Abstract
OBJECTIVE: To systematically compare the bond strength of denture teeth and reline materials to additively manufactured (AM) versus subtractively milled (SM) denture base resins and to identify the material- and process-related factors influencing bonding performance. MATERIALS AND METHODS: A systematic electronic search of PubMed, Scopus, Embase, Web of Science, the Cochrane Library, and Google Scholar was conducted up to December 10, 2024. Eligible in vitro studies comparing bond strength at either the tooth-base or reline-base interface using AM and SM denture bases were included. Studies that lacked direct comparison, involved conventional heat-polymerized bases, or did not report quantitative bond strength data were excluded. Meta-analyses were performed using random-effects models, calculating mean differences (MD) for tooth bonding and standardized mean differences (SMD) for reline bonding. Subgroup, sensitivity, and publication bias analyses (Egger's regression and Begg's rank tests) were included. Risk of bias was evaluated using QUIN tools. RESULTS: Out of 2985 screened records, 20 studies comprising 156 independent comparisons were included; 41 for tooth bonding and 115 for reline bonding. Initial tooth-bonding meta-analysis revealed no significant difference; however, after exclusion of two outlier comparisons identified through sensitivity analysis (n = 39), milled bases demonstrated significantly higher bond strength (MD = -2.43 MPa, 95% CI-3.90 to -0.96; p = 0.001). For reline bonding, AM bases consistently underperformed across all studies, with the pooled estimate favoring milled bases (SMD = -2.62, 95% CI-3.22 to -2.03; p = 0.001). CONCLUSION: Within the limitations of this review, milled denture bases demonstrate consistently stronger and more reliable bonding to both teeth and reline materials than current printable photopolymer bases.