evaluation of wear behavior and patient satisfaction of monolithic zirconia and zirconia reinforced glass crowns after follow-up periods 0,3,6,12 months.

two groups of patients will be selected according to special inclusion criteria n=13 in each group total of 26. each group will receive one of the crowns used in this study either ( monolithic zirconia or zirconia reinforced lithium silicate glass) after crown delivery wear and patient satisfaction will be recorded at 0,3,6,12 moths follow-up periods.

Inclusion Criteria:

1. Patient age range from 20-60 to be able to read and write in order to sign the informed consent document.
2. Patients physically and psychologically able to tolerate conventional restorative procedures.
3. Patients with no active periodontal and or pulpal diseases, having teeth with good restorations.
4. Patients with root canal treated teeth requiring full coverage restorations.
5. Patients indicated for full coverage (e.g. moderate to severe discoloration, coronal fracture, malposed or malformed teeth).
6. Patients willing to return for follow-up examinations and assessments

Exclusion Criteria:

1. Patients in the growth stage with partially erupted teeth.
2. Patient with poor oral hygiene.
3. Patients with psychiatric problems or unrealistic expectations
4. Patient with no opposite occluding dentition in the area intended for restoration.
5. Patient suffering from Para functional habits.

conditions and factors which increase degree and progression of wear and clinical behavior of monolithic zirconia and zirconia reinforced lithium silicate restorations.

double blind