How durable are 3D-printed dental resin-based composites? An umbrella review

To assess the current evidence from systematic reviews and meta-analyses on the performance and potential durability of 3D-printed dental resin-based composites by synthesizing data on their mechanical, dimensional, optical, chemical, and clinical behavior, including available long-term outcomes, and by contrasting these findings with those of conventional and CAD/CAM-milled materials when applicable.

Searches in PubMed/MEDLINE, Scopus, and Web of Science were conducted from database inception to November 2025 to identified systematic reviews evaluating polymer-based dental materials fabricated using 3D-printing technologies (SLA, DLP, LCD). Two reviewers independently performed study selection, data extraction, and AMSTAR-2 assessment. Primary-study overlap was examined through a citation matrix, Corrected Covered Area (CCA), and heatmap visualization. Owing to substantial heterogeneity across materials, technologies, and testing protocols, results were narratively synthesized across mechanical, dimensional, optical, chemical, and clinical domains.

Fourteen reviews were included. Methodological quality varied considerably: only two achieved high confidence in AMSTAR-2, whereas most were rated low or critically low. The 221 study occurrences represented 182 unique studies, resulting in a CCA of 21.4 %, indicating moderate-to-high overlap with clusters centered on mechanical and dimensional outcomes. Across reviews, 3D-printed resins generally exhibited lower flexural strength, elastic modulus, fatigue resistance, and color stability, as well as higher sorption/solubility, than milled CAD/CAM materials. Dimensional accuracy and marginal/internal fit were typically within clinically acceptable limits but showed strong dependence on washing procedures, curing protocols, and printing orientation. Short-term clinical evidence (6-24 months) demonstrated encouraging performance for inlays, onlays, overlays, crowns, and veneers, but remains insufficient to support conclusions about true long-term behavior.

3D-printed resins are viable options for provisional and selected indirect restorations, showing acceptable short-term performance. However, their long-term durability remains uncertain, and CAD/CAM-milled materials continue to offer superior mechanical and optical stability. Well-designed clinical trials and standardized laboratory protocols are needed to support reliable long-term recommendations.

3D-printed dental resins exhibited inferior mechanical and optical stability compared with CAD/CAM-milled materials which limits their current indication for long-term definitive restorations.