Effect of restoration material on stress distribution on partial crowns: A 3D finite element analysis

Abstract

Background/purpose Various restoration materials have been used to restore as onlay materials to restore highly defected molar teeth. Different mechanical and physical properties of these materials may affect the success or survival of the restoration. The purpose of this study was to evaluate the restoration materials effects on stress distribution. Materials and methods Three dimensional finite element analysis (FEA) was used to evaluate the stress concentrations and distributions at the restoration and the tooth. Maxillar first molar tooth constructed to evaluate the stress distribution and concentration levels at the restorations and the tooth structure. Two kinds of restoration materials, bulkfill composite and conventional hybrid composite was evaluated for direct method, while full ceramic and indirect composite was used for indirect method. A load of 200 N was applied on the restorations and stress levels were calculated by von Mises stress values. Results Highest stress concentration was observed at the ceramic restoration (3.77 GPa). Stress levels were 2.90 GPa for bulkfill composite and 2.14 GPa for direct and indirect composite. At the tooth structure the stress levels were 3.33 GPa, 3.18 GPa and 2.48 GPa for bulkfill, direct and indirect composites respectively. The lowest stress values was observed with the porcelain restoration (1.69 GPa). Stress concentrations at the adhesive system were 2.10 MPa for bulkfill composite, 1.35 MPa for direct and indirect composites and 1.25 Mpa for porcelain restoration. Conclusion The restoration material affects the stress levels at the restoration and the tooth while the stress concentration areas remained nearly the same.

Effect of Inlays, Onlays and Endocrown Cavity Design Preparation on Fracture Resistance and Fracture Mode of Endodontically Treated Teeth: An In Vitro Study

“…It has been reported that materials with low modulus of elasticity tend to absorb stress, concentrating it inside the material and not transferring it to the tooth structure. 31 Özkır found that fiber reinforcement improved the fracture resistance of composite resin. 32 In another study, Goracci et al 33 showed that the highest fracture toughness and flexural strength was recorded with EverX Posterior compared to other bulk fill and conventional resin compos-ites when their thickness was over 4 mm.…”

“…Recently, new types of composite resin materials have been introduced to replace the dentin and to absorb stress to minimize the risk of fracture. It has been reported that materials with low modulus of elasticity tend to absorb stress, concentrating it inside the material and not transferring it to the tooth structure 31 . Özkır found that fiber reinforcement improved the fracture resistance of composite resin 32 .…”

Effect of cavity design and material type on fracture resistance and failure pattern of molars restored by computer-aided design/computer-aided manufacturing inlays/onlays

“…[ 4 5 6 ] Particularly, modulus of elasticity has to be considered as high elastic modulus materials tend to accumulate stresses; while materials of low elastic modulus absorb stresses. [ 7 ] Therefore, Katana Zirconia (KZ) ML HT and CeraSmart (CS) as two ceramic materials of extremely different Elastic Modulus were suggested to study the difference in both material behavior under load.…”

Adhesive-Ceramic Interface Behavior in Dental Restorations. FEM Study and SEM Investigation

“…According to another FEA study performed on CAD-CAM ceramic restorations (IPS e.max CAD-on) and loaded on the occlusal and occlusal-vestibular surface, no significant differences were reported in the cement layer or between different preparation designs [ 32 ]. Özkir SE conducted his FEA study to determine the stress distributed on the tooth and onlay-type restorations made of integral ceramic and composite resin, reporting that the highest stress concentration was observed at the ceramic restoration (3.77 GPa) while the lowest value of stress was recorded on the tooth (1.69 GPa) [ 33 ]. Stress concentration sites indicate the likely onset of tooth failure and fracture.…”

“…Stress concentration sites indicate the likely onset of tooth failure and fracture. High elastic modulus materials (porcelain, for example) tend to accumulate high stresses but fail to transfer those stresses further to the tooth structure, and therefore avoid crown fractures [ 33 , 34 ].…”