title: Cell-mediated bioresorption of sintered carbonate apatite in rabbits.
abstract: Bone apatite contains carbonate and is therefore not pure hydroxyapatite. We have successfully developed sintered carbonate apatite (CA) with a concentration of carbonate of 6 weight% and have evaluated its osteoconductive and bioresorption characteristics. Cylindrical porous sintered CA and sintered hydroxyapatite (HA) measuring 4 x 4 mm with a porosity of 20% were implanted into surgically-created bone defects in the knees of rabbits. The animals were killed after 1, 3, 6 and 12 months. The defects were evaluated by microfocus CT and histology. Bone growth into and around both materials increased. Newly-formed bone was placed in direct contact with both. Osteoclast-like cells resorbed only CA, and were coupled with osteoblasts. The porosity of sintered CA increased, indicating bioresorption, whereas that of sintered HA did not increase. Our findings indicate that sintered CA may be useful as a bioresorbable bone substitute.
authors.affiliation: Department of Orthopaedic Surgery, Mie University Faculty of Medicine, Tsu City, Mie, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hasegawa
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Doi
authors.forename: Atsumasa
authors.initials: A
authors.lastname: Uchida
mesh_terms: D000818:Animals; D001031:Apatites / Q000378:metabolism*; D001842:Bone and Bones / Q000000981:diagnostic imaging* / Q000502:physiology; D005260:Female; D006882:Hydroxyapatites / Q000378:metabolism*; D008854:Microscopy, Electron; D016348:Osseointegration / Q000502:physiology*; D019736:Prostheses and Implants; D011817:Rabbits; D014463:Ultrasonography
chemical_list: D001031:Apatites; D006882:Hydroxyapatites; C030782:carboapatite