Abstract:

Objective:In order to prevent rampant caries in children, the predominant pathogenic bacteria of rampant caries in children were defined.Methods:The pathogenic bacteria of rampant carieswere isolated and identified in 30 childrenwith rampant caries, aged from 2 to 5 years old. Sampleswere collected from the caries of labial surfaces of maxillary anterior deciduous teeth, includ- ing caries lesions and caries-free smooth enamel surfaces. Plaque were obtained from the cervical third areas of the maxillary labial anterior deciduous tooth surfaces in children without rampant caries and caries-free children and served as controls respectively. The isolates were identified by colony morphology, biochemical tests and DNA base contents (mol percent G+C).Results:The prevalence of Streptococcus mutans (S.mutans) and Streptococcus sobrinus (S. sobrinus) in the plaque of caries lesions and the proportions of S. mutans and S. sobrinus in the plaque of 2 sampling sites of children with rampant caries were all significantly higher than those of children without rampant caries and caries-free children (P<0.05).Conclusion:S.mutans and S.sobrinus are predominant pathogenic bacteria in rampant caries in children.

Key words: rampant caries, children, S.mutans, S.sobrinus