Influence Of CAD & 3-D Printing Technology in Die-Spacer thickness

Venting, axial grooves and provision of axial cement space are methods that have been used to create space between the intaglio surface of crowns and the tooth preparation. The application of paint-on die spacer prior to waxing is the most popular method for providing this space.The use of die spacer can reduce the hydraulic pressure between the cement and restoration; hence it allows better seating of a cast restoration, decreases seating time and allows excess cement to escape.In addition, die spacer has been shown to improve the marginal fit between the restoration and tooth preparation, decreasing the risk of cement dissolution, plaque accumulation, recurrent decay, and periodontal problems.Holmes et al defined the internal gap as the perpendicular measurement from the internal surface of the casting to the axial wall of the preparation; the same measurement at the margin was referred to as the marginal gap.According to Tuntiprawon and Wilson, all ceramic crowns displayed a greater fracture strength when the mean internal gap at the axial wall was < 73 um.