title: Influence of buccal cusp reduction when using porcelain laminate veneers in premolars. A comparative study using 3-D finite element analysis.
abstract: OBJECTIVE
  Based on a maxillary premolar restored with laminate veneer and using the 3-D finite element analysis (FEA) and μCT data, the aim of this study was to evaluate the influence of different types of buccal cusp reduction on the stress distribution in the porcelain laminate veneer and in the resin luting cement layer.
  
  
  METHODS
  Two 3-D FEA models (M) of a maxillary premolar were built from μCT data. The buccal cusp reduction followed two configurations: Mt - buccal cusp completely covered by porcelain laminate veneer; and Mp - buccal cusp partially covered by porcelain laminate veneer. The loading (150 N in 45°) was performed on the top of the buccal cusp. The finite element software (Ansys Workbench 10.0) was used to obtain the maximum shear stress (τ(max)) and maximum principal stress (σ(max)).
  
  
  RESULTS
  The Mp showed reduced the stress (σ(max)) in porcelain laminate veneer (from -2.3 to 24.5 MPa) in comparison with Mt (from -5.3 to 27.4 MPa). The difference between the peak and lower stress values of σ(max) in Mp (-6.8 to 26.7 MPa) and Mt (-5.3 to 27.4 MPa) was similar for the resin luting cement layer. The structures not exceeded the ultimate tensile strength or the shear bond strength.
  
  
  CONCLUSIONS
  Cusp reduction did not affect significant increase in σ(max) and τ(max). The Mt showed better stress distribution (τ(max)) than Mp.
authors.affiliation: Institute Federal of Parana, Londrina, Parana, Brazil.
authors.forename: Carlos Marcelo
authors.initials: CM
authors.lastname: Archangelo
authors.forename: Eduardo Passos
authors.initials: EP
authors.lastname: Rocha
authors.forename: Rodolfo Bruniera
authors.initials: RB
authors.lastname: Anchieta
authors.forename: Manoel
authors.initials: M
authors.lastname: Martin
authors.forename: Amilcar Chagas
authors.initials: AC
authors.lastname: Freitas
authors.forename: Ching-Chang
authors.initials: CC
authors.lastname: Ko
authors.forename: Paolo M
authors.initials: PM
authors.lastname: Cattaneo
mesh_terms: D001641:Bicuspid / Q000502:physiology*; D001840:Dental Bonding; D003776:Dental Porcelain; D003799:Dental Stress Analysis; D003801:Dental Veneers; D020342:Finite Element Analysis; D006801:Humans; D019279:Resin Cements; D013314:Stress, Mechanical; D013718:Tensile Strength
chemical_list: D019279:Resin Cements; D003776:Dental Porcelain