Outcome and Survival of Endodontically Treated Cracked Posterior Permanent Teeth: A Systematic Review and Meta-analysis

Introduction: The aim of the present systematic review and meta-analysis was to evaluate the success and survival rate of endodontically treated cracked posterior teeth and to assess the preoperative factors that affect teeth survival. Methods: The study protocol was registered on the PROSPERO international prospective database of systematic reviews (CRD42019119091). Electronic search was performed for studies up to November 30, 2018 in the following databases: PubMed, Scopus, and Cochrane. All searches were done following the PRISMA guidelines. Clinical studies evaluating the success and/or the survival rate of cracked teeth that were endodontically treated with at least 1-year follow-up were selected. The Newcastle-Ottawa scale was used to evaluate risk assessment. Publication bias was evaluated with funnel plots, and the Egger's test was performed to test asymmetry. Results: From the 410 studies identified through the initial search, 7 studies qualified for the final analysis, all of which were longitudinal cohort studies. The results of the meta-analysis indicated a survival rate of 88% (confidence interval, 0.81-0.94) and a success rate of 82% (confidence interval, 0.78-0.86) after 1 year of follow-up. The presence of a periodontal pocket associated to a crack (relative risk, 1.11) resulted in a higher risk of tooth loss. Patient sex, tooth type, position, the number of cracks present, and preoperative pulp status did not affect treatment survival rate (P > .05). Most of the included studies did not have an accurate record of many variables that could affect the tooth survival. Plus, studies did not present extended follow-up periods or an adequate dropout rate to properly assess treatment outcome and survival. Conclusions: According to the results of the present systematic review and meta-analysis, root canal treatment in cracked posterior teeth can be considered a suitable treatment option. The presence of an associated periodontal pocket results in a lower survival rate.