The aim was to elucidate whether variables recorded in early childhood would have a long-lasting predictive value of poor dental health at the age of 10 years in a prospectively followed Finnish population-based cohort setting. The second aim was to find new tools for preventive work in order to improve dental health among children. Poor dental health (dmft + DMFT >or= 5) at 10 years of age was associated with child's nocturnal juice drinking at 18 months. It was associated with the following factors at age 3 years: frequent consumption of sweets; infrequent tooth brushing; plaque and caries on teeth. Of family factors, the following were significant: father's young age at birth of the child; mother's basic 9-year education; mother's caries (i.e. several carious teeth per year), and father's infrequent tooth brushing. Early childhood risk factors of poor dental health seem to be stable even after 10 years of life and the changing of teeth from primary to permanent ones. In preventive work, dental health care staff could offer support to those parents with risk factors in their child rearing tasks.