Stress distribution in endodontically treated abfracted mandibular premolar restored with different cements and crowns: A three-dimensional finite element analysis

J Conserv Dent. 2018 Sep-Oct;21(5):557-561. doi: 10.4103/JCD.JCD_206_18.

Abstract

Context: Noncarious cervical lesions may penetrate the pulp and require root canal treatment followed by crown placement. Such teeth may be susceptible to fracture, especially at the cervical area.

Aims: To estimate which combination of restorative material and crown resulted in homogenous stress-strain distribution of endodontically treated abfracted mandibular premolar using three-dimensional finite element model (FEM).

Settings and design: A three-dimensional model of mandibular single-rooted premolar along with alveolar bone was created in finite element analysis (FEA) software preprocessor ANSYS rel 14.5 FEM software (ANSYS Inc., Houston, USA, 1994). Cervical lesion was created in the model with specific dimensions, 3 mm mesiodistally and 2 mm gingivoocclusally with enamel occlusal margin and dentin gingival margin.

Materials and methods: Tooth was simulated to be root canal treated and restored with different types of cements and crowns followed by placing a static load of 300 N at an angle of 135°. Analysis was run and stress distribution pattern was studied.

Results: Cervical region of an endodontically treated tooth is subjected to stresses, irrespective of restorative material used. Porcelain fused to metal (PFM) crowns showed least strain values with different postendodontic, restorative materials.

Conclusions: FEA is a predictable and reproducible model to predict stress-strain behavior. PFM crowns with different postendodontic restorative materials showed least strain values in the cervical area of abfracted, endodontically treated premolars.

Keywords: Noncarious cervical lesions; porcelain fused to metal restorations; postendodontic restorations; three-dimensional finite element analysis.