Restoration of Extremely Dark Tetracycline-Stained Teeth with Monolithic Gradient Zirconia.

The dentist-laboratory technician restorative team has been challenged over the last 50 years to find a suitable restorative material to treat the extensive tooth staining, born out of the late 1960s and early 1970s, from the ingestion of tetracycline. For milder cases, combinations of bleaching and/or a variety of direct and indirect materials could be effective. However, truly dark teeth necessitated finding a balance between blocking out the darkened tooth structure and the ability to provide lifelike dental restorations with suitable optical metamerisms. This article discusses the properties of dental zirconia and its performance in fixed dental prostheses. A case study illustrating how monolithic, gradient zirconia can provide beautiful, lifelike restorations for even the darkest tetracycline-stained teeth is provided. [ABSTRACT FROM AUTHOR]