Can protective factors prevent caries in preschool children?

Design A case-control randomised trial.Case/control selection Preschools in Tehran/Iran were selected for inclusion through multi-stage cluster random sampling. They were divided into strata based on population density and a preschool from each was randomly selected. From this, children aged 4-6 years were identified. Twelve children from each preschool were placed into the 'caries-free' experimental group and 12 into the 'caries present' control group. Where insufficient experimental group participants were recruited, additional control group participants were included. Incentives for participation included free preventive procedures and completion of required dental treatment. All participants underwent intraoral examinations and independent parent questionnaires. The study received ethical approval.Data analysis Participants were assessed objectively for caries status by blinded calibrated examiners, using a standardised and validated questionnaire as part of a face-to-face interview. This questionnaire included three domains: sociodemographic factors, behavioural oral health measures and feeding practices/dietary habits. Sociodemographic characteristic recorded included sex, age, the number of siblings and the parents' level of education. A logistic regression model was applied to identify caries-free protective factors (p <0.05). The collected data was then entered into the SPSS software version 21 for statistical analysis.Results In total, 528 participants were recruited, with 28 ineligible due to lack of consent. This resulted in 230 participants in the experimental group and 270 in the control group. Protective factors against dental caries were identified as: dental check-up as the cause of dental visit; being the eldest child in the family; minimised night feeding; family owning their residence; and parents having university-level education (p <0.05). Antibiotic consumption and mothers who were not able to make their children brush their teeth were not identified as factors.Conclusions The outcome showed that protective factors including regular check-up and socioeconomic factors are associated with dental health. Dental check-up as the cause of dental visit, being the eldest child in the family, minimised night feeding, family owning their residence and parents having university-level education reduce the chance of preschool children suffering dental caries.