Effect of alendronate on healing of extraction sockets and healing around implants.

OBJECTIVES

The purpose of this study was to evaluate the effect of alendronates on healing of extraction sockets and healing around implants in the maxilla of rats.

MATERIALS AND METHODS

Twenty-four Sprague-Dawley rats were used. The rats in bisphosphonate group were subcutaneously injected with alendronate (5.0 mg kg(--1)) three times a week for 4 weeks. Both sides of the maxillary first molars were extracted, and customized titanium implants (Ø1.5 × 2.0 mm) were placed immediately into one side. Rats were killed at 3, 7, 14, or 28 days following surgery.

RESULTS

New bone formation in extraction sockets, bone area around the implant site, and bone-implant contact were not delayed in the bisphosphonate group. The tartrate-resistant acid phosphatase positive cell count did not differ between bisphosphonate and control groups; however, empty lacunae were observed significantly more in bisphosphonate group. The differences in empty lacunae were shown at different time points between the implant sites and extraction sites: at 7 days after extraction, and at 14 and 28 days after implantation.

CONCLUSIONS

Alendronates seemed to decrease bone resorption but not to decrease bone formation. Empty lacunae were observed significantly more at later time points in implant sites compared to extraction sockets.