Association between severity of periodontitis and clinical activity in rheumatoid arthritis patients: a case-control study

Periodontitis and rheumatoid arthritis: What have we learned about their connection and their treatment?

Rheumatoid arthritis and periodontitis are chronic inflammatory diseases defined respectively by the destruction of the articular cartilage and tooth-supporting periodontal tissues. Although the epidemiologic evidence for an association between these two diseases is still scarce, there is emerging scientific information linking specific bacterial periodontal pathogens, such as Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, in the citrullination process, leading to autoantibody formation and compromised immunotolerance of the susceptible patient to rheumatoid arthritis. In this review, we update the existing information on the evidence, not only regarding the epidemiologic association, but also the biologic mechanisms linking these two diseases. Finally, we review information emerging from intervention studies evaluating whether periodontal treatment could influence the initiation and progression of rheumatoid arthritis.

Disease activity and subcutaneous nodules are associated to severe periodontitis in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) was significantly associated with increased overall risk of periodontitis, both chronic, inflammatory pathologies leading to connective tissue breakdown and bone destruction. To identify clinical and/or serological variables routinely evaluated during follow-up of people with RA which are associated with the severity of their periodontal disease. An observational, cross-sectional study was carried out, which included RA patients according to ACR/EULAR 2010 criteria having chronic periodontal disease. RA clinical parameters (disease duration, erythrocyte sedimentation rate, serum C-reactive protein, disease activity (DAS28) and rheumatoid factor, presence of bone erosions and rheumatic nodules) and also corticosteroid therapy were considered. Periodontitis was evaluated according to the American Academy of Periodontology (1999) and chronic periodontitis was assessed by full mouth periapical radiographic examination, periodontal probing depth, clinical attachment level and bleeding index. A total of 110 subjects with RA and chronic periodontitis were included. The female/male relation was 5.1, and no significant differences between genres were found in rheumatic or oral variables. RA patients with longer disease duration, higher disease activity and with rheumatic nodules had significantly greater periodontitis severity. Multivariate analysis confirmed that severe periodontitis was associated with DAS28³ 4.1 (OR 51.4, CI 95% 9.4-281.5) and the presence of rheumatic nodules (OR 6.4, CI 95% 1.3-31.6). Disease activity and rheumatic nodules were strongly associated with severe periodontitis. Based on these findings it would be desirable to include interdisciplinary management at an early stage of RA to ensure comprehensive treatment of both pathologies.

Porphyromonas gingivalis survival skills: Immune evasion

Periodontitis is a chronic inflammatory condition that destroys the tooth-supporting tissues and eventually leads to tooth loss. As one of the most prevalent oral conditions, periodontitis endangers the oral health of 70% of people throughout the world. Periodontitis is also related to various systemic diseases, such as diabetes mellitus, atherosclerosis, and rheumatoid arthritis, which not only has a great impact on population health status and the quality of life but also increases the social burden. Porphyromonas gingivalis (P. gingivalis) is a gram-negative oral anaerobic bacterium that plays a key role in the pathogenesis of periodontitis. Porphyromonas gingivalis can express various of virulence factors to overturn innate and adaptive immunities, which makes P. gingivalis survive and propagate in the host, destroy periodontal tissues, and have connection to systemic diseases. Porphyromonas gingivalis can invade into and survive in host tissues by destructing the gingival epithelial barrier, internalizing into the epithelial cells, and enhancing autophagy in epithelial cells. Deregulation of complement system, degradation of antibacterial peptides, and destruction of phagocyte functions facilitate the evasion of P. gingivalis. Porphyromonas gingivalis can also suppress adaptive immunity, which allows P. gingivalis to exist in the host tissues and cause the inflammatory response persistently. Here, we review studies devoted to understanding the strategies utilized by P. gingivalis to escape host immunity. Methods for impairing P. gingivalis immune evasion are also mentioned.

Effects of non-surgical periodontal therapy on periodontal clinical data in periodontitis patients with rheumatoid arthritis: a meta-analysis

Backgrounds

To date, there is still no consensus about the clinical efficacy of non-surgical periodontal therapy in rheumatoid arthritis (RA) patients with periodontitis. Therefore, the aim of this study was to summarize clinical data regarding the efficacy of scaling and root planing (SRP) in patients with RA and periodontitis compared to non-RA periodontitis patients.

Methods

We selected randomized controlled trials (RCTs) that compared periodontal clinical data in RA as compared to non-RA periodontitis patients by searching Embase, PubMed and Cochrane Central Register of Controlled Trials and by manually retrieving from the earliest records to March 8, 2021. The overall effect size of plaque index (PI), gingival index (GI), attachment loss (AL), probing depth (PD) and bleeding on probing (BOP) were calculated by either a fixed or random-effect model, and subgroup analyses were conducted according to the different time points of follow-up. Two investigators extracted the data and assess the accuracy of the obtained results with 95% of Confidence Intervals (CI). Cochrane Collaboration's tool was responsible for the evaluation of the literature quality and the inter-study heterogeneity was evaluated by Q test and I² statistic. Sensitivity analyses were applied for results with heterogeneity. Publication bias was determined by Begg's test, Egger's test and the trim-and-fill method.

Results

Seven RCTs including 212 patients eventually met the inclusion criteria for the study. As the primary results, the change of PD was not statistically significant and in the secondary results changes of PI, GI, AL and BOP were also not statistically significant in RA patients with periodontitis compared to non-RA periodontitis patients. In subgroup analysis, a larger BOP reduction at 3 months, PI and AL reduction at 6 months were observed in patients with RA and periodontitis group. The results of sensitivity analyses had no significant effect. No evidence of potential publication bias was tested. There were some limitations due to the small number of eligible RCTs.

Conclusions

SRP is equally effective in RA as compared to non-RA periodontitis patients. It suggests RA does not affect the clinical efficacy of non-surgical periodontal therapy. These results could serve evidence-based practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01695-w.

Tooth Loss Is Associated with Disease-Related Parameters in Patients with Rheumatoid Arthritis and Ankylosing Spondylitis-A Cross-Sectional Study

Background: The aim of this cross-sectional study was to investigate potential associations between periodontal inflamed surface area (PISA) and tooth loss with disease-related parameters in patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Methods: Patients who attended the Department of Nephrology and Rheumatology, University Medical Centre Goettingen, Germany, were included. The oral examination comprised the detection of the number of remaining teeth and periodontal condition based on staging and grading matrix. Based on periodontal pockets with positive bleeding on probing, the periodontal inflamed surface area (PISA) was determined. Disease related parameters were extracted from the patients’ records. Results: In total, 101 (RA) and 32 participants (AS) were included. Patients with RA had 22.85 ± 4.26 and AS patients 24.34 ± 5.47 remaining teeth (p < 0.01). Periodontitis stage III and IV was present in 91% (RA) and 81.2% (AS) of patients (p = 0.04). Associations between PISA and disease-related parameters were not found in both groups (p > 0.05). In RA, a higher age (p < 0.01), C-reactive protein (p = 0.02), disease activity (p < 0.01) and prednisolone intake (p < 0.01) were associated with fewer remaining teeth. In AS, a higher age (p = 0.02) and increased Bath Ankylosing Spondylitis Metrology Index (p = 0.02) were associated with a lower number of remaining teeth. Conclusions: Tooth loss is associated with disease activity, especially in RA individuals. Dental care to prevent tooth loss might be recommendable to positively influence oral health condition and disease activity in RA and SA patients.

Association between periodontitis and vitamin D status: A case-control study

Vitamin D deficiency and periodontitis are commonly prevalent among Saudi adults. However, the association between periodontitis and vitamin D status has not been well documented. This study aims to examine the association between periodontitis and vitamin D status among adults in the Albaha region of Saudi Arabia. A case-control study of 123 Saudi adults was conducted; 60 had severe or moderate periodontitis, and 63 were periodontally healthy. Data was collected by an online self-reported sociodemographic questionnaire. All participants then underwent a full periodontal examination. Blood samples were also provided to assess participants' vitamin D statuses through serum levels of 25-hydroxyvitamin D (25(OH)D). A total of 60 cases and 63 controls matched for BMI (30.2 ± 4.86 kg/m²), age (40.01 ± 7.73 years), and sex (46.3% and 53.7% male and female, respectively) participated in the study. Mean levels of 25(OH)D were significantly lower in periodontitis participants than in controls (25.03 ± 8.55 ng/ml, 29.19 ± 12.82 ng/ml, p = 0.037, respectively). Lower odds of periodontitis were detected per unit of 25(OH)D level (OR 0.964, 95% CI; 0.931-0.999, p = 0.043). In conclusion, periodontitis is significantly associated with deficient and insufficient levels of vitamin D among Saudi adults in the Albaha region. Future longitudinal research with a larger sample size may be suggested to confirm these results.

Rheumatoid arthritis serotype and synthetic disease-modifying anti-rheumatic drugs in patients with periodontitis: A case-control study

Patients with rheumatoid arthritis (RA) experience a higher prevalence of periodontitis. This study aimed to examine the variation of periodontitis experienced with different serotypes suffered by RA patients and to examine the relationship between the different medications taken for RA that may influence this relationship. Two hundred and sixty RA and control participants underwent standardized periodontal examinations. Medical, serological and radiological (Sharp/van der Heijde) records were assessed. Functional status was assessed using the administered Health Assessment Questionnaire. Moreover, disease parameters, including disease activity (DAS28-ESR) and anti-citrullinated protein antibodies (ACPA) and rheumatoid factor (RF) seropositivity were evaluated. Periodontitis was higher in RA (71.54%) compared with controls (54.62%). The stage of periodontitis experienced by ACPA-positive participants were higher than APCA-negative participants. The probing pocket depth and recession experienced by RF-positive participants were higher than those who were RF-negative. RA participants on methotrexate had lower clinical attachment loss and lower periodontal probing depth compared with participants on a combination methotrexate and other disease-modifying antirheumatic drugs. Participants taking corticosteroids had lower gingival index scores. The association between seropositivity and the type of medications taken with periodontal health parameters in this group of patients suggests that both seropositivity and medications taken are important modifiers in the relationship between periodontitis and RA.

Risk Factors for Developing Rheumatoid Arthritis in Patients With Undifferentiated Arthritis and Inflammatory Arthralgia

Currently, there is an increasing interest in treating patients at risk of rheumatoid arthritis (RA) to prevent the development of this chronic disease. In this sense, research has focused attention on the early identification of predictive factors of this disease. Autoantibodies and markers of systemic inflammation can be present before clinical arthritis and RA development. So, the phase of inflammatory arthralgia preceding clinical arthritis is an important part of the window of opportunity and, starting treatment might prevent progression to chronic arthritis. Additionally, the early diagnosis and treatment initiation, in patients with inflammatory arthritis at risk of persistence and/or erosive progression, are fundamental because may allow optimal clinical responses, better chances of achieving sustained remission, preventing irreversible organ damage and optimizing long-term outcomes. This review aims to give an overview of clinical risk factors for developing RA, both in suspected arthralgia and in undifferentiated arthritis. Besides taking into consideration the role of serological markers (immunological and acute phase reactants) and clinical features assessed at consultation such as: articular affection and patient's clinical perception. Other features as sociodemographic and environmental factors (lifestyle habits, microbiota, periodontal disease among others), have been included in this revision to give an insight on strategies to prevent development of RA and/or to treat it in early stages.

Anti-peptidylarginine deiminase-4 antibodies at mucosal sites can activate peptidylarginine deiminase-4 enzyme activity in rheumatoid arthritis

Background

Mucosal sites are hypothesized to play a role in the development of rheumatoid arthritis (RA). Since serum anti-peptidylarginine deiminase (PAD)4 antibodies, including a subset that cross-react with PAD3 (PAD3/4), are specific for RA and associate with severe disease, we sought to examine whether anti-PAD4 and anti-PAD3/4 antibodies were present in the lung and oral mucosa of subjects with RA and “at-risk” for RA.

Methods

We included 37 RA, 25 healthy control, and 46 subjects “at-risk” for RA based on familial RA and/or serum anti-citrullinated protein antibody (ACPA) positivity. Paired serum, sputum, and saliva were evaluated for anti-PAD4 and anti-PAD3/4 using immunoprecipitation and ACPA using ELISA. Immunoglobulins (Ig) were purified from representative samples, and their effect on citrullination of histone H3 by recombinant human PAD4 was measured by anti-citH3 immunoblot.

Results

Anti-PAD4 antibodies were detected in the serum of 6/37 (16.2%), sputum of 3/37 (8.1%), and saliva of 3/33 (9.1%) RA subjects and in the serum and sputum of 1/46 (2.2%) at-risk subjects. None of the healthy controls had anti-PAD4 antibodies at any site. Serum, sputum, and salivary anti-PAD4 antibodies were more prevalent in RA subjects with RA duration >2 years. Purified antibodies from representative anti-PAD4-positive and anti-PAD3/4-positive sputum were primarily of the IgA isotype and able to increase PAD4 enzymatic activity.

Conclusions

Anti-PAD4 antibodies are present in the sputum and saliva of a portion of RA patients and are infrequent in at-risk subjects. Importantly, the ability of anti-PAD4, and particularly anti-PAD3/4, antibodies in the sputum to enhance PAD4 enzymatic activity suggests that anti-PAD4 may play an active role in the RA lung.

Periodontal disease in seropositive rheumatoid arthritis: scoping review of the epidemiological evidence

The link between periodontal disease (PD) and rheumatoid arthritis (RA) has been hypothesized to lie in the anti-cyclic citrullinated protein antibody (ACPA) molecules present in seropositive RA. This review aimed to discuss how RA and specifically ACPA-positive RA link to PD, and appraise the epidemiological evidence on the relationship between ACPA-positive RA and PD. Articles were searched following the PRISMA guideline across the MEDLINE, Web of Science, Scopus and Cochrane Library databases. A total of 21 articles met the inclusion criteria of reporting the epidemiological data on the different ACPA status of the subjects with RA and PD (or periodontitis) parameters. A discrepancy is noted in the epidemiological evidence on the difference in the prevalence and severity of PD between ACPA-positive and ACPA-negative RA patients. Although the link between RA and PD is mostly discussed in terms of ACPA, reports on the different manifestations of PD between the two RA subsets remains inconclusive.

Oral Health in Rheumatoid Arthritis: Listening to Patients

INTRODUCTION

Rates of periodontal disease and tooth loss are increased in individuals with rheumatoid arthritis (RA). Understanding factors that contribute to the increased burden of periodontal disease in RA is critical to improving oral health and arthritis outcomes.

OBJECTIVES

To determine the perceptions held by people with RA relating to their oral health, to identify patient-centered priorities for oral health research, and to inform optimal strategies for delivering oral health knowledge.

METHODS

Semistructured interviews were conducted with patients with RA. Recorded interview transcripts were iteratively reviewed to reveal surface and latent meaning and to code for themes. Constructs were considered saturated when no new themes were identified in subsequent interviews. We report themes with representative quotes.

RESULTS

Interviews were conducted with 11 individuals with RA (10 women [91%]; mean age, 68 y), all of whom were taking RA medication. Interviews averaged 19 min (range, 8 to 31 min) and were mostly conducted face-to-face. Three overall themes were identified: 1) knowledge about arthritis and oral health links; 2) oral health care in RA is complicated, both in personal hygiene practices and in professional oral care; and 3) poor oral health is a source of shame. Participants preferred to receive oral health education from their rheumatologists or dentists.

CONCLUSIONS

People with RA have unique oral health perceptions and experience significant challenges with oral health care due to their arthritis. Adapting oral hygiene recommendations and professional oral care delivery to the needs of those with arthritis are patient priorities and are required to improve satisfaction regarding their oral health.

KNOWLEDGE TRANSLATION STATEMENT

Patients living with long-standing rheumatoid arthritis described poor oral health-related quality of life and multiple challenges with maintaining optimal oral health. Study findings indicate a need for educational materials addressing oral health maintenance for patients with rheumatic diseases and their providers.

Periodontitis as a risk factor for rheumatoid arthritis: a matched-cohort study

OBJECTIVE

The intent was to analyse the association of periodontitis with the development of rheumatoid arthritis (RA) using a representative population-based cohort and longitudinal matched-cohort design.

METHODS

Participants were 40 years of age or older and had not been diagnosed with RA between 2002 and 2006. Among the participants, those who were newly diagnosed with periodontitis between 2004 and 2006 (excluding cases that had already been diagnosed with periodontitis between 2002 and 2003) were allotted to the periodontitis group. Among the participants, those who had never been diagnosed with periodontitis between 2002 and 2006 formed the control group, matched by sex, age, and household income at a 1:1 ratio. From 2007 to 2018, the 2 groups (n = 691,506) were followed to monitor the development of RA. The t-test and χ² test compared the general characteristics and health-related variables of both groups. The Kaplan-Meier method with a log-rank test was conducted to compare the incidence of RA in both groups. The hazard ratio (HR) and adjusted hazard ratio (aHR) were calculated using a Cox proportional hazard regression analysis to evaluate the risk of subsequent RA.

RESULTS

Univariate analysis revealed that the periodontitis group was more likely to develop RA than the control group (hazard ratio 1.10), and multivariate analysis also revealed a higher incidence risk of RA (adjusted hazard ratio 1.09) in the periodontitis group.

CONCLUSIONS

Our findings demonstrate that periodontitis is associated with an increased risk of developing RA.

Association among periodontitis severity, anti-agalactosyl immunoglobulin G titer, and the disease activity of rheumatoid arthritis

OBJECTIVE

The aim of the present study was to evaluate the association between the periodontal and serological parameters and the disease activity of rheumatoid arthritis (RA) and between the anti-agalactosyl immunoglobulin G (IgG) titer and periodontitis severity. The objective was also to assess the effect of supragingival scaling on the serological parameters in patients with RA.

BACKGROUND

The periodontal and serological parameters in relation to the autoimmune inflammatory response have been linked to RA disease activity. However, the association of the anti-agalactosyl IgG titer with RA disease activity and periodontitis severity has not been elucidated.

METHODS

The periodontal, rheumatologic, and serological data were collected from 127 patients with RA in a retrospective cohort study. Of the 127 patients, 21 had been randomly assigned to receive oral hygiene instruction and supragingival scaling. The anti-agalactosyl IgG titer was determined by an electrochemiluminescence immunoassay.

RESULTS

The patients with a moderate to high RA disease activity showed significantly higher levels of probing depth (PD), clinical attachment level, anti-cyclic citrullinated peptide IgG, and anti-agalactosyl IgG titer and greater mean percentages of severe periodontitis than those with a low RA disease activity (p < .05 for all). Both univariate and multivariate analyses revealed a significantly positive correlation between the PD and RA disease activity (p = .009 and p = .001), between the anti-agalactosyl IgG titer and RA disease activity (p = .002 and p < .001), and between the anti-agalactosyl IgG titer and PD (p < .001 for both). Supragingival scaling significantly decreased the anti-agalactosyl IgG titer (p = 0.03).

CONCLUSION

The PD and anti-agalactosyl IgG titer are positively interrelated, both of which are correlated positively with RA disease activity and influenced by supragingival scaling in patients with RA.

Investigating the relationship between the severity of periodontitis and rheumatoid arthritis: a cross-sectional study

OBJECTIVES

This paper evaluates the prevalence and severity of periodontitis (PD) in patients with rheumatoid arthritis (RA), focusing on the link between the severity of PD with RA disease activity/disability scores, the influence of RA treatment on PD, and levels of vitamin D.

METHODS

A total of 93 RA patients were enrolled in the cross-sectional study and analyzed accordingly as RA-PD (N = 63, 67.8%) and RA-only (N = 30, 32.2%) groups. A number of associations between rheumatological clinical data, i.e., Disease Activity Score (DAS28 CRP), health assessment questionnaires, and PD severity (measured by periodontal outcome parameters) with regard to serum levels of vitamin D were assessed. The outcome variables were compared by parametric and non-parametric tests.

RESULTS

A total of 29% of RA patients were diagnosed with severe PD. The RA-PD group presented a higher mean DAS28 CRP score in moderate-severe PD compared to periodontally healthy-initial stage PD subjects (4.49 ± 1.22 vs. 3.86 ± 1.58, p = 0.033). RA patients treated with biologic disease-modifying antirheumatic drugs (bDMARDs) were less likely to be diagnosed with PD (p = 0.022) and revealed significantly lower PD outcome parameters, i.e., bleeding on probing (%) and bone loss (%) (p < 0.05). Vitamin D concentration was significantly lower in RA-PD group with diagnosed advanced severe PD (IV stage) compared to moderate PD (II stage) (39.61 ± 17.12 vs. 52.07 ± 18.23 nmol/l, p = 0.031).

CONCLUSIONS

The study revealed a high prevalence of severe PD in RA patients, being significantly associated with higher RA disease activity and lower vitamin D level in RA-PD group, while bDMARD treatment was related to lower PD outcome parameters. Key Points • Severe PD is prevalent amongst RA patients and is associated with RA disease activity. The higher RA DAS28 CRP score is associated with moderate-severe PD compared to periodontally healthy-initial stage PD in RA patients. • Biologic DMARDs treatment used for RA is linked to lower PD rates and PD outcome parameters. • Significantly lower vitamin D level is found in advanced severe PD compared to moderate PD stage in RA-PD subjects.

Local and systemic mechanisms linking periodontal disease and inflammatory comorbidities

Periodontitis, a major inflammatory disease of the oral mucosa, is epidemiologically associated with other chronic inflammation-driven disorders, including cardio-metabolic, neurodegenerative and autoimmune diseases and cancer. Emerging evidence from interventional studies indicates that local treatment of periodontitis ameliorates surrogate markers of comorbid conditions. The potential causal link between periodontitis and its comorbidities is further strengthened by recent experimental animal studies establishing biologically plausible and clinically consistent mechanisms whereby periodontitis could initiate or aggravate a comorbid condition. This multi-faceted ‘mechanistic causality’ aspect of the link between periodontitis and comorbidities is the focus of this Review. Understanding how certain extra-oral pathologies are affected by disseminated periodontal pathogens and periodontitis-associated systemic inflammation, including adaptation of bone marrow haematopoietic progenitors, may provide new therapeutic options to reduce the risk of periodontitis-associated comorbidities.

Periodontitis has been causally linked to the development of other chronic inflammatory diseases outside the oral mucosa. In this Review, George Hajishengallis and Triantafyllos Chavakis consider the molecular basis of these links.

Associations of periodontal status in periodontitis and rheumatoid arthritis patients

Purpose

The aim of this study was to assess the association between the clinical status of rheumatoid arthritis (RA) and periodontitis (PD) in patients diagnosed with PD and to evaluate the impact of RA treatment on the severity of PD.

Methods

The study included 148 participants with PD, of whom 64 were also diagnosed with RA (PD+RA group), while 84 age-matched participants were rheumatologically healthy (PD-only group). PD severity was assessed by the following periodontal parameters: clinical attachment loss, probing pocket depth (PPD), bleeding on probing (BOP), alveolar bone loss, and number of missing teeth. RA disease characteristics and impact of disease were evaluated by the Disease Activity Score 28 using C-reactive protein, disease duration, RA treatment, the RA Impact of Disease tool, and the Health Assessment Questionnaire. Outcome variables were compared using parametric and non-parametric tests and associations were evaluated using regression analysis with the calculation of odds ratios (ORs).

Results

Participants in the PD+RA group had higher mean PPD values (2.81 ± 0.59 mm vs. 2.58 ± 0.49 mm, P=0.009) and number of missing teeth (6.27±4.79 vs. 3.93±4.08, P=0.001) than those in the PD-only group. A significant association was found between mean PPD and RA (OR, 2.22; 95% CI, 1.16–4.31; P=0.016). Within the PD+RA group, moderate to severe periodontal disease was significantly more prevalent among participants with higher RA disease activity (P=0.042). The use of biologic disease-modifying antirheumatic drugs (bDMARDs) was associated with a lower BOP percentage (P=0.016).

Conclusions

In patients with PD, RA was associated with a higher mean PPD and number of missing teeth. The severity of PD was affected by the RA disease clinical activity and by treatment with bDMARDs, which were associated with a significantly lower mean BOP percentage.

Impact of systemic factors in shaping the periodontal microbiome

Since 2010, next-generation sequencing platforms have laid the foundation to an exciting phase of discovery in oral microbiology as it relates to oral and systemic health and disease. Next-generation sequencing has allowed large-scale oral microbial surveys, based on informative marker genes, such as 16S ribosomal RNA, community gene inventories (metagenomics), and functional analyses (metatranscriptomics), to be undertaken. More specifically, the availability of next-generation sequencing has also paved the way for studying, in greater depth and breadth, the effect of systemic factors on the periodontal microbiome. It was natural to investigate systemic diseases, such as diabetes, in such studies, along with systemic conditions or states, , pregnancy, menopause, stress, rheumatoid arthritis, and systemic lupus erythematosus. In addition, in recent years, the relevance of systemic "variables" (ie, factors that are not necessarily diseases or conditions, but may modulate the periodontal microbiome) has been explored in detail. These include ethnicity and genetics. In the present manuscript, we describe and elaborate on the new and confirmatory findings unveiled by next-generation sequencing as it pertains to systemic factors that may shape the periodontal microbiome. We also explore the systemic and mechanistic basis for such modulation and highlight the importance of those relationships in the management and treatment of patients.

Does Nonsurgical Periodontal Treatment Improve Systemic Health?

Clinicians frequently stress the importance of maintaining good oral health for multiple reasons, including its link to systemic health. Because periodontal treatment reduces inflammation in oral tissues, some hypothesize it may positively affect systemic outcomes by reducing inflammation in the body. A significant number of systematic reviews (SRs) and meta-analyses (MAs) have evaluated the effect of periodontal treatment on systemic outcomes. However, inconsistent findings and questionable methodological rigor make drawing conclusions difficult. We conducted a systematic review of reviews that studied the effect of nonsurgical periodontal treatment on systemic disease outcomes. We report on outcomes evaluated, categorizing them as biomarkers, and surrogate or clinical endpoints. In addition, we used A MeaSurement Tool to Access systematic Reviews 2 (AMSTAR 2) to evaluate the methodological quality of the reviews. Of the 52 studies included in our review, 21 focused on diabetes, 15 on adverse birth outcomes, 8 on cardiovascular disease, 3 each on obesity and rheumatoid arthritis, and 2 on chronic kidney disease. Across all studies, surrogate endpoints predominated as outcomes, followed by biomarkers and, rarely, actual disease endpoints. Ninety-two percent of studies had "low" or "critically low" AMSTAR 2 confidence ratings. Criteria not met most frequently included advance registration of the protocol, justification for excluding individual studies, risk of bias from individual studies being included in the review, and appropriateness of meta-analytical methods. There is a dearth of robust evidence on whether nonsurgical periodontal treatment improves systemic disease outcomes. Future reviews should adhere more closely to methodological guidelines for conducting and reporting SRs/MAs than has been the case to date. Beyond improved reviews, additional rigorous research on whether periodontal treatment affects systemic health is needed. We highlight the potential of large-scale databases containing matched medical and dental record data to inform and complement future clinical research studying the effect of periodontal treatment on systemic outcomes.

rs2476601 in PTPN22 gene in rheumatoid arthritis and periodontitis-a possible interface?

BACKGROUND

Rheumatoid arthritis (RA) and periodontitis (PD) are proven to share common risk markers, including genetic factors. In the present study we focused on genetic variants in PTPN22 (rs2476601), PADI4 (rs2240340), CTLA4 genes (rs3087243) and its impact on RA and PD.

MATERIALS AND METHODS

In the study 111 RA patients and 256 systemically healthy controls were involved. A subdivision of patients and controls was carried out according the severity of periodontitis (no/level 1 PD vs. level 2 PD).

RESULTS

I. Evaluating the genetic impact on the occurrence of RA the T allele of rs2476601 (PTPN22) (bivariate: p < 0.001; multivariate: p = 0.018) and T allele of rs2240340 (PADI4) (bivariate: p = 0.006; multivariate: p = 0.070) were associated with an increased vulnerability to RA. II. Investigating the genetic influence on level 2 PD the T allele of rs2476601 (PTPN22) was shown to be associated with a higher susceptibility to PD within the RA group (bivariate: p = 0.043; multivariate: p = 0.024). III. The T allele of rs2476601 (PTPN22) was proven to be a significant marker of RA and level 2 PD comorbidity (bivariate: p < 0.001; multivariate: p = 0.028).

CONCLUSIONS

These results support the thesis that genetic variations may represent a possible link between PD and RA. The study increases knowledge about disease-specific and cross-disease genetic pattern.

Relationship between periodontitis and rheumatoid arthritis in Vietnamese patients

Objective: This study aimed to survey periodontal status of Vietnamese patients with rheumatoid arthritis (RA) and investigates the association between periodontitis and RA in these patients.Materials and methods: We conducted a cross-sectional descriptive study on 150 RA patients and another 150 patients with osteoarthritis (OA). RA was evaluated using the DAS28 disease activity score based on C-reactive protein levels (DAS28-CRP), disease activity classification, and serum levels of RA biomarkers. Periodontal status was determined using periodontal indices.Results: The proportion of periodontitis cases in the RA group was significantly higher than the OA group (67 and 28%, respectively). The rate of severe periodontitis observed in the RA group was also significantly higher than that in the OA group (22.7 and 8%, respectively). RA patients with periodontitis had higher DAS28-CRP scores, disease activity levels, ACPA positivity and higher serum levels of CRP and ACPAs. Periodontitis is associated with an increased risk for RA (odds ratio [OR]: 5.14, 95% confidence interval [CI]: 3.14 - 8.41) and with higher disease activity classification (OR: 2.7, 95% CI: 1.14 - 6.42).Conclusions: Vietnamese RA patients often presented with a more serious periodontal condition than OA patients. We observed an association between periodontal disease (PD) status and clinic symptoms and biochemical/immunological characteristics of RA.

Does periodontitis affect the treatment response of biologics in the treatment of rheumatoid arthritis?

BACKGROUND

Rheumatoid arthritis (RA) and periodontitis (PD) have been suggested to share many clinical and pathological features. However, few reports have investigated the relationship between the degree of PD and the treatment response to RA. This study aimed to examine the relationship between the extent of PD and the treatment response to biologics in RA patients using FDG-PET/CT.

METHODS

Sixty RA patients (male, n = 14; female, n = 46; average age, 58.3 years) treated with biologic agents were included in this study. FDG-PET/CT was performed at baseline and 6 months after the initiation of biological therapy. The maximum standardized uptake value (SUVmax) was used as a representative value for the assessment of the FDG uptake in periodontal tissue and joints including the bilateral shoulders, elbows, wrists, hip, knees, and ankle joints. The Disease Activity Score (DAS) 28-CRP and the following clinical parameters were assessed: C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), anti-cyclic citrullinated peptide antibody (ACPA), rheumatoid factor (RF), and matrix metalloproteinase 3 (MMP-3). The relationship between the treatment response of RA and the baseline SUVmax of the periodontal tissue was evaluated.

RESULTS

The baseline periodontal SUVmax was related to patient age (r = 0.302, p = 0.009) and the ACPA level (r = 0.265, p = 0.025). The DAS28-CRP, CRP, ESR, MMP-3, and joint SUVmax values were significantly decreased after 6 months of biological therapy. However, the mean periodontal SUVmax, ACPA, and RF showed no significant changes after treatment. There was a significantly negative correlation between the baseline periodontal SUVmax and the treatment response of DAS28-CRP (r = - 0.369, p = 0.004).

CONCLUSION

There was a negative correlation between the extent of PD at baseline and the treatment response of RA patients who received biological therapy. The evaluation of the periodontal condition is considered to be an essential part for the management of RA.

The association between rheumatoid arthritis and periodontal disease in a population-based cross-sectional case-control study

Background

The association between rheumatoid arthritis (RA) and periodontitis remains unclear.

Methods

We studied oral health and periodontitis in a population-based case-control study of individuals with ≥10 remaining teeth ≥61 years of age and either with, or without a diagnosis of RA. 126 dentate individuals with RA were recruited together with age-matched control individuals without RA. The control individuals were recruited from the general population from the same city (n = 249). A dental examination including a panoramic radiograph was performed on all participants. All individuals with RA were examined and medical records were reviewed by a rheumatologist. In the control group, none of the participants presented with symptoms of RA and their medical records were also negative.

Results

The RA group included more women (66.7% vs. 55.8%) (p < 0.01). Individuals in the RA group had a higher body mass index (BMI) (p < 0.001). A diagnosis of periodontitis was more common in the RA group (61.1%) than in the control group (33.7%) (p = 0.001). Binary logistic regression analysis identified that a BMI > 25 (OR 6.2, 95% CI 3.6, 10.5, p = 0.000), periodontitis (OR 2.5 95% CI 1.5, 4.2 p = 0.000), and female gender (OR 2.3, 95% CI 1.3–4.0, p = 0.003) were associated with RA.

Conclusion

RA was associated a diagnosis of periodontitis.

Considerations for improving quality of care of patients with rheumatoid arthritis and associated comorbidities

OBJECTIVE

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disorder with a global prevalence of approximately 0.5-1%. Patients with RA are at an increased risk of developing comorbidities (eg, cardiovascular disease, pulmonary disease, diabetes and depression). Despite this, there are limited recommendations for the management and implementation of associated comorbidities. This study aimed to identify good practice interventions in the care of RA and associated comorbidities.

METHODS

A combination of primary research (180+ interviews with specialists across 12 European rheumatology centres) and secondary research (literature review of existing publications and guidelines/recommendations) were used to identify challenges in management and corresponding good practice interventions. Findings were prioritised and reviewed by a group of 18 rheumatology experts including rheumatologists, comorbidity experts, a patient representative and a highly specialised nurse.

RESULTS

Challenges throughout the patient pathway (including delays in diagnosis and referral, shortage of rheumatologists, limited awareness of primary care professionals) and 18 good practice interventions were identified in the study. The expert group segmented and prioritised interventions according to three distinct stages of the disease: (1) suspected RA, (2) recent diagnosis of RA and (3) established RA. Examples of good practice interventions included enabling self-management (self-monitoring and disease management support, for example, lifestyle adaptations); early arthritis clinic; rapid access to care (online referral, triage, ultrasound-guided diagnosis); dedicated comorbidity specialists; enhanced communication with primary care (hotline, education sessions); and integrating patient registries into daily clinical practice.

CONCLUSION

Learning from implementation of good practice interventions in centres across Europe provides an opportunity to more widely improved care for patients with RA and associated comorbidities.

Prevalence and severity of periodontitis in patients with established rheumatoid arthritis and osteoarthritis

Introduction

Periodontitis is associated with many chronic health conditions including diabetes, cardiovascular disease, and rheumatoid arthritis (RA). RA and periodontitis have similarities in inflammatory mechanism, morphology, and histopathology. Osteoarthritis (OA) is a chronic, multifactorial degenerative disease characterized by the deterioration of cartilage in joints.

Objective

The aim of this study was to evaluate the prevalence and severity of periodontal disease in patients with established RA and OA.

Materials and Methods

A total of 200 patients reporting to the Department of Orthopaedics, KIMSDU, Karad were included in the study. Patients were divided into two groups: Group 1 that included 100 patients with established RA diagnosed according to American College of Rheumatology (ACR) classification 1987 criteria and Group 2 that comprised 100 patients diagnosed with OA. Demographic profile, medical and dental history, oral hygiene practices, and smoking status of study participants were recorded. Periodontal status of the patients were evaluated using the simplified oral hygiene index (OHI-S), Loe and Silness gingival index (GI), probing pocket depth (PPD), and clinical attachment level (CAL). On the basis of the CAL score periodontitis severity was defined as slight, moderate, and severe. Rheumatoid Factor (RF) and C-reactive protein (CRP) were considered as a serological marker in RA. Serological tests were performed to measure RF and CRP. Periodontal parameters and serological tests were correlated.

Results

This study reported 45% severe periodontitis prevalence in RA compared to OA group, which was 33%. Severity of periodontitis is significantly greater in RF positive RA group with mean CAL 5.38 mm compared to RF negative RA group with mean CAL 2.81 mm (P = 0.001). There was moderate positive correlation found between RF titer and severity of periodontitis (r = 0.311).

Conclusion

The severity of periodontitis was significantly higher among the patients with established RA as compared to patients with OA. RF positive patients had higher periodontal disease compared to RF negative patients. There was an increase in the mean clinical attachment loss with increase in RF titer.

Upregulation of circulating inflammatory biomarkers under the influence of periodontal disease in rheumatoid arthritis patients

OBJECTIVES

Periodontal disease (PD) and rheumatoid arthritis (RA) are chronic immuno-inflammatory conditions with osteolysis being a hallmark feature. The influence of PD on RA's systemic inflammatory status and disease activity remains unclear. The objective of this study was to assess the systemic inflammation and disease activity of RA under the influence of PD.

METHODS

In this case-control study, 38 RA patients (19 with PD and 19 without PD) were compared to 38 non-RA patients and 12 healthy controls. Periodontal parameters (bleeding on probing (BOP), probing pocket depth (PPD), PPD Total, PPD Disease and marginal bone loss (MBL) were determined. Serological analyses included quantification of 92 inflammatory biomarkers using a multiplex proximity extension assay, anti-citrullinated protein antibodies (ACPA), rheumatoid factor (IgM-RF) and erythrocyte sedimentation rate (ESR). RA disease activity was determined using Disease Activity Score for 28 joints (DAS28). All RA patients were on medication.

RESULTS

IgM-RF was higher in RA patients with PD. PD conditions were more severe in the non-RA group. Inflammatory biomarkers (IL-10RB, IL-18, CSF-1, NT-3, TRAIL, PD-L1, LIF-R, SLAMF1, FGF-19, TRANCE, CST5, STAMPB, SIRT2, TWEAK, CX3CL1, CXCL5, MCP-1) were significantly higher in RA patients with PD than RA without PD. DAS28 associated with twice as many inflammatory biomarkers in RA patients with PD whereas IgM-RF and ACPA associated more frequently with biomarkers in the RA without PD group. IgM-RF correlated inversely with BOP.

CONCLUSION

Periodontal disease augments systemic inflammation in RA. A profound influence exists independent of autoimmune status.

Association between periodontitis and anti-citrullinated protein antibodies in rheumatoid arthritis patients: a cross-sectional study

AIM

The aim of this study was to evaluate the association between periodontal parameters related with the periodontal disease severity and the presence and levels of anti-citrullinated protein antibodies (ACPAs) in rheumatoid arthritis (RA) patients.

MATERIALS AND METHODS

This cross-sectional study included 164 RA patients. Socio-demographics and RA disease characteristics, including ELISA-detected ACPA (anti-CCP-2), were recorded. Exposure was assessed by periodontal parameters: plaque index (PI), bleeding on probing (BoP), probing pocket depth, and clinical attachment levels (CAL). Presence and levels of ACPAs (outcome) and exposure variables were compared by both parametric and non-parametric tests and associations were evaluated by adjusted odds ratio (OR).

RESULTS

A significant association was observed between the presence of anti-CCP antibodies and severity of periodontal outcomes such as the mean CAL (OR 1.483, p = 0.036), mean PI (OR 1.029, p = 0.012), and the number of pockets ≥ 5 mm (OR 1.021, p = 0.08). High anti-CCP antibodies levels were associated with mean CAL, mean PI, and number of pockets ≥ 5 mm with an OR of 1.593 (p = 0.043), 1.060 (p <  0.001), and 1.031 (p = 0.031), respectively. Furthermore, a significant increase of 4.45 U/mL in anti-CCP antibodies levels (p = 0.002) in RA patients was found for each pocket ≥ 5 mm after adjusting for age, gender, smoking, time of disease evolution, and RA activity.

CONCLUSIONS

In RA patients, the severity of periodontal conditions such as mean CAL, mean PI, and the number of pockets ≥ 5 mm were linearly associated with both the presence and levels of anti-CCP antibodies.

Experimental arthritis and Porphyromonas gingivalis administration synergistically decrease bone regeneration in femoral cortical defects

Porphyromonas gingivalis infection can lead to periodontitis and dysbiosis, which are known risk factors for rheumatoid arthritis (RA). We investigated whether P. gingivalis administration affected bone regeneration in mice with or without arthritis. We administered P. gingivalis to male DBA/1 J mice that were or were not sensitised to type II collagen-induced arthritis (CIA). All mice underwent drilling of bilateral femurs. We histologically evaluated new bone regeneration (bone volume of the defect [BVd]/tissue volume of the defect [TVd]) using micro-computed tomography (micro-CT), osteoclast number/bone area, and active osteoblast surface/bone surface (Ob.S/BS). We measured serum cytokine levels and bone mineral density of the proximal tibia using micro-CT. CIA resulted in significantly reduced bone regeneration (BVd/TVd) at all time-points, whereas P. gingivalis administration showed similar effects at 2 weeks postoperatively. CIA resulted in higher osteoclast number/bone area and lower Ob.S/BS at 2 and 3 weeks postoperatively, respectively. However, P. gingivalis administration resulted in lower Ob.S/BS only at 2 weeks postoperatively. During later-stage bone regeneration, CIA and P. gingivalis administration synergistically decreased BVd/TVd, increased serum tumour necrosis factor-α, and resulted in the lowest bone mineral density. Therefore, RA and dysbiosis could be risk factors for prolonged fracture healing.

Identification of a Kavain Analog with Efficient Anti-inflammatory Effects

Kavain, a compound derived from Piper methysticum, has demonstrated anti-inflammatory properties. To optimize its drug properties, identification and development of new kavain-derived compounds was undertaken. A focused library of analogs was synthesized and their effects on Porphyromonas gingivalis (P. gingivalis) elicited inflammation were evaluated in vitro and in vivo. The library contained cyclohexenones (5,5-dimethyl substituted cyclohexenones) substituted with a benzoate derivative at the 3-position of the cyclohexanone. The most promising analog identifed was a methylated derivative of kavain, Kava-205Me (5,5-dimethyl-3-oxocyclohex-1-en-1-yl 4-methylbenzoate.) In an in vitro assay of anti-inflammatory effects, murine macrophages (BMM) and THP-1 cells were infected with P. gingivalis (MOI = 20:1) and a panel of cytokines were measured. Both cell types treated with Kava-205Me (10 to 200 μg/ml) showed significantly and dose-dependently reduced TNF-α secretion induced by P. gingivalis. In BMM, Kava-205Me also reduced secretion of other cytokines involved in the early phase of inflammation, including IL-12, eotaxin, RANTES, IL-10 and interferon-γ (p < 0.05). In vivo, in an acute model of P. gingivalis-induced calvarial destruction, administration of Kava-205Me significantly improved the rate of healing associated with reduced soft tissue inflammation and osteoclast activation. In an infective arthritis murine model induced by injection of collagen-antibody (ArthriomAb) + P. gingivalis, administration of Kava-205Me was able to reduce efficiently paw swelling and joint destruction. These results highlight the strong anti-inflammatory properties of Kava-205Me and strengthen the interest of testing such compounds in the management of P. gingivalis elicited inflammation, especially in the management of periodontitis.

Periodontal disease in Chinese patients with rheumatoid arthritis: A case-control study

OBJECTIVE

To evaluate the prevalence and severity of periodontal disease in Chinese rheumatoid arthritis patients.

SUBJECTS AND METHODS

This cross-sectional study included 128 RA and 109 healthy controls. Two dentists conducted periodontal status including Plaque index (PI), Gingival index (GI), pocket probing depths (PPDs), Clinical attachment level (CAL) and Bleeding on probing (BOP) independently. Sociodemographic, lifestyle, clinical parameters and use of medication were assessed. Data were analyzed by Student's t test, χ² test, Wilcoxin-Mann- Whitney's test, Correlational Analysis, univariate or multivariate logistic regression.

RESULTS

The periodontal status was significantly worse in RA, especially the condition of dental and gingival status. RA had 4.68-fold. After adjusted potential risk factors, RA had 10.26-fold. The independent variable related to GI was DAS28 (p = .05) negatively, to the contrary, ESR (p = .013) was positively associated; the independent variable positively and related to periodontitis was educational level (p = .021) and anti-CCP positivity (p = .002). Through multivariate logistic regression, age and swollen joint were the independent variable related to periodontitis of RA (OR 1.087, p = .044) and (OR 1.560, p = .008) respectively.

CONCLUSIONS

Chinese RA patients show higher odds of PD. It is important to take early interventions in combination with medical therapy.

Prevalence of Periodontal Disease and Periodontopathic Bacteria in Anti-Cyclic Citrullinated Protein Antibody-Positive At-Risk Adults Without Arthritis

IMPORTANCE

The prevalence of periodontitis is increased in patients with rheumatoid arthritis (RA) and periodontopathic bacteria can citrullinate proteins. Periodontitis may, therefore, be an initiator of RA and a target for prevention. Periodontal disease and periodontal bacteria have not been investigated in at-risk individuals with RA autoimmunity but no arthritis.

OBJECTIVE

To examine periodontal disease and periodontopathic bacteria in anti-cyclic citrullinated protein (anti-CCP) antibody-positive at-risk individuals without arthritis.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study took place at a teaching hospital from April 27, 2015, to May 8, 2017. Forty-eight anti-CCP-positive individuals without arthritis (CCP+ at-risk) were recruited nationally. Twenty-six patients with early RA (ERA) and 32 healthy control individuals were recruited locally. Data were analyzed between June 1, 2017, and December 1, 2017.

INTERVENTIONS

Periodontal assessment and examination of joints using ultrasonography.

MAIN OUTCOMES AND MEASURES

Prevalence of diseased periodontal sites, clinical periodontitis, and periodontal inflamed surface area in CCP+ at-risk individuals compared with patients with ERA and healthy individuals matched for age and smoking. Paired-end sequencing of DNA from subgingival plaque from diseased and healthy periodontal sites was performed and DNA was profiled and analyzed.

RESULTS

A total of 48 CCP+ at-risk individuals (mean [SD] age, 51.9 [11.4] years; 31 [65%] female), 26 patients with ERA (mean [SD] age, 54.4 [16.7] years; 14 [54%] female), and 32 healthy individuals (mean [SD] age, 49.4 [15.3] years; 19 [59%] female) were recruited. Of 48 CCP+ at-risk individuals, 46 had no joint inflammation on ultrasonography. Thirty-five CCP+ at-risk individuals (73%), 12 healthy individuals (38%), and 14 patients with ERA (54%) had clinical periodontitis. The median (interquartile range) percentage of periodontal sites with disease was greater in CCP+ at-risk individuals compared with healthy individuals (3.3% [0%-11.3%] vs 0% [0%-0.7%]) and similar to patients with ERA (1.1% [0%-13.1%]). Median (interquartile range) periodontal inflamed surface area was higher in CCP+ at-risk individuals compared with healthy individuals (221 mm2 [81-504 mm2] vs 40 mm2 [12-205 mm2]). Patients with CCP+ at-risk had increased relative abundance of Porphyromonas gingivalis (but not Aggregatibacter actinomycetemcomitans) at healthy periodontal sites compared with healthy individuals (effect size, 3.00; 95% CI, 1.71-4.29) and patients with ERA (effect size, 2.14; 95% CI, 0.77-3.52).

CONCLUSIONS AND RELEVANCE

This study found increased prevalence of periodontitis and P gingivalis in CCP+ at-risk individuals. This suggests periodontitis and P gingivalis are associated with disease initiation and could be targets for preventive interventions in RA.

Infliximab Induced a Dissociated Response of Severe Periodontal Biomarkers in Rheumatoid Arthritis Patients

OBJECTIVE

Rheumatoid arthritis and periodontal disease are associated together, but the effect of therapy provided for one disease to the second one remained under-investigated. This study investigated effect of infliximab therapy used to treat rheumatoid arthritis (RA) on various biomarkers of periodontal disease (PD) severity including serologies of Porphyromonas gingivalis and Prevotella intermedia and matrix metalloproteinase 3.

METHODS

Seventy nine RA patients were enrolled at the time to start infliximab therapy and the 28 joint disease activity score (DAS28), anti-cyclic citrullinated petides 2nd generation (anti-CCP2), anti-P. gingivalis antibody, and Matrix metalloproteinase 3 (MMP-3) were monitored before and at 6 months of infliximab therapy. Joint damage and severe periodontal disease were assessed at baseline. Anti-CCP2, anti-P. gingivalis antibody, and MMP-3 were determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS

At baseline, anti-CCP2 titers were associated with anti-P. gingivalis lipopolysaccharide (LPS)-specific antibodies titers (p < 0.05). Anti-P. gingivalis antibodies were not significantly correlated with clinical, biological, or destruction parameters of RA disease. At 6 months of infliximab therapy, MMP-3 level decreased (from 119 ± 103 ng/mL to 62.44 ± 52 ng/mL; p < 0.0001), whereas P. gingivalis antibody levels remained at the same level. DAS28 and inflammation markers C-reactive protein (CRP) and Erythrocyte sedimentation rate (ESR) also decreased significantly during infliximab therapy (p < 0.05) as anti-CCP2 levels (p < 0.001). Only high MMP-3 level at baseline was associated with infliximab efficacy (p < 0.01).

CONCLUSION

MMP-3 level can be a useful marker of the efficacy of infliximab in RA patients. The treatment did not affect anti-P. gingivalis antibodies.