Abstract: Dental or endodontic instruments such as drills, files, rasps, broaches, reamers, and the like are arranged to allow radiation of electromagnetic energy into a man-made or natural cavity in the tooth under treatment. The energy may be in the form of microwave or radio-frequency (RF) radiation. The energy raises the temperature of the surrounding tooth material, which tends to disinfect the material as a direct consequence of the temperature. Also, if a disinfectant material is additionally introduced into the tooth cavity, the temperature of the disinfectant material itself may be raised, which enhances its activity. In the particular application to the removal of degenerated pulp, the instrument may be introduced, and electrical or electromagnetic power applied to coagulate the pulp about the instrument, allowing more complete removal of the pulp. The dental instrument may be used with an RF energy delivery system for application of particular amounts of energy per unit time (power).