The influence of occlusal loads on stress distribution of cervical composite resin restorations: A three-dimensional finite element study

Abstract

The purpose of this study was to investigate the influence of various occlusal loading sites and directions on the stress distribution of the cervical composite resin restorations of maxillary second premolar, using 3 dimensional (3D) finite element (FE) analysis. Extracted maxillary second premolar was scanned serially with Micro-CT (SkyScan1072; SkyScan, Aartselaar, Belgium). The 3D images were processed by 3D-DOC-TOR (Able Software Co., Lexington, MA, USA). HyperMesh (Altair Engineering, Inc., Troy, USA) and ANSYS (Swanson Analysis Systems, Inc., Houston, USA) was used to mesh and analyze 3D FE model. Notch shaped cavity was filled with hybrid (Z100, 3M Dental Products, St. Paul, MN, USA) or flowable resin (Tetric Flow, Vivadent Ets., FL-9494-Schaan, Liechtenstein) and each restoration was simulated with adhesive layer thickness (40 ㎛). A static load of 200 N was applied on the three points of the buccal incline of the palatal cusp and oriented in 20�increments, from vertical (long axis of the tooth) to oblique 40�direction towards the buccal. The maximum principal stresses in the occlusal and cervical cavosurface margin and vertical section of buccal surfaces of notch-shaped class V cavity were analyzed using ANSYS. As the angle of loading direction increased, tensile stress increased. Loading site had little effect on it. Under same loading condition, Tetric Flow showed relatively lower stress than Z100 overall, except both point angles. Loading direction and the elastic modulus of restorative material seem to be important factor on the cervical restoration. [J Kor Acad Cons Dent 33(3):246-257, 2008]

Finite element analysis of maxillary central incisors restored with various post-and-core applications

“…Actually, in a living organism, the response to these structures to stress is more complex, For instance, it is well described that cortical bone of the mandible is transversely isotropic and inhomogeneous 18) . In addition, the stress distribution patterns simulated may be different depending on the materials and properties assigned to each layer of the model and the model used in the experiments 19,20) . Thus, the inherent limitations in this study should be considered.…”