Initial root canal treatment and the replacement of a single tooth with an implant are both viable treatment options, but various success rates have been reported for each treatment modality. This retrospective study compared 196 implant restorations and 196 matched initial nonsurgical root canal treatment (NSRCT) teeth in patients for four possible outcomes: success, survival, survival with subsequent treatment intervention and failure. Cross classifications/tabulations were analyzed using Pearson's chi2 test for association of the two classifications (endodontic vs implant and outcome). Polytomous regression with likelihood ratio tests were used in testing association with tooth location and outcome. Outcomes were as follows for implants and NSRCT respectively: success 73.5% and 82.1%; survival with no intervention 2.6% and 8.2%; survival with intervention 17.9% and 3.6%; and failure 6.1% and 6.1%. Location of the restoration in the mouth did not affect outcome. This study suggests that restored endodontically treated teeth and single tooth implant restorations have similar failure rates, although the implant group showed a longer average and median time to function and a higher incidence of postoperative complications requiring subsequent treatment intervention.