Triple-blind randomized controlled trial with two parallel arms conducted between 2012 and 2014. Children 2-3 years old, from 28 rural public preschools, located in low socioeconomic areas of Chile were invited to participate. Oral health education component was given to children, parents and educators, twice yearly. A new toothbrush and toothpaste for each child was delivered to the parents at baseline and in each of the follow-up visits. The experimental group was treated with fluoride varnish every six months while the control group received placebo applications. 277 preschoolers (2 to 3 years) Main outcome: Number of Caries Incident Cases, increment dmft index

Triple-blind randomized controlled trial with two parallel arms conducted between 2012 and 2014. Children 2-3 years old, from 28 rural public preschools, located in low socioeconomic areas of Chile were invited to participate. Oral health education component was given to children, parents and educators, twice yearly. A new toothbrush and toothpaste for each child was delivered to the parents at baseline and in each of the follow-up visits. The experimental group was treated with fluoride varnish every six months while the control group received placebo applications. A trained, calibrated dentists blinded to treatment arm performed a visual-tactile dental assessment at 6, 12, 18 and 24 months. The number of incidents children with caries were recollected as the number of caries during the follow-up visits.

Nº of participant/ centres: 277 preschoolers (2 to 3 years) of 28 public preschools in non-fluoridated areas.

Main outcome: Number of Caries Incident Cases, increment dmft index

Inclusion Criteria:

• Children between 24 an 47 months, free of caries, preschooler of a public centre and living in a non-fluoridated community.

Exclusion Criteria:

• Children compromised medically, or with developmental or learning disabilities, or with a temporary residence or with dental developmental anomalies.