Effect of guided tissue regeneration on the success of surgical endodontic treatment of teeth with endodontic-periodontal lesions: A systematic review

Background: Endodontic-periodontal lesions may need surgical approach and the application of guided tissue regeneration (GTR) to be treated by a combined approach. Objectives: The aim of the present study was to evaluate the effects of GTR on the success (clinical and radiological healing) of teeth with endodontic-periodontal lesions treated by modern surgical endodontic treatment, by means of a systematic review of the literature. Methods: An exhaustive electronic (Medline, Embase and Scopus searched from inception to August 2020) and manual literature search combined with strict inclusion and exclusion criteria was undertaken to identify any clinical (prospective case series or comparative trials) studies that assessed the added benefit of GTR in modern surgical endodontic treatment of teeth with endodontic-periodontal lesions. The success of the treatment was assessed based on radiographic healing and clinical evaluations. The risk of bias of the identified studies was evaluated using the Cochrane's collaboration RoB 2.0 tool and the Joanna Briggs Institute (JBI) critical appraisal tools. Results: A systematic literature search for eligible reports retrieved three randomized controlled trials (RCTs) and one prospective single arm study with a total of 125 teeth in 125 subjects. One of the RCTs has a low risk of bias, while the other two raised some concerns, using the RoB 2.0 tool. Due to the heterogeneity of the results, it was not possible to perform a comparative meta-analysis and the results are presented in a narrative manner and by calculating pooled outcomes. Pooling together the data from all the included studies, the reported outcome was of complete healing in 58.4% of all cases, of scar tissue formation/incomplete healing in 24% of cases, of uncertain healing in 12.8% of cases, and of failure in 4.8% of all analysed teeth, with a follow-up ranging from 12 to 60 months. Discussion: The scientific evidence about the use of GTR in modern surgical endodontic treatment of endodontic-periodontal lesion is sparse, and the available results are derived from very heterogeneous studies, thus not permitting to clarify which is the most effective treatment option in these cases. Conclusions: There is an absence of studies comparing GTR versus no GTR. Registration: The protocol for this review was registered in the PROSPERO database with the registration ID number CRD42022300470.