The use of Endodontically-treated Teeth as Abutments for Fixed-partial Dentures

Methods: Three-dimensional (3D) FEA mathematical models were created to simulate fixed-partial denture (FPD) with the following nine different abutment configurations; 1: Natural (N)canine-(N)premolar, 2: Root-filled (RF)canine-(N)premolar, 3: (N)canine-(RF)premolar, 4: (RF)canine-(RF)premolar, 5: fibre-post-restored (FPR)canine-(N)premolar, 6: (N)canine-(FPR)premolar, 7: (FPR)canine-(FPR)premolar, 8: (N)canine-(FPR)premolar, 9: (FPR)canine-(N)premolar. Vertical occlusal load (300N-at centric occlusion position) was applied on three units of FPD. Solidworks/Cosmoworks structural analysis programs were used for FEA. The stress distributions and amounts were calculated according to the von Mises stres criteria.

Results: Stress values observed in the canine tooth models were more than the values observed in the premolar tooth models (57.74-66.44/63.81-78.15MPa). Although the mean mathematical stress values were similar to the each other in nine conditions (2.02-2.90MPa for premolar models; 2.59-3.48MPa for canine models), the localizations of the stresses among the abutment teeth were different. Root-canal-treatment increased the stress at the coronal region and FPR increased the stress at root dentin of canine tooth model. In premolar tooth models both root-canal-treatment and FPR increased the stress at root dentin.

Conclusions: Canine tooth received more stresses in any conditions when used as an abutment for a FPD with three units. The stress accumulation at the coronal region of the canine tooth is increased with the endodontic treatment and stresses at root dentin of premolar tooth were increased with the fiber-post restoration.