Diabetes modulates gene expression in the gingival tissues of patients with chronic periodontitis

AIM: This study evaluated whether diabetes modulates gene expression [interleukin (IL)-1beta, IL-1ra, IL-6, IL-8, IL-10; tumor necrosis factor (TNF)-alpha; interferon (IFN)-gamma, receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin (OPG)] in sites with periodontitis. MATERIALS AND METHODS: Gingival biopsies were harvested and divided into three groups--Control group: systemically and periodontally healthy subjects (n = 10); Periodontitis group: systemically healthy subjects diagnosed with chronic periodontitis (n = 20); Diabetes group: type 1 diabetic subjects, diagnosed with chronic periodontitis (n = 20). Total RNA was obtained and analyzed by quantitative polymerase chain reaction. RESULTS: Data analysis demonstrated that, except for OPG, mRNA levels for all factors were increased by inflammation (P < 0.001). Interleukin-1beta, IL-1ra, IL-6, IL-8, IFN-gamma, and RANKL mRNA levels were higher in the diabetic group when compared with the control non-periodontitis group (P < 0.05), whereas IL-10 and OPG were lower (P < 0.05). No difference was observed for TNF-alpha between diabetic and control groups (P > 0.05). Diabetes lowered IL-1beta, IL-8, IL-10, TNF-alpha, RANKL, and OPG mRNA levels in sites with comparable type of periodontitis (P < 0.001). Moreover, increased RANKL:OPG and IL-6:IL-10 ratios were found. CONCLUSION AND CLINICAL RELEVANCE: Taken together, these data suggest that decreased levels of IL-10 and OPG may play an important role in the periodontal breakdown in diabetic patients.     

Interleukin-17 and interleukin-18 levels in saliva and plasma of patients with chronic periodontitis

Özçaka Ö, Nalbantsoy A, Buduneli N. Interleukin‐17 and interleukin‐18 levels in saliva and plasma of patients with chronic periodontitis. J Periodont Res 2011; 46: 592–598. © 2011 John Wiley & Sons A/S Background and Objective: This study was planned to investigate whether patients with chronic periodontitis exhibit different salivary and/or plasma concentrations of interleukin (IL)‐17 and IL‐18 compared with clinically healthy subjects. Material and Methods: Whole saliva and blood samples, together with full‐mouth clinical periodontal recordings, were obtained from 22 otherwise healthy untreated nonsmokers with chronic periodontitis and from 21 systemically and periodontally healthy control subjects. The concentrations of IL‐17 and IL‐18 in saliva and plasma were determined using ELISAs. Results: The healthy control group exhibited significantly lower values in all clinical periodontal measurements (p < 0.001). The salivary concentration of IL‐17 was significantly lower, and that of IL‐18 significantly higher, in patients from the chronic periodontitis group compared with healthy control subjects (p = 0.025 and p = 0.009, respectively). Plasma IL‐17 and IL‐18 concentrations were similar in the two study groups (p > 0.05). Conclusion: Within the limits of the present study, it may be suggested that an elevated salivary IL‐18 level in untreated nonsmoker chronic periodontitis patients has the potential to be a biomarker for periodontal tissue destruction.     

不同牙周健康状况者血清白细胞介素21的检测水平

目的:初步探讨白细胞介素21(interleukine 21,IL-21)与牙周健康状况的关系.方法:选择符合纳入标准的受试者105 名,其中无牙周炎组、轻度、中度及重度牙周炎组分别为17 人(16.2%),17 人(16.2%),24 人(22.9%),47 人(44.8%).牙周检查包括:牙周探诊深度(probing depth, PD),牙周附着丧失(attachment loss, AL),龈沟出血指数(sulcus bleeding index, SBI),菌斑指数(plaque index, PLI),采用双抗体夹心酶联免疫吸附试验(ELISA)检测受试者血清IL-21水平.结果:无牙周炎组、轻度、中度及重度牙周炎组血清IL-21水平(pg/ml)分别为143.23、202.93、222.21、239.95,"牙周炎组"(227.96±146.39)与"非牙周炎组"(143.23±70.18)之间IL-21水平的差异有显著性(t=2.33,P=0.022).IL-21水平与牙周检查指标(PD、AL、BI、PLI)之间均有显著正相关关系(P<0.05), IL-21水平与全口PD≥5 mm且AL≥4 mm的牙齿所占的比例之间也有显著正相关关系(P=0.036).结论:血清IL-21水平与牙周病严重程度呈正相关,牙周炎患者血清IL-21水平显著升高.     

Probing site configuration in patients with untreated periodontitis

This study examined the morphology of 487 probing sites in patients with untreated periodontitis, using a constant force probe (0.25 N, 0.5 mm) and flexible stent with guide grooves, at 3 adjacent points per site, 6 sites per tooth. Sites were classified into 9 configuration types according to the relationship of the 3 adjacent points. Duplicate measurements were made and sites were analysed with special reference to whether a slight horizontal movement was likely at the second examination. 60% of individual point probing measurements were exactly reproduced, but only 23% of site configurations. 65% of configuration change was accountable on the basis of slight horizontal shift of the probe. Only 13% of configurations required the postulate of other forms of probing error. These results suggest that probing reproducibility is not always an indication of site reproducibility, and that the variation of probe position in the transverse plane is an important source of probing error, even when a stent is used.     

Association of interleukin-10 gene promoter polymorphisms with chronic and aggressive periodontitis

Oral Diseases (2012) 18 , 271–279 Objective: Interleukin‐10 gene promoter polymorphisms have been associated with interleukin‐10 decreased production, thereby playing a role in the pathogenesis of periodontitis. This study aimed to investigate whether interleukin‐10 single nucleotide polymorphisms at positions ‐1087(G/A) and ‐597(C/A) are associated with generalised chronic periodontitis and localised aggressive periodontitis. Methods: Genomic DNA samples were isolated from 276 unrelated Jordanian participants. Subjects were categorised into 86 periodontally healthy controls, 105 chronic periodontitis patients and 85 localised aggressive periodontitis patients. Genotype frequencies were calculated, and differences were determined using Pearson chi‐squared test, and odds ratio and 95 % confidence intervals were included. Results: The frequencies of the ‐1087A and ‐597A alleles were significantly more common in chronic periodontitis patients than controls. The A‐positive allele genotypes (GA, AA) at position ‐1087 and A‐positive allele genotypes (CA, AA) at position ‐597 appeared to increase the risk of having chronic periodontitis. No significant differences were observed in the genotype frequencies between localised aggressive periodontitis patients and controls. Conclusions: These findings indicate the possible use of interleukin‐10 single nucleotide polymorphisms as genetic markers in chronic periodontitis patients and further emphasise the molecular differences between chronic periodontitis and aggressive periodontitis.     

Smoking modulates interferon-gamma expression in the gingival tissue of patients with chronic periodontitis

Although interferon-gamma (IFN-gamma) plays a critical role in periodontitis, no information is available regarding the effect of smoking on this cytokine in the periodontium. Therefore, this study aimed to evaluate the effect of smoking on the IFN-gamma levels in gingival tissue from patients with chronic periodontitis. Sixty-two patients were assigned to three groups: healthy [non-smoking and periodontally healthy individuals (probing depth or= 5 mm and bleeding on probing; n = 25)]; and smoking [smokers (>or= 1 pack/day for at least 10 yr) diagnosed with chronic periodontitis (n = 25)]. Gingival biopsies were analyzed by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. Regardless of smoking status, diseased patients presented higher levels of IFN-gamma than peridontally healthy patients. In sites with comparable types of periodontitis, smoking increased both protein and mRNA levels of IFN-gamma in gingival tissue. Within the limits of this study, it can be concluded that modulation of periodontal tissue destruction by smoking may involve its effect on IFN-gamma production.     

Microbiological profile of untreated subjects with localized aggressive periodontitis

Aim: The microbial profile of localized aggressive periodontitis (LAgP) has not yet been determined. Therefore, the aim of this study was to evaluate the subgingival microbial composition of LAgP.
Material and Methods: One hundred and twenty subjects with LAgP ( n =15), generalized aggressive periodontitis (GAgP, n =25), chronic periodontitis (ChP, n =30) or periodontal health (PH, n =50) underwent clinical and microbiological assessment. Nine subgingival plaque samples were collected from each subject and analysed for their content of 38 bacterial species using checkerboard DNA–DNA hybridization.
Results: Red complex and some orange complex species are the most numerous and prevalent periodontal pathogens in LAgP. The proportions of Aggregatibacter actinomycetemcomitans were elevated in shallow and intermediate pockets of LAgP subjects in comparison with those with GAgP or ChP, but not in deep sites. This species also showed a negative correlation with age and with the proportions of red complex pathogens. The host-compatible Actinomyces species were reduced in LAgP.
Conclusion: A. actinomycetemcomitans seems to be associated with the onset of LAgP, and Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Campylobacter gracilis, Eubacterium nodatum and Prevotella intermedia play an important role in disease progression. Successful treatment of LAgP would involve a reduction in these pathogens and an increase in the Actinomyces species.     

Tooth loss in well-maintained patients with chronic periodontitis during long-term supportive therapy in Brazil

AIM: The objective of this retrospective study was to assess the reasons for tooth loss in a sample of patients who underwent periodontal therapy and supportive periodontal therapy (SPT) in a Brazilian private periodontal practice. MATERIAL AND METHODS: A sample of 120 subjects who had been treated and maintained for 10 years or longer was selected from patients attending a periodontal practice. All patients followed a similar treatment: basic procedures, re-evaluation and periodontal surgery where indicated. Reasons for tooth loss were categorized as periodontal, caries, endodontal, root fractures and extraction of retained or partially erupted third molars. RESULTS: Of the 2927 teeth present at the completion of active periodontal treatment, 53 (1.8%) were lost due to periodontal disease, 16 (0.5%) for root fracture, six (0.2%) to caries, five (0.2%) for endodontic reasons and 31 (1.0%) were lost to extraction of retained or partially erupted third molars. Logistic regression analysis was performed to investigate the association between five independent variables with tooth loss due to periodontitis. Only age (> 60 years) and smoking were statistically significant (p < 0.05). CONCLUSION: The findings of this survey were consistent with previous studies. Older subjects and smokers were more susceptible to periodontal tooth loss. In addition, patients with generalized chronic periodontitis were treated and maintained for long-term periods with low rates of tooth loss.     

A trend of increase in periodontal interleukin-6 expression across patients with neither diabetes nor periodontal disease, patients with periodontal disease alone, and patients with both diseases

Background and Objective: Epidemiological studies have established that patients with diabetes have increased prevalence and severity of periodontal disease. However, the periodontal expression of inflammatory cytokines and matrix metalloproteinases (MMPs) in diabetic patients has not been well characterized. The objective of this study was to determine the difference in the periodontal expression of MMP‐1, MMP‐8, interleukin‐6, tumor necrosis factor‐α and interleukin‐1β between diabetic and nondiabetic patients. Material and Methods: Periodontal tissue specimens were collected from nine nondiabetic patients without periodontal disease (group 1), from 11 nondiabetic patients with periodontal disease (group 2) and from seven diabetic patients with periodontal disease (group 3). The expression of MMP‐1, MMP‐8, interleukin‐6, tumor necrosis factor‐α and interleukin‐1β was quantified using real‐time polymerase chain reaction. Results: The nonparametric Kruskal–Wallis test showed that the difference in interleukin‐6 expression among the groups was statistically significant (p = 0.04). Furthermore, the generalized Kruskal–Wallis nonparametric linear‐by‐linear association test showed a statistically significant trend of increase in the expression of interleukin‐6 from group 1 to group 2 to group 3 (p = 0.02) and a suggestion of such a trend for MMP‐1 (p = 0.05). No increase in MMP‐8 expression was observed in patients in group 3 compared to patients in groups 1 and 2. Although the average expression levels of MMP‐1, interleukin‐1β and tumor necrosis factor‐α were increased from group 1 to group 3, the differences were not statistically significant. Conclusion: A trend of increased interleukin‐6 expression in periodontal tissues was observed across patients with neither diabetes nor periodontal disease, patients with periodontal disease alone, and patients with both diseases.     

Gene polymorphisms of tissue plasminogen activator and plasminogen activator inhibitor-1 in Turkish patients with generalized aggressive periodontitis

AIM: Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) have important roles in proteolytic events in periodontitis. The aim of this study was to investigate TPA and PAI-1 gene polymorphisms in relation to susceptibility to generalized aggressive periodontitis (G-AgP). METHODS: Genomic DNA was obtained from peripheral blood of 90 G-AgP patients and 154 periodontally healthy subjects. 4G/5G polymorphism in the promoter region of the PAI-1 gene and Alu-repeat insertion/deletion (I/D) polymorphism in intron 8 of the TPA gene were genotyped by polymerase chain reaction and endonuclease digestion. RESULTS: The genotype distributions of TPA and PAI-1 genes were similar between G-AgP and healthy subjects (p>0.05). The distribution of TPA genotypes in G-AgP patients was 33.4% D/D, 44.4% I/D, and 22.2% I/I and was 26.3% D/D, 40.4% I/D, and 33.3% I/I in healthy subjects. The D allele was 55.6% in G-AgP and 46.6% in healthy subjects. There was a significant difference among study groups in D allele frequencies (p=0.044). The PAI-1 genotype distribution in G-AgP was 29.1% 4G/4G, 43.0% 4G/5G, and 27.9% 5G/5G, while it was 35.7% 4G/4G, 43.8% 4G/5G, and 20.5% 5G/5G in healthy subjects. CONCLUSION: These data suggest that the D polymorphic allele of TPA gene polymorphism could be associated with susceptibility to G-AgP in Turkish subjects.     

Flow-cytometric analysis of lymphocyte subsets in patients with advanced periodontitis

Peripheral blood lymphocytes from 36 patients with advanced periodontitis and from 34 healthy subjects were examined using a panel of monoclonal antibodies and fluorescence flow cytometry. The absolute and relative counts of B-cells, T-cells, T-helper (TH), T-suppressor/cytotoxic (TS) cells, activated T-cells and natural killer cells were assessed and the TH/S ratio was calculated. In the periodontitis patients, the TH/S ratio was 1.56 +/- 0.62 and in the controls 1.35 +/- 0.55. This was not statistically significant. A classification on the basis of sex also did not show significant differences in the TH/S ratio. B-cells and activated T-cells were slightly increased in the periodontitis group. However, all determined lymphocyte subpopulations revealed no significant differences between the groups. These results indicate that local inflammatory reactions and immunoregulatory dysfunction are limited to the periodontium in the patients with advanced periodontitis, with no significant quantitative effects on the peripheral lymphocyte subpopulations.     

Prevalence of Peptostreptococcus micros morphotypes in patients with adult periodontitis

The prevalence of the smooth and rough colonial morphotypes of Peptostreptococcus micros was examined with culture technique in 123 patients with adult periodontitis (age 24–68 years). Of all subgingival samples, 91% contained the smooth morphotype of P. micros. The smooth morphotype constituted a mean percentage of the total anaerobic viable biota of 6.0%, with a range of 0.02–35.7%o. Of these samples, 49%> contained colonies of the rough morphotype as well, with a mean percentage of the total anaerobic viable biota of 2.3%> (range 0.01–16.2%i). None of the samples contained only the rough morphotype. The total percentage of P. micros varied from 0.02–35.71%> with a mean of 7.2%>. No correlation was found between the prevalence of both morphotypes of P. micros and the age of the subjects or with loss of attachment or pocket depth.     

TLR2 Arg753Gly, TLR4 Asp299Gly and Thr399Ile gene polymorphisms are not associated with chronic periodontitis in a Turkish population

AIM: Toll-like receptor (TLR) gene polymorphisms could affect the host's ability to respond to microbial pathogens. In this case-control study, the association of TLR2 and TLR4 gene polymorphisms with chronic periodontitis (CP) was investigated. MATERIALS AND METHODS: Genomic DNA was obtained from the peripheral blood of 83 patients with CP and 106 periodontally healthy subjects. The TLR2 Arg753Gly, Arg677Trp and TLR4 Asp299Gly, Thr399Ile gene polymorphisms were genotyped by the polymerase chain reaction-restriction fragment length polymorphism method. The data were analysed by a chi2 test, logistic regression analysis and the Mann-Whitney U test. RESULTS: The 753Gln allele was found in 6.1% of the CP patients as compared with 6.6% in the control group (p>0.05). The frequency of the 299Gly and 399Ile allele was 2.4% and 1.8% in CP patients. For the healthy subjects, the frequency was 2.8% for the 299Gly and 2.5% for the 399Ile allele (p>0.05). None of the CP patients or healthy subjects showed homozygosity for the TLR2 and TLR4 alleles. Percentage of sites with bleeding on probing and plaque were significantly higher in 299Gly-positive patients compared with 299Gly-negative patients (p<0.05). CONCLUSION: These results showed that the TLR2 and TLR4 gene polymorphisms studied are not associated with susceptibility to CP in Turkish patients.     

Prevalence of periodontal pathogens in Brazilians with aggressive or chronic periodontitis

OBJECTIVES: Previous studies suggest differences between geographically and racially distinct populations in the prevalence of periodontopathic bacteria as well as greater periodontal destruction associated with infection by highly leucotoxic Actinobacillus actinomycetemcomitans. The present study examined these hypotheses in Brazilians with aggressive or chronic periodontitis. MATERIALS AND METHODS: Clinical, radiographical, and microbiological assessments were performed on 25 aggressive periodontitis and 178 chronic periodontitis patients including 71 males and 132 females, 15-69 years of age. RESULTS: The prevalence of Porphyromonas gingivalis was similar to that of other South American populations. The prevalence of A. actinomycetemcomitans and its highly leucotoxic subgroup was higher in Brazilians. Highly leucotoxic A. actinomycetemcomitans was more prevalent in aggressive periodontitis (chi2=27.83) and positively associated with deep pockets (>6 mm, chi2=18.26) and young age (<29 years, chi2=18.68). Greater mean attachment loss was found in subjects with highly leucotoxic A. actinomycetemcomitans than in subjects with minimally leucotoxic (p=0.0029) or subjects not infected (p=0.0001). CONCLUSION: These data support the hypothesis of differences between populations in the prevalence of periodontopathic bacteria and of greater attachment loss in sites infected with highly leucotoxic A. actinomycetemcomitans. Detection of highly leucotoxic A. actinomycetemcomitans in children and adolescents may be a useful marker for aggressive periodontitis.