the study evaluate the clinical outcome of zirconia versus lithium disilicate overlays restorations for restoring vital young permanent first molar teeth affected with moderate form of molar Incisor hypomineralization: randomized clinical trial.

To compare the one-year clinical outcome of zirconia versus lithium disilicate overlays restorations. Materials and methods: Twenty patients were distributed into two groups in relation to the material used for the fabrication of overlays restorations; group (Z) (n=10): patients received zirconia restorations, group (EC): patients received IPS E.max Cad restorations. Clinical and radiographic evaluations of these restorations were carried out at base line (1 week), 3, 6 and 12 months after cementation using FDI World Dental Federation criteria

Inclusion Criteria:

• Children's age ranging from 10 to 15 years old.
• Existence of large carious lesion in young permanent first molar teeth associated with weak cusps.
• Signs of vital pulp without symptoms of pulpitis.
• Presence of antagonists and adjacent teeth and occlusal contacts with good level of oral hygiene.
• Children should be able to physically and psychologically tolerate conventional restorative procedures.

Exclusion Criteria:

• Children with poor oral hygiene and symptoms of pulpitis.
• Children suffer from parafunctional habits.
• Children with any debilitating systemic disorder.

Twenty patients were distributed into two groups in relation to the material used for the fabrication of overlays restorations; group (Z) (n=10): patients received zirconia restorations, group (EC): patients received IPS E.max Cad restorations. Clinical and radiographic evaluations of these restorations were carried out at base line (1 week), 3, 6 and 12 months after cementation using FDI World Dental Federation criteria

one year

alaaaldehna.26@azhar.edu.eg