The purpose of this study was to evaluate the effect of metal coping design with silicoating on the fracutre strength of resin veneered crown by grouping; group A, the position of resin-metal junction was 2㎜ buccal to the central groove, group B, the position of resin-metal junction was 2㎜ lingual to the central groove, group C, the position of resin-metal junction was 2㎜ superior to the lingual finishing margin. The fracture strength of resin veneered crown was measured with an Instron universal testing machine at buccal cusp tip and central groove. The fracture surface of the resin veneered crown was examined under the scanning electron microscope. The obtained results were as follows:
1. Loading at the buccal cusp tip, the highest fracture strength(134.0kgf) revealed in group A, and the lowest fracture strength (115.6kgf) revealed in the group B.
2. Loading at the central groove, fracture strength of group B (160.9kgf) was higher than that of group C (133.9kgf).
3. In all the cases except group A, the fracture strength loading at the central groove was higher than that at the buccal cusp tip.
4. It was revealed that the fracture occured between metal coping and opaque layer in many specimens and scanning electron micrographs showed the very compact link in the junction between metal coping and opaque layer.
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