High strength glass-ceramic containing apatite and alkaline earth metal silicate crystals and process for producing the same

• US 4,560,666 A
• Filed: 12/06/1984
• Issued: 12/24/1985
• Est. Priority Date: 12/20/1983
• Status: Expired due to Fees

• Current Assignee: Hoya Corporation
• Original Assignee: Hoya Corporation
• Inventors: Yoshida, Masahiro, Nakagawa, Kenji
• Primary Examiner(s): McCarthy, Helen M.
• Application Number:
  US06/678,977
• Time in Patent Office: 383 Days
• Field of Search: 501/5, 501/10, 501/73, 501/63, 501/57, 501/58, 501/59, 501/77, 3/1.91, 433/201.1, 433/202, 65/33
• US Class Current: 501/5
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2310/00293 containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61K 6/58 specially adapted for dental implants
• CPC Class Codes: A61K 6/75 Apatite
• CPC Class Codes: A61K 6/807 comprising magnesium oxide
• CPC Class Codes: A61K 6/816 comprising titanium oxide
• CPC Class Codes: A61K 6/818 comprising zirconium oxide
• CPC Class Codes: A61K 6/824 comprising transition metal oxides
• CPC Class Codes: A61K 6/833 Glass-ceramic composites
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: C03C 10/0045 containing SiO2, Al2O3 and MgO as main constituents
• CPC Class Codes: C03C 4/0007 for biologically-compatible glass
• CPC Class Codes: Y10S 623/919 Bone

Abstract

A high strength glass-ceramic containing apatite and alkaline earth metal silicate (diopside/forsterite/akermanite) crystals having an excellent affinity for a living body and a process for producing the same are disclosed. The glass-ceramic is useful as an implant material such as an artificial dental root and an artificial bone.

Claims

1. A high strength glass-ceramic having a bending strength from at least 1500 kg/cm² and containing apatite crystals and at least one alkaline earth metal silicate crystal selected from the group consisting of diopside, forsterite and akermanite and having a composition consisting essentially of, in % by weight,

8 to 34% MgO;

12 to 43% CaO;

25 to 40% SiO₂ ;

10 to 25% P₂ O₅ ;

with proviso of 90% or more MgO+CaO+SiO+P₂ O₅,

0 to 10% Li₂ O;

0 to 5% Na₂ O;

0 to 10% K₂ O;

0 to 10% SrO;

0 to 10% B₂ O₃ ;

0 to 10% TiO₂ ;

0 to 10% Nb₂ O₅ ;

0 to 10% Ta₂ O₅ ; and

0 to 3% F₂,

with proviso of 10% or less Li₂ O+Na₂ O+K₂ O+SrO+B₂ O₃ +TiO₂ +Nb₂ O₅ +Ta₂ O₅ +F₂.

2. A process for producing a high strength glass-ceramic containing apatite crystals and at least one alkaline earth metal silicate crystal, which process comprises

molding glass powders having a particle size of 200 mesh or less and having a composition consisting essentially of, in % by weight,

8 to 34% MgO;

12 to 43% CaO;

25 to 40% SiO₂ ;

10 to 25% P₂ O₅ ;

with proviso of 90% or more MgO+CaO+SiO+P₂ O₅,

0 to 10% Li₂ O;

0 to 5% Na₂ O;

0 to 10% K₂ O;

0 to 10% SrO;

0 to 10% B₂ O₃ ;

0 to 10% TiO₂ ;

0 to 10% Nb₂ O₅ ;

0 to 10% Ta₂ O₅ ; and

0to 3% F₂,

with proviso of 10% or less Li₂ O+Na₂ O+K₂ O+SrO+B₂ O₃ +TiO₂ +Nb₂ O₅ +Ta₂ O₅ +F₂,

heat treating the resulting molding in a sintering temperature range of the glass powders, and

heat treating the molding in the temperature range where alkaline earth metal silicate crystals selected from the group consisting of diopside, forsterite and akermanite are formed.

3. A high strength glass-ceramic having a bending strength from at least 1500 kg/cm² and containing apatite crystals and at least one alkaline earth metal silicate crystal selected from the group consisting of diopside, forsterite and akermanite and having a composition consisting essentially of, in % by weight,

8 to 34% MgO;

12 to 43% CaO;

25 to 40% SiO₂ ;

10 to 25% P₂ O₅ ;

1 to 10% Al₂ O₃, ZrO₂ or both

with proviso of 90% or more MgO+CaO+SiO+P₂ O₅ +(Al₂ O₃ +ZrO₂),

0 to 10% Li₂ O;

0 to 5% Na₂ O;

0 to 10% K₂ O;

0 to 10% SrO;

0 to 10% B₂ O₃ ;

0 to 10% TiO₂ ;

0 to 10% Nb₂ O₅ ;

0 to 10% Ta₂ O₅ ; and

0 to 3% F₂,

with proviso of 10% or less Li₂ O+Na₂ O+K₂ O+SrO+B₂ O₃ +TiO₂ +Nb₂ O₅ +Ta₂ O₅ +F₂.

4. A process for producing a high strength glass-ceramic containing apatite crystals and at least one alkaline earth metal silicate crystal, which process comprises

(1) molding glass powders having a particle size of 200 mesh or less and having a composition consisting essentially of, in % by weight,

8 to 34% MgO;

12 to 43% CaO;

25 to 40% SiO₂ ;

10 to 25% P₂ O₅ ;

1 to 10% Al₂ O₃, ZrO₂ or both

with proviso of 90% or more MgO+CaO+SiO+P₂ O₅ +(Al₂ O₃ +ZrO₂),

0 to 10% Li₂ O;

0 to 5% Na₂ O;

0 to 10% K₂ O;

0 to 10% SrO;

0 to 10% B₂ O₃ ;

0 to 10% TiO₂ ;

0 to 10% Nb₂ O₅ ;

0 to 10% Ta₂ O₅ ; and

0 to 3% F₂,

with proviso of 10% or less Li₂ O+Na₂ O+K₂ O+SrO+B₂ O₃ +TiO₂ +Nb₂ O₅ +Ta₂ O₅ +F₂,

(2) heat treating the resulting molding in a sintering temperature range of the glass powders, and

(3) heat treating the molding in the temperature range where alkaline earth metal silicate crystals selected from the group consisting of diopside, forsterite and akermanite are formed.