Randomized controlled trial of caries preventive programs for pre-school children

Objectives: To explore the effects of removing mutans streptococci form oral cavity by three years follow up study. Methods: Salivary levels of oral bacteria were evaluated three times: medical check-ups, after the dental caries treatment, after professional preventive care. 157 children with high levels of mutans streptococci were selected at the pre-school medical check-ups. The children were randomly allocated into three groups: professional preventive care with PMTC and fluoride varnish by custom made tray with (Group A) and with povidone iodine (Group B), no intervention (Group C). The intervention was carried out only once, then recommended the home care with fluoride (Group A) or povidone iodine (Group B) by custom made tray for one month. The oral examinations were carried out at annual check-ups and the follow up periods were three years. Results: Statistically significant reduction of the mutans streptococci (log CFU) was observed after the dental caries treatment (Group A: 6.2 +/- 5.8 to 3.6 +/- 1.6 and B : 6.1+/- 5.8 to 3.6 +/- 1.5). However, the reduction of it was not statistically significant in both Group A (3.6 +/- 1.6 to 3.6 +/- 1.5 ) and B (3.6 +/- 1.5 to 3.6 +/- 1.3 ) when compared before and after the preventive programs. After three years, the difference of the incidence of the new dental caries was not statistically significant (Mean DMFT Group A : 0.53 +/- 1.02, B : 0.29 +/- 0.83and C: 0.41 +/- 0.93). Conclusion: The preventive program is effective for the short term periods however, the only once intervention is not sufficient. The continuous intervention is indispensable for the prevention of the dental caries.