Biocompatible ceramic glass

• US 4,120,730 A
• Filed: 02/18/1976
• Issued: 10/17/1978
• Est. Priority Date: 02/20/1975
• Status: Expired due to Term

• Current Assignee: Battelle Memorial Institute
• Original Assignee: Battelle Memorial Institute
• Inventors: Tannenberger, Helmut, Trojer, Felix, O'Connor, Grahame Paul
• Primary Examiner(s): Vertiz, O. R.
• Assistant Examiner(s): Bell, Mark
• Application Number:
  US05/659,019
• Time in Patent Office: 972 Days
• Field of Search: 106/52, 106/39.6, 3/1.9
• US Class Current: 501/3
• CPC Class Codes: A61F 2310/00293 containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61L 27/10 Ceramics or glasses
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: C03C 10/0009 containing silica as main constituent
• CPC Class Codes: C03C 4/0007 for biologically-compatible glass
• CPC Class Codes: Y10S 623/923 Bone

Abstract

A biocompatible glass ceramic consisting of a vitreous matrix containing vitreous inclusions in which are dispersed crystals of a compound, isomorphous with hydroxyapatite, of at least the following elements: calcium, a lanthanide or yttrium, silicon, phosphorus and oxygen, these inclusions being surrounded by crystals of at least one compound belonging to the group consisting of Na₂ Ca₂ Si₃ O₉ and Ca₃ (PO₄)₂.2 Ca₂ SiO₄, can be used to construct artificial bone segments etc in bone surgery and bonds firmly with the new bone tissue without causing inflammation.

Claims

1. A biocompatible glass ceramic consisting essentially of a Na₂ O, CaO and SiO₂ vitreous matrix containing vitreous inclusions in which are dispersed crystals of a compound isomorphous with hydroxyapatite and having the formula Ca.sub.(10-x) M_x Si_x P.sub.(6-x) O₂₄ F₂, where x is 2 to 6 and M is a lanthanide or yttrium, and crystals of Na₂ Ca₂ Si₃ O₉ and Ca₃ (PO₄)₂.2Ca₂ SiO₄ in said matrix, said crystals being present in an effective amount to permit bonding of said glass ceramic to bone, the glass ceramic being prepared from a mixture having the following molar percentage limits:

SiO₂ = 35 to 50

Na₂ O = 20 to 30

CaO = 10 to 30

P₂ o₅ = 2.5 to 10

lanthanide or yttrium oxide = 3 to 10

alumina = up to 5

sodium fluoride = up to 10

calcium fluoride = up to 5.

2. The glass ceramic defined in claim 1 wherein said lanthanide is lanthanum.

3. The glass ceramic defined in claim 2 wherein said compound isomorphous with hydroxyapatite is a compound of the formula

4. The glass ceramic defined in claim 1 wherein said compound isomorphous with hydroxyapatite is a compound of the formula

5. The glass ceramic defined in claim 1 wherein said crystals isomorphous with hydroxyapatite include said lanthanide or yttrium in a nontoxic quantity but sufficient to permit partial dissolution of the glass ceramic to form holes and allow growth of bone tissue in these holes whereby the lanthanide or yttrium is incorporated in the bone tissue thus grown in the holes whereby epitaxy exists between the hydroxyapatite phase of the bone and crystals of the ceramic glass isomorphous with the hydroxyapatite.