Effect of thin nano-hydroxyapatite coating on implant osseointegration in ovariectomized rats

Purpose. The purpose of this study was to investigate the effect of the thin nano-hydroxyapatite (nano-HA) coating on implant osseointegration in an ovariectomized rat model. Materials and Methods. Implants were divided into a control group and a test group (nano-HA-coated group). Surface morphology was examined using field-emission scanning electron microscopy (FSEM). Surface roughness of both groups was performed. Sixteen ovariectomized rats randomly received 2 implants in both tibiae. After 12 weeks of implantation, tibias were retrieved and prepared for histomorphometric evaluation and removal torque tests (RTQ). Results. Rodlike crystals uniformly covered the porous surfaces and the surface morphology of the implant was still clear. No significant differences were found in surface roughness between the 2 groups (P > .05). More bone tissue was formed around test implants compared with control implants. Test implants showed a significantly greater BIC, bone area within all threads, and RTQ values compared with control implants (P < .05). Conclusions. These results indicate the thin nano-HA coating by an electrochemical process has potential benefits to enhance implant osseointegration in ovariectomized rats. (Oral Surg Oral Med Oral Pathol Oral Radiol 2012;113:e48-e53)