Role of cone-beam computed tomography in predicting root canal treatment success: A systematic review and meta-analysis

Root canal treatment (RCT) is an essential dental procedure aimed at preserving natural teeth by eliminating infected pulp and preventing reinfection. Predicting RCT success remains a clinical challenge due to anatomical complexities and diagnostic limitations of traditional 2D imaging. Cone-beam computed tomography (CBCT) offers three-dimensional visualization, potentially enhancing diagnostic accuracy and prognostic evaluation. This systematic review and meta-analysis aimed to evaluate the role of CBCT in predicting the success of RCT by identifying anatomical and pathological factors that influence treatment outcomes. This review is the first to separately synthesize diagnostic accuracy and prognostic evidence for CBCT in predicting non-surgical RCT outcomes using subgroup analyses of voxel size and follow-up duration. Following PRISMA guidelines, electronic databases including PubMed, Scopus, Web of Science, and Embase were searched for relevant studies published between 2013 and 2024. Studies were categorized as (1) diagnostic accuracy studies or (2) prognostic studies assessing whether CBCT-identified variables predicted RCT success/failure. Data extraction and quality assessment were performed using appropriate critical appraisal tools. Meta-analysis was conducted to determine pooled effect sizes for periapical lesion detection, root fracture identification, and canal configuration assessment. Twelve studies (6 diagnostic accuracy; 6 prognostic outcome) involving various designs and sample sizes were included. Meta-analysis of diagnostic accuracy studies showed pooled sensitivity/specificity of 0.88/0.84 for periapical lesions (I2 = 47%), 0.81/0.86 for vertical root fractures (I2 = 52%), and 0.91/0.88 for canal morphology (I2 = 28%). Prognostic meta-analysis demonstrated significant associations between CBCT-detected pathology and risk of post-treatment failure: periapical lesions (OR = 2.63; 95% CI 1.78-3.58; p 2 = 39%), root fractures (OR = 3.48; 95% CI 2.05-5.12; p 2 = 44%), and complex canal anatomy (OR = 1.94; 95% CI 1.20-2.82; p = 0.004; I2 = 28%). Subgroup analyses showed stronger prediction with voxel size < 0.2 mm and follow-ups ≥ 12 months. While CBCT demonstrates improved diagnostic capability and offers valuable prognostic insight in complex cases, its findings cannot establish causation and do not guarantee treatment success. CBCT should therefore be used selectively, considering its cost, radiation exposure, and the need for operator expertise.