Castability comparison of two Ni-Cr and Ni-Cr-Be Alloys in reproducing different lengths of bevel finish line

Castability of Ni-Cr alloy as an alternative to gold, has an important role in the success of metal – ceramic restorations. This research evaluates the importance of adding Berilium (Be) to Ni – Cr alloy to compare the castability of two Ni – Cr and Ni – Cr – Be alloys in reproducing different lengths of bevel finish line. Methods & Materials: Using Replica method, 30 wax-up with three different lengths of bevel were casted with Rexillium III and Wiron 99. After completing the necessary procedures, the bevel lengths were evaluated, and compared by t - test. There was no significant difference between the castability of these two alloys. The best castabilty in both alloys was seen in the range of 0.5 mm. It seems that Be is not necessary for a good castability. Although an increase in volume/surface of wax- ups in a significant range can improve the castability, the farther the margin of restoration located to the sprue, the more the possibility of incomplete castings. It seems the best castablity occurs in bevels of 0.5 mm.