title: Hydroxyapatite-clay bone fixation for loaded implants.
abstract: A clay containing hydroxyapatite (HA clay), which was made by mixing HA granules (range of sizes: 0.1-0.3 mm) and a saline solution of sodium alginate, was inserted into the medullary canal of an osteotomized rabbit's tibia with a Ti-6Al-4V titanium alloy implant. Each implant had a conical portion for bearing load. The shear strength of the bone-implant interface for the implant with HA clay was significantly greater than that for the implant without HA clay 3 months postoperatively (P < .02), while there was no significant difference between the two strengths 1 week postoperatively. Under microscopic observation, the percentage of area of newly developed bone was also significantly greater for the implant with HA clay than for the implant without HA clay 3 months postoperatively (P < .04). This study suggests that HA clay encouraged adequate bone fixation of the loaded implant in 3 months, while the clay was not effective for immediate fixation.
authors.affiliation: Department of Orthopaedic Surgery, Shinshu University School of Medicine, Matsumoto, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Maruyama
mesh_terms: D000497:Alloys; D000818:Animals; D001846:Bone Development; D001842:Bone and Bones / Q000033:anatomy & histology*; D006882:Hydroxyapatites; D009984:Orthopedic Fixation Devices; D019736:Prostheses and Implants; D011817:Rabbits; D013977:Tibia / Q000033:anatomy & histology / Q000502:physiology; D014025:Titanium
chemical_list: D000497:Alloys; D006882:Hydroxyapatites; C031462:titanium alloy (TiAl6V4); D014025:Titanium