Aim: Various bacterial species are differentially prevalent in periodontal health, gingivitis or periodontitis. We tested the independent associations between three bacterial groupings and gingival inflammation in an epidemiological study.
Material and methods: In 706 Oral Infections and Vascular Disease Epidemiology Study (INVEST) participants > or =55 years, bleeding on probing (BoP), pocket depth (PD) and subgingival plaque samples (n=4866) were assessed in eight sites per mouth. Eleven bacterial species were quantitatively assayed and grouped as follows: (i) aetiologic burden (EB, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia); (ii) putative burden (PB, Campylobacter rectus, Eikenella corrodens, Fusobacterium nucleatum, Micromonas micros, Prevotella intermedia); (iii) health-associated burden (HAB, Actinomyces naeslundii, Veillonella parvula).
Results: After mutual adjustment for EB, PB and HAB, the BoP prevalence increased by 45% ( p<0.0001) across increasing quartiles of EB while BoP decreased by 13% ( p<0.0001) across increasing quartiles of HAB. Mean PD increased 0.8 mm and decreased 0.3 mm from the first to fourth quartiles of EB (p<0.0001) and HAB ( p<0.0001), respectively. Among 1214 plaque samples with fourth quartile EB, 60% were collected from sites with PD < or =3 mm.
Conclusion: Bacterial species believed to be aetiologically related to periodontitis were associated with BoP in sites with minimal PD and/or attachment level (AL). Species presumed to be associated with periodontal health demonstrated inverse associations with BoP.