Characterization and in vivo evaluation of laser sintered dental endosseous implants in dogs

Laser metal sintering has shown promising results, but no comparison with other commercially available surface has been performed. This study sought to evaluate the biomechanical and histological early bone response to laser sintered implants relative to alumina-blasted/acid-etched (AB/AE). Surface topography was characterized by scanning electron microscopy and optical interferometry. Surface chemistry was assessed by x-ray photoelectron spectroscopy. Beagle dogs (n = 18) received 4 Ti-6Al-4V implants (one per surface) in each radius, remaining for 1, 3, and 6 weeks (n = 6 dogs per evaluation time) in vivo. Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) were evaluated. Biomechanical evaluation comprised torque-to-interface failure. The laser sintered surface presented higher S(a) and S(q) than AB/AE. Chemistry assessment showed the alloy metallic components along with adsorbed carbon species. Significantly higher torque was observed at 1 (p < 0.02) and 6 week (p < 0.02) for the laser sintered, whereas at 3 week no significant differences were observed. Significantly higher BIC and BAFO was observed for the Laser Sintered (p < 0.04, and p < 0.03, respectively) only at 1 week, whereas no significant differences were observed at 3 and 6 weeks. The laser sintered implants presented biocompatible and osseoconductive properties and improved biomechanical response compared with the AB/AE surface only at 1 and 6 weeks in vivo.