Introduction: Early childhood caries (ECC) is common among Hong Kong preschool children. It is a disease caused by dental plaque bacteria and may be controlled by good toothbrushing habits. However, preschool children are often too young to perform effective tothbrushing, and therefore parental toothbrushing is recommended for them. The oral hygiene status of Hong Kong preschool children is usually not good and parental toothbrushing is not common. Fluoride varnish is effective in preventing dental caries in school children and adolescents but its effectiveness in preventing dental caries in preschool children is still inconclusive. Objective: To investigate the effectiveness of hands-on training in parental toothbrushing, with or without semi-annual applications of a 5% sodium fluoride varnish in preventing ECC. Methods: Children aged 8-23 months were recruited and randomly allocated to one of three groups: Group 1 - positive control, a brief oral health education to parents; Group 2 - oral health education to parents, hands-on training in parental toothbrushing, and home visits every six months to reinforce parental toothbrushing; Group 3 - application of a 5% sodium fluoride varnish onto the child’s teeth during home visits in addition to the intervention provided to Group 2. Clinical examination of the children and a questionnaire survey of the parents were conducted at baseline. Interventions for the children and parents were delivered according to their group assignment. Evaluation of the main outcome, development of new dental caries, was conducted after 24 months through clinical examination. Information on children’s oral health-related behaviors and parents’ knowledge of and attitude towards their child’s oral health was collected using a questionnaire at the 24-month follow-up. Results: Out of the 450 children recruited at baseline, 415 (92%) children were examined after 24 months and all examined children’s parents completed the questionnaire. Including both noncavitated and cavitated carious lesions, the incidences of ECC in Gp1 to Gp3 were 11.9%, 11.8%, and 17.5%, respectively (p > 0.05) and; the mean dmfs scores in Gp1 to Gp3 were 0.3, 0.2, and 0.4, respectively (p > 0.05). Proportions of parents who practiced parental toothbrushing twice a day were 62.7%, 60.4%, and 65.7% in Gp1, Gp2, and Gp3, respectively (p > 0.05). Results from a logistic regression analysis showed that children who were older, who had poorer oral hygiene, who had high frequency of sugary snack intake, who had visited a dentist during the study, and whose parents had lower education level would have a higher chance to develop new dental caries during the 24-month study period. Conclusion: Hands-on training in parental toothbrushing, reinforced by face-to-face interview every 6 months, with or without a semi-annual application of 5% sodium fluoride varnish, may not have any additional effect on preventing development of dental caries in young children compared to the standard oral health education provided to parents in Hong Kong. The child’s socio-demographic background, oral hygiene status, and frequency of sugary snack intake are related to ECC. / published_or_final_version / Dentistry / Doctoral / Doctor of Philosophy

Includes bibliographical references (leaves 232-247). Obtained information on dental caries and fluorosis among a representative sample of Vietnamese children. Also collected information on factors likely to influence caries experience and dental fluorosis and undertook statistical analyses to examine the relationship between fluoride in drinking water, dental caries and dental fluorosis

Bibliography: leaves 268-281. / xviii, 281 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--Adelaide University, Dept. of Public Health, 2001

Our study adds to the understanding of dental caries prevention in underserved populations. Dental caries is the most common disease of childhood but can be easily prevented. It is therefore essential that policy makers use evidence to promote policies that will help reduce the burden of caries in high-risk children. We collected socioeconomic and demographic data through written surveys from parents of children at the Lyford Consolidated Independent School District in Willacy County. We got a 60% response to our survey. The survey data was matched with dental examination data from a teledentistry project. Only 19% of children in our matched sample had any sealant but 43% had at least one dental caries. Of those without sealants, almost half (49%) had caries while of those with sealants only 19% had any caries. We also found that while half (48%) of those from low-income households (ie, annual income <$25,000) had caries, only a third (34%) of those in high-income households had any caries. Our data analysis involved econometric modeling to study the impact of various factors including dental sealants on the occurrence of dental caries. We assumed dental sealant application to be a proxy for past preventive dental care. We used multivariate probit regression to test for endogeneity in our model. The estimation results from univariate probit models showed a strong and robust preventive effect of dental sealants on dental caries. We used Ordinary Least Squares (OLS), logit, probit, and logistic regressions to confirm the results and obtained similar findings. We used our fitted model to simulate the effect of providing sealants to all children in our sample and found that there will be a 52% - 68% decrease in the mean predicted probability of caries in different scenarios. Finally, we used cost estimates from published studies and the annual survey of dental fee by the American Dental Association to calculate cost-benefit of providing sealants through school-based programs. We found school-based sealant programs to be cost-beneficial. Our analysis leads to a recommendation to promote school-based sealant programs in underserved populations. / text