title: Influence of connector design and material composition and veneering on the stress distribution of all-ceramic fixed dental prostheses: a finite element study.
abstract: OBJECTIVE
  Finite element analysis is a standard method to simulate the stress distribution in all-ceramic dental restorations in order to estimate the loading capacity of the brittle components. The hypothesis of this study was that stresses in the connector area of a veneered FDP are strongly influenced by the framework dimensions and the veneering material.
  
  
  METHODS
  Finite element analyzes of bilayered fixed dental prostheses with three different framework-designs and three different veneering materials were conducted, applying the loads onto the veneering as well as directly onto the framework. The outer shape of the veneering ceramic remained constant for all cases.
  
  
  RESULTS
  The maximum first principal stresses in the framework of the fixed dental prostheses (FDP) decreased with smaller framework dimensions when the load was applied on the veneering. By applying the load directly onto the framework of the FDP without veneering a converse tendency was found. The variation of the veneering material lead to the conclusion that stresses in the framework became higher with decreasing Young's modulus of the veneer, while the stresses in the veneer increased at the same time.
  
  
  CONCLUSIONS
  The veneering material plays a significant role for the failure of a FDP and cannot be neglected neither in testing nor in simulation. Thus the loading capacity of dental restorations can only be reasonably evaluated when the whole restoration is taken into account, including framework and veneering.
authors: Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Pauwelsstrasse 30, 52074 Aachen, Germany.
authors: Kristina
authors: K
authors: Möllers
authors: Wiebke
authors: W
authors: Pätzold
authors: Daniel
authors: D
authors: Parkot
authors: Armin
authors: A
authors: Kirsten
authors: Jan-Frederik
authors: JF
authors: Güth
authors: Daniel
authors: D
authors: Edelhoff
authors: Horst
authors: H
authors: Fischer