Increment of dental caries among Finnish dental students during a period of 2 years.

The purpose of the study was to estimate the increment of dental caries among dental students in Helsinki, who acquired good knowledge of caries prevention during their studies. The group (59 students) was examined twice with an interval of 20.2 +/- 4.1 months. Clinical findings, augmented with bitewing radiographs and an orthopantomogram, were recorded separately for each tooth surface, and individual DMFS and DS index scores were computed. In addition, the students were interviewed with regard to oral hygiene, topical fluoride application, and dietary habits. The mean DMFS and DS index scores at the first examination were 45.0 and 9.1, respectively. At the second examination, DMFS was 46.4 and the number of new decayed surfaces per student 0.54/year. Both the latter values indicated that caries progression was slow. The increment of dental caries among the dental students was much smaller than that observed earlier among other groups of university students in Finland. Further evidence that caries progression among the dental students was slow was provided by the finding that of the 318 incipient caries lesions recorded at the first examination, no more than 11 had developed into clinical caries by 20 months.