Abstract
BACKGROUND: Early childhood caries (ECC) affects children across Japan and throughout the world. Thus, it is important to identify dietary and dental care habits that either promote oral health or cause ECC. The objective of this study was to identify protective and risk factors associated with ECC in Japan. METHODS: In a typical rural Japanese community, we selected children born between 2004 and 2008 who had received checkups at their community health center including oral examinations conducted by dentists. We obtained data from children's records and from a questionnaire filled out by parents. We enrolled only children who at their checkup for 18-month-olds had no caries, and we obtained data about them at their checkup for 3-year-olds. We classified children as either having caries (treated or untreated) or being caries-free. We conducted bivariate analyses using data on child/family demographic characteristics, child's dietary habits, and child/parental oral health habits. We also conducted logistic regression analysis to control for variables and identify predictors of the presence/absence of caries. RESULTS: Five hundred sixty six children (278 boys, 288 girls) were enrolled and followed. After 2 years, 173 children (30.6%) presented with caries. Logistic regression analysis predicting caries at follow-up identified the interaction term "bottlefed overnight and brushed irregularly" at 18 months of age as a highly significant predictor of developing caries-adjusted odds ratio (AOR) of 14.27, 95% confidence interval (CI) 1.02-199.71. Two variables measured at follow-up were also significant predictors: having low levels of dental plaque (AOR 2.41, 95% CI 1.34-4.35) and having a mother who had untreated caries (AOR 1.84, 95% CI 1.09-3.12). CONCLUSION: Public health efforts should encourage parents to eliminate bottle feeding overnight and promote brushing twice daily as children's teeth begin to erupt. Greater efforts should be made to teach parents and daytime caregivers how to brush effectively to remove all plaque. Health professionals should pay close attention to mothers' oral health status. Mothers with caries should receive prompt treatment and be assisted in developing better dietary and oral health habits that will benefit themselves and their children. Policies and programs should focus more on family oral health rather than just child oral health.