Short-term immunosuppressive therapy does not affect the density of the pre-existing bone around titanium implants placed in rabbits.

The aim of this study was to evaluate the influence of the administration and withdrawal of cyclosporin A/nifedipine on the bone density in a lateral area adjacent to implants placed in rabbits. Two screw-type titanium implants were placed bilaterally in twenty-eight New Zealand rabbits. The animals were assigned to one of the following groups and received daily subcutaneous injections for 14 days: Groups A and C: vehicle (dimethyl sulfoxide); Groups B and D: CsA (10 mg/kg) plus nifedipine (50 mg/kg). The animals in Groups A and B were sacrificed 14 days postoperatively and, in Groups C and D, 42 days postoperatively. After sacrifice, the tibiae were removed and undecalcified sections were obtained. Bone density was obtained in a 500 mm-wide zone lateral to the implant surface. Intergroup analysis showed no significant difference (p > 0.05) in the degree of bone density between control and test groups either on day 14 or on day 42. Thus, it appears that a short-term immunosuppressive therapy may not present a negative influence on the density of the pre-existing bone around titanium implants placed in rabbits.