***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objective : Chronic periodontitis ( CP ) is associated with increased levels of blood reactive oxygen species ( ROS ) . So , treatment of CP may lead to decrease in blood ROS . However , not much literature is available comparing the effect of surgical and non-surgical periodontal treatment on blood ROS levels . Reactive oxygen metabolites ( ROMs ) are a useful measure of blood ROS . The aim of this study was to investigate the effect of periodontal treatment on plasma ROM levels in CP patients . Material s and Methods : Thirty CP patients and 15 controls were monitored . Plasma sample s were collected at baseline and the clinical parameters were recorded . The CP patients were r and omly divided into two groups : Scaling and root planing ( Group II ) and periodontal flap surgery ( Group III ) . Both groups were re-evaluated 1 and 2 months after therapy . Clinical parameters were review ed , plasma sample s collected , and ROM levels were determined using a spectrophotometric technique . Results : At baseline , the ROM levels for Group II and Group III were 519.8 ± 62.4 and 513.4 ± 74.7 CARR U , respectively , which were higher than Group I value ( 282.9 ± 23.9 , P < 0.001 ) . Periodontal treatment in CP patients result ed in improvement of clinical parameters and a highly significant reduction in plasma ROM level ( P < 0.001 ) after 2 months . Also , there was a more significant reduction in plasma ROM levels in Group III as compared to Group II ( P < 0.05 ) . Conclusions : In CP patients , surgical periodontal treatment was more effective in lowering the plasma ROM levels than when non-surgical periodontal treatment was performed alone and , therefore , may be more beneficial in reducing systemic oxidative stress Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more Background : Plasma glutathione peroxidase ( eGPx ) is an important selenium containing antioxidant in human defense against oxidative stress . While crevicular fluid ( GCF ) eGPx levels and its association with periodontal disease is well documented , there is no data on correlation of GCF and serum eGPx levels in chronic periodontitis . Hence this study was undertaken to further probe into the role of oxidative stress in periodontal diseases and effect of nonsurgical periodontal therapy ( NSPT ) by correlating GCF and serum levels of eGPx . Material s and methods : Thirty subjects ( 16-Males and 14-Females ; age : 30–38 years ) participated in the study . The subjects were divided , based on gingival index , probing pocket depth and clinical attachment level into : Healthy ( group-1 , n=10 ) , Gingivitis ( group-2 , n=10 ) and Periodontitis ( group-3 , n=10 ) . Chronic periodontitis patients after  NSPT constituted group 4 . GCF and serum sample s collected from each subject were quantified for eGPx levels using Enzyme linked Immunosorbent Assay . Results : The mean eGPx concentrations increased from health ( 14.01 ng/μl and 78.26 ng/ml ) to gingivitis ( 22.86 ng/μl and 90.44 ng/ml ) and then to periodontitis ( 29.89 ng/μl and 103.43 ng/ml ) , in GCF and serum respectively . After NSPT , there was statistically significant reduction in eGPx concentration in GCF and serum ( 19.41 ng/μl and 85.21 ng/ml ) . Further , all the GCF eGPx values showed a positive correlation to that of serum eGPx level . Conclusion : Thus , increased eGPx concentration in GCF can be considered as an indicator of local increase in oxidative stress . While , increase in serum eGPx levels indicates that periodontal disease can also lead to increased oxidative stress at the systemic level Aim The purpose of this study was to investigate the effects of non-surgical periodontal treatment on hemoglobinA1c ( HbA1c ) levels , oxidative stress balance and quality of life ( QOL ) in patients with type 2 diabetes mellitus ( T2DM ) compared to no periodontal treatment ( simple oral hygiene instructions only ) . Methods The design was a 6-month , single-masked , single center , r and omized clinical trial . Patients had both T2DM and chronic periodontitis . Forty participants were enrolled between April 2014 and March 2016 at the Nephrology , Diabetology and Endocrinology Department of Okayama University Hospital . The periodontal treatment group ( n = 20 ) received non-surgical periodontal therapy , including scaling and root planing plus oral hygiene instructions , and consecutive supportive periodontal therapy at 3 and 6 months . The control group ( n = 17 ) received only oral hygiene instructions without treatment during the experimental period . The primary study outcome was the change in HbA1c levels from baseline to 3 months . Secondary outcomes included changes in oxidative stress balance ( Oxidative-INDEX ) , the Diabetes Therapy-Related QOL and clinical periodontal parameters from baseline to 3 months and baseline to 6 months . Results Changes in HbA1c in the periodontal treatment group were not significantly different with those in the control group at 3 and 6 months . Systemic oxidative stress balance and QOL significantly improved in the periodontal treatment group compared to the control group at 3 months . In the subgroup analysis ( moderately poor control of diabetes ) , the decrease in HbA1c levels in the periodontal treatment group was greater than that in the control group at 3 months but not significant . Conclusions In T2DM patients , non-surgical periodontal treatment improved systemic oxidative stress balance and QOL , but did not decrease HbA1c levels at 3 months follow-up . Trial registration Current Controlled Trials UMIN-ICDR UMIN 000013278 ( Registered April 1 , 2014 ) 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 sample s were obtained . Patients with CP were r and omly 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 
    Output:
    
The most common OxS biomarkers used were 8-hydroxydeoxiguanosine ( 8-OHdG ) , total oxidant status ( TOS ) , and total antioxidant status ( TAS ) .
After treatment , most of the studies reported a decrease in 8-OHdG concentration in the gingival crevicular fluid ( GCF ) and saliva .
In addition , the salivary concentration of this biomarker was similar to periodontally healthy patients .
Periodontal therapy was effective in reducing TOS in GCF , saliva , and serum in most studies .
TAS , however , responded inconsistently to the periodontal intervention .
Periodontal therapy reduces the levels of OxS biomarkers , even to values similar to those found in periodontally healthy individuals .