Thermal Transfer on Splinted Implants During Diode Laser Irradiation In-Vitro.

Objectives: Laser irradiation has been used for treatment of peri-implantitis. Objective: The aim of this study was to evaluate the temperature increase (Delta-T) on implants and implants splinted with a fixed restoration during laser irradiation in vitro.
Methods: Two titanium implants were placed in dense artificial bone and after abutment connection, a metal-ceramic 3-unit-bridge was cemented. A peri-implant defect (3x4x5mm) was created around one of the implants. One coronal (T1) and one apical thermocouple (T3) was placed at the implant with the defect and two additional thermocouples (T2, T4) were placed in respective positions next to the splinted implant. 980nm-diode laser irradiation using continuous and pulsed mode (2W, non-initiated tips, 300µm fiber, non-contact) was performed for 60 seconds. The Delta-T based on baseline was recorded during irradiation. Statistical analysis was performed withrepeated ANOVA.
Results: The recorded Delta-T (^oC; mean±SD) in the thermocouples at 10, 30 and 60 seconds were significantly less than 10 degrees (critical threshold) for T2, T3 and T4 (P<0.001) as follows:
Continuous Mode:
T1: 1.18 ± 0.25; 5.14 ± 0.89; 11 ± 1.44 / T3: 0.06± 0.11; 0.32 ± 0.13; 1.48 ± 0.18 / T2: 0.20 ± 0.09; 0.48 ± 0.19; 1.22 ± 0.30 / T4: 0.02 ± 0.45; 0.10 ± 0.06; 0.26 ± 0.11
Pulsed:
T1:1.62 ± 0.57; 4.90 ± 0.94; 9.66 ± 1.22 / T3: 0.10 ± 0.06; 0.29 ± 0.80; 1.56 ± 0.15 / T2: 0.21 ± 0.10; 0.46 ± 0.21; 1.23 ± 0.27 / T4: 0.04 ± 0.05; 0.15 ± 0.05; 0.32 ± 0.11

Conclusions: Within the limitations of this study, 980nm diode laser irradiation on splinted implants may increase temperature on adjacent splinted implants (due to material conductivity), keeping temperature lower than the critical threshold if power settings and irradiation periods are low to control complications and risks of overheating.