OBJECTIVETo evaluation the influences of lateral occlusal forces to stress distribution in filling material after the restorative therapy of wedge-shaped defect.

METHODSA three-dimensional finite element model of maxillary first premolar with wedge-shaped defect was established. The defect zone of the model with simulated glass ionomer was restored. Loads of different directions were applied on the model and stress analysis of restorative material were conducted.

RESULTSWhen the loading direction was parallel to the tooth long axis, restorative material unit subjected to relative small stress. When the loading direction was vertical to the cusp inclined plane, stress endured by restorative material unit was significantly increased, as the angle of loading inclination increased, the increase of stress became more pronounced.

CONCLUSIONAfter the restorative treatment of wedge-shaped defects in clinical, occlusal adjustment should be applied to reduce the inclination of cusp to relieve the lateral forces subjected by tooth so as to ease the stress burden of restorative material.