A cohort study of caries incidence and baseline socioeconomic, clinical and demographic variables: a Kaplan-Meier survival analysis.

PURPOSE: To determine the incidence of dental caries and evaluate the influence of socioeconomic, clinical and demographic variables on the time for disease to appear in the permanent teeth after 3 years of follow-up. MATERIALS AND METHODS: The random sample of this cohort study consisted of 427 5-year-old preschool children attending 22 public preschools in Piracicaba, SP, Brazil. Dental caries was measured using the dmf/DMF indices. The Kaplan- Meier survival analysis method was used to study the isolated effect of socioeconomic, clinical and demographic variables on caries incidence after 3 years. A Cox proportional hazards regression model was built to test the influence of the variables collected at baseline on time to develop DMFT increment. RESULTS: Survival analysis showed that children without past caries experience in primary teeth at baseline remained caries free in permanent teeth for a longer period than children with past caries experience at baseline. The variables monthly family income, parents' educational level, number of people living in the household, home ownership and car ownership were not significant. CONCLUSION: Children who presented past caries experience in primary teeth at baseline are at greater risk of developing DMFT increment than children who have no past caries experience at baseline.

Dental caries and fluorosis prevalence and their relationship with socioeconomic and behavioural variables among 12-year-old schoolchildren.

PURPOSE: To evaluate caries experience and fluorosis prevalence in 12-year-old schoolchildren in Piracicaba, Brazil in 2007 and to verify the relationship of these changes with socioeconomic and behavioural variables. MATERIALS AND METHODS: The sample consisted of 724 schoolchildren from public and private schools. A calibrated dentist performed the examination under natural light using CPI probes and mirrors. The mean number of decayed, missing and filled permanent teeth (DMFT) and the SiC (Significant Caries Index) were determined for dental caries and the Thylstrup and Fejerskov index (T-F) for fluorosis. Socioeconomic and behavioural variables were collected by means of a questionnaire. Multiple logistic regression analyses were performed to verify the relationship of caries and fluorosis with socioeconomic and behavioural variables. RESULTS: The DMFT and SiC indices were 0.85 (±1.54) and 2.52 (±1.72). Fluorosis prevalence was 29.42%. The regression models showed that children whose families earned up to four minimum wages were 2.58 times more prone to having caries than those whose families earned over four minimum wages. Furthermore, children who visited the dentist were 4.27 times more likely to have DMFT > 0. However, for fluorosis, the regression model was not significant. CONCLUSIONS: The 12-year-old schoolchildren in Piracicaba presented very low caries prevalence. Significant associations were observed between the presence of caries, monthly family income and visiting the dentist. Considering dental fluorosis, the majority of the sample presented no clinical signs of fluorosis.

Assessment of caries experience in 12-year-old adolescents in Piracicaba, Sao Paulo, Brazil.

PURPOSE: The aim of the present study was to analyse the association between socioeconomic and behavioural factors and the presence of active non-cavitated caries lesions in 12-year-old adolescents in Piracicaba, São Paulo, Brazil. MATERIALS AND METHODS: A cross-sectional study was carried out in 1001, 12-year-old adolescents who were selected by the cluster sampling method. A modified version of the World Health Organization criteria for identifying lesions including white lesions (WL) in enamel was used. Information on behavioural and socioeconomic factors was obtained using a semi-structured questionnaire. The outcome variables were DMFS, DMFS+WL and WL. The data obtained were analysed using the chi-square test and a logistic regression model. RESULTS: The mean DMFS was 1.87 (SD = 3.05) and DMFS+WL was 2.27 (SD = 3.66). The logistic regression model showed that income was statistically significantly associated with DMFS, DMFS+WL and WL, whereas educational level of the father, number of residents in the house and number of dental visits were associated with DMFS and DMFS+WL. The onset of toothbrushing was associated with WL. CONCLUSIONS: The present study showed that economic factors are associated with all stages of caries development. In addition to these factors, family size, number of dental visits, educational level of the father and onset of toothbrushing could be considered markers of dental health risk.