A randomized controlled trial of 6-month dental home visits on 24-month caries incidence in preschool children

OBJECTIVES: This paper reports on the effect of 6-month dental home visits compared to no dental home visits on 24-month caries incidence in 5- to 6-year-olds.

METHODS: 5- to 6-year-olds attending kindergartens were randomized to receive either 6-month dental home visits and education leaflets (Intervention group) or education leaflets alone (Control group) over 24 months. To detect a 15% difference in caries incidence with a significance level of 5% and power of 80%, 88 children were calculated to be needed in the Intervention group and 88 in the Control. Baseline clinical data included oral examinations at the kindergartens. Follow-up visits were made on the 6th, 12th and 18th month. At the end of the 24 months, both the Intervention and Control groups were visited for oral examinations. The primary outcome was caries incidence, measured by the number and proportion of children who developed new caries in the primary molars after 24 months. The secondary outcome was the number of primary molars that developed new caries (d-pms). Frequency distributions of participants by baseline socio-demographic characteristics and caries experience were calculated. The chi-square test was used to test differences between the caries experience in the Intervention and Control groups. The t test was used to compare the mean number of primary molars developing new caries between the Intervention Group and the Control Group. The number of children needed to treat (NNT) was also calculated.

RESULTS: At the 24-month follow-up, 19 (14.4%) developed new caries in the Intervention Group, compared to 60 (60.0%) in the Control Group (p = .001). On average, 0.2 (95% CI = 0.1-0.3) tooth per child in the Intervention Group was observed to have developed new caries compared to 1.1 (95% CI = 0.8-1.3) tooth per child in the Control Group (p = .001). The number of children needed to treat (NNT) to prevent one child from developing new caries was 2.2.

CONCLUSIONS: The present study has demonstrated that 6-month home visits to families of 5- to 6-year-olds are effective in caries prevention in 5- to 6-year-olds of low-income families in a middle-income country where access to health services, including oral health promotion services, is limited.