Evaluation of the effect of phosphate-coated and acid-etched titanium on osseointegration in the canine model

The effects of phosphate titanium were evaluated on mineral apposition rate and new bone-to-implant contact in canines. 2.2 mm x 4 mm acid-etched or phosphated titanium implants were placed in 48 mandibular sites in 6 foxhounds. Tetracycline and calcein dyes were administered 1 week after implant placement and 1 week before sacrifice. Mineral apposition rate (MAR) and bone-to-implant contact (BIC) were evaluated using fluorescence microscopy. Light microscopic and histological evaluation was performed on undecalcified sections. Healthy osteoblasts lined bone surfaces near implants. Similar BIC was observed in acid-etched and phosphated implants. MAR was significantly higher near non-phosphated implant surfaces than the phosphated titanium samples. No significant differences were found between dogs or implant sites. Bone-to-implant contact was unaffected by surface treatment. Phosphated implants decreased the mineral apposition rate of bone near the implant surfaces.