Stress concentration in bone tissues and screw dental implants

Analysis of stress concentration in bone tissues and screw dental implants was performed on a model of screw join of the implant and surrounding bone tissues under the action of normal and tangential loads. The computations were performed by the boundary element method for the plane strain state. It was assumed that those hollows in the spongy bone, which had formed in the bone after the implant insertion, are conformed to the screw thread on the implant. Bone tissues are considered as an isotropic and homogeneous linear-elastic materials. It has been found that with the increasing in the spongy bone tissue elastic modulus, the maximum equivalent stresses in this bone tissue increase. Stresses in the cortical bone tissue decrease with the increasing in the spongy bone elastic modulus due to the decreasing in the load transferred to this bone part. Stresses in the spongy bone decrease with the increasing of the cortical bone layer elasticity modulus. The level of maximum stress in the cortical layer of the bone increases with the increasing of this bone tissue elastic modulus. The maximum of stresses in the cortical bone tissue are observed near the implant neck.