The present study will be performed to evaluate application of artificial intelligence in the prediction of clinical performance, marginal fit and fracture resistance of vertical "feather-edge" versus horizontal "shoulder" margin designs fabricated with two ceramic materials (zirconia and hybrid ceramic)

The objective of the present study is to characterize two different margin designs (vertical "feather-edge" and horizontal "shoulder") with two different ceramic materials (zirconia and hybrid ceramic) in terms of clinical performance, marginal fit and fracture resistance.

Primary outcome:

Predicting the follow up results using the new (artificial intelligence "AI") model for vertical "feather-edge" versus horizontal "shoulder" margin designs fabricated with two ceramic materials (zirconia and hybrid ceramic) that saves the clinical evaluation period, hence saves the expenses of the dental clinic.

Secondary outcome:

Evaluating the clinical performance, marginal fit and fracture resistance of vertical "feather-edge" versus horizontal "shoulder" margin designs fabricated with two ceramic materials (zirconia and hybrid ceramic).

Inclusion Criteria:

• 1. Age range of patients should be 20-50 years old, able to read and sign the informed consent document. 2. Patient with posterior molars indicated for full coverage restorations. 3. Patient should be able to physically and psychologically tolerate conventional restorative procedures. 4. Patients who are willing to return for follow-up examination and evaluation. 5. Indicated molar should have adequate tooth preparation length to ensure proper retention and resistance form. 6. Patient with sound contralateral or adjacent tooth to the selected tooth requiring full coverage restoration.

Exclusion Criteria:

1. Patient in the growth stage with partially erupted teeth.
2. Patient with poor oral hygiene and motivation.
3. Pregnant women.
4. Patient with psychiatric problems or unrealistic expectations.
5. Patients with no opposing occluding dentition in the area intended for restoration.
6. Patients with parafunctional habits. -