الفهرس 
Introduction
Marginal fit of galvanoceramic crownsOnly 14 pages are availabe for public view
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Abstract
Electroforming technology is used to form substructures for porcelain inlays and crowns. This technique may be used as an alternative to the currently available porcelainfusedtometal and allceramic systems. Materials And Methods: This invitro study was planned to evaluate the marginal fit of galvanoceramic crowns before and after porcelain application and after cementation using three different luting cements. Also this study evaluated both microleakage and internal adaptation of galvanoceramic crowns after cementation with three different luting cements. 30 specimens were used and divided into three main groups 10 specimens each according to the type of luting cements used. The first group was cemented with zinc phosphate cement. The second group was cemented with glass ionomer cement and the third group was cemented with adhesive resin cement. The marginal fit was evaluated before and after porcelain application and after cementation. The surfaces of the restored teeth, expect for 1mm around the veneer margins, were coated with varnish before being submerged in a solution of 50% silver nitrate. Each cemented crown was embedded in resin and sectioned mesiodistally with a diamond disc. The linear penetration of silver nitrate stains from the external margin of the cement at both tooth/cement and crown cement interface was measured. Results: Mean marginal fit discrepancies of galvanoceramic crowns were not affected by porcelain application. Mean marginal fit discrepancies were significantly higher after cementation. The crowns cemented with adhesive cement showed the best marginal adaptation followed by that cemented with glass ionomer cement while zinc phosphate cement showed the least adaptation. Galvanoceramic crowns cemented with adhesive resin cement showed less leakage values at either tooth/cement and crown/cement interfaces as compared to that cemented with either zinc phosphate or glass ionomer cement that showed the least leakage values.