Evaluation of Temperature and Roughness Alteration of Diode Laser Irradiation of Zirconia and Titanium for Peri-Implantitis Treatment.

Abstract

This study investigated the effects of diode laser (gallium, aluminium, arsenide [GaAlAs]) irradiation with decontamination parameters on the temperature and roughness of yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP), titanium (TI), and sandblasted large grit acid-etched titanium (SLA). Three groups (n = 10) of standardized disks with 5 mm diameter and 2 mm thickness were produced with Y-TZP obtained from computer-aided design and computer-aided manufacturing (CAD-CAM), machined TI and SLA. The diode laser single application (808 nm, 20 sec, 1 W, 50 Hz, t on = 100 ms, t off = 100 ms, energy density = 28.29 J/cm(2)) was performed in contact mode, on each disk. The temperature was measured by a thermosensor attached to a digital thermometer fixed to the opposite irradiated surface. The temperature gradient (ΔT) was calculated (ΔT = final temperature - initial temperature) for each group. The parameters Ra (in μm) and Sa (in μm(2)) were measured by white light confocal laser microscopy to express the surface roughness. Data of ΔT was statistically analyzed by one way ANOVA at the 95% confidence level and compared by Tukey post-hoc test (α = 0.05). Roughness data was analyzed by t test. The diode laser irradiation presented the following results (ΔT value): Y-TZP = 10.3°C(B); TI = 38.6°C(A), and SLA = 26.7°C(A). The ΔT values ((°)C) of the titanium groups were higher than for the Y-TZP group. For both roughness parameters (Ra and Sa), data did not show statistical significant differences to "irradiation" factor (p > 0.05) to Y-TZP and SLA. The Ra results (in μm) were: Y-TZP (control) = 0.73 (0.55); Y-TZP (irradiated) = 0.45 (0.27); SLA (control) = 0.74 (0.23); and SLA (irradiated) = 0.99 (0.33). The Sa results (in μm(2)) were: Y-TZP (control) = 1.39 (1.05); Y-TZP (irradiated) = 0.73 (0.41); SLA (control) = 0.85 (0.08); and SLA (irradiated) = 1.27 (0.44). Diode laser irradiation for peri-implantitis treatment increased both zirconia and TI temperature without surface roughness alterations.