Preparation Guidelines For Layered Or Monolithic Restorations

14/09/2022

For restorations within the aesthetic zone, a Zirconia crown layered on the facial or full layering will provide optimal results. Over the past few years, layering porcelain techniques have improved significantly. Hence, a Zirconia substructure that has been layered with porcelain is unlikely to chip or fracture on the occlusal or incisal.

However, suppose maximum strength is required because a patient has bruxism, a heavy bite, or where there is only limited occlusal clearance. In that case, a monolithic crown may be a better posterior solution. Thanks to newer monolithic zirconia (single, solid blocks of zirconia), this crown is nearly unbreakable and built to withstand the harsh environment the posterior of the mouth endures better than all-porcelain crowns. Vsmile ST White and Preshade Blocks Monolithic restorations provide an increasingly aesthetic result.

· There should be a 1.0 to 1.5 mm occlusal depth cut for a full-contour monolithic Zirconia crown to achieve appropriate occlusal anatomy.

· You will need to ensure a 1.0 to 1.5 mm functional cusp tip reduction, a 0.5 mm gingival chamfer reduction, a 6 to 8-degree taper to the axial walls, and a 1.0 mm occlusal 1/3 reduction of the functional cusp.

· Prepare a 0.3 to 0.5 mm chamfer for the marginal design to allow for a more accurate mill of the pre-sintered zirconia.