Subjective Health Behaviours Improve Oral Health in Grade IV Children

Objectives: The purpose of this study was to determine the effects of health behaviours and lifestyles on the oral health in children.

Methods: The subjects were 228 Grade III and 211 Grade IV students in Okinawa island. DMF, df, OHI-S and PMA were examined. Kappa values within the 4 examiners were more than 0.7 for each indicator. The subjects and the mentors were surveyed by questionnaires to determine the subjects' lifestyle and health behaviours.

Results: DMFT, dft, PMA and OHI-S in Grade III were 3.97±2.77, 0.77±1.10, 8.95±7.30, and 1.71±0.68, respectively, and also 3.67±2.76, 1.30±1.38, 9.46±7.42, 1.63±0.70 in Grade IV. The logistic regression model in Grade III showed that there was no significant relationship between PMA and questions, whereas the number of untreated dental caries is negatively correlate to three times of tooth brushings per day (p<0.01). Also there were significant relationships between OHI-S and some lifestyles such as "Never skip breakfast" or "Enough sleeping time" as well as the numbers of tooth brushing per day (p<0.01, respectively). In Grade IV, however, there was a significant relationship between PMA and a question regarding regular checkup (p<0.01). The students, who receive a dental checkup besides the check up by a school dentist, showed lower PMA than others. Furthermore, the factors resulting in the reduction of the number of untreated dental caries have been interestingly changed to more subjective and independent health behaviours, which were examined by the following questions; "Promoting my own health by myself.", "Visiting a dentist quickly, if decay is found." etc (p<0.01, respectively)

Conclusion: In Grade III students, oral health was improved by the behaviours learned objectively during the regular life; however, the conditions of Grade IV were improved by their subjective behaviours. Health education leading the subjective behaviours would be required for these grades.