The purpose of this study was to compare difference in the stress distributions of crown according to dental cements under static load. To evaluate the stresses of crown, dental cement, abutment tooth, a mandibular first molar was used and prepared to same dimension.
According to the FEM modelling method, the casting gold crown was designed. The teeth and the casting gold restorations were divided into three groups and modelled on computer as natural condition, 12㎏ of static force was loaded individually each two point of crown; buccal cusp tip, central fossa. The Von Mises stresses developed in the casting gold restoration according to dental cements. The Von Mises stress as were measured at buccal and lingual slope between crown and cement and abutment. The form of crown was designed ; thickness of functional cusp - 1.5㎜, central fossa - 1.0㎜. A two dimensional stress analysis model was constructed to represent a mandibular first molar. Finite element models were created and analysed using software SUPER SAP for IBM AT 386 personal computer.
The results obtained were as follows ;
1. On loading condition, there was significant difference according to dental cements.
2. There were proportional relationship between cement´s strength and stress distribution.
3. On loading condition vertically, stress was distributed more favorably in zinc phosphate cement than others.
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