Biomechanics in Endodontically Treated Teeth: Fibreglass Posts and Direct Restorations

Introduction: The purpose of this study was to determine, by a non-destructive method, the extent to which cusps are weakened by endodontic and restorative procedures. Methods: Fifty maxillary sound premolars were evaluated applying axial forces (range 98-294N) on their occlusal surface by the use of a mechanically controlled loading device inducing cuspal deflection while sophisticated Laser LTS twin sensor registered their cuspal movement. Cusp deflection values in micron were recorded for each tooth sequentially in intact condition and after conclusion of endodontic and restorative procedures (MOD cavity. Teeth were randomly divided in 10 groups (n =5) and restored with ten different materials as reported on Tab. 1. For all ten groups were evaluated: a) amount of cusps deflection; b) average stiffness; c) percentage structural recovery, in both intact and restored state. Results: Average stiffness in intact and restored status and percentage of structural recovery have been calculated for all experimental groups respectively. Results are reported on table below. Conclusions: Bonded composite restorations in endodontically treated teeth could be an appropriate way to afford good resistance to occlusal loads. It is important to highlight how the use of fibber glass posts and micro-hybrid composite materials in such restorations came out to be a suitable solution for structural recovery of the treated element. Concluding, direct composite techniques could guarantee an adequate aesthetic and structural recovery of endodontically treated elements.