The Effects of Neodymium:Yttrium-Aluminum-Garnet Laser On the TiUnite® Surface at Set Distance and Energy Levels: An in vitro Scanning Electron Microscopic Evaluation

Abstract

Background: Lasers are increasingly being used in the treatment of ailing implants with peri-implantitis. This study sought to evaluate via scanning electron microscopy (SEM) the effect of a single pass of a Nd:YAG laser on the TiUnite® implant surface at pre-determined distance and energy levels. Methods: 6 irradiated NobelReplace® TiUnite® Tapered implants were mounted on a jig and pulled at a constant speed across a Nd:YAG laser at energy levels of 0.8W, 2.0W and 3.0W and at a distance of 3mm or 10mm. Each implant provided 3 treatment surfaces, one per energy setting at the set distance. The first three threads of each implant were selected for analysis under SEM. Imaging software was used to calculate the area of surface alteration for each thread. Results: It was found that the further the laser fiber optic was from the implants the greater the affected area. The area of effect at 3mm at the different energy levels was 21,490μm2 ±7,975, 48,986μm2 ±6,195 and 47,362μm2 ±5,810 for 0.8W, 2.0W and 3.0W, respectively. For the 10mm distance, the area of effect was 11,548μm2 ±3,287, 10,723μm2 ±5,651 and 14,403μm2 ±5,435. The altered areas on the implants included charring, blackening, loss of surface roughness and in severe cases melting, blistering and loss of surface layer. After repeated ANOVA, it was found that distance had a greater effect on implant surface alteration at higher energy levels (2.0W and 3.0W) than at the lower energy level of 0.8W indicating that distance becomes a more significant contributor to implant surface damage when higher energy levels are used. Conclusions: The application of Nd:YAG laser on all implants at all distances produced surface damage when observed under SEM with distance having a greater effect on implant surface changes at higher wattages. It remains to be investigated whether this surface damage is a hindrance to re-osseointegration after treatment of implants with laser.