Comparisons between children who were lost in the follow-up and those who remained in the trial regarding caries risk
factors were also performed using chi-square and t-tests for independent samples. A two-tailed p-value of less than 0.05 was considered statistically significant. All statistical analyses were performed by SPSS, version 13.0. This study is registered with
ClinicalTrials.gov, number NCT00629629.