Experimental study of bone response to hydroxyapatite coating implants: bone-implant contact and removal torque test

Objective. The objective of this study was to evaluate the early osseointegration of hydroxyapatite (HA)-coated implant. Study Design. Twelve adult male miniature pigs were used in this study. The removal torque of implants placed in the tibia of miniature pigs was measured. For implants placed in the mandible, histomorphometric evaluation was performed for the evaluation of the bone-implant contact (BIC) ratio. Results. After 4, 8, and 12 weeks, removal torque values were increased. Among the 3 groups, the HA-coated group showed the highest values (P < .05). At 4 and 8 weeks, the BIC ratio of HA was significantly higher than that of resorbable blast medium or sand blasted with alumina and acid etched (P < .05). Conclusions. It was concluded that HA-coated implants are relatively favorable in early loading stages. (Oral Surg Oral Med Oral Pathol Oral Radiol 2012;114:411-418)