Clinical Assessement of Glazed Versus Polished Lithium Disilicate Crowns in Surface Roughness and Enamel Antagonists Wear

Inclusion Criteria: * Patients from 18-50 years old who are able to read and sign the informed consent document. * Physically and psychologically able to tolerate conventional restorative procedures. * Have no active periodontal or pulpal diseases, have teeth with good restorations. * Patients have no temporomandibular disorders. * Each participant needed a crown on either a first or second premolar or first or second molar in any arch. * Teeth selected shoud include: restorability with a crown:root ratio of at least 1:1. presence of an opposing natural tooth which was non-restored or minimally restored. the presence of two non-restored or minimally restored teeth opposing each other on the same quadrants as the crowned tooth and the opposing to serve as enamel controls. Minimally restored was defined as teeth which have no restoration greater than a Class II amalgam restoration. \- Willing to return for follow-up examinations and evaluation. Exclusion criteria * Patients in the growth stage with partially erupted teeth. * Patients with poor oral hygiene and motivation. * Pregnant women. * Psychiatric problems or unrealistic expectations. * Lack of opposite occluding dentition in the area intended for restoration. * Patients with temporomandibular disorders.