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    Malondialdehyde Levels in Dental Follicles of Asymptomatic Impacted Third Molars
    (W B Saunders Co-Elsevier Inc, 2011) Tekin, Umut; Kisa, Ucler; Guven, Orhan; Kurku, Huseyin
    Purpose: Increased levels of reactive oxygen species lead to oxidative stress and tissue damage. Malondialdehyde (MDA) is one of many low-molecular-weight endproducts of lipid peroxidation that increases with oxidative stress. The aim of this study was to determine oxidative stress in dental follicles (DFs) of radiologically asymptomatic impacted third molars (ITMs) using MDA. Materials and Methods: This study involved 40 DFs of 40 patients referred for clinically and radiographically asymptomatic ITMs. Forty healthy gingival tissues in the same patients were obtained during surgical removal of teeth as a control group. DF widths on periapical radiographs narrower than 2.5 mm were included in the study. All tissues samples were analyzed for MDA as an indicator of oxidative stress. Results: Levels of MDA were significantly higher in DFs from ITMs than those from healthy gingival tissues of the same patients (P < .01). Conclusion: The results suggest that significant oxidative stress may occur in DFs of asymptomatic ITMs. The findings suggest that increased MDA may play an important role in oxidative stress in DFs. In light of these preliminary findings of the present study, further investigations and comprehensive studies are required to determine the role of antioxidants that scavenge free radicals in DFs. (C) 2011 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 69:1291-1294, 2011
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    Relationship Between Activity of Gluthatione Peroxidase and Nitric Oxide in Synovial Fluid and the Progression of Temporomandibular Joint Internal Derangement
    (Lippincott Williams & Wilkins, 2015) Guven, Orhan; Tozoglu, Sinan; Tekin, Umut; Salmanoglu, Berrin; Gunes, Onur
    The purposes of this study were to measure the activity of glutathione peroxidase (GPX) and nitric oxide (NO) in the synovial fluid of patients with temporomandibular joint (TMJ) internal derangement (ID) and to indicate the relationship between the activity of GPX and NO and the progress of the ID. Twenty-six patients with TMJ ID were identified and classified according to Wilkes staging through clinical and radiologic examinations. Levels of GPX were determined indirectly by a coupled reaction with glutathione reductase. Levels of NO were measured colorimetrically. The activity of GPX and NO was observed to be progressively increasing as the stage of the TMJ ID progressed. There were significant correlations between the 2 substances and the Wilkes stages. Oxidative stress may have a role in the pathogenesis of TMJ ID. In synovial fluid, GPX and NO activities are increased as the stage of the disease increased. Increase in the activities of GPX might not be enough to prevent progression of the TMJ ID.
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    Tumor necrosis factor-alpha levels in the synovial fluid of patients with temporomandibular joint internal derangement
    (Churchill Livingstone, 2015) Guven, Orhan; Tekin, Umut; Salmanoglu, Berrin; Kaymak, Emre
    Purpose: The purpose of this study was to investigate the level of tumor necrosis factor-alpha (TNF-alpha) in the synovial fluid (SF) of patients with temporomandibular joint (TMJ) internal derangement and to show the relationship between the level of TNF-alpha and the severity of the disease. Materials and methods: Arthrocentesis was performed on 32 female and five male patients (aged between 17 and 45) referred to our clinic with the complaint of TMJ pain and discomfort. TNF-alpha levels were determined in the SF samples obtained during arthrocentesis. As a measure of pain, visual analog scale (VAS) scores were also evaluated. Results: There were statistically significant differences in VAS scores between the stages. VAS scores were found to be elevated as the stage of disease progressed. Increased levels of TNF-alpha were found in progressive stages of internal derangement. Conclusion: In our study, both SF TNF-alpha levels and pain levels (VAS scores) were found to be increased in patients with internal derangement as the stage of the disease progresses. TNF-alpha might contribute to the pathogenesis of synovitis and the degeneration of the TMJ cartilage and bone. (C) 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.