title: The evaluation of a biphasic calcium phosphate ceramic for use in grafting long-bone diaphyseal defects.
abstract: The effectiveness of a sintered hydroxyapatite-tricalcium phosphate (HA-TCP) ceramic in bridging large diaphyseal defects in the canine ulna was studied. One-hundred percent morselized HA-TCP, a 50:50 mixture of morselized HA-TCP, and autogenous cancellous bone, and 100% autogenous cancellous bone were used to bridge 2.5-cm defects in the left ulnae of three groups of six dogs each. At 24 weeks the ulnae were explanted and studied by radiography, microradiography, mechanical testing, and histology. Pure HA/TCP was not osteoinductive, and four of six ulnae in this group progressed to a fibrous nonunion. The HA/TCP-cancellous bone mixture and pure cancellous bone were approximately equal in effect, leading to good callus formation at 4 weeks and strong bony union by 24 weeks, with no evidence of bioincompatibility. Morselized HA/TCP promises to be useful as a graft extender when mixed with autogenous cancellous bone.
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D016025:Bone Transplantation; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000601:surgery; D002130:Calcium Phosphates; D002516:Ceramics; D004285:Dogs; D017886:Durapatite; D005069:Evaluation Studies as Topic; D005599:Fractures, Ununited / Q000601:surgery; D006882:Hydroxyapatites; D008852:Microradiography; D014458:Ulna Fractures / Q000601:surgery; D014945:Wound Healing
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; D006882:Hydroxyapatites; C485817:beta-tricalcium phosphate; D017886:Durapatite; C018392:tricalcium phosphate