Resumen de Vitamin E Supplementation, Superoxide Dismutase Status, and Outcome of Scaling and Root Planing in Patients With Chronic Periodontitis: A Randomized Clinical Trial
Background: This study investigates the levels of superoxide dismutase (SOD) activity in serum and saliva of patients with chronic periodontitis (CP). In addition, the outcome of scaling and root planing (SRP) with and without vitamin E supplementation is evaluated in terms of changes in periodontal parameters and SOD activity in patients with CP.
Methods: Serum and salivary SOD activity in 38 patients with CP were compared with those of 22 systemically and periodontally healthy individuals (control group). At periodontal examination, serum and saliva samples were obtained. Patients with CP were randomly divided into treatment groups 1 (TG-1) and 2 (TG-2). SRP was performed for both groups, and TG-2 also received 200 mg (300 IU) vitamin E every other day. Periodontal parameters and SOD activity were evaluated after 3 months. SOD activity was determined using an SOD assay and enzyme-linked immunosorbent assay reader at 450 nm.
Results: SOD activity in both serum (P <0.05) and saliva (P <0.001) was lower in patients with CP compared with controls. After 3 months of follow-up, SOD activity improved in both treatment groups; however, the improvement in TG-2 was higher than in TG-1, along with more improvement in periodontal parameters. Serum SOD levels in TG-2 increased even above the level of the control group.
Conclusions: Systemic and local SOD levels are lowered in CP. Adjunctive vitamin E supplementation improves periodontal healing as well as antioxidant defense.
Periodontitis is an inflammatory disorder of the periodontium that affects the supporting tissues of teeth. The primary etiology of the disease is the interaction between the pathogenic microorganism and the host defensive mechanisms. One important mechanism of host defense is phagocytosis of invading microorganisms, which involves oxidative and non-oxidative killing of the ingested microorganism. Oxidative killing leads to the formation of toxic, highly reactive metabolites such as superoxide anion (O2-), collectively known as reactive oxygen species (ROS).1 The role of ROS in the tissue breakdown characteristic of periodontal disease has been widely discussed.2-6 Excessive ROS can initiate pathologic reactions in the tissues, including: 1) lysis of the cell membrane; 2) DNA fragmentation (mutagenic response); 3) inactivation of certain proteolytic enzyme inhibitors, e.g., tissue inhibitor of matrix metalloproteinase (TIMP) and a-1 antiproteinase; and 4) activation of proteolytic enzymes such as collagenase, gelatinase, and matrix metalloproteinase (MMP), resulting in collagenolysis and degradation of specific extracellular matrix components such as hyaluronic acid and proteoglycan.7 These events may be partially responsible for the periodontal breakdown in periodontitis.3,6 Antioxidants, which are present in all aerobic cells and extracellular fluids, provide protection against ROS.4,8 In the healthy state, homeostasis is maintained by the interaction of oxidants and antioxidants. Under pathologic conditions, the balance may be tilted toward the oxidative side, generating oxidative stress. Superoxide dismutase (SOD) is known to be one of the most prominent antioxidant enzymes in the body.8,9 SOD concentrations have been estimated in relation to periodontitis in various body fluids, with inconclusive results.9-11 Therefore, there is a need for careful assessment of SOD levels and their association with periodontitis.
Vitamin E is a group of �8 naturally occurring tocopherols. This vitamin is essential in humans for normal reproduction, development of muscles, resistance of red blood cells to hemolysis, and a number of other physiologic and biochemical functions. It is a potent antioxidant12-14 and has anti-inflammatory properties15-18 as well.
Vitamin E administration has been reported to significantly improve the levels of platelet antioxidant enzymes and retard lipid peroxidation.19-21 Furthermore, vitamin E�stimulated increase in the activities of antioxidant enzymes such as SOD has been demonstrated in patients with myocardial infarction as well as healthy controls.12 Perusal of the available English literature reveals no study concerning the influence of vitamin E administration during scaling and root planing (SRP) on periodontal healing. Taking this into consideration, the present study is designed to evaluate the effect of vitamin E administration as an adjunct to SRP on the outcome of periodontal therapy as well as on oral and systemic antioxidant status in terms of SOD activity. This study has two parts: 1) a cross-sectional study investigates the levels of salivary and serum SOD enzyme activity in patients with chronic periodontitis (CP) compared with healthy individuals; and 2) a prospective randomized parallel clinical trial explores the effect of periodontal treatment on local and systemic SOD activity levels of patients with CP. Additionally, an effort is made to explore the effect of adjunctive vitamin E supplementation on SOD levels and periodontal healing in terms of improvement in clinical parameters.
