title: Influence of tooth preparation design on the stress distribution in maxillary central incisors restored by means of alumina porcelain veneers: a 3D-finite element analysis.
abstract: OBJECTIVE
  The present study aimed at providing 3D-FEA engineering tools for the understanding of the influence of tooth preparation design on the stress distribution and localization of critical sites in maxillary central incisors restored by means of alumina porcelain veneers under functional loading.
  
  
  METHODS
  A 3D-FEM model of a maxillary central incisor is presented. An arbitrary chewing static force of 10 N was applied with an angulation of 60 and 125 degrees to the tooth longitudinal axis at the palatal surface of the crown. The model was considered to be restored by means of alumina porcelain veneers with different tooth preparation designs. The differences in occlusal load transfer ability of the two restorative systems are discussed.
  
  
  RESULTS
  The maximum Von Mises equivalent stress values were observed in the window restorative system for both 125 and 60 degrees load angulations. When the chamfer with palatal overlap preparation was simulated, the stress distributed uniformly in the cement layer, whereas in the window preparation the stress mainly occurred in the incisal area of the cement layer.
  
  
  CONCLUSIONS
  When restoring a tooth by means of porcelain veneers, the chamfer with palatal overlap preparation better restores the natural stress distribution under load than the window technique.
authors.affiliation: Dipartimento di Scienze Odontostomatologiche e Maxillo-Facciali, Università degli Studi di Napoli Federico II, Italy.
authors.forename: Fernando
authors.initials: F
authors.lastname: Zarone
authors.forename: Davide
authors.initials: D
authors.lastname: Apicella
authors.forename: Roberto
authors.initials: R
authors.lastname: Sorrentino
authors.forename: Valeria
authors.initials: V
authors.lastname: Ferro
authors.forename: Raffaella
authors.initials: R
authors.lastname: Aversa
authors.forename: Antonio
authors.initials: A
authors.lastname: Apicella
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D001696:Biomechanical Phenomena; D001732:Bite Force; D003198:Computer Simulation; D003738:Dental Cements / Q000737:chemistry; D003776:Dental Porcelain / Q000737:chemistry*; D017267:Dental Prosthesis Design; D003801:Dental Veneers; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional; D007180:Incisor / Q000502:physiology*; D008437:Maxilla; D008954:Models, Biological; D013314:Stress, Mechanical; D013499:Surface Properties; D019246:Tooth Preparation / Q000379:methods*
chemical_list: D003738:Dental Cements; D003776:Dental Porcelain; D000537:Aluminum Oxide