Comparative evaluation of obturation techniques for C-shaped canals: a network meta-analysis.

OBJECTIVE: To compare the filling quality of different root canal filling methods in C-shaped canals using a network meta-analysis. MATERIALS AND METHODS: This PROSPERO-registered study [CRD420251044833] included in vitro investigations on C-shaped canals. After screening 1139 records, 9 studies were eligible. A Bayesian model network meta-analysis was performed using R software, with interventions ranked by SUCRA values. Risk of bias was assessed using the RoBDEMAT tool, and subgroup analyses were conducted for different canal configurations and imaging methods. RESULTS: No statistically significant differences were found between LC and any of the other filling method, with the exception that UC exhibited significantly lower porosity than LC at the middle region(MD = -1.7,95% Crl:-3.3, -0.062). Subgroup analyses revealed that the overall results were modified to some extent by differences in C-shaped canal anatomy and the method used to detect obturation porosity. CONCLUSIONS: Current obturation techniques remain unable to achieve completely void-free filling in C-shaped root canals. However, the obturation performance of the same technique varied across different root levels, suggesting a site-dependent pattern of filling quality. CLINICAL RELEVANCE: The present findings do not support a definitive recommendation for any particular obturation technique in clinical practice. Rather, they may be viewed as an evidence map that provides a reference framework for the design of future studies. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/prospero, CRD420251044833.