title: Stress distribution with different restorations in teeth with curved roots: a finite element analysis study.
abstract: BACKGROUND
  The aim of this study was to investigate and compare stress distribution in various degrees of curved roots with different post and restorations by finite element analysis (FEA).
  
  
  METHODS
  Sixteen 3-dimensional FEA models were created and adapted by using computer software based on external anatomy of mandibular second premolar. A 50-N load was applied. Tensile and compressive stresses were plotted.
  
  
  RESULTS
  The stress distribution pattern showed that degrees of root curvature in this study (15, 30, and 45 degrees) had little effect. When the elastic modulus of post and core materials was similar to that of root dentin, tensile stresses were low and concentrated on the external root surface. With higher elastic modulus of materials, tensile stresses were increased and concentrated on the post and post apex.
  
  
  CONCLUSIONS
  Within the limitations of this study, the suitable restoration in endodontically treated mandibular premolar with limited loss of tooth structure was resin composite that was filled in the coronal third of the root canal. However, when the post and core were indicated, the glass-fiber post and resin composite core were the materials of choice for restoration.
authors.affiliation: Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Chayanee
authors.initials: C
authors.lastname: Chatvanitkul
authors.forename: Veera
authors.initials: V
authors.lastname: Lertchirakarn
mesh_terms: D001641:Bicuspid; D003188:Composite Resins; D003198:Computer Simulation; D003442:Crowns; D003722:Dental Alloys; D003793:Dental Restoration, Permanent / Q000379:methods*; D003799:Dental Stress Analysis / Q000379:methods*; D055119:Elastic Modulus; D020342:Finite Element Analysis; D005898:Glass; D006801:Humans; D008334:Mandible; D016876:Metal Ceramic Alloys; D008954:Models, Biological; D011176:Post and Core Technique; D013718:Tensile Strength; D014092:Tooth Root / Q000033:anatomy & histology*
chemical_list: D003188:Composite Resins; D003722:Dental Alloys; D016876:Metal Ceramic Alloys; C009753:fiberglass