Thermal effects on pulp due to laser and handpiece usage.

Objective: The study was designed to compare changes in pulpal temperature during ablation of dental hard tissue while using two established erbium dental laser systems, a new CO2 laser system, and a conventional high-speed handpiece.

Methods: Eighty non-carious human extracted molars were separated into four sample groups of 20 teeth each. Three laser systems were used, respectively, to ablate the occlusal surface of the teeth in three of the groups for 60 seconds each. The high-speed handpiece was used to drill the occlusal surface of the fourth group for 60 seconds. Pulpal temperatures were measured using thermocouples inserted into each tooth's pulpal chamber prior to ablation.

Results: None of the average temperature increases approached the threshold of 5.5°C at which pulpal damage begins. On average, the pulpal temperature of teeth ablated with the Waterlase MD system increased the most (3.56°C). The traditional handpiece caused the lowest average temperature increase (1.57°C), followed by the LightWalker DT system (3.20°C) and the Solea CO2 system (3.30°C).