Non-surgical root canal treatment and retreatment versus apical surgery in treating apical periodontitis: A systematic review

Background: In addition to non-surgical root canal treatment or retreatment, apical surgery may be carried out to manage teeth with apical periodontitis. However, it is unclear which treatment option is more effective. Objective: To systematically review the effectiveness of apical surgery compared with non-surgical treatment or retreatment in terms of clinical and patient-related outcomes in teeth with apical periodontitis. Methods: A literature search of electronic databases, the grey literature, the reference lists of included articles and previous reviews, and a hand search of leading endodontic journals, was conducted. Randomised and non-randomised control trials, and longitudinal observational studies on patients undergoing surgical (treatment group) and non-surgical root canal treatment or retreatment (control group) of teeth with apical periodontitis were included. The risk of bias was appraised using the Cochrane risk-of-bias tool; ROBINS-I and the Newcastle-Ottawa Scale. Results: Five studies, consisting of two randomised clinical trials, two non-randomised clinical trials, and a retrospective cohort study, were included. The interobserver agreement was high and kappa correlation coefficient was good. In total 529 teeth were available for follow-up that varied from 6 months to 8.7 years. The overall risk of bias was high for four studies and raised some concerns in one study. Apical surgery showed seemly better results regarding periapical healing and less need for more and further intervention, although tooth survival was higher in the control group. Given the heterogeneity of the studies, meta-analysis was not possible. Discussion: Previous systematic reviews have conducted an indirect comparison by separately pooling the outcomes of studies analysing either non-surgical, or surgical, treatment. In this systematic review, only studies that compared both treatments were included. Most results of this and previous reviews were similar. Conclusion: No treatment option showed clear superiority. However, to arrive at statistically supported conclusions there is a need for additional high-quality comparative trials. Registration: PROSPERO database (Registration number CRD42021260300).