Variation in Caries Prevalence Related to Combinations of Dietary and Oral Hygiene Habits and Chewing Fluoride Tablets in 4-Year-Old Children

Abstract

The study covered 515 children, aged 4 years and 1 month at the time of examination, selected from a total sample of about 1,600 individuals from two limited areas in southern Sweden. The investigation involved clinical-roentgenological registration of caries, excluding subsurface lesions, and of restorations in smooth surfaces of the entire primary dentition. The selection criteria were a combination of three habit variables, as follows. Diet: (1) ≤ 6 meals per day, including ‘suitable’ snacks, (2) 5–6 or (3) > 6 consumptions a day, including at least 1 ‘unsuitable’ snack with a high-sucrose component. Oral hygiene: (1) an adult brushed the child’s teeth at least once a day, (2) the child did this him/herself at least once a day or (3) seldom or never. Chewing fluoride tablets (1–2 tablets containing 0.25 mg F per day): (1) children who had started to chew tablets before the age of 2 years, (2) children who had started between 2 and 3 years of age or (3) children who had not chewed such tablets. Furthermore, the subjects were not to have been exposed to drinking water with a fluorine content exceeding 0.5 ppm, and any chewing of fluoride tablets was not to have been discontinued before the age of 3 years and 9 months. The statistical analysis (applying Wilcoxon’s distribution-free methods) supported the following conclusions: The order of efficiency of the preventive measures was: (1) dietary restrictions, (2) oral hygiene and (3) chewing fluoride tablets. The effect of one preventive measure is greatest when the others are most unfavourable. The lower the prevalence of caries, the lower the effect of each preventive measure, the reduction being greatest for the measure with the weakest capacity. Finally, the study demonstrates the importance, when assessing the real effect of a preventive measure, of taking the levels of other habits into consideration.