Epidemiological evaluation of the outcomes of nonsurgical root canal treatment in a large cohort of insured dental patients.

Selected outcomes following initial nonsurgical root canal treatment (NSRCT) procedures were retrospectively assessed using an insurance company database of 110,766 nonsurgical root canal procedures that were completed by endodontists and their referring general dentists. A subset of 44,613 cases, with a minimum required follow-up time of 2 yr, showed incidences of extraction, retreatment and periradicular surgery equal to 5.56%, 2.47%, and 1.41%, respectively. The incidence of subsequent extraction increased with patient age. Teeth that were not restored after root canal therapy were significantly more likely to undergo extraction than restored teeth. Although the practice pattern for endodontists consisted of a significantly higher proportion of molars (48% more; p < 0.001) and a smaller proportion of anterior teeth (43% less; p < 0.001) than general dentists, both groups of providers had comparable rates of untoward events. These data strongly support the hypothesis that the specialist practice provides similar rates of clinical success compared with other providers, even when treating significantly more complex NSRCT cases. Overall, 94.44% of nonsurgical root canal treated teeth remained functional over an average follow-up time of 3.5 yr. These results are an important indication of the benefits of endodontic treatment when provided in an integrated health care delivery system of endodontists and their referring general dentists.