title: Biomechanics of cervical tooth region and noncarious cervical lesions of different morphology; three-dimensional finite element analysis.
abstract: OBJECTIVE
  The present study aims to investigate the influence of presence and shape of cervical lesions on biomechanical behavior of mandibular first premolar, subjected to two types of occlusal loading using three-dimensional (3D) finite element method (FEM).
  
  
  METHODS
  3D models of the mandibular premolar are created from a micro computed tomography X-ray image: model of sound mandibular premolar, model with the wedge-shaped cervical lesion (V lesion), and model with saucer-shaped cervical lesion (U lesion). By FEM, straining of the tooth tissues under functional and nonfunctional occlusal loading of 200 (N) is analyzed. For the analysis, the following software was used: CTAn program 1.10 and ANSYS Workbench (version 14.0). The results are presented in von Mises stress.
  
  
  RESULTS
  Values of calculated stress in all tooth structures are higher under nonfunctional occlusal loading, while the functional loading is resulted in homogeneous stress distribution. Nonfunctional load in the cervical area of sound tooth model as well as in the sub-superficial layer of the enamel resulted with a significant stress (over 50 [MPa]). The highest stress concentration on models with lesions is noticed on the apex of the V-shaped lesion, while stress in saucer U lesion is significantly lower and distributed over wider area.
  
  
  CONCLUSIONS
  The type of the occlusal teeth loading has the biggest influence on cervical stress intensity. Geometric shape of the existing lesion is very important in the distribution of internal stress. Compared to the U-shaped lesions, V-shaped lesions show significantly higher stress concentrations under load. Exposure to stress would lead to its progression.
authors.affiliation: Department of Restorative Dentistry and Endodontics, School of Dentistry, University of Sarajevo, Sarajevo, Bosnia and Herzegovina.
authors.forename: Selma
authors.initials: S
authors.lastname: Jakupović
authors.affiliation: Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Zagreb, Croatia.
authors.forename: Ivica
authors.initials: I
authors.lastname: Anić
authors.affiliation: Department of Prosthodontics, School of Dentistry, University of Sarajevo, Sarajevo, Bosnia and Herzegovina.
authors.forename: Muhamed
authors.initials: M
authors.lastname: Ajanović
authors.affiliation: Department of Restorative Dentistry and Endodontics, School of Dentistry, University of Sarajevo, Sarajevo, Bosnia and Herzegovina.
authors.forename: Samra
authors.initials: S
authors.lastname: Korać
authors.affiliation: Department of Restorative Dentistry and Endodontics, School of Dentistry, University of Sarajevo, Sarajevo, Bosnia and Herzegovina.
authors.forename: Alma
authors.initials: A
authors.lastname: Konjhodžić
authors.affiliation: Department of Restorative Dentistry and Endodontics, School of Dentistry, University of Sarajevo, Sarajevo, Bosnia and Herzegovina.
authors.forename: Aida
authors.initials: A
authors.lastname: Džanković
authors.affiliation: Department of Dental Morphology with Dental Anthropology and Forensics, Faculty of Dentistry, University of Sarajevo, Sarajevo, Bosnia and Hercegovina.
authors.forename: Amra
authors.initials: A
authors.lastname: Vuković
keywords: Abfraction; finite element method; noncarious cervical lesions; occlusion; stress