Multifunctional uses of a novel ceramic-lithium disilicate.

Objective: To familiarize the reader with the material characteristics of and indications for lithium disilicate ceramic. Summary: This paper is part of the Journal's "Masters of Esthetic Dentistry" feature. Lithium disilicate is a glass ceramic material that can be used to form restorations using either a lost-wax hot pressing technique or CAD/CAM milling procedures. Although the pressable and milled forms of the material are manufactured differently, both contain approximately 70% lithium disilicate crystals embedded in a glassy matrix. Clinical trials of lithium disilicate restorations have been in progress for 4 years, with the restorations either adhesively bonded or conventionally cemented. In addition, research at New York University, using a mechanical mouth simulator, has found that lithium disilicate crowns are strong and durable. Based on those results, little fracture or chipping would be expected clinically. In vitro wear rates are similar to those of human enamel. The pressable lithium disilicate has a variety of clinical indications, including inlays, onlays, thin veneers, crowns, and small bridges. The veneers can be pressed as thin as 0.3 mm. The milled form of the material can be used for similar indications, except for the ultra-thin veneers and bridges. Posterior crowns fabricated to full contour ("monolithic") using CAD/CAM are very strong. The paper illustrates the use of lithium disilicate in 4 clinical cases—thin veneers, three-quarter veneers, full-mouth rehabilitation with crowns, and inlays. Each case is illustrated with a series of clinical photos.