Clini Asses of Retentn,Pt Satisfactn and Recurrent Caries of Endocrs Versus Post Crs Using Reinforced Lithium Silicate

Inclusion Criteria: * • Patient age range of 18-55 years. * Patients physically and psychologically able to tolerate conventional restorative procedures. * Co-operative patients approving to participate in this trial. * Patients with root canal treated lower first molars requiring full coverage restoration. * Patients willing to return for follow-up examinations and assessments. * Endodontically treated teeth with absence of clinical diagnosis of periapical pathosis, fistula, swelling of periodontal tissues, abnormal tooth mobility and history of sensitivity to pressure Exclusion Criteria: * Patients in the growth stage with partially erupted teeth. * Patients with poor oral hygiene. * Disabilities which will not be cooperative patient for the study. * Systemic diseases or severe medically compromised patients as uncontrolled diabetes or oral cancer. * Patients suffer from parafunctional habits * Teeth with fractured roots * Teeth with lesions extending apical to the cemento-enamel junction * Poor oral hygiene.