The aim of study is to evaluate the clinical performance of posterior restorations using HEMA free universal adhesive versus HEMA containing universal adhesive over one year using USPHS criteria.

The study is intended to evaluate the HEMA free universal adhesive versus HEMA containing universal adhesive when both used in conjunction with giomer aesthetic restorations in occlusal cavities in posterior teeth ICDAS III and IV.

The restorations will be evaluated at baseline, 6 and 12 months according to modified USPHS criteria in terms of marginal staining, marginal adaptation and caries recurrence.

Patients will be recruited from outpatient clinic of conservative dentistry department, cairo university according to inclusion and exclusion criteria. patient will be randomly allocated to intervention or control group.

Inclusion Criteria of participants:

• Patients with occlusal caries in molars classified as ICDAS III or IV.
• 19-35 years.
• Males or Females.
• Co-operative patients approving to participate in the trial.

Exclusion criteria of participants:

• Pregnancy.
• Disabilities.
• Systemic disease or severe medical complications.
• Allergic history concerning methacrylate.
• Rampant caries.
• Heavy smoking.
• Xerostomia.
• Lack of compliance.
• Evidence of severe bruxism, clenching, or tempromandibular joint disorders.