Treatment of periodontitis reduces systemic inflammation in type 2 diabetes.

AIMS: To assess the impact of periodontal treatment on systemic inflammation in type 2 diabetes. MATERIALS AND METHODS: Adults with type 2 diabetes (n = 83) and without diabetes (controls, n = 75) were recruited, and participants with periodontitis received periodontal treatment and 12 months' follow-up. Biomarkers for periodontal inflammation (gingival crevicular fluid interleukin-6, tumour necrosis factor-α, interleukin-1ß, interferon-γ, matrix metalloproteinase-8, matrix metalloproteinase-9, adiponectin) and serum markers of inflammation and diabetes control (glycated haemoglobin, high sensitivity C-reactive protein, interleukin-6, tumour necrosis factor-α, interleukin-1ß, interferon-γ, leptin, adiponectin) were measured. Structural equation modelling was used to evaluate periodontal treatment effects on oral and systemic inflammation. RESULTS: Periodontal treatment resulted in significant improvements in clinical status and reductions in gingival crevicular fluid biomarkers from baseline to month 12. Structural equation modelling identified that, at baseline, individuals with diabetes and periodontitis had significantly higher systemic inflammation than non-diabetic controls with periodontitis (Δ = 0.20, p = .002), with no significant differences between groups for oral inflammation. There was a greater reduction in systemic inflammation following periodontal treatment in individuals with diabetes and periodontitis compared to those with periodontitis but not diabetes (Δ = -0.25, p = .01). CONCLUSIONS: Diabetes and periodontitis together appear to increase systemic inflammation, with evidence of reductions following periodontal treatment.

Smoking decreases structural and functional resilience in the subgingival ecosystem.

AIMS: Dysbiotic microbial communities underlie the aetiology of several oral diseases, especially in smokers. The ability of an ecosystem to rebound from the dysbiotic state and re-establish a health-compatible community, a characteristic known as resilience, plays an important role in susceptibility to future disease. The present investigation was undertaken to examine the effects of smoking on colonization dynamics and resilience in marginal and subgingival biofilms. MATERIALS AND METHODS: Marginal and subgingival plaque and gingival crevicular fluid samples were collected from 25 current and 25 never smokers with pre-existing gingivitis at baseline, following resolution, after 1, 2 4, 7, 14 and 21 days of undisturbed plaque formation and following resolution. 16S cloning and sequencing was used for bacterial identification and multiplexed bead-based flow cytometry was used to quantify the levels of 27 immune mediators. RESULTS: Smokers demonstrated an early pathogenic colonization that led to sustained pathogen enrichment with periodontal and respiratory pathogens, eliciting a florid immune response. Smokers also demonstrated greater abundance of pathogenic species, poor compositional correlation between marginal and subgingival ecosystems, and significantly greater pro-inflammatory responses following resolution of the second episode of disease. CONCLUSIONS: The ability of the subgingival microbiome to "reset" itself following episodes of disease is decreased in smokers, thereby lowering the resilience of the ecosystem and decreasing its resistance to future disease.

Clinical and subclinical effects of power brushing following experimental induction of biofilm overgrowth in subjects representing a spectrum of periodontal disease.

AIM: Investigate short-term effects of power brushing following experimental induction of biofilm overgrowth in periodontal disease states. MATERIALS AND METHODS: Overall, 175 subjects representing each of five biofilm-gingival interface (BGI) periodontal groups were enrolled in a single-blind, randomized study. After stent-induced biofilm overgrowth for 21 days subjects received either a manual or a power toothbrush to use during a 4 weeks resolution phase. At baseline and during induction and resolution, standard clinical parameters were measured. Subclinical parameters included multikine analysis of 13 salivary biomarkers and 16s Human Oral Microbe Identification Microarray (HOMIM) probe analysis of subgingival plaque samples. RESULTS: All groups exhibited significantly greater reductions in bleeding on probing (BOP) (p = 0.002), gingival index (GI) (p = 0.0007), pocket depth (PD) (p = 0.04) and plaque index (p = 0.001) with power brushing compared to manual. When BGI groups were combined to form a shallow PD (PD ≤ 3 mm) and a deep PD group (PD > 4 mm) power brushing reduced BOP and GI in subjects with both pocket depths. Power brushing significantly reduced IL-1ß levels at resolution while changes in bacterial levels showed non-significant trends between both brushing modalities. CONCLUSIONS: Short-term changes in select clinical parameters and subclinical salivary biomarkers may be useful in assessing efficacy of power brushing interventions in a spectrum of periodontal disease states.

Host-bacterial interactions during induction and resolution of experimental gingivitis in current smokers.

BACKGROUND: Changes in clinical profiles, microbial succession, and immune mediator fluctuations have all been separately examined during onset and resolution of experimental gingivitis in smokers. However, because both the bacterial challenge and the host response contribute to periodontal disease, the purpose of this investigation is to simultaneously examine clinical, bacterial, and immune changes that occur during the onset and resolution of disease in smokers. METHODS: Experimental gingivitis was induced in 15 smokers for 21 days, followed by treatment with a sonic toothbrush for 21 days. Marginal and subgingival plaque and gingival crevicular fluid samples were collected at baseline; after 7, 14, and 21 days of undisturbed plaque formation; and 21 days after reinstitution of brushing. 16S cloning and sequencing was used for bacterial quantification, and multiplexed bead-based flow cytometry was used to quantify the levels of 27 immune mediators. RESULTS: Onset of clinical gingivitis was preceded by significant changes in the marginal and subgingival biofilms, with a decrease in the abundance of early colonizers, namely, Streptococcus, Veillonella, and Pseudomonas, and an increase in levels of periodontopathogens, such as Treponema, Selenomonas, Parvimonas, Dialister, and Campylobacter. This was accompanied by a decrease in anti-inflammatory, chemokine, and T-helper 2 (Th2) responses and altered Th1/Th2 ratios. Although the bacterial communities continued to shift in the same direction after onset of clinical gingivitis and returned to baseline levels after resolution of disease, the anti-inflammatory, chemokine, and Th2 profiles demonstrated an increase from day 14 that continued even after clinical health was evident. CONCLUSION: Both marginal and subgingival biofilms in smokers are characterized by early acquisition of pathogenic organisms, which elicit a sustained host response that persists even after removal of the bacterial challenge.

Tobacco smoking affects bacterial acquisition and colonization in oral biofilms.

Recent evidence suggests that smoking affects the composition of the disease-associated subgingival biofilm, yet little is known about its effects during the formation of this biofilm. The present investigation was undertaken to examine the contributions of smoking to the composition and proinflammatory characteristics of the biofilm during de novo plaque formation. Marginal and subgingival plaque and gingival crevicular fluid samples were collected from 15 current smokers and from 15 individuals who had never smoked (nonsmokers) following 1, 2, 4, and 7 days of undisturbed plaque formation. 16S rRNA gene cloning and sequencing were used for bacterial identification, and multiplex bead-based flow cytometry was used to quantify the levels of 27 immune mediators. Smokers demonstrated a highly diverse, relatively unstable initial colonization of both marginal and subgingival biofilms, with lower niche saturation than that seen in nonsmokers. Periodontal pathogens belonging to the genera Fusobacterium, Cardiobacterium, Synergistes, and Selenomonas, as well as respiratory pathogens belonging to the genera Haemophilus and Pseudomonas, colonized the early biofilms of smokers and continued to persist over the observation period, suggesting that smoking favors early acquisition and colonization of pathogens in oral biofilms. Smokers also demonstrated an early proinflammatory response to this colonization, which persisted over 7 days. Further, a positive correlation between proinflammatory cytokine levels and commensal bacteria was observed in smokers but not in nonsmokers. Taken together, the data suggest that smoking influences both the composition of the nascent biofilm and the host response to this colonization.