the aim of present study is to evaluate clinically the fracture liability , marginal adaptation , and patient satisfaction of conservative versus conventional ceramic Onlays use e-max press to restore defective restored molar with old restoration or caries. with one or more cusp defect

Inclusion Criteria:Inclusion criteria:

All subjects are required to be:

1-From 18-50 years old, be able to read and sign the informed consent document. 2- Have no active periodontal or pulpal diseases, have teeth with good restorations 3- Psychologically and physically able to withstand conventional dental procedures 4- Patients with teeth problems indicated for onlay restoration:

1. Decayed teeth

2. Teeth restored with defected filling restorations

3. Teeth with occlusal defect 5- Able to return for follow-up examinations and evaluation Exclusion criteria

   1. Patient less than 18 or more than 50 years

   2. Patient with active resistant periodontal diseases

   3. Patients with poor oral hygiene and uncooperative patients

   4. Pregnant women

   5. Patients in the growth stage with partially erupted teeth

   6. Psychiatric problems or unrealistic expectations

   7. Lack of opposing dentition in the area of interest

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