Dynamics of Oral Microbial Community Profiling During Severe Early Childhood Caries Development Monitored by PCR-DGGE

Objective: To monitor the longitudinal changes in oral microbial diversity of children with severe early childhood caries (S-ECC) compared to caries free (CF) controls.

Methods: Dental plaque samples of 12 children in each group at 8, 14, 20, 26 and 32 months of age were analysed. Total microbial genomic DNA was isolated from each sample, and PCR-denaturing gradient gel electrophoresis (DGGE) analyses were carried out.

Results: The number of bands was significantly higher in the CF group (18.17±4.91 bands) than in the S-ECC group (14.54±5.56 bands) at 32 months of age (P<0.05). A total of 21 genera were identified in all subjects, and there were no significant differences between the two groups at genus level. DGGE profiles showed that most of the clusters were constructed from one individual over time in the both groups.

Conclusions: The onset of S-ECC is accompanied by a decrease in microbial diversity. The overall composition of the microbiota is highly similar within an individual over time.