Insulin resistance and periodontal disease: an epidemiologic overview of research needs and future directions

Frequency of putative periodontal pathogens among type 1 diabetes mellitus: a case-control study

Objective

The aim of the present study is to compare and assess the risk of periodontitis due to the presence of four putative periodontopathic bacteria viz., Eikenella corrodens, Campylobacter rectus, Prevotella intermedia and Prevotella nigrescens. To fulfil the above objective, polymerase Chain reaction using the primers targeting 16S rRNA gene of the bacterial species was performed with the subgingival plaque collected from the permanent first molars of type 1 diabetic children and age matched healthy children.

Results

The prevalence of periodontal pathogens in diabetic and healthy children was 6% and 16% for E. corrodens, 18% and 36% for C. rectus, 2% and 2% for P. intermedia, 4% and 0%, for P. nigrescens respectively. Statistically, significant difference was not observed for the prevalence of all the four periodontal pathogens between type 1 diabetic and healthy children (P = 1.00). The results of the present study thus reveal a negative correlation of type I diabetes to periodontitis in association to Eikenella corrodens, Campylobacter rectus, Prevotella intermedia and Prevotella nigrescens.

Does Treatment of Periodontal Disease Influence Systemic Disease?

Periodontal diseases are the most common human diseases globally, with gingivitis affecting up to 90% and periodontitis affecting 50% of adults. Tooth enamel is the only nonshedding tissue in the human body. In the absence of proper oral hygiene measures, microbial biofilm (dental plaque) develops on the teeth to include more than 700 different bacterial species, along with viruses, fungi, archea, and parasites. With time, ecological imbalances promote the growth of selected commensal species that induce host inflammatory pathways resulting in tissue destruction, including ulceration of the periodontal epithelium.

Periodontal disease and type I diabetes mellitus: Associations with glycemic control and complications

OBJECTIVE

The aim of the study was to evaluate periodontal health status in patients diagnosed with type 1 diabetes mellitus (DM1) and to establish a correlation between metabolic control and periodontal health status.

MATERIALS AND METHODS

Periodontal health parameters namely plaque index (PI), gingival index (GI), probing pocket depth (PPD) and clinical attachment loss (CAL) were recorded in 28 patients diagnosed with type 1 diabetes mellitus (DM1) and 20 healthy controls. Diabetes history was recorded based on the information provided by the physician and it included date of diagnosis, duration, age of diagnosis, latest values of glycosylated haemoglobin and existing diabetic complications. Statistical analysis was performed to evaluate the relationship between periodontal parameters and degree of metabolic control, the duration of the disease and the appearance of complications.

RESULTS

The periodontal health in the diabetic group was compromised and they had greater bleeding index (P < 0.001), probing pocket depth (P < 0.001) and clinical attachment level (P = 0.001). Patients diagnosed for diabetes for shorter duration of time (4-7 years) showed bleeding index-disease severity correlation to be 1.760 ± 0.434.

CONCLUSION

Periodontal disease was more evident in type 1 diabetes mellitus patients and periodontal inflammation is greatly increased in subjects with longer disease course, poor metabolic control and diabetic complications.

The effect of full-mouth tooth extraction on glycemic control among patients with type 2 diabetes requiring extraction of all remaining teeth: a randomized clinical trial

BACKGROUND AND OBJECTIVE

Several studies have shown that periodontitis can complicate the severity of diabetes by worsening the degree of glycemic control. The purpose of this study was to determine the effect of full-mouth tooth extraction on glycemic control among type 2 diabetic patients.

MATERIAL AND METHODS

A total of 58 patients with type 2 diabetes mellitus and advanced periodontitis who were requiring extraction of all remaining teeth were randomized consecutively into treatment (full-mouth tooth extraction) and control groups (no treatment). Eight patients were lost to follow-up or reported use of antibiotics, leaving 50 patients to be included in the analysis. All patients had all their remaining teeth in a hopeless condition. Relevant data were collected, and glycosylated hemoglobin (HbA(1c) ) and fasting blood glucose levels were measured at baseline and at follow-up times of 3 and 6 mo.

RESULTS

At baseline, the mean (SD) HbA(1c) level was 8.6% (1.24) in the treatment group and 7.7% (0.87) in the control group. In the treatment group, the mean HbA(1c) level decreased significantly from 8.6% at baseline to 7.4% after 3 mo of denture treatment, and continued to decrease to 7.3% after 6 mo. In the control group, the mean HbA(1c) decreased from 7.7% at baseline to 7.5% after 3 mo, and remained almost the same after 6 mo. After adjusting for the baseline HbA(1c) , the mean reduction in HbA(1c) after 3 mo in the treatment group [1.23% (0.79)] was significantly higher than the mean reduction in the control group [0.28% (0.87)].

CONCLUSION

Full-mouth tooth extraction resulted in an improvement in glycemic control among diabetic patients. Large-scale multicentre clinical trials are needed to confirm the current evidence.

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.

Effects of gender on serum biomarkers of systemic inflammation coincident to experimentally-induced periapical lesions

OBJECTIVE

The literature suggests that females have less adverse effects to infection than males, due to the protective effects of oestrogen. The purpose of our study is to compare the systemic effects of induced periapical lesions between groups of animals with various serum concentrations of oestrogen.

METHODS

To induce periapical inflammation, two molar tooth pulps were exposed in ovariectomized (OVX) and normal female (F) and castrated (Cast-M) and normal male (M) Sprague-Dawley rats (Experimental group, E). Sham-operated control animals from each group were also studied (Control group, C). Twenty-eight days later, serum and maxillas were collected. Serum 17β-oestradiol, testosterone, MMP-9, IL-18, IL-6, TNF-α, and IL-1β concentrations were measured by ELISA. Maxillas were cleaned of residual tissue and digital radiographs were made to verify the presence of periapical lesions. Data were compared by factorial ANOVA, post hoc Tukey, and Pearson correlation tests. Groups were considered to be significantly different when p<0.05.

RESULTS

The serum concentration of IL-18, TNF-α, IL-1-β, IL-6 and MMP-9 was greatest in OVX-E animals, compared to all other groups (p<0.001). F-E rats had significantly higher serum concentrations of these cytokines, compared to F-C. The fold difference in serum concentration of the biomarkers (between E and C groups) was significantly greater in females than males, even though males had higher baseline concentrations of all these biomarkers.

CONCLUSION

When females are oestrogen-deficient, their systemic response to periapical lesions is significantly greater than males, suggesting that oestrogen is essential in protecting females from the effects of this type of inflammation.

Cross-sectional study of periodontal care and Glycosylated Hemoglobin in an insured population

OBJECTIVE

Compare GHb among people with diabetes who have and have not received periodontal care.

RESEARCH DESIGN AND METHODS

This cross-sectional study linked 5 years of electronic medical record and dental insurance data for dually insured patients with diabetes, ages 40-70 years (n = 5,103). We assessed the association between annual mean GHb (%) and periodontal care (a proxy for periodontitis) defined using claim codes. Among patients who received periodontal care, we assessed the association between GHb and periodontal treatment intensity. We determined associations using linear regression adjusted for potential confounders and tested for effect modification by age, sex, insulin use, diabetes severity, BMI, and smoking.

RESULTS

Mean GHb was 7.66%; 38% of participants received periodontal care during the 5 years. After multivariate adjustment, patients who received periodontal care had a GHb level 0.08 percentage points higher than patients who did not (P = 0.02). In stratified analyses, the association was present for women (0.18 percentage points higher GHb with periodontal care, P < 0.001) but not significant for men (0.008 percentage points lower, P = 0.86). In patients who received periodontal care, those with one, and with two or more, surgical treatments had GHb 0.25 (P = 0.04) and 0.36 (P = 0.002) percentage points lower, respectively, than patients without periodontal surgeries.

CONCLUSIONS

This population-based cross-sectional study showed small associations between periodontal care (a proxy for periodontitis) and higher GHb. Well-controlled longitudinal studies or clinical trials are needed to evaluate causality and temporal trends. Sub-analyses suggest that further investigation of this association among women, and by intensity of periodontal treatment, may be of interest.

Smoking prevalence among dentists in Hyogo, Japan 2003

We examined smoking prevalence among dentists in Hyogo, Japan, as smoking would influence their smoking cessation interventions to encourage their patients to stop smoking. In 2003, a self-administered questionnaire was mailed to all members of the Hyogo Dental Association (HDA) in Japan. Of the 1,133 members of the HDA, 327 were current smokers (28.9%). Smoking prevalence among HDA members was significantly higher than that among Japan Medical Association (JMA) members in 2004, as previously reported (16.2%) (p<0.01). Although smoking prevalence among HDA members decreased overall in 2003 in comparison with 2000, smoking prevalence among dentists aged 20-39 yr increased. These findings indicate that smoking was more prevalent among dentists in Hyogo Prefecture than among Japanese medical doctors. It is important to promote smoking cessation among Japanese dentists so that dentists will be more likely to encourage their patients to quit smoking.

The Short-Term Effects of Treatment of Chronic Periodontitis on Circulating Levels of Endotoxin, C-Reactive Protein, Tumor Necrosis Factor-α, and Interleukin-6

BACKGROUND

The acute-phase response involves molecules including tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and C-reactive protein (CRP). This study aimed to determine whether subgingival scaling resulted in rapid changes in plasma concentrations of these molecules.

METHODS

Twenty-three non-smoking adults with chronic periodontitis received subgingival scaling for 60 minutes. Venous blood samples were taken at 0, 15, 30, 60, and 120 minutes. TNF-alpha and IL-6 were assayed from all samples and CRP from the baseline and final samples. Lipopolysaccharide (LPS) was assayed at 0, 15, and 30 minutes using limulus lysate assay (LAL) and EndoCAb Ig assays.

RESULTS

LPS assays were suggestive of a transient low-grade bacteremia, but changes in LPS approaching significance (P=0.061) were seen with LAL only. There was a significant increase in circulating TNF-alpha (P=0.0387) and IL-6 (P<0.0001), and the degree of change in TNF-alpha was correlated with the severity of periodontal breakdown (P=0.001). There was also a significant correlation between levels of IL-6 and TNF-alpha (P<0.001).

CONCLUSIONS

Chronic periodontitis patients undergoing an episode of subgingival scaling show a significant elevation in circulating TNF-alpha and IL-6. This may account for anecdotal reports of pyrexia following treatment and may be significant in terms of the relationship between periodontal disease, bacteremia, and cardiovascular disease.

Association between periodontal disease and left ventricle mass in essential hypertension

Chronic periodontitis has been associated with an increased risk for cardiovascular disease. Left ventricular mass is an established independent predictor of cardiovascular disease. In the present cross-sectional study, we tested the association between periodontitis and left ventricular mass in subjects with essential hypertension. One hundred four untreated subjects with essential hypertension underwent clinical examinations, including echocardiographic study, laboratory tests, and assessment of periodontal status according to the community periodontal index of treatment needs (CPITN). With increasing severity of periodontitis, there was a progressive increase in left ventricle mass. Mean values (g/height2.7) were 39.0 (+/-2.7) in CPITN 0 (periodontal health), 40.2 (+/-6.4) in CPITN 1 (gingival bleeding), 42.7 (+/-6.8) in CPITN 2 (calculus), 51.4 (+/-11.7) in CPITN 3 (pockets 4 to 5 mm), and 76.7 (+/-11.3) in CPITN 4 (pockets > or =6 mm) (overall F 51.2; P<0.0001). Body surface area (P=0.04), systolic (P<0.0001) and diastolic (P<0.01) blood pressure, and left ventricular mass (P<0.0001) were determinants of a composite of CPITN 3 and 4. In a multivariate logistic analysis, left ventricular mass was the sole determinant (P<0.0001) of CPITN stages 3 and 4. Our findings suggest a direct association between severity of periodontitis and left ventricular mass in subjects with essential hypertension. Periodontal evaluation might contribute to refine cardiovascular risk assessment in hypertensive subjects.