Evaluation of preventive programs in high caries active preschool children.

Although caries prevalence in preschool children has dramatically decreased during the last decades it is still a large problem for a minor group of these children. Great efforts have been invested in finding effective preventive programs for the high caries active preschool children. However, few studies have evaluated and discussed which approach will give the best effect. The aim of the present study was to compare the effect of a "standard" preventive program with a series of programs with more extensive measures during a two-year period. At start one hundred and sixty high caries active preschool children (mean age 4 years) were included in the study. The children were randomly distributed to four groups. All groups were exposed to the basic program composed of dietary counselling, oral hygiene instructions and fluoride varnish application. Three groups were exposed to one additional preventive measure e.g. 1% chlorhexidine gel in trays, 0.2% NaF gel in trays or daily tooth brushing with 1% chlorhexidine gel. The programs were repeated seven times during the two-year study period and were executed by trained dental hygienists. Caries examination and saliva sampling for Streptococcus mutans measurements were performed at start of the study and after two years. The mean defs at start was between 10.8 and 12.6 for the four groups (NS). After two years the caries increment was 1.9 ds in the basic preventive group and between 1.9 and 2.6 (NS) in the other groups. Numerically there were more children in the chlorhexidine groups that showed reduction of Streptococcus mutans counts compared to the other groups, but the differences were small. The mean caries increment of about 1.9 ds per year in all groups indicate that all programs were effective taken into account that the children had about 11 defs at start. There were no differences in caries increment between the basic preventive group and the other groups. The conclusion was that addition of preventive measures on top of an effective basic program is a waste of resources. The effect on oral health of individual reinstruction and motivation, by a dental hygienist, seven times during the two-year study period should not be underestimated.