Lithium Disilicate Crowns Study

Inclusion Criteria: * Patients will be at least 18 years of age, of either gender, and of any ethnic background. * Each patient should have at least one carious lesion or defective restoration to be restored on a maxillary or mandibular premolar or molar tooth. * Each lesion or defective restoration should exhibit sufficient size or loss of tooth structure requiring a full crown restoration. * The tooth should have at least one opposing tooth in occlusion and one adjacent tooth with an intact proximal contact. * All teeth will test vital and be asymptomatic at the beginning of treatment. No more than two restorations will be placed per patient. Exclusion Criteria: * Devital or sensitive teeth * Teeth with prior endodontic treatment of any kind * Teeth with a history of direct or indirect pulp capping procedures * Patients with significant untreated dental disease to include periodontitis and/or rampant caries * Women who self-report that they are possibly pregnant, pregnant, or lactating, as elective dental treatment is not indicated at these times * Patients with a self-reported past history of allergies to the materials to be used in the study including composite resin cements or ceramic restorative materials * Patients unable to return for the recall appointments