Stress distribution in premolars restored with inlays or onlays: 3D finite element analysis

Abstract

PURPOSETo analyze stress distribution in premolars restored with inlays or onlays using various materials.MATERIALS AND METHODSThree-dimensional maxillary premolar models of abutments were designed to include the following: 1) inlay with O cavity (O group), 2) inlay with MO cavity (MO group), 3) inlay with MOD cavity (MOD group), and 4) onlay (ONLAY group). A restoration of each inlay or onlay cavity was simulated using gold alloy, e.max ceramic, or composite resin for restoration. To simulate masticatory forces, a total of 140 N static axial force was applied onto the tooth at the occlusal contact areas. A finite element analysis was performed to predict the magnitude and pattern of stresses generated by occlusal loading.RESULTSMaximum von Mises stress values generated in the abutment teeth of the ONLAY group were ranged from 26.1 to 26.8 MPa, which were significantly lower than those of inlay groups (O group: 260.3–260.7 MPa; MO group: 252.1–262.4 MPa; MOD group: 281.4–298.8 MPa). Maximum von Mises stresses generated with ceramic, gold, and composite restorations were 280.1, 269.9, and 286.6 MPa, respectively, in the MOD group. They were 252.2, 248.0, 255.1 MPa, respectively, in the ONLAY group.CONCLUSIONThe onlay design (ONLAY group) protected tooth structures more effectively than inlay designs (O, MO, and MOD groups). However, stress magnitudes in restorations with various dental materials exhibited no significant difference among groups (O, MO, MOD, ONLAY).

Four-year follow-up of increased vertical dimension of occlusion using resin composites

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Young’s modulus and Poisson ratio of composite materials: Influence of wet and dry storage

“…3). Locally stresses due to occlusal forces will occur in the posterior region, which exceeds these stresses as has been demonstrated by Yang et al 25) . The found stresses were >250 MPa for a composite with a Young's modulus of 9.5 GPa, comparable with APX after a load of 150 MPa, before this load the stresses will be still higher due to the higher Young's modulus.…”

Investigating inlay designs of class II cavity with deep margin elevation using finite element method

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