A single-blinded randomized clinical trial with a split-mouth design that will assess the 12-month clinical and radiographic success of two minimally invasive treatment techniques, one using a chemo-mechanical caries removal agent and one using a caries arresting agent, for the treatment of deep caries in primary molars.

Fifty children (100 teeth) aged 4 to 8 years with a non-contributary medical history and at least two carious primary molars (ICDAS 5 and 6) on different quadrants will be randomly assigned to either treatment group, using computer-generated numbers.

Each cavitated lesion will be isolated with cotton rolls and air-dried before being treated with one of the two types of minimal intervention technique according to the manufacturer's instructions. After the application of the agents all teeth will be restored using a high viscosity glass ionomer cement.

Patients will be followed clinically at 6 and 12 months and radiographically at 12 months to evaluate success of the procedures.

Inclusion Criteria:

• Children aged 4 to 8 years with a non-contributary medical history and sufficient compliance for the caries treatment will be included. The eligible children should have at least two carious primary molars (cavitated lesions up to 2/3 of dentin, corresponding to ICDAS 5 and 6) on different quadrants without any periapical pathology detected radiographically.

Exclusion Criteria:

• Children aged below 4 years and above 8 years, with compromised medical history and/or allergies, with clinical or radiographic signs or symptoms of pulp pathology and with developmental dental defects will be excluded.