title: Influence of margin design and taper abutment angle on a restored crown of a first premolar using finite element analysis.
abstract: OBJECTIVE
  The purpose of this study was to determine the influence of margin design and taper abutment angle on the stresses developed in all-ceramic first premolar crowns.
  
  
  METHODS
  Four margin designs and three taper abutment angles were independently incorporated into models examined by finite element analysis. A 600-N force was applied vertically downward.
  
  
  RESULTS
  The taper abutment angle had a significant influence on the greatest peak tensile maximum principal stresses (sigma11) in the coping (16.8% change in stress for an 8-degree variation in taper angle). The margin design had significant influence on the highest peak tensile sigma11 in the dentin (60% difference in stress between designs) and lesser significance in the cement (30%). All calculated values of the highest peak tensile sigma11 were considerably lower than the fracture strengths of the respective materials in which the stresses resided.
  
  
  CONCLUSIONS
  A smaller taper abutment angle and a larger chamfer radius (equivalent to the modified light chamfer) are recommended to reduce the magnitude of the greatest peak tensile sigma11 based on the finite element modeling conducted.
authors.affiliation: School of Aerospace, Mechanical and Mechatronic Engineering, Faculty of Dentistry, Biomaterials Science Research Unit, National Innovation Centre, Eveleigh, New South Wales, Australia.
authors.forename: Kaarel A
authors.initials: KA
authors.lastname: Proos
authors.forename: Michael V
authors.initials: MV
authors.lastname: Swain
authors.forename: Jim
authors.initials: J
authors.lastname: Ironside
authors.forename: Grant P
authors.initials: GP
authors.lastname: Steven
mesh_terms: D001641:Bicuspid; D002516:Ceramics / Q000737:chemistry; D003198:Computer Simulation; D003442:Crowns; D000044:Dental Abutments; D003738:Dental Cements / Q000737:chemistry; D017267:Dental Prosthesis Design; D003804:Dentin / Q000502:physiology; D020342:Finite Element Analysis; D006801:Humans; D008954:Models, Biological; D013314:Stress, Mechanical; D013499:Surface Properties; D019228:Tooth Crown / Q000502:physiology; D019231:Tooth Preparation, Prosthodontic
chemical_list: D003738:Dental Cements