Bacterial Community Development in Experimental Gingivitis

Abstract

Current knowledge of the microbial composition of dental plaque in early gingivitis is based largely on microscopy and cultural methods, which do not provide a comprehensive description of oral microbial communities. This study used 454-pyrosequencing of the V1–V3 region of 16S rRNA genes (approximately 500 bp), and bacterial culture, to characterize the composition of plaque during the transition from periodontal health to gingivitis. A total of 20 healthy volunteers abstained from oral hygiene for two weeks, allowing plaque to accumulate and gingivitis to develop. Plaque samples were analyzed at baseline, and after one and two weeks. In addition, plaque samples from 20 chronic periodontitis patients were analyzed for cross-sectional comparison to the experimental gingivitis cohort. All of the healthy volunteers developed gingivitis after two weeks. Pyrosequencing yielded a final total of 344 267 sequences after filtering, with a mean length of 354 bases, that were clustered into an average of 299 species-level Operational Taxonomic Units (OTUs) per sample. Principal coordinates analysis (PCoA) plots revealed significant shifts in the bacterial community structure of plaque as gingivitis was induced, and community diversity increased significantly after two weeks. Changes in the relative abundance of OTUs during the transition from health to gingivitis were correlated to bleeding on probing (BoP) scores and resulted in the identification of new health- and gingivitis-associated taxa. Comparison of the healthy volunteers to the periodontitis patients also confirmed the association of a number of putative periodontal pathogens with chronic periodontitis. Taxa associated with gingivitis included Fusobacterium nucleatum subsp. polymorphum, Lachnospiraceae [G-2] sp. HOT100, Lautropia sp. HOTA94, and Prevotella oulorum, whilst Rothia dentocariosa was associated with periodontal health. Further study of these taxa is warranted and may lead to new therapeutic approaches to prevent periodontal disease.

The oral microbiome in human immunodeficiency virus (HIV)-positive individuals

“…The protocol used was as described previously (Kistler et al, 2013) with some minor modifications. PCR amplification of a fragment of the 16S rRNA gene, approximately 500 bp in length covering the V1-V3 hypervariable regions, was performed using composite fusion primers.…”

Predictive modeling of gingivitis severity and susceptibility via oral microbiota

“…Moreover, clinical diagnoses of gingivitis at present are typically based on individual observations and judgment by human examiners, where the results can be difficult to compare between patients and examiners. Furthermore, despite the complexity of oral microbial communities and the suspected polymicrobial nature of chronic oral infections, most population-wide surveys of gingivitisassociated microbiota have been limited to only a few culturable bacteria (for example, the 'red complex' including Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola) (Loe et al, 1965;Savitt and Socransky, 1984;Socransky et al, 1998;Haffajee et al, 2008;Igic et al, 2012;Eick et al, 2013) or have employed a small sampling size (Kistler et al, 2013).…”

Dental Plaques: Microbial Community of the Oral Cavity

“…The existence of a self-motivated balance between the micro flora and the host is very significant as the organisms contribute positively towards the host system. But when there breach in this balance the host system is compromised as a consequence of increase in microbial load resulting in the outbreak of diseases [41]. Hence there is a need for proficient plaque control techniques and effective treatments to sustain the normal dental micro biota at the desired levels that is well-suited in order to retain the favorable assets of these bacterial communities.…”