Finite Element Analysis in Polymer-Based Adhesive Dental Restorations: A Narrative Review on Material Behavior, Methodological Validity, and Clinical Relevance

Finite element analysis (FEA) is increasingly used in conservative and restorative dentistry to investigate the mechanical behavior of adhesive direct and indirect polymer-based restorations. Despite the growing number of FEA-based studies, the literature currently lacks a dedicated critical synthesis specifically addressing the methodological validity and clinical interpretability of FEA in adhesive restorative dentistry. This narrative review critically examines the current literature on the application of FEA in adhesive restorative dentistry, with particular attention to class I to class V cavities in anterior and posterior teeth restored with direct or indirect polymeric materials, including inlays, onlays, overlays, and tabletop restorations. A structured, non-systematic search of major databases was conducted, and selected studies were qualitatively appraised with emphasis on modeling assumptions, stress distribution, and clinical meaning. Unlike previous broad overviews of dental biomechanics, this review provides a clinically oriented framework for interpreting FEA findings across restorative strategies. FEA consistently identifies trends related to cavity configuration, cuspal support, restoration design, material stiffness, polymerization shrinkage, and adhesive interface behavior, helping to explain clinically observed failure patterns and supporting minimally invasive approaches. However, simplified material models, idealized bonding conditions, and static loading protocols limit prediction of long-term performance. When interpreted within these constraints and integrated with experimental and clinical evidence, FEA remains a valuable complementary tool for rational restorative decision-making.