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Purpose: The purpose of this study was to examine the influence of the elastic modulus of
cement and luting thickness on the resulting stresses in an axially loaded crown
cemented onto a first premolar. A comparison of these stresses was also made with the
strength of the constituent materials making up the crown. Materials and Methods:
Examination of the stresses on a restored crown was conducted using finite element
analysis. Eight different axisymmetric models containing combinations of In-Ceram or
gold coping, using adhesive resin or zinc phosphate cement as the luting agent, with
thicknesses of either 0.05 or 0.1 mm were analyzed. Results: The peak tensile principal
stresses in the porcelain remained below its material fracture strength. The same was true
for the peak stress in the adhesive resin compared to its fracture and chemical bond
strength. This was not the case for zinc phosphate. The influence of the luting agent’s
elastic modulus on the stresses in the crown was minor, and the influence of luting
thickness was even less. Conclusion: The role of the luting agent was primarily one that
effectively transferred the resulting stresses between the relatively stiff coping and
underlying dentin. There was no evidence of the luting agent itself playing a significant
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