Porphyromonas gingivalis in saliva associates with chronic and aggressive periodontitis

Abstract

Objective: To characterize the salivary microbiota of patients with aggressive periodontitis, patients with chronica periodontitis and orally healthy individuals. Methods: A total of 81 unstimulated saliva samples from aggressive periodontitis patients (n = 31), chronic periodontitis patients (n = 25), and orally healthy controls (n = 25) were examined. The V1-V3 region of the 16S rDNA gene was sequenced with Illumina® MiSeq^TM, and sequences were annotated to the expanded Human Oral Microbiome Database (eHOMD). Results: A mean percentage of 97.6 (range: 89.8-99.7) of sequences could be identified at species level. Seven bacterial species, including Porphyromonas gingivalis, were identified with significantly higher relative abundance in saliva from aggressive periodontitis patients than in saliva from orally healthy controls. Salivary abundance of P. gingivalis could discriminate aggressive (AUC: 0.80, p = 0.0001) and chronic periodontitis (AUC: 0.72, p = 0.006) from healthy controls. Likewise, salivary presence of P. gingivalis was significantly associated with aggressive (p < 0.0001, RR: 8.1 (95% CI 2.1-31.2)) and chronic periodontitis (p = 0.002, RR: 6.5 (95% CI: 1.6-25.9)). Conclusion: Salivary presence and relative abundance of P. gingivalis associate with aggressive and chronic periodontitis, but do not discriminate between aggressive and chronic periodontitis.

Keywords: HOMINGS; Periodontal disease; Porphyromonas gingivalis; microbiota; periodontitis; saliva.

Figure 1.

Predominant bacterial genera. Mean relative abundance of predominant bacterial genera in patients with aggressive periodontitis, chronic periodontitis and orally healthy controls. The core salivary microbiota was defined as species/genus with a mean relative abundance >1% across sample. The predominant species/genera were compared using Mann-Whitney U test and Kruskall-Wallis test with Benjamini-Hochberg correction.

Figure 2.

Principal component analysis. Principal component analysis visualized two-dimensionally with axes expressed as two principal components values accounting for a cumulative value of (38.0%). Sample denotation: aggressive periodontitis patients: blue, chronic periodontitis patients: red, healthy controls: green.

Figure 3.

Correspondence analysis. Correspondence analysis visualized two-dimensionally with axes expressed as the two foremost inertia values accounting for a cumulative inertia of (20.1%). Sample denotation: aggressive periodontitis patients: blue, chronic periodontitis patients: red, healthy controls: green.