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Updated: May 29, 2026

Oral Biofilm Sampling for Microbiome Analysis in Healthy Children
Published on: December 31, 2017
[Observation of genetic diversity in dental plaque of elder people with root caries]
Shan-fen Ma1, Jing-ping Liang, Yun-tao Jiang
1Department of Endodontics and Operative Dentistry, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China. mashanfen@yahoo.com.cn
Purpose:
Bacterial community in dental plaque of elder people was analyzed to learn about the microhabitat composition and diversity.
Methods:
Dental plaque samples were collected from 25 elders. PCR-based denaturing gradient gel electrophoresis (PCR-DGGE) was used to evaluate the microbial diversity by displaying PCR-generated 16SrDNA fragments that migrate at different distances, reflecting the different sequence of fragment. SPSS12.0 software was used to analyze the variance of genotypes between different groups of bacteria.
Results:
Genotypes of bacteria in dental plaques in the root caries group was significantly more than the other two groups. Crown caries group and caries-free group had no significant difference.
Conclusions:
The genetic diversity of the dental plaque microflora in the root caries group is significantly higher than coronal caries group and caries-free group.
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