Influence of an 810-nm Diode Laser on the Temperature Changes of the External Root Surface: An In Vitro Study

BACKGROUND AND AIMS: Rising effects of temperature due to laser use during root canal disinfection may harm periodontium and alveolar bone. Therefore, the aim of this study was to estimate the surface root temperature of lower incisors throughout the application of different power levels and times of an 810-nm diode laser. MATERIALS AND METHODS: Sixty single-rooted extracted human lower incisor teeth were selected and chemomechanical preparation was performed. Specimens were irradiated using 810-nm diode laser at 1.05, 1.5, and 1.95 W power settings and two periods of time 20 and 60s, in a continuous wave (CW) mode, without water spray. Specimens were divided into three main groups (n = 20). Each group was subdivided into two subgroups (n = 10). Then, the peak temperatures at the middle and apical regions of the root surface were registered using a thermocouple. RESULTS: Temperature rise of root surface at all the selected output powers was below 7°C. The highest temperature value was obtained in the apical region at 60s when the root canal irradiated at 1.95 W output power. CONCLUSION: Diode laser is safe for use as a root canal disinfectant. Time of exposure to laser irradiation has an effect on the temperature difference at different output powers.