• The effect of neodymium:yttrium-aluminum-garnet laser treatment at different power settings and distances on hydroxyapatite-coated dental implants: A scanning electron microscope study

      Elbanhawy, Omar E.; Reynolds, Mark A., D.D.S., Ph.D. (2013)
      Aim: The purpose of this study was to evaluate the surface changes caused by a single pass of pulsed neodymium:yttrium-aluminum-garnet (Nd:YAG) laser on hydroxyapatite (HA)-coated dental implant surfaces, and to report on the effect of varying the distance from the laser fiber tip to the implant surface on laser induced implant surface changes. Materials and methods: Nine HA-coated tapered screw vent implants (Zimmer Dental, Carlsbad, CA) were used in this study. The laser used was the Periolase<sup>TM</sup> MVP-7<sup>TM</sup>, which is a pulsed Nd:YAG (1062nm) laser. The effect of the laser was evaluated a distance of 3 mm and 10 mm away from implant surfaces at 3 different power settings (0.8 W, 2.0 W, and 3.0 W), which yielded 6 treatment groups: Group 1 (0.8 W at 3mm); Group 2 (0.8 W at 10mm): Group 3 (2.0 W at 3mm); Group 4 (2.0 W at 10mm); Group 5 (3.0 W at 3mm); and Group 6 (3.0 W at 10mm). The implants were examined for the area of surface damage using scanning electron microscopy (SEM). Measurements on SEM images were made at 350x magnification. Data were submitted to an analysis of variance with repeated measures. Results: The mean areas of surface damage were as follows: Group 1 891 μm2 ±129; Group 2 684μm2 ±227; Group 3 2825μm2 ±730; Group 4 2300μm2 ±590; Group 5 5225μm2 ±409; and Group 6 2397μm2 ±370. At 3 mm distance, the mean area of surface damage increased significantly with each higher level of energy. At 10mm distance, the mean area of surface damage increased significantly at 2.0 W and 3.0 W, when compared to 0.8 W; however, no difference was found between 2.0 W and 3.0 W. No obliteration of HA surface was noted. Conclusion: Within the limitations of this study, the surface effects of a single pass of Nd:YAG laser on HA-coated implants appear to be proportional to the laser power output and inversely proportional to the distance from the object being irradiated.
    • The Effects of Neodymium: Yttrium-Aluminum-Garnet Laser (Nd:YAG) On TiUnite® Surface at Set Distance and Energy Level in Different Ambient Environments: An in vitro Scanning Electron Microscopic Evaluation.

      Versteegh, Thu Mai; Aichelmann-Reidy, Mary Beth (2014)
      Background: Lasers are gradually being used more for the surface treatment of contaminated implants in cases of peri-implantitis. Surface effects were recently characterized to evaluate changes to implants in a dry environment, using a single pass of a Nd:YAG laser at a variety of energy densities. The clinical surface treatment of ailing implants is usually complicated by the presence of blood and saliva. The aim of this study was to evaluate via scanning electron microscopy (SEM) the effect of a single pass of a Nd:YAG laser on the TiUnite® implant at 10mm distance and at 3.0 W energy level in different environments (dry, saline, saliva, blood). Methods: A total of eight NobelReplace® TiUnite® Tapered implants were mounted on a jig and pulled at a constant speed across a Nd:YAG laser at an energy level of 3.0W and at a distance of 10mm. Each experimental group (dry, saline, saliva, blood) consisted of two implants. Each of these two implants per group was irradiated on three different surfaces, contributing six samples to each experimental group. Each irradiated surface contributed four threads to the analysis. ImageJ software was used to calculate the area of surface alteration for each thread. Results: It was found that all irradiated implants (wet or dry) had damage on the irradiated surfaces using Nd:YAG laser at the set distance and energy level. The surface alterations on the implants included charring, blackening, loss of surface roughness, flattening, cracking, and in severe cases melting and crater formation. After one-way ANOVA analysis of all experimental groups, there was a statistically significant difference in surface alterations amongst groups (dry or wet). Verified with Tukey HSD test, it was found that there was no statistical difference in surface alterations between the saline and saliva groups. Conclusions: The application of Nd:YAG laser on TiUnite® implants regardless of the ambient environments produced surface damage when observed under SEM with the least damage observed in saline and saliva. Based on this study, it is desirable to irrigate implant surfaces with saline while using Nd:YAG in order to minimize the surface alterations seen in a blood environment.
    • The effects of Neodymium: Yttrium-Aluminum-Garnet laser on the Osseotite® surface: An in vitro scanning electron microscope evaluation

      Rostami, Arash Mike; Reynolds, Mark A., D.D.S., Ph.D. (2013)
      Background: Recently Nd:YAG laser has been proposed as an option to decontaminate the implant surface. The aim of this study was to evaluate the effects of laser irradiation on Osseotite implant surfaces using the Nd:YAG laser. Methods: Four 3i Osseotite® implants were used with each implant providing 3 sides for observation. The implants were mounted in jig that moved the surface perpendicularly past a Nd:YAG laser beam. After positioning at 3mm or 10mm a fresh surface was irradiated with either 0.8w, 2w, or 3w delivered through a 360nm fiber optic tip. The specimens were evaluated using SEM microscopy and the surface area of alteration was recorded using Image J software. Results: The results demonstrated that implant surfaces irradiated with Nd:YAG, regardless of distance (3mm, or 10mm) or power setting (0.8-3W), showed alteration of the Osseotite® surface. Repeated ANOVA analysis showed surface alterations were significant with increased power settings, but not to distance (P=0.005). The altered areas on the implants included charring, bluing, loss of surface roughness and in severe cases, melting, blistering and loss of surface layer as viewed by SEM and clinical photos. Conclusion: Regardless of power setting or distance, use of Nd:YAG on the Osseotite® surfaces will produce surface alterations. The implications of these surface alterations on re-osseointegration are not known.
    • 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

      Ward, Melody Daroogar; Reynolds, Mark A., D.D.S., Ph.D. (2013)
      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.