Defense Date

2025

Document Type

Thesis

Degree Name

Master of Science in Dentistry

Department

Dentistry

First Advisor

Zhao Lin

Abstract

Background: Periodontitis is a common chronic inflammatory disease triggered by the dysbiosis of the subgingival microbiome. 16s rRNA sequencing has been used to profile the subgingival plaque samples in healthy and periodontitis subjects. Here, we have collected subgingival plaque samples from subjects and analyzed the microbiome profile from 16s rRNA sequencing. We hypothesized that periodontitis patients will have a different subgingival microbiome profile than that of healthy subjects.

Methods: Subgingival plaque samples were collected from periodontitis and healthy subjects who were indicated for periodontal surgeries (osseous resective and regenerative surgery for periodontitis patients or crown lengthening for healthy individuals). Fifty-five samples from 41 subjects were recruited for this study. Twenty-seven patients were included in the diseased group and 14 in the healthy group. In 14 subjects, samples were collected from two different pockets. DNA was extracted and 16S rRNA sequencing was performed. The microbial diversity and composition of bacterial samples were analyzed. Differential abundant microbes between healthy and periodontitis samples were also identified.

Results: About 550 taxa were identified from periodontal pockets, although most of them had low abundance. The microbiome in periodontitis subjects’ pockets showed a bigger richness and diversity than that in healthy samples (alpha diversity), however, healthy subgingival plaque had a larger variance among individuals (beta diversity). Differences can also be seen at different pockets from the same subjects. Microbes that are significantly present between healthy and periodontitis pockets were identified.

Conclusion: The microbiome of periodontitis pockets is significantly different from that in healthy pockets. These results suggest that future studies should focus on the microbial profile and dynamic interplay between the subgingival communities to help further understand the disease and aid in future treatments and diagnostics.

Rights

© Tareq Abdulrasoul

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

5-5-2025

Available for download on Tuesday, May 05, 2026

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