This study aimed to evaluate the stress distribution that results from temperature changes in teeth restored with gold inlay and to predict the fatigue life of the teeth. A thermal load regimen for finite element analysis (FEA) was established in an in vivo experiment, in which participants with gold inlays drank hot and cold water. An extracted human maxillary molar was converted into a 3D FEA model. The tooth models with Class I and II preparations were restored with gold inlay in the experimental groups. The stress distribution was analyzed under the thermal loads. Also, lifetime prediction was conducted using Basquin's formulation. The gold inlay groups showed a higher stress distribution than the preparation-only groups regardless of the type of preparation. The Class II gold inlay group showed the shortest fatigue life of 2.48×1011 cycles, whereas the Class I preparation group showed the longest fatigue life of 4.49×1016 cycles.
Keywords: Finite element analysis; Lifetime prediction; Thermal stress; Tooth crack.