Bleeding on probing differentially relates to bacterial profiles: the Oral Infections and Vascular Disease Epidemiology Study

Metagenomic Insights Into the Subgingival Microbiome in Periodontal Health and Different Grades of Periodontitis

AIM

This cross-sectional study compared the subgingival microbiome in periodontal health (PH) and periodontitis, focusing on distinguishing Stage III Grade B periodontitis (PD-S3gB) and Stage III Grade C periodontitis (PD-S3gC) as defined by the 2018 Classification of Periodontitis.

METHODS

Subgingival samples from subjects with PH, PD-S3gB, and PD-S3gC were analyzed using metagenomic sequencing. Taxonomic and functional annotations were performed, followed by analyses of microbial diversity, differential abundance, interspecies networks, predictive modeling, and functional pathway enrichment.

RESULTS

Significant differences in both alpha and beta diversity were observed between PH and periodontitis. Several periodontal pathogens were more abundant in disease states, with Capnocytophaga granulosa and Capnocytophaga sp. CM59 enriched in PD-S3gC compared to PD-S3gB. The PD-S3gC group also exhibited a more complex microbial network with increased interspecies connectivity. An 11-species diagnostic model effectively distinguished PH, PD-S3gB, and PD-S3gC. Furthermore, pathways related to motility, chemotaxis, and methane metabolism were significantly enriched in periodontitis.

CONCLUSION

Distinct structural and functional differences in the subgingival microbiome characterize periodontal health and periodontitis. Periodontitis with a rapid rate of progression is marked by specific pathogen overgrowth and enhanced microbial interactions, supporting the development of microbiome-based diagnostics and personalized therapies.

TRIAL REGISTRATION

Chinese Clinical Trial Registration: ChiCTR2000039426.

Effect of implant abutment surface treatments on bacterial biofilm composition and structure

Background

For the long-term success of dental implants, implant abutment surface should promote the attachment of oral epithelial cells and reduce bacterial adhesion. Titanium nitride (TiN) coatings show antimicrobial properties. Nevertheless, there is a lack of clinical trials that assess the biofilm formation on TiN abutments in the context of clinical practice. Thus, the objective of this study was to evaluate the effect of different abutment surfaces (machined, TiN and TiN oxidized) on bacterial biofilm composition and structure.

Materials and methods

Implant abutments were connected to the dental implants. Bacterial communities were sampled at 1 and 60 days later. The relationship between surface, periodontal indices and bacterial community dynamics was assessed using 16S rRNA metagenomics. A total of 17 patients were involved in this study (14 included in final analyses: 15 machined, 16 TiN and 14 TiN oxidized abutments).

Results

No significant differences between surfaces were found considering taxa abundance, most alpha diversity metrics or community structure. Time showed a significant effect on diversity and also on the abundance of several bacterial taxa.

Conclusions

These results indicate that the effect of the three tested abutment surfaces on biofilm structure and composition was negligible, whereas patient and time exert strong influences on bacterial biofilm formation at different scales.

Salivary microbial shifting in hypertensive patients with chronic periodontitis after scaling and root surface debridement

OBJECTIVES

This study aimed to evaluate the impact of scaling and root surface debridement (SRP) on salivary bacterial counts and systolic and diastolic blood pressure in hypertensive patients with chronic periodontitis, with a focus on clinical significance.

METHODS

An observational trial included 24 chronic periodontitis patients, eleven of them were hypertensive patients. Non-surgical periodontal treatment was administered to all patients, with clinical parameters including gingival index (GI), plaque index (PI), and probing pocket depth (PPD) recorded. Saliva samples were collected before and after SRP to quantify total bacterial counts and specific bacterial counts.

RESULTS

Two months following SRP, PI and PPD in every subject under study demonstrated good responses. In hypertension patients, the salivary bacterial count was significantly higher following SRP (P = 0.0221). The incidence of Porphyromonas gingivalis in hypertension patients significantly decreased after treatment (P = 0.0386). Despite this, there was no discernible decrease in blood pressure following treatment.

CONCLUSIONS

SRP alone was ineffective in reducing overall bacterial counts, but P. gingivalis levels responded favorably. Regular periodontal assessment is crucial for hypertensive individuals to mitigate cardiovascular risk.

CLINICAL SIGNIFICANCE

Periodontal therapy in hypertensive patients may improve oral health but might not significantly impact blood pressure. Regular periodontal evaluation is essential for managing cardiovascular risk in hypertension.

Community dynamics of subgingival microbiome in periodontitis and targets for microbiome modulation therapy

The microbial aetiology for periodontitis has been widely studied and deciphered for more than a century. The evolving and changing concepts about periodontal microbiology can be attributed to continuously developing laboratory techniques. The current sequencing platforms have not only expanded the catalog of periodontal pathogens but have also facilitated the understanding of functional interactions of the ecological framework. However, the translation of this new knowledge to advance periodontal therapeutics is minimal. We contend that novel clinical interventions directed beyond conventional therapies need to be emphasized. A clear understanding of the structural and functional dynamics of subgingival microbiota is a pre-requisite for developing any microbiome-based interventions for applications in periodontal health care. In this review, we discuss the 16 s-rRNA gene sequencing-based knowledge of the subgingival microbial community structure, its interactions and functions, and our perspective on the potential to engineer it for periodontal therapeutics. Harnessing this next-generation sequencing-based knowledge, microbiome modulation therapies are poised to change microbiome therapeutics' face.

Correlation of COVID-19 with severity of periodontitis-A clinical and biochemical study

Background

Various conceptual hypotheses have been put forth to link association of COVID-19 with various chronic diseases such as periodontitis. Empirical evidence is still lacking to correlate the severity of COVID-19 with periodontal diseases.

Objectives

This study was undertaken with an objective to correlate COVID severity in systemically healthy patients suffering from periodontal diseases.

Materials and Methods

44 systemically healthy patients of both genders with minimum of 20 teeth in their oral cavity in age range of 20 to 50 years suffering from periodontitis were recruited and categorised into four stages as per American Academy of Periodontology (AAP) 2017 classification for periodontitis. Serum C-reactive protein (CRP) levels and periodontal disease parameters of all the patients were measured. Because of COVID-19 and the nationwide lockdown, the dental practice was highly affected. With the help of self-designed online questionnaire information regarding COVID-19 infection and associated symptoms were recorded. Cases were categorized into five groups based on the World Health Organization clinical progression scale of COVID severity.

Results

All the patients suffering from COVID disease in moderate and severe forms had increased probing pocket depth, clinical attachment level, and raised serum C-reactive protein levels as compared to patients who were uninfected or suffering from mild COVID disease and the results were statistically significant.

Conclusion

Prioritisation and Implementation of periodontal treatment as a preventive measure for COVID-19 should be done. A positive correlation is observed between the severity of periodontitis and COVID-19.

Electric and Manual Oral Hygiene Routines Affect Plaque Index Score Differently

This cross-sectional study aimed to examine the oral hygiene behaviors in the general population and identify factors affecting oral hygiene behaviors and plaque removal efficacy. A survey was distributed to patients through 11 dental practices in Japan, and each patient’s plaque index score (PIS) was recorded. In total, 1184 patients participated (521 women and 660 men), with 84.04% using manual toothbrushes (MTBs) and 15.96% using electric toothbrushes (ETBs). ETB users had a significantly lower PIS compared to MTB users (p = 0.0017). In addition, a statistically significant difference in the PIS was detected in relation to the frequency of brushing per day (≥2 times) and time spent on brushing (≥1 min). Some MTB users spent less than 1 min brushing, while all ETB users spent at least 1 min brushing, and extended brushing periods significantly improved the PIS for the MTB users. MTB users tend to replace brush heads more frequently than ETB users, and the frequency of replacement affected the PIS significantly (p < 0.01) for the MTB users. The status of dental treatment (first visit, in treatment versus recall) also significantly affected the PIS (p < 0.01). The ETB was more effective than the MTB in terms of better plaque removal and reduced frequency of brush head replacement.

Periodontal status and quality of life in pregnant women with both overweight/obesity and hypertension: A cross-sectional study

Background

The aim of this study was to assess the periodontal condition and quality of life of pregnant women affected with both overweight/obesity and arterial hypertension.

Material and Methods

Pregnant women were dived into three groups: with overweight/obesity and hypertension (G1 = 23), with overweight/obesity without hypertension (G2 = 31) and with normal BMI and without hypertension (G3 = 38). They were evaluated regarding: contextual variables (age, socioeconomic level and anthropometric parameters); periodontal status; and quality of life (adapted version of Oral Health Impact Profile – OHIP-14). ANOVA, Kruskal-Wallis, chi-square and binary logistic regression model were adopted (p< 0.05).

Results

There were no intergroup differences for age (p = 0.700), education level (p = 0.119) and gestational weight gain (p = 0.415), nevertheless G2 differed from G3 regarding household monthly income (p = 0.040). G2 had higher prevalence of bleeding on probing than G3 (p = 0.001), but G1 and G2 presented higher prevalence of periodontitis (p< 0.001). Household monthly income (adjusted OR = 0.71; 95% CI = 0.52 - 0.98; p = 0.038) and hypertension (adjusted OR = 3.70; 95% CI = 1.16 - 11.80; p = 0.026) remained in the final logistic regression model [X2(4) = 21.79; p = 0.0002; R2 of Nagelkerke = 0.284]. G1 showed worse impact on quality of life, mainly regarding physical pain (p< 0 .001), psychological discomfort (p< 0 .001), physical disability (p< 0 .001), social disability (p = 0.005) and handicap (p< 0 .001).

Conclusions

In conclusion, maternal excessive weight is associated with periodontitis during pregnancy. Moreover, the presence of hypertension in overweight pregnant women seems to be determinant to negatively influence their quality of life, resulting in physical, psychological and social damages.

Key words:Hypertension, obesity, overweight, periodontitis, quality of life.

Effect of periodontal treatment on preclinical Alzheimer's disease-Results of a trial emulation approach

INTRODUCTION

We investigated the relationship between periodontal treatment and pre-clinical Alzheimer's disease (AD).

METHODS

In this quasi-experimental design, 177 periodontally treated patients from the "Greifswald Approach to Individualized Medicine" cohort, which used the same protocols as the population-based Study of Health in Pomerania TREND (SHIP-TREND), and 409 untreated subjects from SHIP-TREND were analyzed. Subjects were younger than 60 years at the magnetic resonance imaging examination, with a median observation period of 7.3 years. Imaging markers for brain atrophy in late-onset AD and brain aging were used as the outcomes.

RESULTS

Robust to sensitivity analyses, periodontal treatment had a favorable effect on AD-related brain atrophy (-0.41; 95% confidence interval: -0.70 to -0.12; P = .0051), which corresponds to a shift from the 50th to the 37th percentile of the outcome distribution. For brain aging, the treatment effect was uncertain.

CONCLUSION

Periodontitis is related to pre-clinical AD in our population.

Effects of a β2-adrenergic receptor blocker on experimental periodontitis in spontaneously hypertensive rats

AIMS

Recent studies have reported a relationship between periodontal disease and hypertension, and previous evidence suggests that the sympathetic nervous system plays an important role in the control of bone metabolism. This study sought to evaluate the effect of the beta-2 adrenergic receptor (β2-AR) blocker butoxamine on experimental periodontitis in a rat model.

MATERIALS AND METHODS

Wistar-Kyoto and spontaneously hypertensive rats (n = 6 per group) were orally administered butoxamine 1 mg/kg/day and experimental periodontitis was induced by applying an orthodontic ligature wire. The rats were sacrificed after 4 weeks and the residual alveolar bone was measured using micro-computed tomography (micro-CT) imaging analysis software for histological analysis.

KEY FINDINGS

Micro-CT imaging analysis showed a higher ratio of residual alveolar bone, BV/TV, and Tb.N in both Wistar-Kyoto and spontaneously hypertensive rats treated with butoxamine compared with the corresponding control rats. In histological analysis, compared with the Wistar-Kyoto and spontaneously hypertensive rat control groups, the corresponding butoxamine-treated groups showed a lower ratio of attachment level, lower values of osteoclast number and surface.

SIGNIFICANCE

β2-AR blockers maintained the alveolar bone mass and attachment level by suppressing osteoclast activity. Thus, β2-AR blockers may be effective in preventing periodontitis.

Association Between Periodontitis and Blood Pressure Highlighted in Systemically Healthy Individuals: Results From a Nested Case-Control Study

[Figure: see text].

Association Between Arterial Hypertension and Periodontal Status in Morbidly Obese Patients Who Are Candidates for Bariatric Surgery

Objective

This study aimed to compare the systemic and periodontal conditions between morbidly obese patients with and without hypertension who were candidates for bariatric surgery.

Methods

The study cohort had 111 morbidly obese patients stratified into two groups: patients with (G1 = 54) and without (G2 = 57) arterial hypertension. The following characteristics were compared between the two groups: (i) education level; (ii) anthropometric parameters [weight, height, body mass index (BMI), waist and hip circumferences and waist-to-hip ratio (WHR)]; (iii) risk of developing cardiovascular diseases (based on patients’ sex, age and WHR); (iv) behaviours regarding oral hygiene; and (v) periodontal status. The t-test, Mann–Whitney U-test, chi-square test and logistic regression were applied, with a significance level of 5%.

Results

Patients in G1 had a lower level of education (P = 0.002). There were no intergroup differences for weight (P = 0.211), height (P = 0.126), BMI (P = 0.551), waist circumference (P = 0.859) and WHR (P = 0.067); however, patients in G2 had a smaller hip circumference (P = 0.029), and 78% of patients in G1 had a high/very high risk of developing cardiovascular diseases. The prevalence of periodontitis was 72.2% (n = 39) in G1 and 38.6% (n = 22) in G2. On logistic regression analysis, age [adjusted odds ratio (OR) = 1.07; 95% CI = 1.01–1.13; P = 0.008) and the presence of arterial hypertension (OR = 2.77; 95% CI = 1.17–6.56; P = 0.019) were identified as the independent variables associated with periodontitis.

Conclusion

Morbid obesity and arterial hypertension are associated with a higher prevalence of cardiovascular diseases. Moreover, morbidly obese patients with hypertension have a higher prevalence of periodontitis and greater severity of periodontal disease than those without hypertension.

Eye on the Enigmatic Link: Dysbiotic Oral Pathogens in Ocular Diseases; The Flip Side

Mouth and associated structures were regarded as separate entities from the rest of the body. However, there is a paradigm shift in this conception and oral health is now considered as a fundamental part of overall well-being. In recent years, the subject of oral-foci of infection has attained a resurgence in terms of systemic morbidities while limited observations denote the implication of chronic oral inflammation in the pathogenesis of eye diseases. Hitherto, there is a paucity for mechanistic insights underlying the reported link between periodontal disease (PD) and ocular comorbidities. In light of prevailing scientific evidence, this review article will focus on the understudied theme, that is, the impact of oral dysbiosis in the induction and/or progression of inflammatory eye diseases like diabetic retinopathy, scleritis, uveitis, glaucoma, age-related macular degeneration (AMD). Furthermore, the plausible mechanisms by which periodontal microbiota may trigger immune dysfunction in the Oro-optic-network and promote the development of PD-associated AMD have been discussed.

Periodontitis is associated with hypertension: a systematic review and meta-analysis

Recent evidence suggests a link between periodontitis (PD) and hypertension, but the nature of this association remains unclear. The overall aim of this review was to critically appraise the evidence linking these two common disorders. Systematic search was conducted for studies published up to December 2018. Prevalence of hypertension in patients with PD (moderate/severe groups) vs. those without PD (non-PD) was the primary outcome. Additional outcomes included adjusted mean difference in systolic (SBP) and diastolic (DBP) blood pressure (BP) levels in PD vs. non-PD, assessment of biomarkers in PD and hypertension, and BP changes after periodontal therapy. From 81 studies selected, 40 were included in quantitative meta-analyses. Diagnoses of moderate-severe PD [odds ratio (OR) = 1.22; 95% confidence interval (CI): 1.10-1.35] and severe PD (OR = 1.49; 95% CI: 1.09-2.05) were associated with hypertension. Prospective studies confirmed PD diagnosis increased likelihood of hypertension occurrence (OR = 1.68; 95% CI: 0.85-3.35). Patients with PD exhibited higher mean SBP [weighted mean difference (WMD) of 4.49 mmHg; 95% CI: 2.88-6.11] and DBP (2.03 mmHg; 95% CI: 1.25-2.81) when compared with non-PD. Lastly, only 5 out of 12 interventional studies confirmed a reduction in BP following periodontal therapy, ranging from 3 to 12.5 mmHg of SBP and from 0 to 10 mmHg of DBP. PD is associated with increased odds of hypertension (SORT C) and higher SBP/DBP levels. The evidence suggesting that PD therapy could reduce BP is inconclusive. Although additional research is warranted on this association, these results suggest that oral health assessment and management of PD could not only improve oral/overall health and quality of life but also be of relevance in the management of patients with hypertension.

Microbial Composition of Oral Biofilms after Visible Light and Water-Filtered Infrared a Radiation (VIS+wIRA) in Combination with Indocyanine Green (ICG) as Photosensitizer

In view of increasing antibiotic resistance, antimicrobial photodynamic therapy (aPDT) is an alternative treatment method used to eradicate the microbial community of oral biofilms that can be responsible for different oral infections. In order to investigate changes in the microbial composition after application of aPDT with visible light and water-filtered infrared A (VIS+wIRA) in combination with indocyanine green (ICG), oral microorganisms of the initial and mature biofilm were evaluated by mass spectrometry (MALDI-TOF-MS). To determine surviving microorganisms using MALDI-TOF-MS, an in situ biofilm was irradiated with VIS+wIRA for five minutes in the presence of ICG (300 and 450 µg/mL, respectively). Treatment with chlorhexidine (0.2%) served as positive control. Identified microorganisms of the initial biofilm treated with ICG showed a clear reduction in diversity. The microbial composition of the mature oral biofilm also showed changes after the implementation of aPDT, which mainly resulted in a shift in the percentage of bacterial species. The resulting destruction of the microbial balance within the oral biofilm by aPDT using VIS+wIRA and ICG can be seen as an advantageous supplementary approach in the adjunctive treatment of periodontitis and peri-implantitis.

Analysis of risk indicators for prevalence of peri-implant diseases in Turkish population

Background

The aim of this cross-sectional study was (1) to determine the prevalence of peri-implant mucositis and peri-implantitis and (2) to reveal the risk indicators associated with peri-implant diseases. The second point was to investigate the role of keratinized mucosa on peri-implant health.

Materials and methods

Three hundred and eighty-two subjects who were treated with 1415 dental implants between 2011–2017 were clinically evaluated. Patients’ medical and dental history, as well as implant details, were recorded. Peri-implant examination included probing pocket depth (PPD), bleeding on probing (BoP), plaque index (PI), gingival index (GI), and keratinized tissue width. Furthermore, the patient (sex, age, and smoking) and implant/prosthesis-related factors (surface characteristic, time in function, design of prosthesis etc.) were evaluated. Implants were classified into three groups: healthy, peri-implant mucositis, and peri-implantitis. Uni- and multi-variate regression analyses were utilized for statistics.

Results

41.1% (n = 157) and 36.9% (n = 84) of patients had mucositis and peri-implantitis, respectively. 53.6% (n = 758) of implants (95%CI 80.2–90.4) had mucositis, and 21.7% (n = 307) had peri-implantitis. Patients with a maintenance < 2/year (OR = 2.576), having periodontitis (OR = 3.342) and higher PI (OR = 3.046) had significant associations with the development of peri-implant mucositis. Significant ORs were determined for peri-implantitis with patients having maintenance < 2/year (OR = 2.048), having number of implants ≥ 4 (OR = 2.103), diagnosed with periodontitis (OR = 3.295), and higher PI (OR = 7.055). Keratinized tissue width < 2 mm (ORs = 5389/8.013), PPD (ORs = 1.570/8.338), PI (ORs = 6.726/5.205), and BoP (ORs = 3.645/4.353) independent variables were significantly associated with both peri-implant mucositis and peri-implantitis at implant level, respectively.

Conclusions

Within the limits of this study, the prevalence of mucositis and peri-implantitis was shown to be high in Turkish population. Furthermore, increased risk for peri-implantitis was identified in patients having maintenance < 2/year, presence of periodontitis, poor plaque control, and having number of implants ≥ 4. Less keratinized tissue (< 2 mm), PPD, and BoP were also risk indicators for peri-implantitis development.

Gingival tissue human beta-defensin levels in relation to infection and inflammation

AIM

To profile gingival tissue levels of human beta-defensin (hBD)-2 and hBD-3 in relation to gingival inflammation, Th17-related cytokine concentrations, Porphyromonas gingivalis counts, and gingipain and total protease activities.

MATERIALS AND METHODS

Gingival tissue and subgingival plaque samples were collected from 21 periodontitis patients including 48 periodontal pocket sites with marginal, mild, or moderate to severe inflammation. hBD levels were determined by immunodetection, P. gingivalis counts with real-time polymerase chain reaction, protease activities with fluorogenic substrates, and cytokine concentrations with Luminex technique. Data were statistically analysed using Kruskal-Wallis and Mann-Whitney U tests and Spearman correlation coefficients.

RESULTS

Subgingival plaque counts of P. gingivalis (p = .001) and gingipain activity (p < .001), as well as interleukin (IL)-1β (p = .012), IL-10 (p = .024), IL-17A (p = .002), IL-17F (p = .006), and IL-23 (p = .036) concentrations were elevated in severely inflamed sites, whereas no change was observed in hBD-2 and hBD-3 levels. Negative correlations were found between protease activity and hBD-2 (p = .033) and hBD-3(p = .003) levels.

CONCLUSIONS

Shift in gingival inflammation from marginal to mild stage is related to elevations in subgingival plaque P. gingivalis counts and gingipain activity, but not to tissue hBD levels. Negative correlations between hBDs and total protease activity suggest the degradation of these antimicrobial peptides in progressed inflammation.

Reducing uncertainty in estimating associations of oral exposures with Helicobacter pylori serology in the general population

AIM

Evidence for reducing Helicobacter (H.) pylori by periodontal therapy comes from small studies in China, limiting generalizability. To estimate the association between periodontal disease and anti-H. pylori IgG titer levels in a European country, we used population-based data from the Study of Health in Pomerania.

MATERIALS AND METHODS

For pocket depth as the primary exposure, we restricted the age range to participants younger than 60 years (n = 2,481) to avoid selection bias due to edentulism in this cross-sectional study. For the full age range up to 81 years, we chose the number of missing teeth (n = 3,705).

RESULTS

The association between pocket depth and the outcome was weak. Given the ceiling effect for the number of missing teeth (ordinal logistic regression; odds ratio of the interquartile range effect = 1.6; 95% CI: 1.3-1.9; p-value for linearity = 0.005), we checked whether wearing removable dental prosthesis was associated with higher anti-H. pylori IgG titer levels (odds ratio = 1.3; 95% CI: 1.1-1.5).

CONCLUSIONS

Tooth loss and wearing removable dental prosthesis were weakly to moderately associated with higher anti-H. pylori IgG titer levels in the general population of a European country.

Association of salivary peroxidase activity and concentration with periodontal health: A validity study

AIM

Whereas the relationship between myeloperoxidase and periodontitis has been widely examined that between salivary peroxidase and periodontitis has received little attention. We examined how periodontitis depends on both salivary peroxidase activity and concentration.

MATERIALS AND METHODS

A full mouth, clinical assessment of probing depth was performed in a sample of 46 participants aged 25-54 years. To minimise bias, these data were corrected by data from the general population (Study of Health in Pomerania). Using five repeated measurements of activity and concentration over 1 day, we assessed daily biological variability and increased the reliability of salivary peroxidase measurements.

RESULTS

Salivary peroxidase activity was associated with probing depth (interquartile range effect = -0.48; robust estimates of 95% confidence interval: -0.90 to -0.31; p = .0052), and its effect was not confounded by salivary peroxidase concentration. In turn, the effect of salivary peroxidase concentration was confounded by salivary peroxidase activity, and it was smaller than that of activity.

CONCLUSIONS

We found an inverse association between salivary peroxidase activity and probing depth. Thus, our results imply that salivary peroxidase activity could be a protective factor against periodontitis. However, large, well-designed studies are needed to explore the causal mechanisms of this association.

The subgingival microbiome, systemic inflammation and insulin resistance: The Oral Infections, Glucose Intolerance and Insulin Resistance Study

BACKGROUND

Inflammation might link microbial exposures to insulin resistance. We investigated the cross-sectional association between periodontal microbiota, inflammation and insulin resistance.

METHODS

The Oral Infections, Glucose Intolerance and Insulin Resistance Study (ORIGINS) enrolled 152 diabetes-free adults (77% female) aged 20-55 years (mean = 34 ± 10). Three hundred and four subgingival plaque samples were analysed using the Human Oral Microbe Identification Microarray to measure the relative abundances of 379 taxa. C-reactive protein, interleukin-6, tumour necrosis factor-α and adiponectin were assessed from venous blood and their z-scores were summed to create an inflammatory score (IS). Insulin resistance was defined via the HOMA-IR. Associations between the microbiota and both inflammation and HOMA-IR were explored using multivariable linear regressions; mediation analyses assessed the proportion of the association explained by inflammation.

RESULTS

The IS was inversely associated with Actinobacteria and Proteobacteria and positively associated with Firmicutes and TM7 (p-values < 0.05). Proteobacteria levels were associated with insulin resistance (p < 0.05). Inflammation explained 30-98% of the observed associations between levels of Actinobacteria, Proteobacteria or Firmicutes and insulin resistance (p-values < 0.05). Eighteen individual taxa were associated with inflammation (p < 0.05) and 22 with insulin resistance (p < 0.05). No findings for individual taxa met Bonferroni-adjusted statistical significance.

CONCLUSION

Bacterial measures were related to inflammation and insulin resistance among diabetes-free adults.

Periodontal Bacteria and Prediabetes Prevalence in ORIGINS: The Oral Infections, Glucose Intolerance, and Insulin Resistance Study

Periodontitis and type 2 diabetes mellitus are known to be associated. The relationship between periodontal microbiota and early diabetes risk has not been studied. We investigated the association between periodontal bacteria and prediabetes prevalence among diabetes-free adults. ORIGINS (the Oral Infections, Glucose Intolerance and Insulin Resistance Study) cross sectionally enrolled 300 diabetes-free adults aged 20 to 55 y (mean ± SD, 34 ± 10 y; 77% female). Prediabetes was defined as follows: 1) hemoglobin A1c values ranging from 5.7% to 6.4% or 2) fasting plasma glucose ranging from 100 to 125 mg/dL. In 1,188 subgingival plaque samples, 11 bacterial species were assessed at baseline, including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Actinomyces naeslundii. Full-mouth clinical periodontal examinations were performed, and participants were defined as having no/mild periodontitis vs. moderate/severe periodontitis per the definition of the Centers for Disease Control and Prevention / American Academy of Periodontology. Modified Poisson regression evaluated prediabetes prevalence across bacterial tertiles. Prevalence ratios and 95% confidence intervals for third vs. first tertiles are presented. All analyses were adjusted for cardiometabolic risk factors. All results presented currently arise from the baseline cross section. Prediabetes prevalence was 18%, and 58% of participants had moderate/severe periodontitis. Prevalence ratios (95% confidence intervals) summarizing associations between bacterial levels and prediabetes were as follows: A. actinomycetemcomitans, 2.48 (1.34, 4.58), P = 0.004; P. gingivalis, 3.41 (1.78, 6.58), P = 0.0003; T. denticola, 1.99 (0.992, 4.00), P = 0.052; T. forsythia, 1.95 (1.0, 3.84), P = 0.05; A. naeslundii, 0.46 (0.25, 0.85), P = 0.01. The prevalence ratio for prediabetes among participants with moderate/severe vs. no/mild periodontitis was 1.47 (0.78, 2.74), P = 0.23. Higher colonization levels of specific periodontal microbiota are associated with higher prediabetes prevalence among diabetes-free adults.

Changes in the supragingival microbiota surrounding brackets of upper central incisors during orthodontic treatment

OBJECTIVE

The aim of this study was to determine how fixed orthodontic appliances affect microbiota of supragingival plaque over 5 months.

MATERIALS AND METHODS

Twenty individuals of Scandinavian origin, aged 10-16 years, were included. All subjects were fitted with fixed orthodontic appliances in both the maxillary and mandibular tooth arches. Pooled supragingival plaque samples from the labial surface of the two maxillary central incisors were collected before bonding (T1) and afterwards at 4 weeks (T2), 3 months (T3) and 5 months (T4). The plaque index (PI) was recorded for each sampling. The gingival status was documented at T1 and T4 by using clinical photographs. Plaque microbiota was identified using the Human Oral Microbe Identification Microarray (HOMIM).

RESULTS

Increased plaque levels were recorded after bonding, however the increase was not significant. The prevalence of gingivitis at the maxillary central incisors increased from 25% at T1 to 74% at T4. No significant changes of the plaque microbiota from the sample area were detected during the 5-month period. Trends toward a microbiota containing more periodontitis- and caries-associated bacteria were detected.

CONCLUSIONS

Although trends toward a microbiota containing more periodontitis- and caries-associated bacteria were detected, the changes were not severe enough to be significant. Treatment with fixed orthodontics does not necessarily shift the microbiota to a more pathogenic composition.

Changes in clinical and microbiological periodontal profiles relate to progression of carotid intima-media thickness: the Oral Infections and Vascular Disease Epidemiology study

Background

No prospective studies exist on the relationship between change in periodontal clinical and microbiological status and progression of carotid atherosclerosis.

Methods and Results

The Oral Infections and Vascular Disease Epidemiology Study examined 420 participants at baseline (68±8 years old) and follow‐up. Over a 3‐year median follow‐up time, clinical probing depth (PD) measurements were made at 75 766 periodontal sites, and 5008 subgingival samples were collected from dentate participants (average of 7 samples/subject per visit over 2 visits) and quantitatively assessed for 11 known periodontal bacterial species by DNA‐DNA checkerboard hybridization. Common carotid artery intima‐medial thickness (CCA‐IMT) was measured using high‐resolution ultrasound. In 2 separate analyses, change in periodontal status (follow‐up to baseline), defined as (1) longitudinal change in the extent of sites with a ≥3‐mm probing depth (Δ%PD≥3) and (2) longitudinal change in the relative predominance of bacteria causative of periodontal disease over other bacteria in the subgingival plaque (Δetiologic dominance), was regressed on longitudinal CCA‐IMT progression adjusting for age, sex, race/ethnicity, diabetes, smoking status, education, body mass index, systolic blood pressure, and low‐density lipoprotein cholesterol and high‐density lipoprotein cholesterol. Mean (SE) CCA‐IMT increased during follow‐up by 0.139±0.008 mm. Longitudinal IMT progression attenuated with improvement in clinical or microbial periodontal status. Mean CCA‐IMT progression varied inversely across quartiles of longitudinal improvement in clinical periodontal status (Δ%PD≥3) by 0.18 (0.02), 0.16 (0.01), 0.14 (0.01), and 0.07 (0.01) mm (P for trend<0.0001). Likewise, mean CCA‐IMT increased by 0.20 (0.02), 0.18 (0.02), 0.15 (0.02), and 0.12 (0.02) mm (P<0.0001) across quartiles of longitudinal improvement in periodontal microbial status (Δetiologic dominance).

Conclusion

Longitudinal improvement in clinical and microbial periodontal status is related to a decreased rate of carotid artery IMT progression at 3‐year average follow‐up.

Salivary diagnostics for periodontal diseases

BACKGROUND

and Overview The use of salivary diagnostics continues to develop and advance the field of risk determination for periodontal diseases. Researchers are investigating genetic, microbial and protein biomarkers with the objective of translating findings to such aspects of clinical care as broad patient screening, monitoring and treatment planning.

METHODS

/st> In this review, the author briefly explores currently available salivary diagnostics used to identify bacteria prevalent in periodontal disease, and focuses on the future development and use of a variety of rapid disease detection platforms, such as lab-on-a-chip, as a point-of-care device for identification of patients' risk.

CONCLUSIONS

and

CLINICAL IMPLICATIONS

/st> Several diagnostic tests are commercially available, and point-of-care tests are under development. However, challenges remain regarding the introduction of these technologies to clinical practice and adoption by dental practitioners for promotion of personalized oral health care.

Periodontal infection, systemic inflammation, and insulin resistance: results from the continuous National Health and Nutrition Examination Survey (NHANES) 1999-2004

OBJECTIVE

Adverse microbial exposures might contribute to diabetogenesis. We hypothesized that clinical periodontal disease (a manifestation of microbial exposures in dysbiotic biofilms) would be related to insulin resistance among diabetes-free participants. The roles of inflammatory mediation and effect modification were also studied.

RESEARCH DESIGN AND METHODS

The continuous National Health and Nutrition Examination Survey 1999-2004 enrolled 3,616 participants (51% women) who received a periodontal examination and fasting blood draw. Participants were mean age (± SD) 43 ± 17 years and 28% Hispanic, 52% Caucasian, 17% African American, and 3% other. Log-transformed values of the homeostasis model assessment of insulin resistance (HOMA-IR) or HOMA-IR ≥3.30 (75th percentile) were regressed across full-mouth periodontal probing depth (PD) levels using linear and logistic models. White blood cell (WBC) count and C-reactive protein (CRP) were considered as either mediators or effect modifiers in separate analyses. Risk ratios (RRs) stem from marginal predictions derived from the logistic model. Results were adjusted for multiple periodontal disease and insulin resistance risk factors.

RESULTS

In linear regression, geometric mean HOMA-IR levels increased by 1.04 for every 1-mm PD increase (P = 0.007). WBC mediated 6% of the association (P < 0.05). Among participants with WBC ≤6.4 × 10(9), PD was unrelated to HOMA-IR ≥3.30. Fourth-quartile PD was associated with HOMA-IR ≥3.30 among participants with WBC >7.9 × 10(9); RR 2.60 (1.36-4.97) (P for interaction = 0.05). Findings were similar among participants with CRP >3.0 mg/L (P for interaction = 0.04).

CONCLUSIONS

Periodontal infection was associated with insulin resistance in a nationally representative U.S. sample of diabetes-free adults. These data support the role of inflammation as both mediator and effect modifier of the association.

Association between oral health and gastric precancerous lesions

Although recent studies have suggested that tooth loss is positively related to the risk of gastric non-cardia cancer, the underlying oral health conditions potentially responsible for the association remain unknown. We investigated whether clinical and behavioral measures of oral health are associated with the risk of gastric precancerous lesions. We conducted a cross-sectional study of 131 patients undergoing upper gastrointestinal endoscopy. Cases were defined as those with gastric precancerous lesions including intestinal metaplasia or chronic atrophic gastritis on the basis of standard biopsy review. A validated structured questionnaire was administered to obtain information on oral health behaviors. A comprehensive clinical oral health examination was performed on a subset of 91 patients to evaluate for periodontal disease and dental caries experience. A total of 41 (31%) cases of gastric precancerous lesions were identified. Compared with non-cases, cases were significantly more likely to not floss their teeth [odds ratio (OR) = 2.89, 95% confidence interval (CI): 1.09-7.64], adjusting for age, sex, race, body mass index, smoking status, educational attainment and Helicobacter pylori status in serum. Among participants who completed the oral examination, cases (n = 28) were more likely to have a higher percentage of sites with gingival bleeding than non-cases [OR = 2.63, 95% CI: 1.37-5.05 for a standard deviation increase in bleeding sites (equivalent to 19.7%)], independent of potential confounders. Our findings demonstrate that specific oral health conditions and behaviors such as gingival bleeding and tooth flossing are associated with gastric precancerous lesions.

A prospective cohort study of periodontal disease measures and cardiovascular disease markers in HIV-infected adults

The determinants of HIV-associated cardiovascular disease (CVD) are not well understood. Periodontal disease (PD) has been linked to CVD but this connection has not been examined in HIV infection. We followed a cohort of HIV-infected adults to ascertain whether PD was associated with carotid artery intima media thickness (IMT) and brachial artery flow-mediated dilation (FMD). We performed a longitudinal observational study of HIV-infected adults on HAART for <2 years with no known heart disease. PD was characterized clinically and microbiologically. Cardiovascular disease was assessed by IMT/FMD. Linear mixed models assessed cross-sectional and longitudinal associations between PD and FMD/IMT. Forty three HIV(+) adults completed a median of 24 (6-44) months on the study. Defining delta to be the change in a variable between baseline and a follow-up time, longitudinally, on average and after adjusting for change in time, CVD-specific and HIV-specific potential confounding covariates, a 1-log(10) increase in delta Porphyromonas gingivalis was associated with a 0.013 mm increase in delta IMT (95% CI: 0.0006-0.0262; p=0.04). After adjusting for the same potential confounding covariates, a 10% increase in delta gingival recession was associated with a 2.3% increase in delta FMD (95% CI: 0.4-4.2; p=0.03). In a cohort of HIV-infected adults, an increase in subgingival Porphyromonas gingivalis, a known periodontal pathogen, was significantly associated with longitudinal increases in IMT, while increased gingival recession, which herein may represent PD resolution, was significantly associated with longitudinal improvement in FMD. In the context of HIV infection, PD may contribute to CVD risk. Intervention studies treating PD may help clarify this association.

Periodontal disease, tooth loss and incident rheumatoid arthritis: results from the First National Health and Nutrition Examination Survey and its epidemiological follow-up study

AIMS

Infection may be a rheumatoid arthritis (RA) risk factor. We examined whether signs of periodontal infection were associated with RA development in the First National Health and Nutrition Examination Survey and its epidemiological follow-up study.

MATERIAL AND METHODS

In 1971-1974, 9702 men and women aged 25-74 were enrolled and surveyed longitudinally (1982, 1986, 1987, 1992). Periodontal infection was defined by baseline tooth loss or clinical evidence of periodontal disease. Baseline (n = 138) and incident (n = 433) RA cases were defined via self-report physician diagnosis, joint pain/swelling, ICD-9 codes (714.0-714.9), death certificates and/or RA hospitalization.

RESULTS

Adjusted odds ratios (ORs) (95% CI) for prevalent RA in gingivitis and periodontitis (versus healthy) were 1.09 (0.57, 2.10) and 1.85 (0.95, 3.63); incident RA ORs were 1.32 (0.85, 2.06) and 1.00 (0.68, 1.48). The ORs for prevalent RA among participants missing 5-8, 9-14, 15-31 or 32 teeth (versus 0-4 teeth) were 1.74 (1.03, 2.95), 1.82 (0.81, 4.10), 1.45 (0.62, 3.41) and 1.30 (0.48, 3.53); ORs for incident RA were 1.12 (0.77, 1.64), 1.67 (1.12, 2.48), 1.40 (0.85, 2.33) and 1.22 (0.75, 2.00). Dose-responsiveness was enhanced among never smokers. The rate of death or loss-to-follow-up after 1982 was two- to fourfold higher among participants with periodontitis or missing ≥9 teeth (versus healthy participants).

CONCLUSIONS

Although participants with periodontal disease or ≥5 missing teeth experienced higher odds of prevalent/incident RA, most ORs were non-statistically significant and lacked dose-responsiveness. Differential RA ascertainment bias complicated the interpretation of these data.

Subgingival microbial consortia and the clinical features of periodontitis in adolescents

This study aimed to investigate the association between microbial consortia and the clinical features of periodontitis using a multilevel modeling approach. A total of 958 sites in 87 adolescents with periodontitis (cases) and 73 controls were microbiologically sampled and clinically examined. Associations between each of the clinical parameters clinical attachment, probing depth, supragingival plaque, calculus, bleeding on probing, and each of 18 bacterial species; and between the same clinical parameters and each of two microbial consortia identified, were investigated using mixed-effects regression modeling. Higher counts of Tannerella forsythia, Campylobacter rectus, and Porphyromonas gingivalis were all statistically significantly associated with higher values of clinical attachment level, probing depth, and bleeding on probing in the sampled site, when both case status and between-subject variance were accounted for. Higher counts for the consortium comprising the putative periodontopathogens were statistically significantly associated in a dose-response manner with both higher clinical attachment levels and with increased pocket depth. The counts for the consortium predominantly comprising the early-colonizer species were statistically significantly negatively associated with the presence of supragingival calculus, but positively associated with the presence of supragingival plaque. The study demonstrates a relationship between the counts of putative periodontopathogens and clinical attachment levels and probing pocket depths, even for low levels of these clinical parameters.

Sex differences in destructive periodontal disease: a systematic review

BACKGROUND

Sexual dimorphisms exist in the prevalence and severity of many human conditions and diseases. Models of risk assessment for periodontitis, however, are inconsistent with respect to the inclusion of sex as a risk factor. A systematic review of the literature and meta-analyses estimates sex-related differences in the prevalence of periodontitis.

METHODS

MEDLINE, EMBASE, and SCOPUS databases were searched for population surveys (sample size >500, half-mouth minimum, clinical attachment level) containing prevalence data on destructive periodontal disease in males and females.

RESULTS

Data were stratified by disease thresholds (3, 4, 5, and 7 mm) representing 50,604 subjects from 12 population surveys meeting selection criteria. Using a ≥ 5-mm clinical attachment loss threshold, seven studies provided data, permitting computation of mean-weighted sex differences in prevalence. Four studies provided data enabling a meta-analysis of prevalence rates. Sex exhibited a significant association with prevalence, reflecting a 9% difference between males and females (37.4% versus 28.1%, respectively), although the overall effect of sex in the meta-analysis was comparatively small (d = 0.19; 95% confidence interval, 0.16 and 0.22). This mean difference in prevalence between males and females was similar regardless of severity of disease threshold and after adjustment for other risk factors.

CONCLUSIONS

Men appear at greater risk for destructive periodontal disease than women; however, men do not appear at higher risk for more rapid periodontal destruction than women.

"Gum bug, leave my heart alone!"--epidemiologic and mechanistic evidence linking periodontal infections and atherosclerosis

Evidence from epidemiologic studies suggests that periodontal infections are independently associated with subclinical and clinical atherosclerotic vascular disease. Although the strength of the reported associations is modest, the consistency of the data across diverse populations and a variety of exposure and outcome variables suggests that the findings are not spurious or attributable only to the effects of confounders. Analysis of limited data from interventional studies suggests that periodontal treatment generally results in favorable effects on subclinical markers of atherosclerosis, although such analysis also indicates considerable heterogeneity in responses. Experimental mechanistic in vitro and in vivo studies have established the plausibility of a link between periodontal infections and atherogenesis, and have identified biological pathways by which these effects may be mediated. However, the utilized models are mostly mono-infections of host cells by a limited number of 'model' periodontal pathogens, and therefore may not adequately portray human periodontitis as a polymicrobial, biofilm-mediated disease. Future research must identify in vivo pathways in humans that may (i) lead to periodontitis-induced atherogenesis, or (ii) result in treatment-induced reduction of atherosclerosis risk. Data from these studies will be essential for determining whether periodontal interventions have a role in the primary or secondary prevention of atherosclerosis.

Periodontal bacteria and hypertension: the oral infections and vascular disease epidemiology study (INVEST)

OBJECTIVE

Chronic infections, including periodontal infections, may predispose to cardiovascular disease. We investigated the relationship between periodontal microbiota and hypertension.

METHODS AND RESULTS

Six hundred and fifty-three dentate men and women with no history of stroke or myocardial infarction were enrolled in INVEST. We collected 4533 subgingival plaque samples (average of seven samples per participant). These were quantitatively assessed for 11 periodontal bacteria using DNA-DNA checkerboard hybridization. Cardiovascular risk factor measurements were obtained. Blood pressure and hypertension (SBP > or =140 mmHg, DBP > or =90 mmHg or taking antihypertensive medication, or self-reported history) were each regressed on the level of bacteria: considered causative of periodontal disease (etiologic bacterial burden); associated with periodontal disease (putative bacterial burden); and associated with periodontal health (health-associated bacterial burden). All analyses were adjusted for age, race/ethnicity, sex, education, BMI, smoking, diabetes, low-density lipoprotein and high-density lipoprotein cholesterol. Etiologic bacterial burden was positively associated with both blood pressure and prevalent hypertension. Comparing the highest and lowest tertiles of etiologic bacterial burden, SBP was 9 mmHg higher, DBP was 5 mmHg higher (P for linear trend was less than 0.001 in each case), and the odds ratio for prevalent hypertension was 3.05 (95% confidence interval 1.60-5.82) after multivariable adjustment.

CONCLUSION

Our data provide evidence of a direct relationship between the levels of subgingival periodontal bacteria and both SBP and DBP as well as hypertension prevalence.

Evaluating clinical periodontal measures as surrogates for bacterial exposure: the Oral Infections and Vascular Disease Epidemiology Study (INVEST)

Background

Epidemiologic studies of periodontal infection as a risk factor for cardiovascular disease often use clinical periodontal measures as a surrogate for the underlying bacterial exposure of interest. There are currently no methodological studies evaluating which clinical periodontal measures best reflect the levels of subgingival bacterial colonization in population-based settings. We investigated the characteristics of clinical periodontal definitions that were most representative of exposure to bacterial species that are believed to be either markers, or themselves etiologic, of periodontal disease.

Methods

706 men and women aged ≥ 55 years, residing in northern Manhattan were enrolled. Using DNA-DNA checkerboard hybridization in subgingival biofilms, standardized values for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia were averaged within mouth and summed to define "bacterial burden". Correlations of bacterial burden with clinical periodontal constructs defined by the severity and extent of attachment loss (AL), pocket depth (PD) and bleeding on probing (BOP) were assessed.

Results

Clinical periodontal constructs demonstrating the highest correlations with bacterial burden were: i) percent of sites with BOP (r = 0.62); ii) percent of sites with PD ≥ 3 mm (r = 0.61); and iii) number of sites with BOP (r = 0.59). Increasing PD or AL severity thresholds consistently attenuated correlations, i.e., the correlation of bacterial burden with the percent of sites with PD ≥ 8 mm was only r = 0.16.

Conclusions

Clinical exposure definitions of periodontal disease should incorporate relatively shallow pockets to best reflect whole mouth exposure to bacterial burden.