Relatively few long-term studies have been performed to evaluate the clinical success of one-appointment pulpectomies in primary molar teeth. The purpose of this retrospective study was to evaluate the radiographic appearance of nonvital primary molars before and after treatment with a one-appointment formocresol pulpectomy technique. The mean length of time since pulpectomy treatment for the 62 primary molars was 40.2 months. Based upon strict radiographic criteria, the one-appointment pulpectomy procedure was considered to be successful in 82.3% (51) of the cases, with 3.2% (2) of pulpectomized primary molars needing retreatment, and 14.5% (9) of pulpectomy procedures failing. The pulpectomy procedure is indicated when inflammation of the pulpal tissue extends into the root canals, and possibly involves the periapical and/or bifurcation areas. This procedure provides an alternative to extraction and space maintenance when the pediatric dentist encounters a nonvital primary molar tooth.