Endodontic care, provided by 3,402 dental offices, was assessed from claims data maintained by the Washington Dental Service for 1999. Approximately 5.7 million dental procedures were provided to 880,317 patients by 2,796 general practitioners, 105 endodontists, and 494 other specialists. Of all dental services, 63,321 (1%) were endodontic procedures involving 52,911 (6%) patients. General dentists, endodontists, and other specialists performed 64.7%, 33.7%, and 1.6% of endodontic procedures, the majority of which were root canal therapy. The most frequent tooth types treated by root canal therapy were mandibular first molars (17.0%), maxillary first molars (15.2%), mandibular second molars (11.8%), maxillary second bicuspids (10.3%), maxillary second molars (9.1%), maxillary central and lateral incisors (8.8%), and mandibular second bicuspids (8.0%). Direct and indirect pulp caps by generalists and conventional retreatment and surgical therapy by endodontists made up the majority of the remaining endodontic services. Men had a greater procedure rate than women for most endodontic procedures.