The side to which interventions or control is assigned to will be recorded and all records of all patients will be kept with the main supervisor. Blinding of the operator is not possible, because the color of intervention and control solution is different. The operator is blinded until randomization into groups, to avoid biases with regard to the application of antibacterial agent. Also, the examiner who will carry the microbiological analysis of dentin samples will be blinded to the type of agent applied during treatment. Finally, the treatment results will be assessed blindly by a statistician.