Metabolic diseases and their possible link to risk indicators of periodontitis

Inflammation indices in association with periodontitis and cancer

Inflammation is a complex physiological process that plays a pivotal role in many if not all pathological conditions, including infectious as well as inflammatory diseases, like periodontitis and autoimmune disorders. Inflammatory response to periodontal biofilms and tissue destruction in periodontitis is associated with the release of inflammatory mediators. Chronic inflammation can promote the development of cancer. Persistence of inflammatory mediators plays a crucial role in this process. Quantification and monitoring of the severity of inflammation in relation to cancer is essential. Periodontitis is mainly quantified based on the severity and extent of attachment loss and/or pocket probing depth, in addition with bleeding on probing. In recent years, studies started to investigate inflammation indices in association with periodontal diseases. To date, only few reviews have been published focusing on the relationship between blood cell count, inflammation indices, and periodontitis. This review presents a comprehensive overview of different systemic inflammation indices, their methods of measurement, and the clinical applications in relation to periodontitis and cancer. This review outlines the physiological basis of inflammation and the underlying cellular and molecular mechanisms of the parameters described. Key inflammation indices are commonly utilized in periodontology such as the neutrophil to lymphocyte ratio. Inflammation indices like the platelet to lymphocyte ratio, platelet distribution width, plateletcrit, red blood cell distribution width, lymphocyte to monocyte ratio, delta neutrophil index, and the systemic immune inflammation index are also used in hospital settings and will be discussed. The clinical roles and limitations, relationship to systemic diseases as well as their association to periodontitis and treatment response are described.

Oral biosciences: The annual review 2023

BACKGROUND

The Journal of Oral Biosciences is dedicated to advancing and disseminating fundamental knowledge with regard to every aspect of oral biosciences. This review features review articles in the fields of "bone regeneration," "periodontitis," "periodontal diseases," "salivary glands," "sleep bruxism," and "Sjögren's syndrome."

HIGHLIGHT

This review focuses on human demineralized dentin and cementum matrices for bone regeneration, oxidized low-density lipoprotein in periodontal disease and systemic conditions, the relationship between inflammatory mediators in migraine and periodontitis, phosphoinositide signaling molecules in the salivary glands, and the pathophysiologies of sleep bruxism and Sjögren's syndrome.

CONCLUSION

The review articles featured in the Journal of Oral Biosciences have broadened the knowledge of readers regarding various aspects of oral biosciences. The current editorial review discusses the findings and significance of these review articles.

The etiological consideration of oxidized low-density lipoprotein in periodontitis

BACKGROUND

Epidemiologically, correlations between periodontal disease activity and CVD/serum lipid-related condition have been reported. Known mediators of these links include triglycerides, oxidized LDL (oxLDL) and inflammatory cytokines such as TNF-α supplied by adipocytes as well as oxidative degeneration products of these lipids. In this review, we focused on oxidized LDL and considered the relationship between periodontal disease and systemic conditions.

HIGHLIGHT

The degree of oxidation in the periodontal pocket can be evaluated by analyzing the Gingival Cervicular Fluid (GCF), which can be easily collected with paperpoint. The oxLDL/LDL ratio in GCF has been shown to be 17 times as high as that in blood, and IL-8 and IL-1β were also abundantly found in GCF. Periodontal treatment significantly lowers oxLDL levels in not only GCF but also plasma. In addition, there has been growing body of evidence that periodontal infections by periodontopathic bacteria affect arteriosclerosis. On the other hands, neutrophil extracellular traps (NETs), a form of innate immune responses, reportedly play a role as a defense mechanism in the periodontal pockets. However, the regulatory mechanism of NETs in periodontal pocket is still unknown. Recently, NETs induced by oxidized cholesterol have been reported to be involved in inflammatory damage to vascular endothelial cells.

CONCLUSION

Further understanding of the newly discovered roles of oxLDL in the defense and destruction of periodontal tissues are anticipated.

Radiographic Bone Loss and Its Relation to Patient-Specific Risk Factors, LDL Cholesterol, and Vitamin D: A Cross-Sectional Study

The influence of patient-specific factors such as medical conditions, low-density lipoprotein cholesterol (LDL-C) or levels of 25-hydroxyvitamin D (25OHD) on periodontal diseases is frequently discussed in the literature. Therefore, the aim of this retrospective cross-sectional study was to evaluate potential associations between radiographic bone loss (RBL) and patient-specific risk factors, particularly LDL-C and 25OHD levels. Patients from a dental practice, who received full-mouth cone beam CTs (CBCTs) and blood-sampling in the course of implant treatment planning, were included in this study. RBL was determined at six sites per tooth from CBCT data. LDL-C and 25OHD levels were measured from venous blood samples. Other patient-specific risk factors were assessed based on anamnesis and dental charts. Statistical analysis was performed applying non-parametric procedures (Mann-Whitney U tests, error rates method). Data from 163 patients could be included in the analysis. RBL was significantly higher in male patients, older age groups, smokers, patients with high DMFT (decayed/missing/filled teeth) score, lower number of teeth, and high LDL-C levels (≥160 mg/dL). Furthermore, patients with high 25OHD levels (≥40 ng/mL) exhibited significantly less RBL. In summary, RBL was found to be associated with known patient-specific markers, particularly with age and high LDL-C levels.

Impact of Impaired Glucose Metabolism on Periodontitis Progression over Three Years

We evaluated the relationship between glucose abnormalities and periodontitis in overweight/obese individuals. Eight hundred and seventy (870) diabetes-free participants aged 40-65 years completed the three-year follow-up in the San Juan Overweight Adults Longitudinal Study. The ADA thresholds for fasting and 2-h post-load glucose and HbA1c were used to define prediabetes. The NHANES methods were used to assess periodontitis. Multivariable linear regression was used to evaluate the relationship between baseline glucose metabolism measures and periodontitis at follow-up, adjusting for potential confounders. There was no association between impaired glucose measures and mean pocket depth (PD), mean clinical attachment loss (CAL), or mean percent of sites ≥5 mm PD. Impaired glucose tolerance (IGT) was associated with a lower mean percent of sites ≥5 mm CAL (β = -1.6, p = 0.037). Prediabetes and impaired fasting glucose (IFG) were associated with improvement in mean percent of sites ≥5 mm PD (β = -1.4, p = 0.022; β = -1.6, p = 0.032; respectively). IFG and IGT were associated with improvement in mean percent of sites with ≥5 mm CAL (β = -1.6, p = 0.038; β = -1.9, p = 0.020; respectively). In conclusion, there were no consistent associations between baseline prediabetes or insulin resistance and periodontitis progression over a three-year period.

Association between metabolic syndrome and periodontitis: The role of lipids, inflammatory cytokines, altered host response, and the microbiome

Periodontitis has been associated with many systemic diseases and conditions, including metabolic syndrome. Metabolic syndrome is a cluster of conditions that occur concomitantly and together they increase the risk of cardiovascular disease and double the risk of type 2 diabetes. In this review, we focus on the association between metabolic syndrome and periodontitis; however, we also include information on diabetes mellitus and cardiovascular disease, since these two conditions are significantly intertwined with metabolic syndrome. With regard to periodontitis and metabolic syndrome, to date, the vast majority of studies point to an association between these two conditions and also demonstrate that periodontitis can contribute to the development of, or can worsen, metabolic syndrome. Evaluating the effect of metabolic syndrome on the salivary microbiome, data presented herein support the hypothesis that the salivary bacterial profile is altered in metabolic syndrome patients compared with healthy patients. Considering periodontitis and these three conditions, the vast majority of human and animal studies point to an association between periodontitis and metabolic syndrome, diabetes, and cardiovascular disease. Moreover, there is evidence to suggest that metabolic syndrome and diabetes can alter the oral microbiome. However, more studies are needed to fully understand the influence these conditions have on each other.

Comparing the Frequency of Some Oral Lesions in Prediabetic and Healthy Individuals: Is There Any Difference?

BACKGROUND

Diagnosis of prediabetic stage is very important for prevention of diabetes and complications. This stage may be associated with some oral lesions. Only a few studies are available on the oral status of prediabetic patients and incidence of oral lesions in this population. This study aimed to compare some oral complications between prediabetic and healthy control groups.

METHODS

The present two-group cross-sectional study was carried out on 302 prediabetic and non-diabetic (healthy) 20- to 60-year-old subjects. In this study, data on age, gender, educational level, medications use, smoking, and some other variables were extracted through history taking. In addition, orodental examination was carried out by an oral medicine specialist to diagnose oral lesions including candidiasis, lichen planus, periodontitis, gingivitis, xerostomia, delayed wound healing, geographic tongue, fissured tongue, and burning mouth sensation. Data entry and analysis was performed by SPSS version 22 software, and P value and odds ratio (OR) were calculated to show statistical relationship between variables.

RESULTS

The most common oral lesion in prediabetic subjects was periodontitis (27.2%), followed by gingivitis (14.7%) and xerostomia (11.3%). In the control group, gingivitis (20.5%) followed by periodontitis (11.3%) are common oral lesions. Candidiasis (P = 0.036), periodontitis (P < 0.001), and xerostomia (P < 0.001) in prediabetic subjects were higher than control group that is statistically significant. Regression analysis showed that in the prediabetic group, periodontitis [OR = 2.91, confidence interval (CI): 1.54-5.49] and xerostomia (OR = 18.51, CI = 2.42-141.45) were significantly more prevalent than healthy subjects.

CONCLUSION

Based on the results, glucose intolerance stage exhibited a significantly higher oral problems such as periodontitis and xerostomia than healthy euglycemic stage.

Critical Appraisal of Bidirectional Relationship between Periodontitis and Hyperlipidemia

Periodontal disease and hyperlipidemia are both multifactorial disease with a high prevalence Worldwide. Cross-sectional and longitudinal prospective clinical studies show some evidence for a bidirectional relationship. Periodontitis and hyperlipidemia share some common risk factors and there exist a mechanistic link between both. Studies have found a positive response to periodontal therapy among hyperlipidemic patients, and statin use by hyperlipidemic patients has shown to influence the periodontal health. However, in spite of the rising prevalence of both diseases, many people remain unaware of their association with each other. Hence, this article summarizes the cyclic relationship between periodontal disease and hyperlipidemia.

Toll-like receptor 2 activation primes and upregulates osteoclastogenesis via lox-1

BACKGROUND

Lectin-like oxidized low-density-lipoprotein receptor 1 (Lox-1) is the receptor for oxidized low-density lipoprotein (oxLDL), a mediator in dyslipidemia. Toll-like receptor (TLR)-2 and - 4 are receptors of lipopolysaccharide (LPS) from Porphyromonas gingivalis, a major pathogen of chronic periodontitis. Although some reports have demonstrated that periodontitis has an adverse effect on dyslipidemia, little is clear that the mechanism is explained the effects of dyslipidemia on osteoclastogenesis. We have hypothesized that osteoclast oxLDL has directly effect on osteoclasts (OCs), and therefore alveolar bone loss on periodontitis may be increased by dyslipidemia. The present study aimed to elucidate the effect of Lox-1 on osteoclastogenesis associated with TLRs in vitro.

METHODS

Mouse bone marrow cells (BMCs) were stimulated with macrophage colony-stimulating factor into bone marrow macrophages (BMMs). The cells were also stimulated with synthetic ligands for TLR2 (Pam3CSK4) or TLR4 (Lipid A), with or without receptor activator of nuclear factor kappa-B ligand (RANKL), and assessed for osteoclastogenesis by tartrate-resistant acid phosphatase (TRAP) staining, immunostaining, western blotting, flow activated cell sorting (FACS) analysis, real-time polymerase chain reaction (PCR), and reverse transcription PCR.

RESULTS

Lox-1 expression was significantly upregulated by Pam3CSK4 and Lipid A in BMCs (p < 0.05), but not in BMMs. FACS analysis identified that Pam3CSK4 upregulated RANK and Lox-1 expression in BMCs. TRAP-positive cells were not increased by stimulation with Pam3CSK4 alone, but were increased by stimulation with combination combined Pam3CSK and oxLDL. Expression of both Lox-1 and myeloid differentiation factor 88 (MyD88), an essential adaptor protein in the TLR signaling pathway, were suppressed by inhibitors of TLR2, TLR4 and mitogen-activated protein kinase (MAPK).

CONCLUSIONS

This study supports that osteoclastogenesis is promoted under the coexistence of oxLDL by TLR2-induced upregulation of Lox-1 in BMCs. This indicates that periodontitis could worsen with progression of dyslipidemia.

Cross-sectional associations of impaired glucose metabolism measures with bleeding on probing and periodontitis

AIM

This study assessed the associations of pre-diabetes and insulin resistance with bleeding on probing (BOP) and periodontitis among adults.

MATERIALS AND METHODS

We included 1191 Hispanic adults aged 40-65 years, free of diabetes, enrolled in San Juan Overweight Adults Longitudinal Study. Pre-diabetes was defined as impaired fasting glucose (IFG), impaired glucose tolerance (IGT), or impaired glycated haemoglobin. Impaired one-hour plasma glucose (1hPG) was defined as levels >155 mg/dl. Insulin resistance was defined using the study population-specific 75th percentile (HOMA-IR ≥ 3.13). High BOP was defined as percentage of teeth with bleeding ≥30%. Periodontitis was defined according to the CDC/AAP definition.

RESULTS

After multivariable adjustment for age, gender, education, smoking status, alcohol consumption, physical activity, obesity, HDL-C, and plaque index, pre-diabetes with and without 1hPG, IFG, impaired 1hPG, IGT, and HOMA-IR were significantly associated with high BOP; pre-diabetes, IFG, and impaired 1hPG were significantly associated with severe periodontitis. Most of these associations remained significant when the analyses were restricted to non-smokers.

CONCLUSIONS

This study suggests associations between pre-diabetes and insulin resistance with BOP and periodontitis. Given the high prevalence of impaired glucose metabolism and periodontitis, the assessment of the temporal sequence of these associations is of utmost importance.

Relationship of Metabolic Syndrome to Periodontal Disease in Japanese Women: The Hisayama Study

Recent studies have suggested that several systemic conditions—such as obesity, hypertension, hyperlipidemia, and diabetes—are related to periodontitis. The objective of this study was to examine the relationship between periodontitis and 5 components of metabolic syndrome—abdominal obesity, triglyceride level, high-density lipoprotein cholesterol level, blood pressure, and fasting blood sugar level—in 584 Japanese women. In multivariate analyses, persons exhibiting more components of metabolic syndrome had significantly higher odds ratios for a greater pocket depth and clinical attachment loss than did those with no components; the odds ratios for a greater pocket depth and clinical attachment loss of the persons exhibiting 4 or 5 components were 6.6 (95% confidence interval = 2.6–16.4) and 4.2 (95% confidence interval = 1.2–14.8), respectively. These results indicate that metabolic syndrome increases risk of periodontitis, and suggest that people exhibiting several components of metabolic syndrome should be encouraged to undergo a periodontal examination.

Low frequency of toothbrushing practices is an independent risk factor for diabetes mellitus in male and dyslipidemia in female: A large-scale, 5-year cohort study in Japan

BACKGROUND

We previously reported the association between toothbrushing practices and diabetes mellitus (DM) and dyslipidemia (DL) in a cross-sectional study. This study was conducted to clarify whether low frequency of toothbrushing practices is an independent risk factor for DM and DL using a follow-up design.

METHODS

This study was a 5-year retrospective cohort study at St. Luke's International Hospital, Tokyo, Japan. We analyzed study subjects between 30 and 85 years old in 2004, who underwent annual medical examination both in 2004 and 2009. We compared the cumulative incidences of developing DM, DL, hypertension (HT), and hyperuricemia (HUA) between 2004 and 2009 among 3 groups: toothbrushing practices 'after every meal,' 'at least once a day,' and 'less than once a day'. Furthermore, we analyzed odds ratios (ORs) of risk for developing DM and DL by sex after making adjustments for age, obesity, DM, DL, HT, and HUA between two groups: 'after every meal' and 'not after every meal.'

RESULTS

The number of study subjects was 13,070. Of 13,070 study subjects, 575 had DM, 5118 had DL, 2599 had HT, and 1908 had HUA in 2004. We excluded the subjects with each disease in 2004. The cumulative incidences (rates) of DM, DL, HT, and HUA between 2004 and 2009 were 318 (2.5%), 1454 (18.3%), 1108 (10.6%), and 489 (4.4%), respectively. Toothbrushing practices 'not after every meal' was a significant risk factor for developing DM in male [OR: 1.43; 95% confidence interval (CI), 1.040-1.970] and developing DL in female (OR: 1.18; 95% CI, 1.004-1.383) compared with toothbrushing practices 'after every meal.'

CONCLUSION

Toothbrushing practices 'after every meal' prevented developing DM in males and DL in females significantly. Toothbrushing practices may be beneficial to reduce developing risk factors for cardiovascular disease.

The Prevalence and Associated Factors of Periodontitis According to Fasting Plasma Glucose in the Korean Adults: The 2012-2013 Korea National Health and Nutrition Examination Survey

Although the relationship between diabetes and periodontitis is well established, the association between periodontitis and prediabetes has been investigated less extensively. Furthermore, there has been little research on the prevalence of periodontitis among individuals with prediabetes and diabetes as well as in the overall population using nationally representative data.Among 12,406 adults (≥19 years' old) who participated in the 2012-2013 Korea National Health and Nutrition Examination Survey, a total of 9977 subjects completed oral and laboratory examinations and were included in this analysis. Periodontitis was defined as a community periodontal index score of ≥ 3 according to the World Health Organization criteria. The fasting plasma glucose level was categorized into the following 5 groups: normal fasting glucose (NFG) 1 (<90  mg/dL), NFG 2 (90-99  mg/dL), impaired fasting glucose (IFG) 1 (100-110  mg/dL), IFG 2 (111-125  mg/dL), and diabetes (≥126  mg/dL).Overall, the weighted prevalence of periodontitis among the Korean adult population was 24.8% (23.3-26.4%) (weight n = 8,455,952/34,086,014). The unadjusted weighted prevalences of periodontitis were 16.7%, 22.8%, 29.6%, 40.7%, and 46.7% in the NFG 1, NFG 2, IFG 1, IFG 2, and diabetes groups, respectively (P < 0.001). After adjusting for age, sex, smoking history, heavy alcohol drinking, college graduation, household income, waist circumference, serum triglyceride level, serum high-density lipoprotein cholesterol level, and the presence of hypertension, the adjusted weighted prevalence of periodontitis increased to 29.7% in the IFG 2 group (P = 0.045) and 32.5% in the diabetes group (P < 0.001), compared with the NFG 1 group (24%). The odds ratios for periodontitis with the above-mentioned variables as covariates were 1.42 (95% confidence interval [CI] 1.14-1.77, P = 0.002) in the diabetes group and 1.33 (95% CI 1.01-1.75, P = 0.044) in the IFG 2 group, respectively, compared with the NFG1 group.In conclusion, a higher range of IFG levels as well as diabetes, were positively associated with chronic periodontitis in a representative sample of Korean adults. This study suggests that individuals with a higher range of IFG levels before diabetes are at risk of periodontitis, and may benefit from dental screening.

Lipoxin A4 and Neutrophil/Lymphocyte Ratio: A Possible Indicator in Achieved Systemic Risk Factors for Periodontitis

Background

The aim of this study was to evaluate the serum lipoxin A₄ (LXA₄) and neutrophil/lymphocyte (Ne/Ly) ratio in individuals with achieved systemic risk factors for periodontitis.

Material/Methods

One hundred and eighty volunteers (69 male, 111 female) who were categorized as systemically healthy control, diabetes, hyperlipidemia, obese and menopause were recruited for this cross-sectional study. Sociodemographic characteristics and oral health behaviors were recorded via questionnaire. Clinical periodontal parameters, including plaque index (PI), gingival index (GI), probing pocket depth (PD), clinical attachment level (CAL), sulcus bleeding index (SBI) and decayed, missing, and filled teeth index (DMFT), were assessed. Systemic parameters and LXA₄ levels were evaluated in serum samples.

Results

Clinical periodontal parameters and DMFT were higher in subjects with achieved systemic risk factors than in healthy subjects. The systemically healthy with periodontitis group had higher serum LXA₄ levels than the systemically healthy with non-periodontitis group (P<0.05). The Ne/Ly ratio was higher in the hyperlipidemic group with periodontitis than in the hyperlipidemic group with non-periodontitis (P<0.05). In the control group, serum LXA₄ levels were positively correlated with the PD, CAL and SBI.

Conclusions

In the presence of periodontitis, an increase in LXA₄ levels and the Ne/Ly ratio in hyperlipidemic patients could contribute to the hypothesis that these parameters could be an indicator in periodontitis and its systemic risk factors.

Association of lipid profile test values, type-2 diabetes mellitus, and periodontitis

Objective:

A two-way relationship between diabetes and periodontal disease has been suggested; whereas obesity and impaired lipid profile are risk factors for type-2 diabetes mellitus. This study examined the relationship between lipid profile, oral glucose tolerance test (OGTT) with periodontal health/disease dependent variables in healthy, diabetic and impaired glucose tolerance subjects.

Materials and Methods:

120 patients were selected for the study and were determined to be periodontally healthy or diseased. All these patients underwent biochemical tests for OGTT and Lipid profile analysis and data was compared using Z-test.

Results:

The OGTT results deteriorated with deteriorating periodontal condition. A similar correlation was also observed between worsening lipid profile test values, OGTT score, and periodontal condition.

Conclusion:

This study indicates that hyperlipidemia may be one of the factors associated with periodontitis and that periodontitis may itself lead to abnormal serum lipid levels. Therefore, in addition to effects on diabetes, periodontitis may contribute to elevated serum lipid levels and therefore potentially to systemic disease arising from chronic hyperlipidemia.

Effects of non-surgical periodontal therapy on serum lipids and C-reactive protein among hyperlipidemic patients with chronic periodontitis

Aim:

To evaluate the effect of non-surgical periodontal therapy on plasma lipid levels in hyperlipidemic patients with chronic periodontitis.

Materials and Methods:

After considering the inclusion and exclusion criteria, 30 hyperlipidemic patients with chronic periodontitis in the age group of 30–70 years, undergoing treatment in Ahmed Gasim Cardiac and Renal transplant Centre in north Sudan were recruited for the study. Patients were randomly assigned to the study and control groups. The study group received non-surgical periodontal therapy – oral hygiene instructions, scaling and root planing. The control group participants received only oral hygiene instructions. Lipid profile [total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), triglycerides (TG)], C-reactive protein (CRP), and periodontal parameters [Plaque index (PI), Gingival index (GI), probing pocket depth (PD), and attachment loss (ATL)] were measured and compared at baseline and after 3 months of the respective intervention. Between-groups analysis was done using independent “t” test and within-group analysis was done using dependent “t” test.

Results:

At baseline, groups were comparable based on lipid profile and periodontal parameters. After 3 months, the control group showed significant decrease in the PI and GI scores while there was no significant change in the other parameters. However, the study group showed significant decrease in the LDL and CRP levels along with a significant decrease in PD, ATL, PI, and GI scores, compared to the baseline values.

Conclusion:

Local non-surgical periodontal therapy resulted in improved periodontal health, with significant decrease in the LDL and CRP levels in hyperlipidemic patients with chronic periodontitis. Hence, local non-surgical periodontal therapy may be considered as an adjunct in the control of hyperlipidemia, along with standard care.

Serum α-Tocopherol Has a Nonlinear Inverse Association with Periodontitis among US Adults

BACKGROUND

Previous experimental models suggest that vitamin E may ameliorate periodontitis. However, epidemiologic studies show inconsistent evidence in supporting this plausible association.

OBJECTIVE

We investigated the association between serum α-tocopherol (αT) and γ-tocopherol (γT) and periodontitis in a large cross-sectional US population.

METHODS

This study included 4708 participants in the 1999-2001 NHANES. Serum tocopherols were measured by HPLC and values were adjusted by total cholesterol (TC). Periodontal status was assessed by mean clinical attachment loss (CAL) and probing pocket depth (PPD). Total periodontitis (TPD) was defined as the sum of mild, moderate, and severe periodontitis. All measurements were performed by NHANES.

RESULTS

Means ± SDs of serum αT:TC ratio from low to high quartiles were 4.0 ± 0.4, 4.8 ± 0.2, 5.7 ± 0.4, and 9.1 ± 2.7 μmol/mmol. In multivariate regression models, αT:TC quartiles were inversely associated with mean CAL (P-trend = 0.06), mean PPD (P-trend < 0.001), and TPD (P-trend < 0.001) overall. Adjusted mean differences (95% CIs) between the first and fourth quartile of αT:TC were 0.12 mm (0.03, 0.20; P-difference = 0.005) for mean CAL and 0.12 mm (0.06, 0.17; P-difference < 0.001) for mean PPD, whereas the corresponding OR for TPD was 1.65 (95% CI: 1.26, 2.16; P-difference = 0.001). In a dose-response analysis, a clear inverse association between αT:TC and mean CAL, mean PPD, and TPD was observed among participants with relatively low αT:TC. No differences were seen in participants with higher αT:TC ratios. Participants with γT:TC ratio in the interquartile range showed a significantly lower mean PPD than those in the highest quartile.

CONCLUSIONS

A nonlinear inverse association was observed between serum αT and severity of periodontitis, which was restricted to adults with normal but relatively low αT status. These findings warrant further confirmation in longitudinal or intervention studies.

The association between hyperlipidemia and periodontal infection

BACKGROUND

Periodontitis is a local chronic inflammatory condition of the supporting structures of the teeth resulting from a dental plaque biofilm attached to teeth surfaces. Recent studies have indicated that this oral disease may have effects on systemic health.

OBJECTIVES

The aim of the present study was to evaluate the association between periodontitis and hyperlipidemia.

PATIENTS AND METHODS

This case-control study was conducted in Iran during March 2011. In this case-control study, levels of serum lipids in 45 subjects with periodontitis were measured and compared with 45 age, gender and body mass index (BMI) matched controls. Data were analyzed using student t-test and chi-square test with P < 0.05 as the limit of significance.

RESULTS

Mean values of total cholesterol (CHL) (periodontitis group = 218.11 ± 29.77, control group = 162.31 ± 48.24) and triglycerides (TG) (periodontitis group = 209.77 ± 44.30, control group = 125.60 ± 44.16) were significantly higher in the periodontitis group (P < 0.001). High-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol levels were higher in the case group, but this difference was not statistically significant. Frequency of pathological values of CHL and TG were significantly higher in cases compared with the controls (P = 0.002 and P = 0.015, respectively).

CONCLUSIONS

This study indicates that hyperlipidemia may be associated with periodontal disease in healthy individuals; yet whether periodontitis causes an increase in levels of plasma lipids or whether hyperlipidemia is a risk factor for periodontal infection and cardiovascular disease, it needs further investigations.

Role of insulin sensitivity and beta cell function in the development of periodontal disease in adults without diabetes

AIM

The goal of this study was to explore whether insulin resistance and beta cell function are related to periodontal pocket formation, indicative of infectious periodontal disease in non-smoking adults without manifest diabetes.

MATERIAL AND METHODS

We analysed data from a Health 2000 Survey consisting of dentate subjects without any indication of diabetes, aged between 30 and 64, who had never smoked and who had participated in the Follow-up Study on Finnish Adults' Oral Health about 4 years later (n = 157). The Homeostasis Model Assessment Indices were used to measure insulin resistance (HOMA-IR) and β-cell function (HOMA-B). The development of periodontal disease was measured by means of the incidence of deepened periodontal pockets (4 mm deep or deeper) during the follow-up period. Incidence rate ratios (IRR) were estimated using Poisson regression models.

RESULTS

Both HOMA-IR and HOMA-B indices were associated with periodontal pocket formation during the 4-year follow-up.

CONCLUSION

The results of this follow-up study suggest that impaired glucose metabolism measured as insulin resistance and altered beta cell function predict the breakdown of periodontal tissues. Further studies about their role in the pathogenesis of periodontal diseases are needed.

Severity of periodontal disease in adult patients with diabetes mellitus in relation to the type of diabetes

BACKGROUND

The purpose of this study was to evaluate associations between diabetes mellitus - related factors and periodontal parameters among adult patients with diabetes mellitus, with respect to type of diabetes.

METHODS

Study participants were 179 randomly selected 18-62-year-aged patients with type 1 diabetes mellitus and 87 randomly selected 32-70-year-aged patients with type 2 diabetes. Metabolic control of diabetes was determined by the values of glycosylated haemoglobin (HbA1c). The periodontal status of all patients was evaluated by simplifying oral debris index (DI-S), probing pocket depth (PPD), gingival recession (GR), clinical attachment level (CAL), and bleeding on probing (BOP). Data analysis was performed with respect to patients' age, diabetes duration, metabolic control level, and diabetes type. Binary regression was used to test relationship of various parameters with CAL.

RESULTS

All periodontal estimates were significantly higher among patients with type 2 diabetes. The periodontal disease was more severe in >45-year-aged participants and with DI-S>1. In patients with type 1 diabetes, the disease duration >12 years was negatively related to most periodontal parameters. No significant correlation between the periodontal estimates and HbA1c was observed in either group. The significant predictors of severe periodontal disease were type 2 diabetes mellitus (OR = 2.356), duration of disease (OR = 1.827), high BOP (OR = 3.343) and DI-S (OR = 2.958).

CONCLUSIONS

Severity of periodontal disease is related to diabetes type, being more pronounced in patients with type 2 diabetes patients than in patients with type 1 diabetes. Dental plaque seems to be the major contributing factor for all patients with progressive periodontitis.

Potential association between prediabetic conditions and gingival and/or periodontal inflammation

AIMS/INTRODUCTION

Prediabetic conditions, which include impaired fasting glucose (IFG) and impaired glucose tolerance (IGT), might be associated with chronic gingival and/or periodontal inflammation. However, the occurrence of this oral inflammation in prediabetic conditions is poorly understood. The present study aimed to assess the association between prediabetes and gingival and/or periodontal inflammation.

MATERIALS AND METHODS

A total of 94 Puerto Rican men and women aged 40-65 years, who were residents of San Juan, Puerto Rico, and free of diabetes, were included in the study. All participants had at least one tooth site with clinical attachment loss ≥3 mm. Fasting and 2-h plasma glucose were collected. Gingival/periodontal inflammation was assessed by bleeding on gentle probing of the sulcus at six sites per tooth.

RESULTS

Participants with the percentage of teeth with bleeding on probing (BOP) equal to or greater than the median were compared with those with the percentage of teeth with BOP less than median. Participants with high BOP tended to present higher IFG (odds ratio [OR] 5.5, 95% confidence interval [CI] 1.2-25.3) and/or prediabetic condition (OR 3.6, 95% CI 1.0-13.2) than those with a low percentage of BOP, adjusting for age, sex, smoking, alcohol consumption, waist circumference and number of missing teeth. Using the continuous form of the outcome, the corresponding adjusted least squares means of percentage of BOP were 26.8 (standard error of the mean [SEM] 2.3) and 43.8 (SEM 6.0) in normal and IFG, respectively (P = 0.01), and 27.0 (SEM 2.4) and 39.0 (SEM 5.3) among healthy and prediabetic individuals, respectively (P = 0.05).

CONCLUSION

IFG and/or prediabetes are strongly associated with BOP, a marker of chronic gingival/periodontal inflammation.

Nicotine-induced expression of low-density lipoprotein receptor in oral epithelial cells

Background

Nicotine use is one of the most important risk factors for the development of cardiovascular and periodontal diseases. Numerous reports have suggested the possible contribution of disturbed lipid metabolism for the development of both disease groups. Despite these observations, little is known about the relationship between tobacco smoking and the development of these diseases. Our previous microarray data revealed that nicotine induced low-density lipoprotein receptor (LDLR) expression in oral epithelial cells (OECs). The aim of the present study was to confirm nicotine-mediated LDLR induction and to elucidate the signaling mechanisms leading to the augmented expression of LDLR in OECs.

Methods and Results

LDLR and nicotinic acetylcholine receptor (nAChR) subunit expression was detected by real-time PCR. The production of LDLR was demonstrated by immunofluorescence staining. nAChR-mediated LDLR induction was examined by pre-incubation of the cells with its specific inhibitor, α-bungarotoxin (α-BTX). The functional importance of transcription factor specific protein 1 (Sp1) was examined by luciferase assay, mithramycin pre-incubation or by small interfering RNA (siRNA) transfection. The specific binding of Sp1 to R3 region of LDLR 5’-untranslated region was demonstrated with electrophoretic mobility shift assay (EMSA) and streptavidin-agarose precipitation assay followed by western blotting. The results confirmed that nicotine induced LDLR expression at the transcriptional level. Nicotine was sensed by nAChR and the signal was transduced by Sp1 which bound to the R3 region of LDLR gene. Augmented production of LDLR in the gingival epithelial cells was further demonstrated by immunofluorescence staining using the gingival tissues obtained from the smoking patients.

Conclusions

Taken together, the results suggested that nicotine might contribute to the development of both cardiovascular and periodontal diseases by inducing the LDLR in OECs thereby disturbing lipid metabolism.

Periodontal status in subjects with hyperlipidemia and determination of association between hyperlipidemia and periodontal health: a clinicobiochemical study

AIM

The aim of this study was to assess the periodontal status in subjects with hyperlipidemia and to determine whether there is any association between hyperlipidemia and periodontitis.

MATERIALS AND METHODS

Sixty subjects with hyperlipidemia and 60 normolipidemic subjects participated in the study. Biochemical parameters assessed included plasma triglyceride, total cholesterol, low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) levels. Periodontal parameters assessed included plaque index (PI), probing depth (PD), clinical attachment level (CAL) and percentage of sites with bleeding on probing (BOP).

RESULTS

Hyperlipidemic patients showed signifcantly higher values across the four periodontal parameters. Plasma triglycerides, total cholesterol, LDL-C were signifcantly and positively associated with PD, BOP and CAL (p = 0.05). Whereas HDL-C levels were signifcantly and negatively associated with PD, BOP and CAL (p = 0.05).

CONCLUSION

Patients with hyperlipidemia manifested higher values of periodontal parameters compared to control group. Poorly controlled hyperlipidemia had a destructive impact on periodontium. A cyclic relationship exists between serum lipids, periodontitis and systemic health. Clinical signifcance: The relationship between periodontium and systemic factors is bidirectional and interlinked. Therefore, dentists and physicians should take this into account while treating patients, aiming for the overall betterment of the patient.

Hyperlipidemia impaired innate immune response to periodontal pathogen porphyromonas gingivalis in apolipoprotein E knockout mice

A finely-tuned innate immune response plays a pivotal role in protecting host against bacterial invasion during periodontal disease progression. Hyperlipidemia has been suggested to exacerbate periodontal health condition. However, the underlying mechanism has not been addressed. In the present study, we investigated the effect of hyperlipidemia on innate immune responses to periodontal pathogen Porphyromonas gingivalis infection. Apolipoprotein E-deficient and wild-type mice at the age of 20 weeks were used for the study. Peritoneal macrophages were isolated and subsequently used for the study of viable P. gingivalis infection. ApoE^−/− mice demonstrated inhibited iNOS production and impaired clearance of P. gingivalis in vitro and in vivo; furthermore, ApoE^−/− mice displayed disrupted cytokine production pattern in response to P. gingivalis, with a decreased production of tumor necrosis factor-α, interleukin-6 (IL-6), IL-1β and monocyte chemotactic protein-1. Microarray data demonstrated that Toll-like receptor (TLR) and NOD-like receptor (NLR) pathway were altered in ApoE^−/− mice macrophages; further analysis of pattern recognition receptors (PRRs) demonstrated that expression of triggering receptors on myeloid cells-1 (TREM-1), an amplifier of the TLR and NLR pathway, was decreased in ApoE^−/− mice macrophages, leading to decreased recruitment of NF-κB onto the promoters of the TNF-α and IL-6. Our data suggest that in ApoE^−/− mice hyperlipidemia disrupts the expression of PRRs, and cripples the host’s capability to generate sufficient innate immune response to P. gingivalis, which may facilitate immune evasion, subgingival colonization and establishment of P. gingivalis in the periodontal niche.

Involvement of toll-like receptor 2 and 4 in association between dyslipidemia and osteoclast differentiation in apolipoprotein E deficient rat periodontium

Background

Dyslipidemia increases circulating levels of oxidized low-density lipoprotein (OxLDL) and this may induce alveolar bone loss through toll-like receptor (TLR) 2 and 4. The purpose of this study was to investigate the effects of dyslipidemia on osteoclast differentiation associated with TLR2 and TLR4 in periodontal tissues using a rat dyslipidemia (apolipoprotein E deficient) model.

Methods

Levels of plasma OxLDL, and the cholesterol and phospholipid profiles in plasma lipoproteins were compared between apolipoprotein E-deficient rats (16-week-old males) and wild-type (control) rats. In the periodontal tissue, we evaluated the changes in TLR2, TLR4, receptor activator of nuclear factor kappa B ligand (RANKL) and tartrate resistant acid phosphatase (TRAP) expression.

Results

Apolipoprotein E-deficient rats showed higher plasma levels of OxLDL than control rats (p<0.05), with higher plasma levels of total cholesterol (p<0.05) and LDL-cholesterol (p<0.05) and lower plasma levels of high-density lipoprotein cholesterol (p<0.05). Their periodontal tissue also exhibited a higher ratio of RANKL-positive cells and a higher number of TRAP-positive osteoclasts than control rats (p<0.05). Furthermore, periodontal gene expression of TLR2, TLR4 and RANKL was higher in apolipoprotein E-deficient rats than in control rats (p<0.05).

Conclusion

These findings underscore the important role for TLR2 and TLR4 in mediating the osteoclast differentiation on alveolar bone response to dyslipidemia.

Potential association of paraoxonase-1, type 2 diabetes mellitus, and periodontitis

BACKGROUND

The association between periodontitis and systemic diseases, including cardiovascular diseases and diabetes mellitus (DM), has been recognized repeatedly. Paraoxonase-1 (PON-1) is involved in the prevention of atherosclerosis, and decreased enzyme activity in patients with DM has been shown. The aim of this study is to investigate a possible correlation between decreased PON-1 activity and the association between impaired glucose metabolism or DM and periodontitis.

METHODS

PON-1 phenotype distribution and enzyme activities were characterized by measuring the hydrolysis of phenylacetate and paraoxon in serum samples of 87 patients with type 2 DM and 46 patients with pre-DM showing impaired fasting plasma glucose and/or impaired oral glucose tolerance. The control group comprised 64 individuals with normal fasting plasma glucose and normal glucose tolerance. Altogether, 154 study participants were available for complete clinical periodontal examination.

RESULTS

No difference in periodontitis prevalence existed between the study groups. However, patients with DM had an increased risk of suffering from generalized periodontitis (adjusted odds ratio = 4.05; 95% confidence interval = 1.24 to 13.18; P = 0.02), and their PON-1 activity was reduced compared to controls. In contrast, patients with pre-DM showed neither an increased periodontitis risk nor an impaired paraoxonase status. PON-1 was not associated directly with periodontitis. Nevertheless, concerning patients with DM, poor oral hygiene, male sex, and PON-1 phenotype were found to be significant predictors for periodontitis extent.

CONCLUSIONS

Type 2 DM, but not a prediabetic state, increases the risk of generalized periodontitis. PON-1 status in patients with type 2 DM may contribute to this association.

Periodontal status and hyperlipidemia: statin users versus non-users

BACKGROUND

The association between serum lipids and periodontal disease has been studied predominantly in patients with chronic periodontitis with limited data available regarding periodontal status of patients with hyperlipidemia. Meanwhile, the impact of statins on the periodontal health of the population also remains largely underexplored. This study aims to assess the periodontal status among patients with hyperlipidemia and users of statins.

METHODS

In this cross-sectional study, 94 patients with hyperlipidemia (50 receiving statins and 44 receiving non-pharmacologic therapy) and 46 control individuals who were normolipidemic underwent periodontal examination (plaque index, gingival index [GI], probing depth [PD], and clinical attachment level [CAL]). Biochemical parameters measured included serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein cholesterol levels.

RESULTS

PD and GI were significantly higher in patients with hyperlipidemia who were non-statin users compared with the normolipidemic individuals (P <0.001 [PD] and P <0.05 [GI]) and the statin group (P = 0.001 [PD] and P <0.05 [GI]). Periodontal parameters between statin users and the normolipidemic group did not differ significantly. After adjusting for confounders, positive and significant correlations were observed between PD and TG, and TC and LDL, whereas CAL shared correlation with TC and LDL. GI was correlated with TG and TC. Regression analyses revealed that whereas TC was associated significantly with PD (P <0.001), LDL showed significant association with CAL (P = 0.013). TG showed significant association with GI (P = 0.020).

CONCLUSIONS

Our findings suggest that relative to the general population, patients with hyperlipidemia are more prone to periodontal disease. Also, within the limits of this study, statins have a positive impact on periodontal health.

Evaluation of periodontal status and effectiveness of non-surgical treatment in patients with type 2 diabetes mellitus in Taiwan for a 1-year period

BACKGROUND

The periodontal status and effects of non-surgical periodontal treatment in patients with type 2 diabetes mellitus and periodontal disease are assessed.

METHODS

One-hundred patients with type 2 diabetes (mean ± SD hemoglobin (Hb)A1c level: 7.3% ± 0.94%) and periodontal disease were recruited for this study. The group with moderate-to-severe periodontal disease included patients with >1 tooth with a probing depth (PD) ≥5 mm and >2 teeth with a clinical attachment loss (AL) ≥ 6mm, and the group with mild periodontal disease included patients with <1 affected tooth, and >2 affected with a clinical AL ≥ 6mm. Patients (28 patients in the mild group and 72 patients in the moderate-to-severe group) underwent non-surgical periodontal treatments. We analyzed differences in serum concentrations of metabolic parameters (glycated hemoglobin and low-density lipoprotein), inflammatory parameters (interleukin [IL]-1β and C-reactive protein [CRP]), and periodontal parameters between the two groups before treatment and at 3, 6, 9, and 12 months post-therapy.

RESULTS

Seventy-five patients with diabetes (21 patients in the mild group and 54 patients in the moderate-to-severe group) completed the study. Significant differences in the plaque index (PI), gingival index (GI), PD, and clinical AL at examination times were observed in the whole cohort (P <0.05). We observed significant differences in the PI, GI, and PD in the moderate-to-severe group (P <0.05), whereas there was only a significant difference in PD in the mild group (P <0.05) between baseline and 12 months post-treatment. Both groups experienced improved glycemic control, but the difference was insignificant. CRP and IL-1β levels were significantly different at examination times for the whole cohort (P <0.05). No significant positive association among metabolic and inflammatory parameters at 12 months post-therapy were found.

CONCLUSION

Non-surgical periodontal treatment improved and maintained the periodontal health of patients with well-controlled diabetes, but no significant reduction of metabolic parameters was observed over a 1-year period.

Association between metabolic syndrome and periodontal disease

BACKGROUND

Metabolic syndrome has been suggested as a potential risk factor for periodontal disease. Data based on NHANES III, with 7431 subjects aged 20 years or older, were analysed to confirm the association between metabolic syndrome and periodontal disease, and identify which components of metabolic syndrome might play a role in this association.

METHODS

Clinical criteria for metabolic syndrome included: (1) abdominal obesity; (2) increased triglycerides; (3) decreased HDL cholesterol; (4) hypertension or current use of hypertension medication; and (5) high fasting plasma glucose. Periodontal disease was evaluated by probing pocket depth (PPD) and was defined as mean PPD≥2.5 mm.

RESULTS

Women with two or more metabolic components had significantly increased odds of having periodontal disease as compared to those with no component [(two components, OR=5.6 (95% CI: 2.2-14.4); three or more, OR=4.7 (2.0-11.2)]. Using the definition of metabolic syndrome as having three to five metabolic components (reference group with <3 components), the adjusted odds ratios were 1.0 (0.7-1.6) for men and 2.1 (1.2-3.7) for women. Abdominal obesity was the largest contributory factor in both genders.

CONCLUSIONS

While the association between metabolic syndrome and periodontal disease was particularly significant for women, abdominal obesity appeared to be the contributing metabolic factor for both genders.

Association between periodontitis and impaired fasting glucose and diabetes

OBJECTIVE

Many studies have reported that periodontal disease is associated with diabetes, but its relation with impaired fasting glucose (IFG) has been understudied. This study investigated the relationship between chronic periodontitis, IFG, and diabetes in the U.S. population.

RESEARCH DESIGN AND METHODS

Participants in the National Health and Nutrition Examination Survey III, aged ≥ 20 years, who received periodontal examinations and provided blood samples (n = 12,254) were grouped into quintiles of mean clinical attachment loss (CAL) and pocket depth, with the lowest category being the reference. Plasma fasting glucose was categorized into three groups (normal, <100 mg/dL; IFG, ≥ 100 but <126 mg/dL; and diabetic, ≥ 126 mg/dL). Sociodemographic factors and other potential risk factors were obtained by interview or examination. SAS 9.1 was used for statistical analysis accounting for the complex weighted sampling.

RESULTS

Participants in the top quintile category of CAL had higher prevalence odds of IFG (odds ratio [OR] 1.55 [95% CI 1.16-2.07]) and diabetes (4.77 [2.69-8.46]) after adjustment for related confounders, compared with those in the bottom quintile. The highest quintile of pocket depth was positively associated with IFG (1.39 [1.00-1.92]) and diabetes (1.63 [1.10-2.42]) compared with the lowest quintile. ORs for CAL increased from the lowest to the highest quintile (P value test for trend <0.01) for all outcomes. The ORs for pocket depth also tended to rise across quintiles.

CONCLUSIONS

Chronic periodontitis measured by CAL and pocket depth was positively associated in a linear relation with IFG and diabetes in U.S. adults.

Short-term effects of periodontal therapy as an adjunct to anti-lipemic treatment

OBJECTIVE

This study was conducted to assess the effect of improved periodontal health following periodontal treatment on metabolic lipid control of patients on anti-lipemic treatment.

MATERIALS AND METHODS

The study population consisted of 20 patients aged 34-62 years with diagnoses of hyperlipidemia and chronic periodontitis. All patients used statin to treat their elevated levels of low-density lipoprotein cholesterol. Blood samples were obtained for measurement of serum lipids, fasting plasma glucose, and high sensitive C-reactive protein. Periodontal parameters, including plaque index, gingival index, probing pocket depth, clinical attachment level, and percentage of bleeding on probing, were evaluated. All parameters were assessed in each subject at baseline, after 3 months as a control (at the time of periodontal treatment), and 3 months after the non-surgical periodontal treatment that included scaling and root planning.

RESULTS

All lipid parameters decreased after the periodontal treatment, but only the decreases in total cholesterol and low-density lipoprotein cholesterol levels reached statistical significance compared to baseline (P = 0.002 and P = 0.003, respectively).

CONCLUSION

Improved periodontal health may influence metabolic control of hyperlipidemia and could be considered as an adjunct to the standard measures of hyperlipidemic patient care.

Possible involvement of advanced glycation end products in periodontal diseases

Periodontal diseases are considered as multifactorial conditions initiated by infection with pathogenic bacteria, promoted by inflammation and immune response against bacteria and modified by different environmental and genetic factors. Recently, interest in periodontal diseases has been increasing due to the awareness that the hyperinflammatory status associated with this disorder could impose a significant increase of reactive oxygen species (ROS) relevant to numerous systemic diseases driven by a pro-oxidant profile. A highly complex interplay occurs between oxidative stress and AGEs (Advanced Glycation End products), a group of heterogeneous compounds that form constantly under physiologic conditions, although their rate of formation is markedly increased in hyperglycemia and oxidizing conditions. Starting from the most relevant hypotheses on the pathogenesis of periodontal diseases, the present review outlines its relationship with oxidative stress and inflammation response in order to make a critical evaluation of the potential role of AGEs in periodontal deterioration. Although direct evidence for the presence of AGEs in the periodontal ligament is still lacking, valuable approaches based on the use of periodontal cells along with genetic and biochemical studies in animal models and chronic periodontal patients support a potential role for protein glycation in the aetiology and severity of this disease. Following a review of the current literature, the present study highlights the need for further investigation on the presence of AGEs in the periodontal ligament as a means for the comprehension of the pathogenic mechanisms underlying periodontal diseases in order to develop prevention and treatment modalities for this dysfunction.

Metabolic syndrome, periodontal infection, and dental caries

Only a few studies have examined the association of metabolic syndrome with periodontal infection and dental caries. The aim in this study was to examine the association of metabolic syndrome with periodontal infection and dental caries using the European Group for the Study of Insulin Resistance (EGIR) definition and its separate components. This study population consisted of dentate, non-diabetic individuals aged 30 to 64 years (N = 2050) who had never smoked. Relative risks (RR) were estimated with Poisson regression models. Metabolic syndrome was associated with teeth with deepened periodontal pockets 4 mm deep or deeper [adjusted RR 1.19 (95% CI 1.01-1.42)], with pockets 6 mm deep or deeper [adjusted RR 1.50 (95% CI 0.96-2.36)], and carious teeth [adjusted RR 1.25 (95% CI 0.93-1.70)]. The results suggest that metabolic syndrome or some of its components are associated weakly with periodontal infection.

Oxidized low-density lipoprotein increases interleukin-8 production in human gingival epithelial cell line Ca9-22

BACKGROUND AND OBJECTIVE

Recent epidemiological studies have shown a correlation between periodontitis and hyperlipidemia. We have found high levels of oxidized low-density lipoprotein (OxLDL) in the gingival crevicular fluid of dental patients. In the present study, we tried to examine the possible role of OxLDL in periodontal inflammation in vitro.

MATERIAL AND METHODS

Cells of the human gingival epithelial cell line Ca9-22 were cultured in media containing OxLDL, and the amounts of interleukin-8 (IL-8) and prostaglandin E(2) (PGE(2)) produced were measured using ELISAs.

RESULTS

Production of IL-8 by Ca9-22 cells was significantly increased when the cells were treated with OxLDL, but not with native LDL or acetylated LDL. Production of PGE(2) by Ca9-22 cells was enhanced by co-incubation with OxLDL and interleukin-1 beta (IL-1 beta). Scavenger receptor inhibitors, fucoidan and dextran sulfate, inhibited the OxLDL-induced IL-8 and PGE(2) production in the presence of IL-1 beta. The p(38) MAPK inhibitors SB203580 and SB202190 and the ERK inhibitor PD98059 inhibited the OxLDL-induced IL-8 production. Among oxidized lipids and chemically modified LDL, 7-ketocholesterol enhanced IL-8 production.

CONCLUSION

This is the first report to show that OxLDL enhances IL-8 production in epithelial cells.

Association between periodontal disease and metabolic syndrome

OBJECTIVES

Metabolic syndrome is a complex medical disorder characterized by visceral fat-type obesity involving hypertension, and abnormal glucose and lipid metabolism. The objective of this study was to investigate the relationship between periodontal disease and components of metabolic syndrome (obesity, lipid abnormality, hypertension, and hyperglycemia) in industrial workers of a single company in Tokyo, Japan.

METHODS

The study subjects consisted of 2478 adult employees (2028 men and 450 women; mean age: 43.3 years). The association between the presence of periodontal pockets and components of metabolic syndrome was investigated cross-sectionally using multiple logistic regression analysis, odds ratios (ORs), and 95 percent confidence intervals (CIs).

RESULTS

Body mass index, blood pressure, triglycerides, fasting blood glucose, and hemoglobin A1c (HbA1c) were significantly elevated (P < 0.05) in patients with periodontal pockets of 4 mm or more. We found that the OR of the presence of periodontal pockets adjusted for age, gender, and smoking habit was 1.8 (96 percent CI = 1.4-2.3) when the subjects with two positive components and without positive component were compared. And it was 2.4 (96 percent CI = 1.7-2.7) when the subjects with three or four positive components and without positive component were compared.

CONCLUSIONS

Our findings suggest an association between periodontal disease and metabolic syndrome in Japanese workers between the ages of 20 and 60 years.

Dual effect of statin medication on the periodontium

AIM

The aim of this study was to investigate the association between statin medication and periodontal infection in an adult population.

MATERIAL AND METHODS

The study was based on a subpopulation of the Health 2000 Survey, which included dentate non-diabetic, non-rheumatic subjects who did not smoke, aged 40-69 years (n=2032). The main outcome variable was the number of teeth with periodontal pockets of 4 mm or more. Statin medication was categorized in two ways: firstly, subjects with statin medication of some sort (n=134) versus those with none, and secondly, subjects taking either simvastatin (n=58), atorvastatin (n=38), some other statin (n=38) or no statin medication. Relative risks (RR) were estimated using negative binomial and Poisson regression models.

RESULTS

We found a weak negative association between statin medication and periodontal infection among subjects with dental plaque or gingival bleeding. Among subjects with no gingival bleeding, statin medication was found to be associated with an increased likelihood of having deepened periodontal pockets.

CONCLUSION

Statin medication appears to have an effect on the periodontium that is dependent on the inflammatory condition of the periodontium. More evidence is needed to achieve a comprehensive understanding of the effects of statins.

Pro-inflammatory biomarkers during experimental gingivitis in patients with type 1 diabetes mellitus: a proof-of-concept study

AIM

To compare gingival crevicular fluid (GCF) biomarker levels and microbial distribution in plaque biofilm (SP) samples for subjects with type 1 diabetes (T1DM) versus healthy subjects without diabetes during experimental gingivitis (EG).

MATERIALS AND METHODS

A total of nine T1DM patients and nine healthy controls of age and gender similar to the T1DM patients were monitored for 35 days during EG. Hygiene practices were stopped for 3 weeks, and GCF, SP, plaque index (PI) and gingival index were determined. IL-1beta, IL-8, MMP-8 and MMP-9 were quantified by enzyme-linked immunosorbent assay, and SP samples were assessed by DNA-DNA hybridization for a panel of 40 subgingival microbial species.

RESULTS

IL-1beta levels in T1DM patients were elevated compared with healthy individuals, and showed differences between groups at 7-21 days while healthy patients showed IL-1beta increases from baseline to 14-21 days (p<0.05). Differences were observed in MMP-9 levels between patients with and without T1DM at 7-14 days (p<0.05). Orange complex species and PI measurements displayed a superior correlation with biomarker levels when compared with other complexes or clinical measurements during EG.

CONCLUSIONS

The mean GCF biomarker levels for IL-1beta and MMP-8 were most significantly elevated in T1DM subjects compared with healthy individuals during EG, not resulting from differences in the mean PI or microbial composition.