Pages 48-53, Language: EnglishYamagami, Akiyoshi / Yoshihara, Yusuke / Suwa, FumihikoTo evaluate the biocompatibility and the bone-bonding strength of new titanium alloy materials treated by sandblasting and anodic oxidization, 3 cylindric test pieces having different surface roughnesses were manufactured and implanted into the diaphyses of the femurs of New Zealand white rabbits. Six weeks later, shear loading tests and histologic examination were carried out. Strong interfacial bonding strength and active new bone formation were confirmed in the peripheral area of the test pieces having a surface roughness (Ra = 2.7 µm and Ra = 4.7 µm). Judging from stable fixation to shear loading in bone tissue, it was concluded that group C (Ra = 2.7 µm) had the best surface condition of the 2 groups. Further detailed examination is required to demonstrate that the surface treatment used for group C (a micro rough surface on a macro rough surface structure) can enhance active bone formation and stable fixation in bone tissue.