Effect of macrogeometry and bone type on insertion torque, primary stability, surface topography damage and titanium...

This study investigated the influence of implant macrogeometry and bone type on insertion torque (IT), primary stability (ISQ), surface topography damage, and the amount of titanium (Ti) released during insertion. Forty implants with different macrogeometries (Facility - Cylindrical with spiral-shaped threads; Alvim - Tapered with buttress-shaped threads) were inserted into artificial bone types I-II and III-IV. Surface morphology was evaluated by Scanning Electron Microscope (SEM) and roughness parameters with Laser Scanning Confocal Microscopy (LSCM) before and after insertion (AI). Implant macrogeometry was characterized by LSCM. The chemical composition of bone beds was determined by SEM associated with Energy Dispersive X-Ray Spectroscopy. The amount of Ti released was analyzed with Energy Dispersive X-Ray Fluorescence. Alvim had greater IT and ISQ than Facility. Bone types I-II require higher IT of implants. Alvim also had greater internal threads angle, higher initial roughness, and significant reduction of roughness AI, compared to Facility. The functional surface height reduced AI, especially in flank and valley of threads. Height of surface roughness of Alvim and Facility implants was similar AI. Implants surface morphology changes and metallic particles on bone beds were observed after implant insertion, mainly into bone types III-IV. Implants inserted into bone types I-II showed less surface damage. Alvim implants released more Ti (37.52 ± 25.03 ppm) than Facility (11.66 ± 28.55 ppm) on bone types III-IV. The implant macrogeometry and bone types affect IT, ISQ, surface damage, and Ti amount released during insertion. Alvim implants were more wear susceptible, releasing higher Ti concentration during insertion into bone types III-IV.