Periodontal therapy reduces plasma levels of interleukin-6, C-reactive protein, and fibrinogen in patients with severe periodontitis and refractory arterial hypertension

Non-surgical periodontal therapy reduces coronary heart disease risk markers: a randomized controlled trial

AIM

Periodontal disease elevates systemic inflammatory markers strongly associated with coronary heart disease (CHD) risk. The aim of this randomized controlled trial was to investigate the effect of non-surgical periodontal therapy on systemic C-reactive protein (CRP), fibrinogen and white blood cells in CHD patients.

MATERIALS AND METHODS

Angiographically proven CHD patients with periodontitis (n = 317) were randomized to intervention (n = 212) or control group (n = 105). Primary outcome was reduction in serum CRP levels; secondary outcomes were reductions in fibrinogen and white blood cells. Periodontal treatment included scaling, root planing and oral hygiene instructions. Periodontal and systemic parameters were assessed at baseline and at 2-month follow-up. Intent-to-treat (ITT) analysis was performed.

RESULTS

Study was completed by 246 subjects (intervention group = 161; control group = 85). Significant improvements in periodontal and systemic parameters were observed in intervention group. The number of subjects with CRP > 3mg/L in intervention group decreased by 38% and in control group increased by 4%. ITT analysis gave a significant (χ(2) =4.381, p = 0.036) absolute risk reduction of 12.5%.

CONCLUSION

In CHD patients with periodontitis, non-surgical mechanical periodontal therapy significantly reduced systemic levels of C-reactive protein, fibrinogen and white blood cells.

Description of comprehensive dental services supported by the Medicare Chronic Disease Dental Scheme in the first 23 months of operation

OBJECTIVE

Australia's Medicare universal insurance system has supported comprehensive dental service through the Chronic Disease Dental Scheme (CDDS) since November 2007. Public debate opposing CDDS includes claims of over-servicing, calls for expansion to universal eligibility, and government threat of closure. Here we examine CDDS services over the first 23 months of operation.

METHODS

CDDS statistics on patient age, gender and item numbers claimed from November 2007 to December 2009 from Medicare were subjected to analysis.

RESULTS

The distribution of 404,768 total CDDS patients varied across Australia from 3.6% of the population in NSW to 0.07% in NT, while uptake increased over time. The average patient had 7.58 dental treatments, and the most common were: direct restorations (2.27), preventive and periodontal services (1.46), diagnostic services (1.43), extractions (0.77), and new dentures (0.53). Crown and bridgework appeared over-represented (0.48).

CONCLUSION

Although data do suggest over-servicing in crown and bridgework, there also appears to be significant community need for the CDDS.

IMPLICATION

Clear guidelines for dental clinical diagnosis and treatment planning, as well as a pre-approval process for crown and bridgework is suggested to improve the CDDS, and this could form the basis for expansion to universal eligibility for dental Medicare.

Expressions of interleukin-1β and interleukin-6 within aortas and uteri of rats with various severities of ligature-induced periodontitis

To investigate the associations of periodontitis with histological lesions in some other organs, various severities of periodontitis were induced in rats by 3/0 silk ligatures tied around different numbers of their molar necks. Six weeks after the initial placement of ligatures, all rats were sacrificed by an anaesthetic overdose. The distances from the cemento-enamel junction to the alveolar bone crest within the placement zone of the ligature and their contralateral zone in groups L(2) and L(3) were measured. The levels of interleukin (IL)-1β and IL-6 in serum were assayed by enzyme-linked immunosorbent assay techniques, and those within aortas and uteri were measured by real-time polymerase chain reaction and by immunohistochemistry. We divided the ligature-induced periodontitis models into mild, moderate and severe rat periodontitis and observed that although no association between periodontitis and the serum concentrations of IL-1β was detected, the differences in the severity of rat periodontitis led to varying degrees of elevated expressions of IL-1β and IL-6 within aortas and uteri.

The effect of dental care on cardiovascular disease outcomes: an application of instrumental variables in the presence of heterogeneity and self-selection

Studies show a relationship between oral inflammatory processes and cardiovascular risk factors, suggesting that dental care may reduce the risk of cardiovascular disease (CVD) events. However, due to the differences between men and women in the development and presentation of CVD, such effects may vary by sex. We use a valid set of instrumental variables to evaluate these issues and include a test of essential heterogeneity. CVD events include new occurrences of heart attack (including death from heart attack), stroke (including death from stroke), angina, and congestive heart failure. Controls include age, race, education, marital status, foreign birthplace, and cardiovascular risk factors (health status, body mass index, alcohol use, smoking status, diabetes status, high-blood-pressure status, physical activity, and depression). Our analysis finds no evidence of essential heterogeneity. We find the minimum average treatment effect for women to be -0.01, but find no treatment effect for men. This suggests that women who receive dental care may reduce their risk of future CVD events by at least one-third. The findings may only apply to married middle-aged and older individuals as the data set is only representative for this group.

Periodontal disease is associated with higher levels of C-reactive protein in non-diabetic, non-smoking acute myocardial infarction patients

OBJECTIVES

A link between periodontal disease (PD) and cardiovascular events has been proposed, but confounding by shared risk factors such as smoking and diabetes remains a concern. We examined the prevalence of PD and its contribution to C-reactive protein (CRP) levels in acute myocardial infarction (AMI) patients and in subjects without AMI and with angiographically nonobstructive coronary disease in the absence of these confounding risk factors.

METHODS

Periodontal status and admission CRP levels were evaluated in 87 non-diabetic and non-smoking subjects undergoing cardiac catheterization. The study group comprised of 47 patients with documented AMI, and 40 subjects without AMI and with angiographically nonobstructive coronary disease (ANCD group).

RESULTS

Both the prevalence of PD and CRP levels were significantly higher in AMI patients compared with ANCD subjects (38.3% vs. 17.5%, p=0.03 and 44.3 vs. 8.5 mg/L, p<0.001 respectively). PD was associated with higher CRP levels in AMI patients (52.5 vs. 36.1 mg/L, p=0.04) as well as in ANCD subjects, however, in this group this was not significant (12.6 vs. 7.6 mg/L, p=0.5). Multivariable regression analysis confirmed two separate measures of PD as strong and independent contributors to elevated CRP levels in AMI patients (R2 = 0.28, R2 = 0.30, p=0.001).

CONCLUSIONS

PD contributes to elevated CRP levels in non-diabetic, non-smoking AMI patients, independently of other confounding factors. These findings imply that periodontitis may emerge as a novel target for reducing future risk in AMI survivors.

Mechanisms involved in the association between periodontal diseases and cardiovascular disease

It is now well accepted that besides the cholesterol associated mechanisms of atherogenesis, inflammation plays a crucial role in all stages of the development of the atherosclerotic lesion. This 'inflammation hypothesis' raises the possibility that through systemic elevations of pro-inflammatory cytokines, periodontal diseases might also contribute to systemic inflammation and, therefore, to atherogenesis. In fact, there is evidence that periodontal diseases are associated with higher systemic levels of high-sensitivity C-reactive protein and a low grade systemic inflammation. This phenomenon has been explained based on mechanisms associated with either the infectious or the inflammatory nature of periodontal diseases. The purposes of this article were to review (1) the evidence suggesting a role for oral bacterial species, particularly periodontal pathogens, in atherogenesis; (2) the potential mechanisms explaining an etiological role for oral bacteria in atherosclerosis; (3) the evidence suggesting that periodontal infections are accompanied by a heightened state of systemic inflammation; (4) the potential sources of systemic inflammatory biomarkers associated with periodontal diseases; and (5) the effects of periodontal therapy on systemic inflammatory biomarkers and cardiovascular risk.

Is periodontal inflammation associated with raised blood pressure? Evidence from a National US survey

There is incomplete and inconclusive evidence for the association between periodontal disease markers and arterial blood pressure, particularly from large national epidemiological studies. This study assessed the relationship between different markers of periodontal inflammation and disease with arterial blood pressure in people aged 17 years and over in USA. We analysed data from the Third National Health and Nutrition Examination Survey on 6617 men and 7377 women who received a periodontal examination. Blood pressure was analysed in both a continuous format and a binary variable for case definition of hypertension. Periodontal disease markers (extent of gingival bleeding, pocket depth, and loss of attachment, and a case definition of periodontitis) were associated on the arterial blood pressure outcomes through a series of regression models, incrementally adjusting for confounders (demographic, inflammation markers, chronic conditions, smoking, BMI, socio-economic status). All periodontal measures had significant crude associations with SBP and hypertension. Gingival bleeding, a marker of current periodontal inflammation, was the only measure consistently and significantly associated with raised SBP and an increased odds of hypertension in the US adult population throughout the adjustment process. For a 10% greater extent of gingival bleeding, the average SBP was higher by 0.5 (0.3, 0.6) mmHg in the fully adjusted model. By referring to the general population and the whole distribution of blood pressure, not only to those at higher risk for hypertension, this association might have some important implications for clinical practice and public health strategies.

Periodontal disease as a risk factor for cardiovascular disease: suggestion of a further link in systemic lupus erythematosus

Cardiovascular disease (CVD) is a major cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Due to either infection or disease activity, elevated levels of inflammatory markers and up-regulation of the autoimmune process can contribute to the development of atherosclerosis in SLE patients. Periodontal diseases are among the most prevalent chronic infections in humans and are characterized by pathogen-induced oral inflammatory disease affecting the supporting tissues of teeth. Several cytokines capable of inducing systemic effects are produced during the course of this infection. The presence of these cytokines can be verified by changes in the levels of C-reactive protein (CRP). Periodontal disease is a well-known risk factor for atherosclerosis. The potential for beneficial prevention of CVD events through the use of periodontal treatment has been previously recommended. This review reinforces the hypothesis that periodontal infection could be a risk factor for CVD in patients diagnosed with SLE, and suggests that by reducing the progression of this oral infection, levels of inflammatory markers common to both diseases (SLE and periodontal disease) would likely decrease.

Periodontitis and blood pressure: the concept of dental hypertension

Chronic periodontitis is a common inflammatory disorder that is being contemplated as a risk factor for atherosclerotic complications. Current epidemiological evidence also supports its potential association with increases in blood pressure levels and hypertension prevalence. Furthermore, data from cross-sectional studies suggest that in hypertensive subjects periodontitis may enhance the risk and degree of target organ damage. A possible pathogenetic background of an effect of periodontitis on blood pressure should include the systemic generalization of the local oral inflammation, the role of the host immune response, the direct microbial effect on the vascular system and alterations in endothelial function. Inversely, the concept of hypertension unfavorably affecting periodontal tissues cannot be excluded. The two conditions share multiple common risk factors that should be readily controlled for when assessing a possible association. Thoroughly designed prospective and interventional trials are needed in order to determine the impact of periodontitis on blood pressure regulation and incident hypertension and its integration in the clinical approach of both dental and hypertensive patients.

Periodontal disease as a risk marker in coronary heart disease and chronic kidney disease

PURPOSE OF REVIEW

More than half a million Americans die each year from coronary heart disease (CHD), 26 million suffer from chronic kidney disease (CKD), and a large proportion have periodontal disease, a chronic infection of the tissues surrounding teeth. Chronic inflammation contributes to CHD and CKD occurrence and progression, and periodontal disease contributes to the cumulated chronic systemic inflammatory burden. This review examines recent evidence regarding the role of periodontal disease in CHD and CKD.

RECENT FINDINGS

Periodontal pathogens cause both local infection and bacteremia, eliciting local and systemic inflammatory responses. Periodontal disease is associated with the systemic inflammatory reactant C-reactive protein (CRP), a major risk factor for both CHD and CKD. Nonsurgical periodontal disease treatment is shown to improve periodontal health, endothelial function, levels of CRP, and other inflammatory markers. Evidence for the association of periodontal disease with CKD consists of a small body of literature represented mainly by cross-sectional studies. No definitive randomized controlled trials exist with either CHD or CKD as primary endpoints.

SUMMARY

Recent evidence links periodontal disease with CHD and CKD. Adding oral health self-care and referral for professional periodontal assessment and therapy to the repertoire of medical care recommendations is prudent to improve patients' oral health and possibly reduce CHD and CKD risk.

A systematic review of the effectiveness of oral health promotion activities among patients with cardiovascular disease

AIMS

This study aimed to review the effectiveness of oral health promotion activities conducted among patients with cardiovascular disease.

METHODS AND RESULTS

Three electronic databases were searched for effective papers using standardized search methods, and key findings of effective studies were summarized. The initial search yielded 3101 papers but only 8 studies met the criteria for this review: 3 were randomized controlled studies, 3 were pre-/post group interventions, 1 was a randomized split-mouth study, and 1 was a quasi-experimental study. Studies retrieved concerned oral health promotion activities in patients with coronary heart disease, hypertension, heart transplantation, and stroke. Interventions comprised periodontal treatment performed by dental personnel, and oral hygiene interventions provided by nursing home care assistants. Outcomes included improvements in periodontal health, and modifications of systemic inflammatory markers. No studies, however, evaluated the effects of oral health promotion interventions on oral microflora.

CONCLUSION

There are limited studies on the efficacy of oral health promotion activities in patients with cardiovascular disease, particularly stroke patients. Oral health promotion activities appear to produce improvements in periodontal health, and also result in changes to systemic markers of inflammation and endothelial function (at least) in the short term. Whether these effects can ultimately lower the risk of secondary cardiovascular events has not yet been determined.

Cardiovascular disease and the role of oral bacteria

In terms of the pathogenesis of cardiovascular disease (CVD) the focus has traditionally been on dyslipidemia. Over the decades our understanding of the pathogenesis of CVD has increased, and infections, including those caused by oral bacteria, are more likely involved in CVD progression than previously thought. While many studies have now shown an association between periodontal disease and CVD, the mechanisms underpinning this relationship remain unclear. This review gives a brief overview of the host-bacterial interactions in periodontal disease and virulence factors of oral bacteria before discussing the proposed mechanisms by which oral bacterial may facilitate the progression of CVD.

Hypertension may affect tooth-supporting alveolar bone quality: a study in rats

BACKGROUND

This study evaluates the ligature-induced bone loss (BL) and quality of tooth-supporting alveolar bone in spontaneously hypertensive rats (SHRs) by histometric, histochemical, and immunohistochemical analyses and assesses the effects of lercanidipine on these parameters.

METHODS

Wistar rats and SHRs were assigned to one of the following groups: normotensive rats (n = 15), untreated SHRs (n = 15), and treated SHRs (n = 15). The latter group was treated daily with lercanidipine for 45 days. Two weeks after the beginning of drug administration, the first right mandibular molar received a cotton ligature, whereas the contralateral tooth was left unligated. The following parameters were analyzed in the furcation area of decalcified histologic sections: BL, bone density (BD), number of positive cells for tartrate-resistant acid phosphatase (TRAP+), and expression of receptor activator of nuclear factor-kappa B ligand (RANKL) and osteoprotegerin (OPG).

RESULTS

In ligated teeth, no significant differences among groups were found regarding BL, TRAP+ cells, and the ratio of RANKL/OPG+ cells (P >0.05), although the expression of RANKL was decreased in the treated SHR group (P <0.05). Increased BL and decreased BD were observed around unligated teeth of the untreated and treated SHR groups (P <0.05). In the furcation area of the unligated teeth, the untreated SHR group presented a higher number of TRAP+ cells and higher ratio of RANKL/OPG+ cells compared to the other groups.

CONCLUSIONS

SHRs present harmful alterations in the quality of tooth-supporting bone, independently of inflammation. In addition, the administration of lercanidipine for 45 days decreased the expression of bone-resorption markers.

Design, Operation, and Interpretation of Clinical Trials

Randomized controlled clinical trials offer the best evidence for changing clinical practice and informing public health policy. Using examples from the literature, this paper reviews clinical trials for those who may be unfamiliar with their design, operation, and interpretation. In the design of a clinical trial, the question to be answered and a clinically meaningful outcome must be clearly defined. Ethics must be considered, sample size carefully estimated, and use of biomarkers and surrogate outcomes understood. Prominent issues in trial implementation include developing a manual of operations, trial registration, subject recruitment and retention, use of a data coordinating center, and data and safety monitoring. Interpretation of clinical trials requires understanding differences between efficacy and effectiveness; superiority, equivalence, and non-inferiority; intent-to-treat; primary and secondary analyses; and limitations of unregistered small clinical trials compared with large multi-center Phase III trials that are more likely to be representative of a population and change clinical practice or public health policy.

Lipoproteins and lipoprotein metabolism in periodontal disease

A growing body of evidence indicates that the incidence of atherosclerosis is increased in subjects with periodontitis - a chronic infection of the oral cavity. This article summarizes the evidence that suggests periodontitis shifts the lipoprotein profile to be more proatherogenic. LDL-C is elevated in periodontitis and most studies indicate that triglyceride levels are also increased. By contrast, antiatherogenic HDL tends to be low in periodontitis. Periodontal therapy tends to shift lipoprotein levels to a healthier profile and also reduces subclinical indices of atherosclerosis. In summary, periodontal disease alters lipoprotein metabolism in ways that could promote atherosclerosis and cardiovascular disease.

The association of metabolic syndrome with periodontal disease is confounded by age and smoking in a Korean population: the Shiwha-Banwol Environmental Health Study

AIM

Because metabolic syndrome (MS) is pro-inflammatory and periodontitis is inflammatory, we issued the hypothesis that MS (the explanatory variable) is associated with periodontitis (the outcome variable). This study aimed to examine the link between MS and periodontitis among Koreans.

MATERIALS AND METHODS

From the Shiwha-Banwol Environmental Health Study, 1046 subjects aged 18 years or older were cross-sectionally surveyed. All participants underwent comprehensive dental and medical health examinations. The community periodontal index was used to assess periodontitis. Age, gender, monthly family income, smoking, drinking, frequency of daily teeth brushing, and physical activity were evaluated as confounders.

RESULTS

MS was strongly associated with periodontitis [odds ratio (OR): 1.7, 95% confidence interval (CI): 1.22-2.37], and MS with more components had a higher association. The association was higher for elders aged 65 years or more, males, and smokers. MS including both high glucose and hypertension had a higher association with the OR of 2.19 (95% CI: 1.23-3.90) comparing with other types of MS.

CONCLUSIONS

Our results suggested that MS might be associated with periodontitis and the association was confounded by age, gender, and smoking. MS with high glucose and hypertension showed the higher impact on this link.

The history of dentistry and medicine relationship: could the mouth finally return to the body?

The relationship between dentistry and medicine has been acknowledged throughout the history of humanity. This relationship was documented in ancient medicine accounts, and has survived until the present day, accompanied by the evolution of molecular technologies. Although we have had very important researchers' contributions in this interdisciplinary area, mainly after the 18th century, the knowledge on oral infections is still ignored by or unknown to the majority of clinical dentists and physicians. These circumstances could be changed through a broader divulgation of this complex relationship, both in the dentistry and in the medicine areas, which in turn would have a significant impact in systemic health worldwide. This movement has already started, as was observed in a World Health Assembly resolution which called for oral health to be integrated into chronic disease prevention programs in 2007. This was a significant indicator of changing perceptions of oral health over the past several decades. This brief review reports the evolution through time of the knowledge on the association between dental infections and systemic diseases, as well as the paths which we could take to consolidate this historical trend.