All amalgam post core repair the residual root and residual crown of the posterior tooth;

A study of the effect of root canal pin on increasing the strength of bending resistance of PFM crown abutment;

Objective: To evaluate the clinical of using prefabricated cylindrical root canal pin to lengthen the clinical crown and restoring anterior tooth and premolar defect with PFM.

Study of stress distribution in mandibular first premolar restored by composite resin with root screw of different length in different occlusion;