Won K, Berlin-Broner Y. Factors associated with the need for a primary endodontic treatment after a single unit crown cementation: a retrospective case-control study. J Endod 2022; DOI: 10.1016/j.joen.2022.02.001.

...the more likely to need endodontic treatment within three years.

Teeth requiring crowns frequently have an extensive dental history, being already heavily restored, and may have a stressed pulp, leading to a high likelihood for the need of endodontic treatment later. Endodontic treatment through a crown may be challenging due to altered crown morphology.

This case-control study identified all non-endodontically treated teeth which were crowned in 20 years from January 1999 (n = 5,677) at the School of Dentistry, Alberta, Canada. Cases were identified as those teeth which received subsequent endodontic treatment (n = 69). Controls (n = 69) were matched by age of subject and tooth.

Cases had a significantly higher mean number of restored surfaces prior to crown placement, and those with three or more restored surfaces had a six times higher risk for endodontic treatment than the controls. The mean time for a tooth requiring intervention was 3.85 years, with 25% requiring treatment within a year of crown placement.