JP3064077B2 - Composite implant components - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to diseases, disasters, etc.
Orthopedic artificial bones and joints used to repair bone and limb joint functions when they are lost,
Alternatively, the present invention relates to a composite implant member embedded in a living body constituting an artificial tooth root or the like used for reconstructing a tooth lost due to aging, disease, or the like.

[0002]

2. Description of the Related Art As a composite implant member combining a titanium material and zirconia ceramics which has already been clinically used, for example, there is an artificial hip joint in which a zirconia ball and a titanium stem are fitted with a taper as an implant to be implanted in bone. . This is obtained by integrating a zirconia ball having excellent sliding characteristics and strength in a living body with a titanium stem having excellent toughness, strength and corrosion resistance. In addition, in the orthopedic field, in addition to the above-mentioned artificial hip joints, artificial titanium joints, ankle joints, shoulder joints, hand joints and the like are joined with zirconia ceramics containing zirconia as a main component and a titanium material made of titanium or a titanium alloy. There are implant applications.

[0003] Further, in the dental field, application to an implant implantable in bone has been considered. Currently, implants are used in which porous alumina is bonded to bone with porous alumina bonded to sapphire core material with glass, but there was a problem in strength because the core was sapphire . In order to improve this point, development of an implant in which porous zirconia ceramics are bonded to a titanium core material to form a composite is expected.

Conventionally, a titanium material and a zirconia ceramic have been combined in an implant by coating the surface of the titanium material with zirconia by a spraying method, a CVD method, a PVD method, an anodic oxidation method, or the like, When both were in bulk, they were joined by the active metal method. This is a method in which a paste of a Ti-Al-Cu alloy or the like is applied to the interface between the titanium material and the zirconia ceramics, and the two are abutted and heated for joining, whereby a relatively strong joint has been obtained.

[0005]

2. Description of the Related Art However, CVD, PVD
The zirconia coating layer produced by the method or the anodic oxidation method had a thickness of only several thousand angstroms to about 10 μm, and the coating layer had no durability. On the other hand, according to the thermal spraying method, the thickness can be reduced to several tens to several hundreds of μm.However, in this method, the strength depends on only the anchor effect due to minute irregularities on the surface of the titanium material as the base material, so that the strength is low. There's a problem.

In the case of a composite implant member manufactured by the active metal method, intense galvanic corrosion occurs between titanium at the interface and the metal contained in the brazing material used for bonding, and in particular, moisture such as in a living body. There was a problem that it was not suitable for an environment with many.

[0007]

To solve the above problems SUMMARY OF THE INVENTION The present invention provides a zirconia ceramic mainly comprising titanium material and zirconia consisting of pure titanium or a titanium alloy, a SiO ₂ 60~80wt%, BaO 5 to 15
wt%, a K ₂ O 5 ~12wt%, a Na ₂ O. 5 to 12
The present invention provides a composite implant member which is bonded and integrated with glass containing 0 to 7 wt% of ZnO and 0 to 7 wt%.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. Since both the titanium material and the zirconia ceramic have approximately the same coefficient of thermal expansion at around 10 × 10 ⁻⁶ / deg, they are heated during autoclave sterilization and gas sterilization if they are joined via living glass having a similar coefficient of thermal expansion. This may cause damage to the joint surface between the titanium material and the zirconia ceramic of the composite implant member that combines the titanium material made of pure titanium or titanium alloy and the zirconia ceramic mainly composed of zirconia, and cracks in the zirconia ceramic. It has been found that a biomaterial that does not cause the generation of a biomaterial can be constructed.

Therefore, first, as shown in FIG.
25m in diameter made of a titanium alloy containing 4% by weight of t% and V
m, 40 pieces of titanium material 2 having a height of 60 mm and 40 pieces of zirconia ceramics 3 having a diameter of 25 mm and a height of 60 mm, containing zirconia as a main component and containing 4.5 wt% of Y ₂ O _3. did. Subsequently, 7 of SiO ₂
0 wt%, BaO 10 wt%, K ₂ O 8 wt% , N
A glass powder containing 7 wt% of a ₂ O and 5 wt% of ZnO and having an average particle diameter of 100 μm was prepared, and ethanol was added thereto to form a paste. Then, the paste-like glass powder is applied to one of the 20 end faces 2a, 3a having a diameter of 25 mm of the titanium material 2 and the zirconia ceramics 3 each of 20 pieces, and the two are abutted one by one. It was fixed so that it did not slip with a jig. Further, these are subjected to a maximum temperature of 800 ° C. and a degree of vacuum of 10 ⁻³ torr.
After softening the glass 4 by heat treatment under the conditions described above, the glass 4 is naturally cooled and a titanium material 2 made of titanium or a titanium alloy and a zirconia ceramics 3 containing zirconia as a main component as shown in FIG. Twenty composite implant members 1 of the present invention joined by glass 4 were produced.

For comparison, the titanium material 2 and the zirconia ceramics 3 were each coated with an active metal braze on the remaining 20 pieces and joined together by a test piece by the active metal method. A comparative specimen was prepared.

Next, fifteen of the twenty composite implant members 1 and fifteen of the twenty comparative test specimens were immersed in Ringer's solution at 37 ° C., and were immersed every 3, 6, 12 months. Ten pieces were taken out of each piece, a tensile test was performed in the major axis direction, and the breaking strength at the interface of the cylindrical pieces was measured. The remaining five pieces were measured for breaking strength by the above method without immersion. Table 1 shows the results.

[0012]

[Table 1]

As is clear from Table 1, the bonding strength of the composite implant member 1 of the present invention hardly changes even after 12 months. On the other hand, in the comparative specimen prepared using the active metal method, the bonding strength was about 1/4 in 3 months.
After 6 months, the bonding was canceled and the bonding strength became zero. In the third month, severe corrosion was already observed in the brazing material, and the immersion liquid was extremely turbid.

Next, a cylindrical body having a diameter of 25 mm and a height of 60 mm, containing zirconia as a main component and adding Y ₂ O ₃ of 2.5 wt.
% Zirconia ceramic 3 including a cylindrical body having the same dimensions Y ₂ O ₃ and 6.5 wt% and Al ₂ O ₃ of 20 wt%
It is made of a titanium alloy containing 6 wt% of Al and 4 wt% of V, each having a zirconia 3 content of 25 mm in diameter,
Two titanium materials 2 each of which is a cylindrical body having a height of 60 mm are produced,
Subsequently, as shown in FIG. 2, two kinds of composite implant members 1 were prepared by joining a titanium material and zirconia ceramics 3 with a glass 4 having a thickness of 50 μm and a thickness of 50 μm. An experiment similar to the above immersion experiment was performed, but almost the same result as that of the composite implant member 1 was obtained. This is because the thermal expansion coefficient of the titanium material 2 and the zirconia ceramic 3 does not change even if the composition changes.

Next, in order to limit the effective composition of glass which is a component of the present invention, an experiment as described below was conducted. As shown in FIG. 1, 6 wt% of Al and 4 wt% of V
14 titanium materials 2 each having a diameter of 25 mm and a height of 60 mm made of a titanium alloy containing titanium alloy, and a cylindrical body having a diameter of 25 mm and a height of 60 mm, containing zirconia as a main component and Y ₂ O
₃ Zirconia Ceramics 3 containing 4.5 wt% of the 14
This was produced. Subsequently, glass powders having the compositions of A to G in Table 2 and having an average particle diameter of 100 μm were prepared, and ethanol was added to each to form a paste. Then, each paste-like glass powder is applied to one of the circular end faces 2a, 3a having a diameter of 25 mm of the titanium material 2 and the zirconia ceramics 3, and the two are abutted one by one. It was fixed with a jig so that it would not slip.
Further, these are heated to a maximum temperature of 800 ° C. and a degree of vacuum of 10 ⁻³ torr.
After softening the glass by heat treatment under the condition of r, the glass is naturally cooled, and a titanium material 2 made of titanium or a titanium alloy and a zirconia ceramics 3 containing zirconia as a main component as shown in FIG. A total of 14 composite implant members 1 of the present invention joined by the glass 4 were produced, two for each of the glass components A to G.

[0016]

[Table 2]

[0017] Tensile tests were performed in the long axis direction for each of the composite implant members 1 using glass having different compositions of A to G, and the fracture strength at the interface of the cylindrical pieces was measured. The value was taken as the bonding strength. The remaining seven were immersed in a physiological saline solution at 70 ° C. for 90 days, and the bonding strength was determined in the same manner. Table 2 shows the results.

As is clear from Table 2, glasses B, C,
For those using D, E, and F, the bonding strength was 2800 kgf or more even after 90 days, and almost no decrease in strength due to immersion was observed.

The bonding strength of 2800 kgf is approximately 570 kgf / cm ² when converted into the strength per unit area, and the tensile strength of the interface bone of an adult human is reported to be 107 kgf / cm ^2. Introduction to Orthopedic Biomechanics ”, p. 27), about 5.2 of that value.
This is double the tensile strength of the implant.

Therefore, the preferred glass is SiO ₂
0~80wt%, 5~15wt% of BaO, and K ₂ O 5
~12wt%, in which a. 5 to 12 wt% and ZnO of Na ₂ O containing 0~7wt%.

Next, as shown in FIG. 3, a titanium material 2 made of pure titanium and having a diameter of 2.5 mm and a height of 7 mm, and a through hole 2 having an outer diameter of 4.0 mm and provided in the axial direction.
A cylindrical body made of porous zirconia having a pore diameter of 2.7 mm and a height of 7 mm (porosity 30%, porosity 100 to 20)
Zirconia ceramics 3 having a thickness of 0 μm).
Subsequently, 70 wt% of SiO ₂ , 10 wt% of BaO,
8 wt% of K ₂ O, 7 wt% of Na ₂ O, and 5 of ZnO
A glass powder containing 30% by weight and having an average particle diameter of 30% by weight was prepared, and ethanol was added thereto to form a paste. Then, a paste-like glass powder is applied to the curved side surface 2 b of the titanium material 2, and this is applied to the alumina ceramic 3.
And then heat-treated in an Ar gas atmosphere at a maximum temperature of 1200 ° C. to soften the glass 4 and then naturally cooled to form titanium or titanium as shown in FIG. A titanium material 2 made of a titanium alloy and a zirconia ceramic 3 containing zirconia as a main component are 2 m thick.
Three composite implant members 1 of the present invention, which were joined with the glass 4 of m, were manufactured.

In parallel, the diameter is 4.0 mm and the height is 7 m.
m of porous zirconia having a porosity of 30% and a pore diameter of 100 to 200 μm.
This was produced.

After the composite implant member 1 and the comparative specimen prepared as described above were subjected to autoclave sterilization treatment, they were respectively implanted into the bone marrow of the tibia of a rabbit, and sacrificed at 3, 6, and 12 months. The extracted composite implant member 1, the comparative specimen and the surrounding tissue were searched. As a result, 3
No significant difference was observed between the composite implant member 1 and the comparative specimen at any of the six months, the sixth month and the twelfth month. By the sixth month, both had already had porous zirconia ceramics with a porous bone structure. 700 μm from the side of 3
Penetrated to the depth of the bone and was firmly fixed in the bone. In addition, there was no damage or destruction of the glass of the composite implant member 1 or cracks generated in the porous zirconia ceramics 3.

This indicates that the glass 4 used for bonding has no adverse effect on the surrounding tissue in the living body and is in a stable state in the living body.

The thickness of the glass 4 is 3 μm to 3 μm.
mm is preferable, and if it is thinner than 3 μm, it is impossible to apply the glass 4 without unevenness, and if it exceeds 3 mm, the strength becomes insufficient. From the viewpoint of strength, the most preferable thickness of the glass 4 is about 50 to 600 μm.

5 to 9 show application examples of the composite implant member of the present invention. Reference numeral 2 denotes a titanium material made of titanium or a titanium alloy, 3 denotes a zirconia ceramic containing zirconia as a main component, and 4 denotes glass.

In FIG. 5, reference numeral 10 denotes a composite implant member which is a screw-type artificial tooth root.
Reference numeral 1 denotes a zirconia ceramic 3 made of porous zirconia having a screw-shaped outer surface formed by bonding a glass 4 around a titanium material 2 which is a base material of a titanium alloy. Such a screw portion 11 has excellent strength,
It also showed excellent osteoinductive ability.

6 and 7, reference numeral 20 denotes a composite implant member which is a femoral member of an artificial knee joint.
A zirconia ceramic 3 made of dense zirconia ceramic is bonded to a lower sliding surface portion 21, 21 of a titanium material 2 made of a titanium alloy constituting a main body with a glass 4. Such a sliding surface portion 21 exhibited good strength and sliding characteristics.

8 and 9, reference numeral 30 denotes a composite implant member which is a stem member of an artificial hip joint.
The zirconia bead part 31 is a main body, and a titanium member 2 made of a titanium alloy and a zirconia member 3 which is a combined body of separately produced zirconia beads are bonded with glass 3. Such zirconia bead portions 31 exhibited excellent strength and good osteoinductive ability.

[0030]

According to the composite implant member of the present invention, a decrease in bonding strength is small even after long-term use in a living body.
Also, there is no adverse effect on the living body.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a titanium material and zirconia ceramics.

FIG. 2 is a perspective view showing a composite implant of the present invention.

FIG. 3 is a perspective view showing a titanium material and zirconia ceramics.

FIG. 4 is a perspective view showing a composite implant of the present invention.

FIG. 5 is a partial cross-sectional side view showing the application of the composite implant member of the present invention to an artificial dental root.

FIG. 6 is a front view showing the application of the composite implant member of the present invention to a tibial member of an artificial knee joint.

FIG. 7 is a sectional view taken along line AA of FIG. 6;

FIG. 8 is a side view showing the application of the composite implant member of the present invention to an artificial hip joint stem member.

FIG. 9 is a sectional view taken along line BB of FIG. 8;

[Explanation of symbols]

 2 titanium material 3 zirconia ceramics 4 glass 1,10,20,30 composite implant member

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI A61F 2/30 A61F 2/30 C03C 8/04 C03C 8/04 C04B 37/02 C04B 37/02 A

Claims (1)

(57) [Claims] The zirconia ceramic mainly composed of 1. A titanium material and zirconia consisting of pure titanium or a titanium alloy, a SiO ₂ 60~80wt%, the BaO 5 to 15
wt%, a K ₂ O 5 ~12wt%, a Na ₂ O. 5 to 12
A composite implant member joined and integrated with glass containing 0% to 7% by weight of ZnO.