JPS63290559A - Composite implant - Google Patents

Abstract

PURPOSE:To obtain an embedded type dental composite implant wherein an outer layer and an internal metal substrate are strongly fixed, by bonding the calcium phosphate of the outer layer to the internal metal substrate by a (meth) acrylic polymer having an acidic group. CONSTITUTION:An outer layer 1 composed of calcium phosphate such as calcium hydroxyapatite having a bottomed tubular structure and the metal substrate 2 present in the outer layer and formed into a hollow structure having the same bottom part as the outer layer 1 are prepared and subsequently bonded by an adhesive 3 containing a (meth)acrylic monomer having an acidic group represented by formula I capable of lowering the pH of water to 5 or less or having a (meth)acrylic polymer having an acidic group dissolved therein. Said adhesive is polymerized and cured by a BPO-amine type polymerization initiator to form a polymer layer. By this method, a composite implant wherein the calcium phosphate layer and the metal substrate are strongly unified is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a composite implant for living bodies, and particularly to a dental implant that is implanted into alveolar bone for mounting an artificial tooth crown.

(Prior Art) Some typical dental implants as composite implants have already been put into practical use. For example, there are devices made of alumina or titanium, which are inert to living organisms, and processed into various shapes that can be implanted into the jawbone, such as a screw-in type. There are also types that are made of calcium hydroxyapatite ceramics, which have high biocompatibility, and are implanted by direct attachment to the bone. However, all of these dental implants have the following problems. That is, the former is held within the jawbone only by mechanical force and tends to fall off when used for a long period of time. In addition, the latter type of dental implant has the property of attaching to the bone as described above, but since the abutment part protrudes into the oral cavity after implantation, it is difficult to maintain a resting state, causing oscillation and causing the attachment to the bone. is inhibited, and is likely to fall out like the dental implants mentioned above. However, as an improved version of the above-mentioned dental implant, a buried type dental implant has been proposed (John Earl Smith).

H, 8rnith), American Journal of Orthodontists (Am, J, 0rtbod
, ) 76, 618 (1979), JP-A-1983-t
36s4]. The medical implant consists of a hollow metal or ceramic coated with biocompatible calcium phosphate such as droxyabatite or bioactive glass. Dental implants are inserted under the mucosa within the jawbone, and after the implant and bone have completely adhered, the abutment is fused in a second surgery. For dental implants, a method has been reported in which calcium phosphate or bioactive glass and metal are bonded with glass by immersion, baking, etc. 1985)), when a dental implant bonded with glass is used for a long period of time, the glass in the adhesive layer dissolves, and the calcium phosphate or bioactive glass and metal peel off. Another method for bonding calcium phosphate and metal in dental implants is thermal spraying using plasma, etc.
3-28997, Japanese Unexamined Patent Publication No. 62-34558, etc.], adhesion using epoxy resin (Japanese Patent Publication No. 62-3121), etc. have been proposed. However, in the former case, as in the case of bonding using glass, the calcium phosphate and metal may peel off if used for a long period of time. In the latter case, the adhesive strength of the epoxy resin to calcium phosphate and metal in the body is small, making it difficult to use as a dental implant.The toxicity of the epoxy resin in the body is also a problem.

(Problems to be Solved by the Invention) Therefore, the problem to be solved by the present invention is to obtain a composite implant in which the outer layer made of calcium phosphate and the inner metal base are firmly fixed.

(Means for Solving the Problems) As a result of intensive studies by the inventors of the present invention to solve these problems, we have arrived at the present invention described below.

That is, the present invention relates to a composite implant in which an outer layer made of calcium phosphate and a metal substrate inside the outer layer are fixed by a polymer whose constituent unit is one unit of a (meth)acrylic monomer having an acidic group. Such implants are useful as buried dental implants.

It is a tubular structure with a bottom. Reference numeral 2 denotes a metal base inside the body, which, like 1, has a hollow structure with a bottom. 3 is a polymer layer for bonding 1 and 2 together, and usually has an acidic group (an adhesive containing a methanoacrylic monomer or a 7-mer solution containing a (meth)acrylic polymer having an acidic group). It is formed by curing a liquid adhesive.The buried dental implant is usually used by sealing the upper part of the metal base with a plug having a structure as shown in Fig. 3. It is an abutment on which a tooth crown can be attached, and is attached to the implant after removing the stopper shown in Fig. 2.The buried dental implant is a surgical procedure in which the jawbone is replaced with viscosity in the jawbone during the first surgery. After the implant and bone are completely attached, the plug shown in Figure 2 is removed in the second surgery, and the abutment shown in Figure 3 is attached to it.

In the buried dental implant of the present invention, the outer layer of calcium phosphate is calcium hydroxyapatite,
It is selected from sintered bodies made of orthocalcium phosphate or a mixture thereof. The material of the metal base inside the device is titanium, titanium alloy, cobalt-chloride alloy, etc.

It is preferable (but not necessary) that the inner surface of the metal base be threaded. The material of the plug inserted into the metal base is preferably the same as that of the metal base, but may be made of other metal or It may be made of other materials such as silicone rubber or plastic.The tip of the stopper does not need to be in contact with the bottom of the inner surface of the metal base (it may be shorter than that). It is preferable that the abutment is made of the same material as the metal base.If the inside of the metal base is threaded, the same protruding part of the abutment is threaded at the same pitch as in the case of the above-mentioned plug. and then use it.

Another method for attaching the abutment to the metal base is adhesion using the adhesive used in the present invention or other adhesives. It is also possible to attach using screws and the adhesive at the same time. If the inner surface of the metal base is threaded,
The stopper should be threaded and rounded to have the same pitch.

The characteristics of the present invention are that the outer layer is made of calcium phosphate and the inner layer is a metal base or a polymer having an acidic group (one unit of methane acrylic monomer is one constituent unit).

The acidic group in the polymer means that when it comes into contact with water, the p
means a functional group that can reduce R to 5 or less, -coo
Also includes acid halogen groups such as n group, -P-011 group (-P-Oil group), IOR (JHOil OR -C-X (where X represents F, C4%Br or ■) group) Among the above-mentioned acidic groups, the -P-Of-1 group is particularly preferable.The seven-piece unit having such an acidic H group is 10 H (where B1 represents H or OHa). a represents a (m+13-valent organic group having 2 to 40 carbon atoms; Yl);

Yl is O%S or? tHb (Bb represents H or an alkyl group having 1 to 4 carbon atoms), m is an integer of 1 to 4, k
represents 0 or 18. ] A polymer containing one monomer unit coated with has excellent adhesive strength. Especially when water resistance is required for adhesive strength, B
It is preferable that it is an organic residue having a valence of 4 to 40 (m+1).

In the present invention, the polymer layer that fixes the calcium phosphate outer layer and the metal substrate is formed by polymerizing and curing an adhesive containing a (meth)acrylate monomer having an acidic group, as described above. The outer layer and the metal substrate are secured.

Specific examples of nanatsumer include the following compounds.

(1) Monomer H having -P-011 group (1(JH (n is an integer of 2 to 40)
~40 integer] OH 1 recommendation ki2C= 0-LXJL)CJi2CH(!120Q
C-C=QE120PO((1)2 (21-P -OR group-containing seven-mer-ii ENOH +31 -)'-X monomer having group No. 11 No. 11
&■F Oil
'H2υ=U-CIJOe upperzq(J-P-Br, H,
C=to -Cα)+<Jl, -i u-P-II Br 1 (however, n is an integer from 2 to 20) HaαCI C113 1 α on 2 Yariyama α) C-0= to OH2 +4l-P Monomer α O having -X group (51-P-0-Monomer having P- group OH0R otion +61 Monomer JH having -P-0-P- group JH n2e=c-Cuc 田■290-P- (Published by J-P-0■
He0 (branch) - C = 12 (MO7 2 Ayukawa - 〇 = CkL2 Mountain (n is an integer from 2 to 20) +71 -000H group -ils ii, Cc-c (JQti α also ■ HzC =C-UOOCHzChLzooCC[z(Ii
zCCIOR+S+ -C-X-containing heptamer C
Mountain H, C=U-C■CJlzCH BA-Yakutan Kai■F (91-U
-(J-C- group-containing seven-mer-?8' etc.).

The above-mentioned 7-mers having acidic groups are added to neutral (meth)acrylate monomers as FF diluents described below.
．． It is used in a blend of 5% by weight or more.

Neutral monomers include methyl (meth)acrylate, ethyl (meth)acrylate, benzyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-
Hydroxyethyl (meth)acrylate, ethylene glycol di(methacrylate, triethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 2,2-bis[(meth)acryloyloxypolyethoxyphenyl]propane) I
Cki3■ -C-Ca2.1==an integer from 1 to 9, R is H or Un
3), 2,2'-bis(4-(3-methacryloyloxy-2-hydroxypropoxy)phenyl)propane (sometimes referred to as Bis-GMA), and the like.

As the polymerization initiator for polymerizing and curing these seven-mer compositions, in addition to the BPO-amine type, tributylporan and the peroxide-amine-sulfinate system disclosed in Japanese Patent Publication No. 56-33363 are preferably used. . Further, fillers such as quartz powder and glass powder may be added to the adhesive used in the present invention, and therefore, the formed polymer layer may contain an inorganic filler.

Furthermore, the polymer layer in the present invention is obtained by polymerizing and curing an adhesive obtained by dissolving a polymer having one unit of (meth)acrylic yarn having an acidic group in a seven-layer unit that dissolves the polymer. is also formed. The polymer having one (meth)acrylic thread unit having an acidic group has the above-mentioned acidic group (
Although it can be formed by using a meth)acrylic thread yarn as one component, it is preferable to use Ichinomiya functional seven yarn from the viewpoint of solubility. Further, as in the case described above, it is preferable that the amount of seven units having an acidic group is 0.5% by weight or more in the finally formed polymer. It is preferable that the above-mentioned acidic group-containing hexamer is copolymerized with a neutral monofunctional (meth)acrylic monomer such as the one described above, and the thus formed polymer can be copolymerized with various (meth)acrylic monomers.
Since it dissolves in acrylic monomers, it is dissolved at an appropriate concentration and a polymerization initiator is added to form an adhesive. When such an adhesive is polymerized and cured, a polymer layer is formed and it is possible to integrate the calcium phosphate outer layer and the metal substrate. In this case as well, the polymer layer may contain various additives such as inorganic fillers.

Hereinafter, the present invention will be explained in detail with reference to Examples.

(Example) Example 1 Calcium hydroxyapatite sintered body (relative density 97.5%, purity) consisting of an outer diameter of 3.5 Wφ, an inner diameter of 2.0 mm, a bottom thickness of 1.5 mm, and a length of 10 m. 9996), the outer diameter is 1.8 mm (outer diameter of the upper part only is 3.5 mm), the thickness is 0.4 m, the length is 8.9 mm, and the inner surface is 0.313 mm.
GMA 13.6 parts by weight 1,4-butanediol dimethacrylate
12.1 Jushabu 10-methacryloyloxydecyldihy 4.5N drodiene phosphate benzoyl peroxide
0.3 Silanized quartz powder
100 Sodium benzene sulfine brewed
0.3〃N, N-jetanol-P
T-toluidine 0.5 On the other hand, the plug and abutment of the implant were made of the same titanium alloy as that used for the implant, and were threaded at the same pitch as the inner surface of the implant. In FIG. 3, part a of the support is 4-tone, part b is 8.1 mm, part C is 2,8, and part d is 3.5. The buried dental implants were placed in the molars of monkeys and observed for 6 months after the implantation and 3 months after the crown was constructed on the abutment. There wasn't.

Example 2 An artificial tooth root was prepared in the same manner as in Example 1 except that an adhesive having the composition shown below was used.

Adhesive composition: Adhesive 7-terminal coated with the following formula - 2.5 parts by weight UPO
tOii)2 Methyl methacrylate 4
7.5//Polymethyl methacrylate powder
5 Trimethylborane
5. The buried dental implant was placed in the molar region of a monkey and observed for 2 months after placement.
No movement or dislodgement of the implant was observed.

Example 3 An artificial tooth root was prepared in the same manner as in Example 1 except that an adhesive having the composition shown below was used.

Adhesive composition is-GMΔ 17
Part by weight Neopentyl glycol dimethacrylate
13 〃6-methacryloyloxyhexyldihye 2,8 //Drodiene phosphate silane treated quartz powder 1
00 //benzoyl peroxide
0.4 parts by weight Sodium benzenesulfinate 0.3〃N5-jetanol-p-)luidine 0.4〃The buried dental implant was placed in the molar region of a monkey, and the implant was placed on the abutment for 3 months after placement. The implant was observed for one month after construction, but no movement or dislodgement of the implant was observed.

Examples 4 to 6 The same method as in Example 1 except that the monomers shown in Table 1 were used instead of 10-methacryloyloxydecyl dihydride p-diene phosphate as the composition of the adhesive. An artificial tooth root was created.

Table 1 Animal experiments were conducted in the same manner as in Example 1, and the same effects as in Example 1 were obtained.

(Effects of the Invention) According to the present invention, a composite implant in which the calcium phosphate layer and the metal base were firmly integrated was obtained.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an example of a composite implant (for implantable dentistry) according to the present invention, and Fig. 2 shows an example of a plug used to seal the implant shown in Fig. 1. 3 is a sectional view showing an example of an abutment mounted on the implant shown in FIG. 1. FIG.

Claims (6)

[Claims] (1) The surface that comes into contact with the living body is a calcium phosphate layer,
A composite implant in which a metal substrate is provided inside the layer, wherein the calcium phosphate layer and the metal substrate are fixed by a polymer layer whose constituent unit is a (meth)acrylic monomer unit having at least an acidic group. composite implant. (2) The acidic group has a ▲ mathematical formula, chemical formula, table, etc. ▼,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas,
There are tables, etc. ▼, -COOH, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼
(However, X represents halogen.) The composite implant according to claim 1. (3) The acidic group has a ▲ mathematical formula, chemical formula, table, etc. ▼,
The composite implant according to claim 2, which is: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼. (4) The composite implant according to claim 3, wherein the acidic group has a numerical formula, a chemical formula, a table, etc. (5) The (meth)acrylic monomer unit has a general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [However, R_1 is a hydrogen atom or a methyl group,
Ra is a (m+1) valent organic residue having 2 to 40 carbon atoms (the organic residue has a ▲ mathematical formula, chemical formula, table, etc. ▼ group and ▲
Numerical formulas, chemical formulas, tables, etc. are available.
5. The composite implant according to claim 4, wherein the composite implant is a monomer unit represented by the following formula: 1 to 4 alkyl, m is an integer of 1 to 4, and k is 0 or 1. (6) The composite implant according to claim 5, wherein m in the general formula is 1.