Biomechanical Evaluation of CAD/CAM Inlay Restorations Through Experimental Flexural Strength Testing and Finite Element Analysis
Source abstract
Abstract
Background: This study aimed to investigate the biomechanical behavior of conservative inlay restorations fabricated from different CAD/CAM materials by combining experimental flexural strength testing with finite element analysis. Methods: Five CAD/CAM materials were evaluated: feldspathic ceramic (Cerec Blocs), leucite-reinforced ceramic (IPS Empress CAD), resin nano-ceramic (Lava Ultimate), polymer-infiltrated ceramic network (VITA Enamic), and lithium disilicate ceramic (IPS e.max CAD). Young’s modulus and Poisson’s ratio were experimentally determined using three-point bending and nanoindentation tests and used as inputs for 3D FEA. Von Mises (VM) stress distributions within the inlays were analyzed under simulated occlusal loading. Results: Maximum VM stresses showed an inverse relationship with material elasticity. IPS e.max CAD exhibited the highest maximum VM stress (45.571 MPa), whereas the resin nano-ceramic showed the lowest (25.419 MPa). Despite higher stress concentrations in high-modulus ceramics, VM values for all materials remained well below their FS limits. Conclusions: All materials demonstrated adequate mechanical stability under physiological loading. Lithium disilicate showed a comparatively larger margin between stress levels and flexural strength, while lower-modulus materials tended to promote greater stress transfer to supporting structures.
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Research context
OpenAlex topics: Dental materials and restorations · Endodontics and Root Canal Treatments · Bone Tissue Engineering Materials
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Restorative Treatment, Faculty of Dentistry, Atatürk University, 25240 Erzurum, Türkiye
Department of Restorative Treatment, Faculty of Dentistry, Sakarya University, 54100 Sakarya, Türkiye
Department of Mechanical Engineering, Karadeniz Technical University, 61080 Trabzon, Türkiye
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