title: A cohort study of caries incidence and baseline socioeconomic, clinical and demographic variables: a Kaplan-Meier survival analysis.
abstract: OBJECTIVE
  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.
  
  
  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.
  
  
  CONCLUSIONS
  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.
authors: Karine Laura
authors: KL
authors: Cortellazzi
authors: Elaine Pereira
authors: EP
authors: Tagliaferro
authors: Stela Márcia
authors: SM
authors: Pereira
authors: Gláucia Maria
authors: GM
authors: Ambrosano
authors: Luciane Miranda
authors: LM
authors: Guerra
authors: Fabiana
authors: F
authors: de Vazquez
authors: Marcelo
authors: M
authors: de Meneghim
authors: Antonio Carlos
authors: AC
authors: Pereira
mesh_terms: D015331:Cohort Studies; D004245:DMF Index; D003731:Dental Caries / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D012307:Risk Factors; D016019:Survival Analysis