Periodontal disease severity is associated to pathogenic consortia comprising putative and candidate periodontal pathogens

Background: Complex interactions among distinct oral taxa within a dysbiotic periodontal
microenvironment are not fully understood.
Hypothesis/ gap statement: Based on a holistic concept of polymicrobial etiology, we
hypothesized that putative and novel periodontal pathogens are more frequently detected in
consortia than as single species in advanced forms of periodontal diseases (PD).
Aim: To correlate specific consortia of putative and novel periodontal pathogens with clinical
periodontal status.
Methodology. Subgingival biofilm was obtained from individuals with periodontal health
(113, PH), gingivitis (91, G) and periodontitis (209, P). Genomic DNA was purified and
Aggregatibacter actinomycetemcomitans (Aa), including Aa strain JP2, Porphyromonas
gingivalis (Pg), Dialister pneumosintes (Dp), and Filifactor alocis (Fa) were detected by
PCR. Configural frequency and logistic regression analyses were performed to correlate
microbial consortia with PD.
Results. Aa + Pg in the presence of Dp (phi = 0.240; χ2 = 11.9), p < 0.01), as well as Aa JP2
clone + Dp + Fa (phi = 0.186, χ2 = 4.6; p < 0.05) were predominant in advanced stages of P.
The consortium Aa + Fa + Dp was strongly related to deep pocketing and inflammation
(p<0.001). The best predictors of disease severity (80% accuracy) included older age (OR
1.11 [95% CI 1.07 – 1.15], p<0.001), Black/African-American ancestry (OR 1.89 [95% CI
1.19 – 2.99], p = 0.007, and high frequency of Aa + Pg + Dp (OR 3.04 [95% CI 1.49 – 6.22],
p = 0.002).
Conclusion. Specific microbial consortia of putative and novel periodontal pathogens,
associated with demographic parameters correlate with severe periodontitis, supporting the
multifactorial nature of the etiology and pathogenesis of PD.