Abstract
Aims: The aim of This study was to compare the marginal and internal adaptation of cores which arefabricated of different materials and systems. Methods: In this experimental study, one Ivorinemaxillary right first premolar (A -3 Z; Frasaco, Tettnang, Germany) was prepared for full coverage ofzirconium,Nickle chromium and ceramic cores. The tooth was prepared with 1 mm rounded shoulderand 2-5 degrees tapering. Nickle chromium die was prepared for full coverage of upper first premolar,and duplicated to produce fifteen resin stone dies.The specimens were devided in to three groups (n=5).Cores were fabricated using NiCr, Empress ceramic, manual Zirconia frame works respectively.Internal space replica technique was used to evaluate the marginal and internal adaptation of the coresusing Fit and Bite checker silicone material. The resulted replica of each core was sectioned and thethickness of the black and white silicone layer was measured at marginal and internal points.Data wascalculated and compared statistically using Kruskal_Wallis test at p<0.05. Results: There was asignificant difference in the internal adaptation of different core materials . Copings fabricated ofzirconia material have shown minimum thickness and higher internal adaptability. Conclusions:Zirconia copings have superior marginal adaptability when compared to NiCr and Empress Cerammaterials.
