DDS Candidate, Class of 2023 University of Michigan School of Dentistry Palos park, Illinois, United States
Properly restoring endodontically treated teeth is essential to successful endodontics. However, there are some questions associated with the decision process around tooth restoration that remain unanswered. This study assessed the effects of type of restoration and tooth group involved in restorations of endodontically treated teeth. After IRB approval, a database with more than 2,000 cases containing crossed information between root canals completed and restorations placed in a university environment was analyzed. Only teeth with successful root canal treatment for at least one year were selected. Of these, 659 cases fulfilled the inclusion/exclusion criteria, with an average follow up of 4.8 years. Data was statistically analyzed by Fisher test and linear regression (p <.05). A total of 162 restorations failed (24.58%) after an average of 3.2 years. Crowns had the best outcome, with failure rates of 18.62%. Interestingly, closure of the endodontic access made in pre-existing crowns resulted in a failure rate of 17.86%, which is statistically similar to new crowns. The largest statistically significant failure rates compared to other groups were found on anterior teeth (43.9%) and direct restorations (46%). In conclusion, this study is the first to observe that restoring the access in an adequate crown provides the same success for the restoration as a new crown. In addition, within the limitations of a retrospective study with cases completed by dental students, it can be concluded that direct restorations fail more often than crowns.
