This in vitro study investigated the temperature changes experienced during electric welding of titanium to determine if the welding heat presented a potential danger to pulpal vitality. Welds were applied to cast titanium simulations of a three-unit fixed partial denture containing two thermocouples measuring temperature changes. Mean maximal temperature changes were 127.4 degrees F near the weld and 68.6 degrees F at the axial wall. The mean times for the temperature to drop to within 10.0 degrees F of starting temperature ranged from 84.1 to 133.7 seconds. The relatively low temperatures recorded in this study suggest that further investigation is warranted into the use of the welder intraorally.