The research includes a clinical, longitudinal, and blind study, in which a total of 31 patients: 15 children from the province of Pichincha, Ecuador and an additional 15 from the province of Cotopaxi, Ecuador, are chosen according to inclusion and exclusion criteria upon informed consent of their parents and or legal guardian. In addition, a clinical examination, a basic medical history, and a diagnosis according to TF and Dean's index are the parameters for patient eligibility for this study. It is important to note that the infiltrant resin technique follows the manufacturers' instructions. Finally, a three month follow up will be reinforced in order to clinically evaluate the treated teeth at the end of one year.