This prospective cohort study in children will determine if: topical povidone iodine 10% followed by topical fluoride varnish is superior to placebo iodine followed two different varnishes alone to prevent tooth decay (dental caries).

Primary Objectives:

1. To determine if sequential topical application of Povidone Iodine (Povi-One, 10% PVP-I) followed by the Fluoride Varnish (Fluorimax, 2.5% NaF) every 3 months is superior to an active control (placebo + standard of care FV (Fluorimax) at 24 months post baseline. Specifically, prevention of caries lesions in primary teeth that either are sound, have only d1 (white spots) lesions or unerupted at baseline.
2. To determine if the sequential topical application of Povidone Iodine (Povi-One, 10% PVP-I) followed by the Fluoride Varnish (Fluorimax, 2.5% NaF) every 3 months is superior to active control (placebo + ClinPro Clear Fluoride Treatment (Solventum, 2.1% NaF) at 24 months post baseline. Specifically, prevention of caries lesions in primary teeth that either are sound, have only d1 (white spots) lesions or unerupted at baseline.

Secondary Objective:

To determine if sequential topical application of placebo followed by the Fluoride Varnish (Fluorimax, 2.5% NaF) every 3 months is superior to placebo followed by Clinpro Clear Fluoride Treatment (Solventum, 2.1% NaF) at 24 months post baseline.

Study Design: Open label prospective cohort study. The study will be conducted in two hospitals in Puno serving the "Control de Crecimiento y Desarrollo (CRED)" program, conducted under the Ministry of Health. The treatment at each site will be the same with different treatments on different days of the week chosen randomly, stratified by hospital. There will be no individual randomization.

Participants: Children 6-24 months of age at enrollment. To be eligible a child will have at least 1 erupted tooth that is either sound or has only a d1 (white spot) lesion. Children will be excluded under the following conditions:

1. Previous treatment with fluoride varnish
2. Known allergy to iodine
3. Diagnosis of thyroid disease
4. Chronic, prophylactic use of antibiotics
5. Treatment with another investigational drug or other intervention within 30 days preceding the Baseline Visit.
6. Visible cavities (d2-4) in the erupted primary teeth
7. Presence of intraoral soft tissue pathology (gum boil)
8. Parent anticipates the child will move from current city during the next 24 months.

Products Being Studied:

The 10% PVP-I (Povi-One) and 2.5% FV (Fluorimax) will be obtained from Elevate Oral Care, LLC., West Palm Beach, FL USA. The ClinPro Clear (2.1% NaF) will be purchased in the marketplace by Elevate and made available to the study.

Inclusion Criteria:

• Children 6-24 months of age at enrollment. To be eligible a child will have at least 1 erupted tooth that is either sound or has only a d1 (white spot) lesion.

Exclusion Criteria:

1. Previous treatment with fluoride varnish
2. Known allergy to iodine
3. Diagnosis of thyroid disease
4. Chronic, prophylactic use of antibiotics
5. Treatment with another investigational drug or other intervention within 30 days preceding the Baseline Visit.
6. Visible cavities (d2-4) in the erupted primary teeth
7. Presence of intraoral soft tissue pathology (gum boil)
8. Parent anticipates the child will move from current city during the next 24 months.

Children served by two health centers in Puno serving the "Control de Crecimiento y Desarrollo (CRED)" program and the Faculty of Health Sciences, Professional School of Dentistry, National University of the Altiplano, Puno, Peru.

Deidentified participant level data will be made available upon request