[Estimation of biomechanical behavior in deep wedge-shaped defects restored by different methods under static and...

To analyze the biomechanical properties of the right mandibular second premolar with deep wedge-shaped defects under static and dynamic loads by finite element method, so as to select appropriate repair method in clinic.

To establish the deep wedge-shaped defect model of the right mandibular second premolar, the unrepaired model after root canal treatment was used as the control group, and resin filling (group A), resin filling after post restoration (group B), crown restoration after resin filling (group C), post and crown restoration after resin filling (group D) were used as the experimental groups. According to different materials, group B and group D were further divided into fiber post (B1, D1) group and pure Ti post (B2, D2) group. Static and dynamic loading were applied by three dimensional finite element analysis software, and the stress and strain were analyzed before and after restoration.

Compared with the control group, the stress values under static loading was much lower than that under dynamic loading. Von Mises and the maximum principal stress in each experimental group decreased significantly under static and dynamic loading. In the post group, the stress distribution of fiber post was more uniform than that of pure Ti post.

Dynamic load has great influence on the stress distribution. Full crown restoration is beneficial to the stress distribution of the teeth with deep wedge-shaped defects. If a post is necessary, fiber post should be selected.