Teeth selected for intervention with Atraumatic Restorative Treatment will receive Glass Ionomer restorations (control) or MI varnish (test) before receiving the Glass Ionomer restoration

Patients selected to participate in the study will be randomly assigned into 2 groups.

Group 1 (test): who will receive casein Phosphopeptide Amorphous Calcium Phosphate (CPP-ACP) + ART in the teeth selected, excavating only the caries infected dentine and preserving the caries affected dentine.

Group 2 (control): Who will receive ART only in the teeth selected, excavating only the caries infected dentine and preserving the caries affected dentine.

Inclusion Criteria:

1. Healthy patients.

2. Patients with an age range of 6-8 years old for clinical evaluation.

3. Patients ranking definitely positive or positive on Frankl scale.

4. Patients having at least 1 symptomless primary molar with caries extending to the dentine (International Caries Detection and Assessment System (ICDAS II) code 4, 5 & 6).

5. The presence of the permanent successors when examined by periapical X-ray.

6. Patients who will agree to participate in the study. For the ex-vivo sample

   1. Patients with an age range of 9-11 years old.
   2. The selected teeth should have more than half of their roots physiologically resorbed when examined by periapical X-ray.

Exclusion Criteria:

1. Patients with special health care needs (physical, mental or medical).
2. Primary molars that are mobile, ankylosed or have periapical pathology on initial examination clinically and radiographically.