OBJECTIVE

To assess the effectiveness of motivational interviewing in preventing early childhood caries compared with conventional oral health education.

STUDY DESIGN

Twelve health care units in southern Brazil were randomly allocated in 2 groups of 6 and professionals in 1 group were trained in motivational interviewing. The mothers/children and external examiners were blinded to the intervention. The data were collected by calibrated examiners using questionnaires and a clinical examination based on modified International Caries Detection and Assessment System criteria. Of the 674 children born in the catchment area in the year 2013, 469 received the intervention (224 in the conventional oral health education group, 245 in the motivational interviewing group), and 320 were examined by the end of the study (145 in the conventional oral health education group, 175 in the motivational interviewing group), with mean age of 30 months. The final follow-up was 68%, after 3 years.

RESULTS

Mean of decayed, missing, and filled surfaces at the end of the study period for the whole sample was 1.34 (95% CI 0.97-1.71). The caries rate per 100 surface-year in the conventional oral health education group was 1.74 (95% CI 1.14-2.34) and in the motivational interviewing group, it was 0.92 (95% CI 0.63-1.20). To correct for clustering effect and unbalanced factors, multilevel Poisson regression was fitted and the effect of motivational interviewing on the incidence rate ratio was 0.40 (95% CI 0.21-0.79).

CONCLUSIONS

An intervention based on the principles of motivational interviewing style was more effective in reducing the number of surfaces affected by early childhood caries compared with conventional oral health education intervention.

TRIAL REGISTRATION

ClinicalTrials.govNCT02578966, Brazilian Registry of Clinical Trials RBR-8fvwxq.