New laser-treated implant surfaces: a histologic and histomorphometric pilot study in rabbits.

PURPOSE The purpose of this study was to confirm the validity of laser treated implant surfaces, with regard to high superficial purity preservation and to extremely regular and uniform roughness surfaces. METHODS In this in vivo study, seven different laser treated implant surfaces were analyzed. A diode-pumped solid state source laser, in a Q-Switch output mode, was used at various wavelengths, which were chosen to generate surface irregularities of varying diameter, depth and pitch. Twenty one implants were placed in 11 New Zealand rabbits. Eight weeks after surgery, implants were harvested for histometric analysis: total, threads and body bone-to-implant, and bone-to-implant contacts were measured. The morphologic analysis of the surface was carried out using a Scanning Electron Microscope. RESULTS Average bone-implant contact values were approximately 50% for all tested surfaces. Both total and threads values, within the same processing pattern group, had a high variance. Bone-implant contact thread and body variances were different, so that is possible that laser beam angle is able to modify the superficial roughness and thus the histological response. CONCLUSIONS Implants provided with pores of 20 and 25 µm achieved more than satisfactory bone-implant contact partial peaks. Further statistically significant experiments are needed in order to study, in depth, these surfaces.