Original Paper(Vol.55 No.12 pp.1060-1066)

Intensity of Singuler Stress Field due to Wedge-Shaped Defect in Human Tooth after Restored with Composite Resins

Nao-Aki NODA, Ker-Kong CHEN, Kiyoshi TAJIMA, Hiromi IMOTO and Takuya TSUTSUMI

Abstract:Wedge-shaped defects are frequently observed on the cervical region of the human tooth. Previously, most studies explained that improper toothbrushing causes such defects. However, recent clinical obsarvation suggested that the repeated stress due to occlusal force may induce the formation of these wedge-shaped defects. In this study, a two-dimensional human tooth model after a wedge-shaped defect is restored with the composite resin is analyzed by using the finite element method. To obtain the intensity of the singular stress field accurately, a method of analysis is discussed for calculating generalized stress intensity factors, which control the singular stress around the tip of the defect. Then, the relationships between the stress intensity and occlusion are discussed.

Key Words:Elasticity, Biomechanics, Fracture mechanics, Finite element method, Wedge-shaped defect, Human tooth