Objective This study aimed to analyze the similarity of the oral bacteria community in 30 mother-child dyads via polymerase chain reaction(PCR)-based denaturing gradient gel electrophoresis. Methods Unstimulated saliva samples were obtained from 30 mother-child pairs:10 in caries-susceptive group, 10 in caries-moderate group, and 10 in caries-free group. DNAs were extracted for PCR amplification and denaturing gradient gel electrophoresis analysis. Results The compositions of the oral bacteria community in mother and child have a high degree of similarity. The oral bacteria community of children matched that of their mothers. The dice similarity coefficient of mother-child in the cariesfree group was more statistically significant compared with the two other groups(P
