Improved Retention and Bone-to-Implant Contact with Fluoride-Modified Titanium Implants

Purpose: The purpose of the present study was to investigate whether a fluoride modification of the titanium surface would have an effect on bone response after implantation. Materials and Methods: Titanium-oxide-blasted titanium implants with and without fluoride modification were investigated in a rabbit tibia model. Quantitative analysis of surface roughness, biomechanical interlocking, and in vivo tissue reactions in rabbit bone at 1 and 3 months after placement were compared. Results: The fluoride-modified test implants had a slightly smoother surface (Sa: 0.91 ± 0.14 µm) than the unmodified control implants (S_a: 1.12 ± 0.24 µm). Significantly higher removal torque values (85 ± 16 Ncm vs 54 ± 12 Ncm) and shear strength between bone and implants (23 ± 9 N/mm² vs 15 ± 5 N/mm²) were measured for the fluoride-modified implants after 3 months. The histomorphometric evaluations demonstrated higher bone-to-implant contact for test implants at 1 month (35% ± 14% vs 26% ± 8%) and 3 months (39% ± 11% vs 31% ± 6%) after placement. Discussion: Implant surface modification with fluoride may result in morphologic and physiochemical phenomena that are of significance for the bone response. Another possible explanation for the findings in the present study is that a surface modification changes the surface chemical structures to be more suitable for bone bonding. Conclusion: Based on the biomechanical and histomorphometric data, the fluoride-modified titanium implants demonstrated a firmer bone anchorage than the unmodified titanium implants. These implants achieved greater bone integration than unmodified titanium implants after a shorter healing time. (More than 50 references.)