Factors Predicting Endodontic Intervention in Non-Endodontically Treated Crowned Teeth

Objectives: Presently, no clinical criteria exist which clearly indicate or recommend elective root canal (RCT) prior to crowning of teeth. The aim of this study was to identify and qualify factors associated with an increased risk of RCT of a crowned tooth in order to identify teeth for which an elective RCT should be recommended before full crown coverage.
Methods: AxiUm dental software (Henry Schein, Coquitlam BC, Canada) was used to identify all single unit crowns placed between 2000-2018 at the University of Alberta School of Dentistry on non-endodontically treated teeth that later were endodontically treated or a RCT was recommended after crown cementation (‘cases’). Characteristics of these teeth were compared to matched ‘controls’ (crowned non-endodontically treated teeth with no need for endodontic intervention after crown cementation).
Results: Overall, 69 teeth were identified as ‘cases’. The minimum follow-up time was 0.04 years. The mean number of restorations prior to crown placement was significantly higher among ‘cases’ (2.16, SD=0.99) compared to ‘controls’ (0.78, SD=0.78) (p=0.008). The majority (65%, n=45) of teeth in the cases group, required the RCT during the first three years after crown cementation.
Conclusions: Within the limitation of this study, factors of interest such as presence of multiple restorations and extent of restorative history at the time of crown placement were identified. With further investigation, we aim to establish criteria and guidelines to predict high-risk cases in which an elective RCT will be recommended to avoid endodontic intervention after crown placement.