Influence of Periodontal Clinical Status on Salivary Levels of Glutathione Reductase.

BACKGROUND: Inadequate antioxidant balance may play a role in the excessive tissue breakdown in periodontitis. Because aggressive periodontitis (AgP) not only differs from chronic periodontitis (CP) in terms of clinical manifestations, this study investigates whether the salivary levels of glutathione reductase (GR) may be linked with periodontal status. METHODS: Saliva samples from patients with CP (n = 121), patients with AgP (n = 18), and healthy controls (n = 69) were collected. Periodontal status was assessed by criteria based on probing depth, clinical attachment level, and extent and severity of periodontal breakdown. GR salivary levels were analyzed by spectrophotometry. The association among GR concentration and CP or AgP was analyzed individually and adjusted for confounding using multivariate binary logistic regression models. RESULTS: GR levels not only differed significantly between the two periodontitis groups, being significantly greater in patients with AgP, but also were significantly greater than those observed in healthy controls. Synchronously, positive significant correlations between salivary GR concentration and clinical parameters were observed. After binary logistic regression analysis, both GR salivary levels ≥15.38 and ≥24.20 mU/mL were associated independently with CP and AgP, respectively. A significant interaction effect was also detected between increased GR salivary concentration and aging in the CP group. CONCLUSIONS: Increased GR salivary concentration may be a strong/independent prognostic indicator of the amount and extent of oxidative stress-induced periodontal damage in both CP and AgP. Likewise, saliva samples might reflect an interactive effect of GR levels associated with the aging-related cumulative characteristics of periodontal damage in CP.

Local and serum levels of adipokines in patients with obesity after periodontal therapy: one-year follow-up.

AIM: This study evaluated the effects of scaling and root planing (SRP) on gingival crevicular fluid (GCF) and serum levels of adipokines in patients with chronic periodontitis (CP) with or without obesity. METHODS: Twenty patients with obesity and 20 patients without obesity, all with CP, received SRP. Serum and GCF levels of resistin, adiponectin, leptin, tumour necrosis factor [TNF]-α and interleukin [IL]-6 were evaluated by enzyme-linked immunosorbent assay at baseline, 3, 6 and 12 months post-therapy. RESULTS: SRP reduced the amounts of TNF-α in deep sites and increased the concentration of adiponectin in shallow sites of non-obese patients (p < 0.05). SRP increased the concentrations of TNF-α and leptin in patients with obesity (p < 0.05). GCF levels of TNF-α were higher in patients with obesity than in patients without obesity at all time-points (p < 0.05). There were no changes in serum levels of any adipokines for any group after therapy (p > 0.05). Patients with obesity exhibited higher serum levels of leptin at all time-points and IL-6 at 3 months post-therapy (p < 0.05). CONCLUSIONS: Obesity may modulate systemic and periodontal levels of adipokines in favour of pro-inflammation, independently of periodontal therapy. SRP did not affect the circulating levels of adipokines in patients with or without obesity.

Lactoferrin levels in gingival crevicular fluid and saliva of HIV-infected patients with chronic periodontitis.

AIM: This study compared lactoferrin (LF) levels in the gingival crevicular fluid (GCF) and saliva between HIV-infected and noninfected patients with chronic periodontitis. METHODS: For each subject, LF levels were analyzed in one shallow site (SS; PD ≤3 mm), one deep site (DS; PD >5 mm) and in resting whole saliva. Two groups, 28 HIV-infected and 10 noninfected, were selected. RESULTS: Although the salivary LF levels were higher in HIV-infected than in noninfected individuals, especially in AIDS patients, this was not statistically significant (P > 0.05). Subgingival LF levels for SS and DS were lower among HIV-infected individuals, although AIDS patients showed the lowest levels. Age, smoking, gender, T CD4 lymphocytes levels and viral load did not influence subgingival LF levels, neither for SS nor for DP. Positive fungal culture was observed in 24 HIV-infected patients, but only observed in one in the control group. Overall, LF concentration was significantly higher in DS than SS, both in HIV-infected and noninfected individuals (P < 0.05) and salivary LF levels were always higher than GCF levels. CONCLUSION: The data indicate that LF levels in the GCF and saliva are not different between HIV-infected and noninfected patients with chronic periodontitis.

Assessment of oxygen saturation in dental pulp of permanent teeth with periodontal disease.

INTRODUCTION: In individuals with periodontal disease, dental pulp status should be determined before a treatment plan is made. Pulse oximeters are promising diagnostic tools to evaluate pulp vascularization. This study used pulse oximetry to determine the level of oxygen saturation in dental pulp of intact permanent teeth with periodontal attachment loss (PAL) and gingival recession (GR) and to evaluate the correlation between periodontal disease and level of oxygen saturation in the pulp. METHODS: This study included 67 anterior teeth of 35 patients; all teeth showed intact crowns, PAL, a periodontal pocket (PP), and GR. The teeth underwent periodontal examination, cold and electric pulp testing, and pulse oximetry measurements. The Pearson correlation coefficient and a linear regression coefficient were calculated to evaluate the degree of correlation between periodontal disease markers (PAL, PP, and GR) and the level of oxygen saturation in dental pulp. These tests also evaluated possible associations between oxygen saturation and cold and electric pulp testing. RESULTS: PAL, PP, and GR had negative correlations with oxygen saturation in dental pulp. Conversely, no statistically significant association was found between oxygen saturation in dental pulp and the response to electric sensibility testing. CONCLUSIONS: Oxygen saturation was lower in the pulp of permanent teeth with PAL, PP, and GR, indicating that periodontal disease correlates with the level of oxygen saturation in the pulp.

Expression of protease activated receptor-1 in chronic periodontitis.

BACKGROUND: Protease activated receptor-1 (PAR1) activation by thrombin may play a role in repair and homeostasis of periodontal tissues. The main objective of this study is to investigate PAR1 expression in patients with periodontitis, before and after non-surgical periodontal treatment, and to associate its expression with the presence of inflammatory biomarkers and PAR2 expression. METHODS: Gingival crevicular fluid (GCF) samples and clinical parameters, including probing depth, clinical attachment level, bleeding on probing, and gingival and plaque indices, were collected from periodontally healthy individuals and patients with moderate chronic periodontitis (CP) before and 6 weeks after periodontal non-surgical treatment. PAR1 and PAR2 messenger RNA (mRNA) at the GCF were evaluated by quantitative polymerase chain reaction (qPCR). Flow cytometry analysis identified the GCF PAR1-expressing cells. GCF inflammatory biomarkers were also determined. RESULTS: Clinical parameters were significantly improved after therapy (P <0.01). The qPCR analysis showed that, before therapy, PAR1 mRNA levels in CP were similar to controls. Periodontal treatment led to increased PAR1 expression in CP (P <0.05). PAR1 expression was inversely correlated to PAR2 expression and with interleukins 6 and 8, tumor necrosis factor-α, interferon-γ, and matrix metalloproteinase-2 levels. CONCLUSIONS: Periodontal treatment results in PAR1 overexpression in the GCF, and PAR1 expression is associated with decreased expression of inflammatory biomarkers and inversely correlated to PAR2 expression in the GCF. Therefore, the data suggest the importance of PAR1 mediating the known anabolic actions of thrombin in the periodontium.

Involvement of the Wnt-ß-catenin signalling antagonists, sclerostin and dickkopf-related protein 1, in chronic periodontitis.

AIM: The regulation of Wnt-ß-catenin signalling, which is crucial for osteoblast differentiation and for bone resorption, is driven by critical inhibitors such as sclerostin (SOST) and dickkopf-related protein 1 (DKK1). As such, the aim of this study was to evaluate the involvement of SOST and DKK1 in human chronic periodontitis. MATERIAL AND METHODS: Gingival biopsies and serum were sampled from systemically healthy non-periodontitis (n = 15) and chronic periodontitis subjects (n = 15). The mRNA and protein levels of SOST, DKK1 and TNF-α in periodontal tissues were measured by qPCR and by enzyme-linked immunosorbent assay (ELISA) respectively. Serum levels of SOST, DKK1 and TNF-α were assessed by ELISA. RESULTS: The mRNA and protein levels of SOST, DKK1 and TNF-α were significantly increased in the gingival tissues of the chronic periodontitis when compared to the non-periodontitis group (p < 0.05). In addition, circulating levels of SOST and TNF-α, but not DKK1, were higher in the periodontitis group than in the non-periodontitis group (p < 0.05). CONCLUSION: SOST and DKK1 were upregulated in the periodontal tissues of chronic periodontitis subjects, suggesting a possible role of these molecules on periodontal tissues.

Salivary IL-1ß and PGE2 as biomarkers of periodontal status, before and after periodontal treatment.

AIM: Interleukin-1ß (IL-1ß) and prostaglandin E2 (PGE2 ) are key inflammatory mediators involved in periodontitis. The purpose was to compare their salivary concentrations in relation to periodontal status and their changes after periodontal treatment, to determine their use as non-invasive diagnostic tools. MATERIALS AND METHODS: In this study, 74 subjects grouped in periodontally healthy, mild, moderate and severe periodontitis, according to clinical attachment level (CAL) and probing pocket depth (PPD) served as participants. IL-1ß and PGE2 were determined in unstimulated whole saliva by enzyme-linked-immunosorbent assay (ELISA). RESULTS: Interleukin -1ß increased with the severity of periodontitis with a large effect size in prediction of CAL (η(2)  = 0.35, p = 0.0001). PGE2 showed an increment in mild periodontitis and another in moderate. A significant effect size was also found between PGE2 and PPD (η(2)  = 0.12, p = 0.003). Both mediators decreased after periodontal treatment. With a selected threshold of 212 pg/ml, salivary IL1-ß predicted periodontitis with 78% sensitivity and 100% specificity. With a selected threshold of 121 pg/ml, salivary PGE2 predicted periodontitis with 78% sensitivity and 91% specificity. CONCLUSION: The high sensitivity and specificity of salivary IL-1ß and PGE2 in identifying periodontitis suggest a potential use as biomarkers for diagnosis of periodontitis presence and severity.

Determination of salivary levels of mucin and amylase in chronic periodontitis patients.

BACKGROUND AND OBJECTIVE: Patients with periodontal disease show differences in the profile of proteins in whole saliva. This profile reflects the nature and amplitude of the host response to a periodontal microbial challenge. Since periodontitis is a chronic inflammatory disease with different progression stages, the aim of the study was to evaluate the host response in these different clinical stages by assessing salivary flow rate, the concentrations of proteins and mucin and the amylase activity. MATERIAL AND METHODS: Sixty adult subjects were clinically examined and distributed into four groups (n = 15) according to the periodontal status, namely, healthy, mild, moderate and severe periodontitis. Whole saliva was collected for 5 min, followed by a second 5 min sampling period with stimulation by chewing a paraffin block, and flow rate was determined. Salivary proteins, amylase and mucin were determined by colorimetric methods. RESULTS: The concentrations of proteins, amylase and mucin increased in subjects with moderate and severe periodontal disease in unstimulated saliva, while flow rate decreased. A positive correlation was found between proteins and amylase or mucin concentrations among the different groups, indicating that the concentrations changed in the same way, being the response of salivary glands to the disease, possibly to enhance the protective potential of saliva. Mucin concentration was lower in the mild periodontitis group. Mechanical stimulation induced an increase in flow rate and output of proteins, amylase and mucin. CONCLUSION: Periodontitis induces an increase in the output of proteins, including mucin and amylase, thereby enhancing the protective potential of saliva, but this is accompanied by a decrease in flow rate.

Cytokine levels in sites of chronic periodontitis of poorly controlled and well-controlled type 2 diabetic subjects.

AIM: This study compared the levels of tumour necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-4, IL-17 and IL-23 in the gingival crevicular fluid (GCF) from well-controlled and poorly controlled type 2 diabetic subjects with chronic periodontitis, before and after periodontal therapy. MATERIAL AND METHODS: Eighteen well-controlled (glycated haemoglobin levels ≤8%) and 20 poorly controlled (glycated haemoglobin levels >8%) diabetic subjects were enrolled in this study. All subjects were submitted to non-surgical periodontal therapy. GCF sampling and clinical periodontal parameters were assessed before, 3 and 6 months post-therapy. Total amounts and concentrations of TNF-α, IFN-γ, IL-4, IL-17 and IL-23 in the GCF were analysed by enzyme-linked immunosorbent assay (ELISA). RESULTS: The levels of IL-17 were higher in poorly than in well-controlled subjects (p<0.05), whereas the levels of IFN-γ were increased in well- compared with poorly controlled subjects at all experimental groups (p<0.05). In addition, IL-4 levels were lower in well- than poorly controlled diabetic subjects at baseline (p<0.05). There were no differences between groups for TNF-α and IL-23 at any time points (p>0.05). CONCLUSION: These results indicate a predominance of pro-inflammatory T-helper type 1 (Th1)- or Th17-cytokines in sites of chronic periodontitis from type 2 diabetic subjects, according to their glycaemic control.

Polymorphism in the promoter region of the gene for 5-HTT in individuals with aggressive periodontitis.

Susceptibility to and development of periodontal disease have been associated with psychological conditions. Previous studies have associated the presence of polymorphism in the promoter region of the serotonin transporter with several behavioral traits and psychological conditions such as depression, anxiety, and stress. The short allele S has a reduced transcriptional efficiency and is associated with lowered serotonin expression and uptake. The purpose of the present study was to investigate the association between 5-HTTLPR polymorphism and aggressive periodontitis in a sample of Brazilian individuals. This study involved 61 individuals affected by aggressive periodontitis and 71 without periodontitis. Genomic DNA was obtained from oral swabs, amplified by polymerase chain reaction (PCR), and genotyped at 5-HTTLPR. The Chi-square test and multivariate logistic regression were used for statistical analysis. The aggressive periodontitis group displayed a significantly higher occurrence of genotype SS (P < 0.01) and of allele S (P < 0.01). After adjustment for gender and age, it was observed that genotype SS occurred 8 times more frequently in this group. Our findings suggest that 5-HTTLPR polymorphism might be associated with aggressive periodontitis in the Brazilian population.