Thermal conduction of titanium implants under CO(2) laser irradiation in vitro

OBJECTIVE: The surgical exposure of dental implants can be performed by means of scalpel, punch, or, with less bleeding, by means of CO(2) laser. Possible overheating of the peri-implant bone tissue should be avoided. The goal of this study was to examine the temperature changes on implants under CO(2) laser irradiation (Luxar CO(2) 20 SP laser from POLYMED, Glattbrugg, Switzerland). STUDY DESIGN: Straumann(®) implants were irradiated with continuous wave (cw), continuous wave with super-pulse (cw/sp), and pulsed wave (pw). The irradiation power was 4, 5, 6, 7, 8, 9, and 10 W and the irradiation times were 10, 20, 30, and 60 s. Similar temperature changes occurred in cw/sp mode and cw mode, but substantially higher temperatures appeared in pulsed wave mode. RESULTS: The quickest temperature changes were observed with cw/sp irradiation (+0.5°C to +41.1°C, depending on the irradiation parameters). Beyond 20 s and 8 W irradiation, a rise exceeding 10°C on the implant surface was found. CONCLUSIONS: Implant diameter and length as well as the setting parameters of the CO(2) laser (irradiation power, irradiation time, and irradiation mode) are important factors to consider so that risk-free implant exposure can be accomplished. Ignoring these factors causes a risk of pathological heating of the irradiated implants and thus the surrounding tissue, which can result in the loss of an implant.