ABSTRACT
Objective To investigate the stress distribution in various tooth heights of ferrule effect in post crown,and to evaluate the biomechanical mechanism in post crown.Methods The three-dimensional finite element entity grid model was constructed,which was a maxillary central incisor restored with post and porcelain fused to metal crown (PFM crown).By imitating the various tooth heights under static loading,the dentin stress was analyzed.Results The stress distribution had an increasing tendency from tooth cervix to root,but it could be decreased by ferrule structures and the decrease degree accorded with the region and height of ferrule.The ferrule effect of the wrapping 1 cm coronal tooth could decrease the stress of the tooth cervix obviously but 2 cm decreased a little.Conclusion The crown wrapping 1 cm coronal can produce ferrule effect obviously and protect the tooth.We can choose to use crown wrapping 2 cm coronal to care the tooth condition.