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

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.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.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.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.