Three-dimensional finite element analysis of fixed restoration of hemi-sectioned mandibular second molar

Objective To evaluate the mechanical behavior of the abutment teeth of the fixed restoration after the mandibular second molar being sectioned. Methods Finite element method was employed to investigate the stress distribution around the reserved distal or mesial root of the second mandibular molar after restored with fixed prosthesis of various designs. The model of combined crowns of 76 and missing 7 restored with 6 supported cantilever fixed bridge were designed as control. The same oblique load was applied on the occlusal surfaces of the molars, the stress distribution was analyzed. Results The stress status of the reserved distal root of 7 combined 6 is similar to the combined crowns of 76 , with the stress intensity slightly higher; The stress around the reserved mesial root of 7 combined 6 is significantly higher than the combined crowns of 76 , the stress concentration exhibited in the apical regions, instead of in the cervical regions, but the stress distribution was more favorable than 6 supported cantilever fixed bridge. Conclusion For the various prosthetic designs for hemi-sectioned 7 , the stress status of the fixed prosthesis reserving the distal root of 7 is more favorable than that of reserved mesial root of 7 . However, that latter is also an alternative to avoid missing 7 , on condition that the indication is strictly commanded.