that the thermoplastic polymer before the finished polymerization consists of a solution or a paste of a polymer or polymers or mixed polymers in a monomer acrylic and/or methacrylic acid ester. 8. Mass according to claim 7, characterized in that the total proportion of the polymer is 10-40%, based on the total mass. 9. Mass according to claim 1, characterized in that it contains 0.1 - 10% by weight of metal soap and/or 1.5 - 10% by weight of silicate. 10. Mass according to requirement 9 t characterized in that the metal soap consists of calcium stearate and/or magnesium stearate. 11. Mass according to claims 1-10, characterized in that it consists of a powder system and a liquid system, the powder system comprising the polymer resin and possibly the metal soap, fillers and catalyst, while the liquid system comprises the monomeric acrylate, the plasticiser, the accelerator and the jojoba oil. 12. Method for producing a mass according to claims 1-11, characterized in that a two-component system which consists of a powder system that includes the polymer, possibly fillers, metal soaps and catalyst, and a liquid system that consists of the monomeric acrylate that possibly contains plasticizer and accelerator, and jojoba oil, are mixed together. 13- Use of the mass according to claims 1-11 for the production of dental technical and (dental) medical forming and lining materials. 14. Use according to claim 13. for the production of underlinings for joint prostheses. 15. Use according to claim 13 as molding material for the production of a dental guard, especially for sportsmen, as well as in the production of an individually adapted (functional) impression tray.