Abstract:

Objective To compare the stress difference of the resin with different thicknesses in the screw access hole using three-dimensional finite element method. Methods A three-dimensional finite element model of the implant at the site of the mandibular first molar was established by computer aided design (CAD) software. A static load of 200 N was applied to the resin models with different thicknesses(1, 2, 3, 4, 5 mm) to analyze the effect of thickness on the von Mises stress and shear stress of the resin. Results In a certain range, the maximum von Mises stress and the maximum shear stress of the resin decreased with the increase of the thickness. At the thickness of 1mm, the maximum von Mises stress and shear stress of the resin were 23.85 MPa and 11.82 MPa, respectively. When the thickness was 2 mm, the maximum von Mises stress and shear stress of the resin were 18.75 MPa and 9.73 MPa respectively. At the thickness of 3 mm, the maximum von Mises stress and shear stress of the resin were 17.46 MPa and 9.04 MPa, respectively. When the thickness of the resin was more than 3 mm, the stress on it was in a stable level trend. When the thickness was 4 mm, the maximum von Mises stress and shear stress of the resin were 17.38 MPa and 9.04 MPa, respectively. When the thickness was 5 mm, the maximum von Mises stress and maximum shear stress of the resin were 17.18 MPa and 8.85 MPa, respectively. Conclusion When the resin reaches a certain thickness, the stress is small and stable. This study provides a new design strategy for reducing the complications after implant restoration caused by stress fatigue of the resin.

Key words: screw approach hole, hole sealing resin, three-dimensional finite element method