Initial Study On The Horizontal Transmission Of Oral Streptococcus Mutans In Day-nursery Children

Dental caries is a virulent disease in children which causes premature loss of primary teeth. Streptococcus mutans (S.mutans) is regarded as a contributing etiological agent. Initial colonization of the microbe in children's oral cavities may influence their later caries experience. Previous study have supported that initial acquisition of S.mutans is from maternal transmission. Besides, there are other transmission sources of this microbe, intra-family or outside of the family. Nursery school is a locale where children have various contacts with each other but the same oral hygiene. The purpose of this study is to analyze genotypic diversity of oral S.mutans and find out horizontal transmission possibility of the microbe in day-nursery children and to provide instruction to prevention of childhood dental caries.Material and Metheds: 32 children in a nursery school in Chengdu were included in this study. They are in the same day-nursery class and aged between 3 and 4. After oral examination and record of their caries status, the plaque samples were scratched with sterilized toothpicks from teeth surface then cultured on MSBA plates. Clones with representative S.mutans-like were subcultured and identified to species level biochemically. AP-PCR fingerprinting was performed to distinguish genotypic diversity of those isolates. S.mutans isolates from different children with very similar amplicon profiles...