Three-dimensional Finite Element Analysis Of Dynamic Features And Fatigue Failure On The Maxillary Canine Root Canal With Various Profiles After Restoration Using Fiber Posts,and The Research Of 3D Printing Technology

Objective: To analyze the dynamics and fatigue failure mechanisms of the maxillary canine with normal or a funnel-shaped root canal restored by fiber posts using the 3D finite element analysis.To investigate the potential mechanism of fatigue failure during the teeth repairmen.To provide the rationale for the shelf life prediction and fatigue resistance after restoration using fiber posts.On this basis,to investigate the effect of different figurate root canal on the stress distribution of 3D printing post and core restored maxillary canine,and to provides theoretical basis for clinical.Methods:1.To obtain point cloud data of teeth model based on the three coordinate measuring machine to scan it.Using reverse engineering software Geomagic Studio to refactoring the point cloud data.And using CAD module of NX UG software to set up 3D model of restorations.2.Use pre fiber post to restore normal form root canal and the flared root maxillary canine.Based on the three dimensional finite element method to analysis the situation of the stress-strain for teeth restored by pre fiber post.Smith-Waston-Topper principal was utilized to predict the fatigue life of the teeth,while the fatigue failure was also analyzed.3.Use 3D printing post and pre fiber post to restore normal form root canal and the flared root maxillary canine.And based on the three dimensional finite element method to analysis and compare the stress situations of the root and post-core for different forms root canal tooth restored by two systems.Results:1.The fatigue resistance of the root canal with normal profile restored by the fiber posts was superior to that of the funnel-shaped root canal.The position of initial fatigue damage was similar to the position with the maximal principal stress.The threshold of the fatigue safety factors was coincidented with the transverse turning curve after repairment.In the presence of maximal strain,the line stretcher of the perpendicular line of the load was coincidented with the oblique turning curve after repairment.2.For normal figurate root canals,the stress distribution of 3D printing post and core system is better than that of pre fiber post system,and it can effectively reduce the failure probability of bond.For flared root canals,the stress distribution of 3D printing post and core system is better than that of pre fiber post system,and it can effectively increase the fracture resistance of teeth.Conclusions:1.The shelf life of the root canal with normal profile was higher than that of the funnel-shaped root canal restored by the fiber posts.The localization of the maximal principal stress restored by fiber posts was the fatigue region susceptible to the injury.The fatigue failure was mainly induced by the fatigue structural damage and extension of the fatigue crack.The possibility of transverse and oblique fold was not the same under various conditions.2.Whether normal figurate root canals or flared root canals,3D printing posts restored teeth are better than that of pre fiber post system.