Clinical and biochemical effects of erbium, chromium: yttrium, scandium, gallium, garnet laser treatment as a complement to periodontal treatment.

OBJECTIVE: The purpose of this study was to investigate the clinical effects of erbium, chromium: yttrium, scandium, gallium, garnet (Er, Cr: YSGG) laser treatment as a complementary to scaling and root planning (SRP) during the treatment of chronic periodontitis and gingival crevicular fluid (GCF) interleukin-1 beta (IL-1ß), interleukin-6 (IL-6), and interleukin-35 (IL-35) levels. MATERIALS AND METHODS: Forty patients with chronic periodontitis were divided into two equal groups at random to receive SRP alone and SRP followed by Er, Cr: YSGG laser treatment, which are control and test groups, respectively. Clinical attachment level (CAL), probing depth (PD), bleeding on probing (BOP), gingival index (GI), and plaque index (PI) were measured for all patients in both groups at baseline and again at the end of the 1st, 3rd, and 6th months following the treatment. Levels of GCF IL-1ß, IL-6, and IL-35 were analyzed by enzyme-linked immunosorbent assay. RESULTS: After periodontal treatment, CAL, PD, BOP, GI, and PI, which are clinical parameters analyzed, decreased significantly (P < 0.05) in both test and control groups. GCF volume, IL-1 ß, IL-6, and IL-35, levels in both groups proved statistically significant reductions compared to the baseline (P < 0.05), but no substantial variations were detected among both groups. CONCLUSION: According to these results, we can suggest that IL-35 may be related to the pathogenesis of periodontitis and that Er, Cr: YSGG laser can be used as an adjunct to SRP in periodontal treatment.

Relationship between alexithymia and chronic periodontitis.

OBJECTIVE: The aim of this study was to investigate the potential relationship between alexithymia and chronic periodontitis. MATERIALS AND METHODS: A case-control study of 222 male and female subjects aged 21-63 years was conducted. The participants were divided into a chronic periodontitis group (n = 114) and a control group (n = 108) with no history of periodontitis. The Toronto Alexithymia Scale (TAS-20) was used to evaluate alexithymia status of the subjects. Clinical data were collected on parameters such as the plaque index, bleeding on probing, probing depth, and the clinical attachment level (CAL). Socioeconomic data on the patients were also recorded. RESULTS: Chronic periodontitis group showed higher frequency in alexithymic patients as compared to control group. The proportion of high dental anxiety did not differ between the groups. The total TAS-20 score was statistically significantly higher in male subjects than in female subjects (P < 0.05). The bivariate analyses of the psychometric measures and the periodontal parameters revealed positive correlations with the severity of periodontal disease/CAL and the total TAS-20 score (P < 0.05). CONCLUSION: The results of the current study suggest that alexithymia is a possible risk factor for chronic periodontitis. Further research is needed to identify the underlying mechanism.

Large bandwidth mode order converter by differential waveguides.

In this article, we propose a large bandwidth mode-order converter design by dielectric waveguides with equal lengths but different cross-sectional areas. The efficient conversion between even and odd modes is verified by inducing required phase difference between the equal length waveguides of different widths. Y-junctions are composed of both tapered mode splitter and combiner to connect mono-mode waveguide to multi-mode waveguide. The converted mode profiles at the output port show that the device operates successfully at designed wavelengths with wide bandwidth. This study provides a novel technique to implement compact mode order converters and direction selective/sensitive photonic structures.

Radio-protective effects of Nigella sativa oil on oxidative stress in tongue tissue of rats.

OBJECTIVE: The aim of this study was to evaluate the effects of Nigella sativa (N.S.) oil against radiation-induced oxidative stress in the rat tongue. MATERIAL AND METHODS: Thirty-two Sprague-Dawley rats were randomly divided into four equal groups. Group 1 [control group(C)] did not receive N.S. oil or irradiation. Group 2 [sham control group(CN)] did not receive N.S. oil or irradiation but received 1-ml saline orally, plus sham irradiation. Group 3 [irradiation group(R)] received irradiation, plus 1-ml saline orally. Group 4 [irradiation plus N.S. oil group(RN)] received irradiation plus 1 g kg(-1) per day of N.S. oil orally for 10 days. The animals were euthanized on day 10, and tongue tissues were collected for evaluating biochemical oxidative parameters. RESULTS: The oxidative stress index, total oxidant status and lipid hydroperoxides levels in the R group were statistically higher than those in the C, CN and RN groups. The paraoxonase levels in the R group were statistically lower than those in the C, CN and RN groups. No statistically significant differences were detected between any of the groups, in terms of total antioxidant status and the arylesterase, ceruloplasmin and total sulfhydryl group levels. CONCLUSION: Nigella sativa (N.S.) oil may be a beneficial agent in protecting against ionizing radiation-related tissue injury.

Effects of periodontal therapy on disease activity and systemic inflammation in rheumatoid arthritis patients.

OBJECTIVE: This observational prospective cohort study aimed to evaluate the effects of non-surgical periodontal treatment on clinical periodontal measurements and systemic inflammatory mediator levels in low or moderate to highly active rheumatoid arthritis (RA) patients with chronic periodontitis. SUBJECTS AND METHODS: Rheumatoid arthritis activity was assessed with disease activity score test (DAS28). Thirty patients with RA with moderate to high disease activity (DAS28 ≥ 3.2) and chronic periodontitis (MHDA group) and thirty patients with RA with low disease activity (DAS28 < 3.2) and chronic periodontitis (LDA group) were enrolled in the study. The patients were monitored at the beginning and 3 months after undergoing periodontal therapy. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), tumour necrosis factor-alpha (TNF-α) levels in serum, DAS28 and periodontal parameters were evaluated. RESULTS: Erythrocyte sedimentation rate, CRP, TNF-α levels in serum, DAS28 and periodontal parameters exhibited similar and significant reduction 3 months after the non-surgical periodontal treatment. CONCLUSION: Non-surgical periodontal treatment may prove beneficial in reducing RA severity as measured by ESR, CRP, TNF-α levels in serum and DAS28 in low or moderate to highly active RA patients with chronic periodontitis.

Serum cytokine levels and periodontal parameters in ankylosing spondylitis.

BACKGROUND AND OBJECTIVE: Multiple studies support the role of periodontal disease in contributing to the chronic systemic inflammatory burden in a variety of diseases, including ankylosing spondylitis (AS), in the progression which the inflammatory process plays an important role. We assume that patients with AS are more likely to have periodontal disease than healthy individuals. The aim of this study was to determine the possible relationship between inflammatory periodontal diseases and AS by evaluating clinical periodontal parameters and serum cytokine levels. MATERIAL AND METHODS: Forty-eight adults with AS (35 women and 13 men; age range 18-56 years; mean age 34.27 years) and 48 age- and sex-matched systemically healthy control subjects participated in the study. The clinical periodontal parameters, venous blood and Bath Ankylosing Spondylitis Disease Activity Score were obtained, and serum C-reactive protein, tumour necrosis factor-α and interleukin-6 (IL-6) levels were evaluated. RESULTS: There was statistically no significant difference in the frequency of periodontitis between AS patients and the control group. Furthermore, there was no significant difference in probing depth, clinical attachment level and plaque index, and the only significant clinical difference between groups was in levels of bleeding on probing (p < 0.001). Serum concentrations of IL-6, tumour necrosis factor-α and C-reactive protein in the AS group were significantly higher than those in the control group (p < 0.001). In the AS group, there was a correlation between serum IL-6 levels and clinical attachment level (p < 0.001). CONCLUSION: The results of present study suggest that bleeding on probing was the only different periodontal parameter between the AS and the control group, and the periodontal status of patients with AS may be affected by IL-6 levels.

Study of different spectral regions and delay bandwidth relation in slow light photonic crystal waveguides.

We investigate slow light propagation in monomode photonic crystal waveguides with different spectral features such as constant group index, high bandwidth and low group velocity dispersion. The form of the waveguide mode alters dramatically and spans three different spectral intervals by tuning the size of the boundary holes. Namely, slope of the band gap guided mode changes sign from negative to positive toward the Brillouin zone edge. In between there is a transition region where modes have nearly zero slopes. Maximum group index occurs at these turning points at the expense of high dispersion and narrow bandwidth. The apparent trade-off relationship between group index and bandwidth is revealed systematically. We show that as the radius of the innermost hole is increased above a certain value, the former one decreases and the latter one increases both exponentially but with a different ratio. The product of average group index and bandwidth is defined as a figure of merit which reaches up to a value of approximately 0.30 after a detailed parametric search. The findings of the frequency domain analysis obtained by plane wave expansion method are confirmed via finite-difference time-domain study.