Intraoral Extranodal Natural Killer Cell/T-Cell Lymphoma of the Hard Palate.

Natural killer cell/T-cell lymphoma (NK/TL) is a rare subtype of non-Hodgkin's lymphoma (NHL) associated with the Epstein-Barr virus (EBV) and requires early detection, which can be very challenging. NK/TL often arises in the nasal cavity and can then spread to the oral cavity, but the case presented here is an unusual presentation of NK/TL in a 66-year-old edentulous male patient who initially presented an intraoral exophytic lesion in the palate that appeared within 3 months. We report the present case to highlight the challenges of reaching an accurate diagnosis given the diverse clinical manifestations of NK/TL.

Iranian Women and Health Care Providers' Perception of Oral Health in Pregnancy: A Qualitative Research.

Background: Periodontal diseases during pregnancy are associated with adverse outcomes. This study aimed to explain the perception of healthcare providers and pregnant women about oral health during pregnancy. Materials and Methods: This qualitative study was conducted with the approach of conventional content analysis in health centers of Hamadan, Iran, in 2020. To collect the data, semi-structured in-depth interviews with sixteen pregnant women and eight healthcare providers (gynecologist, midwife, and dentist) were used. Pregnant women with a singleton fetus, lack of chronic diseases and complications of pregnancy, willingness to participate in the study, and the ability to communicate properly were included in the study. Sampling was done purposefully with maximum variety. Data analysis accomplished according to the proposed steps by Graneheim and Lundman using MAXQDA 10 software. Results: "Belief in the importance of oral health in pregnancy," "Lack of a coherent structure for oral care," "Accepting the negative effect of pregnancy on oral health," and "The dilemma of treatment and non-treatment in pregnancy" were four categories extracted from the data. The theme of "Ignoring the mother for the fetus" was obtained as the main theme of the present study. Conclusions: The findings suggest that although mothers and healthcare providers have recognized the importance of oral health in pregnancy, underlying factors in society have led them to understand the mother's oral health should be neglected because of the fetus. This perception can have a negative impact on their behavior, performance, and the oral health of mothers.

Effectiveness of sodium bicarbonate and zinc chloride mouthwashes in the treatment of oral mucositis and quality of life in patients with cancer under chemotherapy.

AIM: The purpose of the study is to evaluate the effectiveness of sodium bicarbonate and zinc chloride mouthwashes on oral mucositis and quality of life in patients undergoing chemotherapy. DESIGN: The present study was a randomized controlled trial study. METHODS: One hundred forty-four patients with a cancer diagnosis were randomly assigned into three groups: sodium bicarbonate mouthwash (n = 48), zinc chloride mouthwash (n = 48) and placebo group (n = 48). The severity of mucositis and quality of life were examined blindly at the baseline and 3-week follow-up. RESULTS: The grade of oral mucositis decreased at the end of the third weeks in the sodium bicarbonate and zinc chloride groups rather than the placebo group (p < .001). The severity of oral mucositis in the sodium bicarbonate and zinc chloride groups decreased from end of the first week until third week (p < .001). In addition, there was significant difference in the severity of oral mucositis among the groups at the end of the second (p = .014) and the third weeks (p < .001). Also, there was a statistically significant difference in quality of life scores between the sodium bicarbonate and zinc chloride mouthwash with the placebo group (p < .001). CONCLUSION: Zinc chloride and sodium bicarbonate mouthwashes were effective in treating and reducing the severity of oral mucositis, and subsequently improving quality of life in patients with cancer under chemotherapy. Therefore, we can recommend zinc chloride and sodium bicarbonate at the beginning of chemotherapy to improve oral health and promoting quality of life in these patients.

Potential biomarkers and signaling pathways associated with the pathogenesis of primary salivary gland carcinoma: a bioinformatics study.

Salivary gland carcinoma (SGC) is rare cancer, constituting 6% of neoplasms in the head and neck area. The most responsible genes and pathways involved in the pathology of this disorder have not been fully understood. We aimed to identify differentially expressed genes (DEGs), the most critical hub genes, transcription factors, signaling pathways, and biological processes (BPs) associated with the pathogenesis of primary SGC. The mRNA dataset GSE153283 in the Gene Expression Omnibus database was re-analyzed for determining DEGs in cancer tissue of patients with primary SGC compared to the adjacent normal tissue (adjusted p-value < 0.001; |Log2 fold change| > 1). A protein interaction map (PIM) was built, and the main modules within the network were identified and focused on the different pathways and BP analyses. The hub genes of PIM were discovered, and their associated gene regulatory network was built to determine the master regulators involved in the pathogenesis of primary SGC. A total of 137 genes were found to be differentially expressed in primary SGC. The most significant pathways and BPs that were deregulated in the primary disease condition were associated with the cell cycle and fibroblast proliferation procedures. TP53, EGF, FN1, NOTCH1, EZH2, COL1A1, SPP1, CDKN2A, WNT5A, PDGFRB, CCNB1, and H2AFX were demonstrated to be the most critical genes linked with the primary SGC. SPIB, FOXM1, and POLR2A significantly regulate all the hub genes. This study illustrated several hub genes and their master regulators that might be appropriate targets for the therapeutic aims of primary SGC.

Comparison of Salivary Antioxidants and Oxidative Stress Status in Gestational Diabetes Mellitus and Healthy Pregnant Women.

BACKGROUND: One of the most common complications of pregnant women is gestational diabetes mellitus (GDM). Oxidative stress can play an important role in GDM. OBJECTIVE: The aim of this study was to evaluate salivary antioxidants and oxidative stress markers in GDM. METHODS: Twenty pregnant women with GDM and 20 healthy pregnant women with normal blood glucose test participated in this study. Five mL of unstimulated saliva samples were collected. Spectrophotometric assay was carried out for sialo-chemical analysis. Stata software was used for data analysis. RESULTS: The GDM group exhibited no significant difference in salivary total antioxidant capacity and malondialdehyde compared to the healthy control group. All antioxidants markers, the uric acid, total antioxidant, peroxidase and catalase, decreased in GDM group that the difference of peroxidase and catalase was statistically significant. All of oxidative stress markers, the salivary malondialdehyde, total oxidative stress and total thiol, increased in GDM group. GDM group exhibited significantly higher salivary total oxidative stress levels. CONCLUSION: Catalase level was significantly lower and total oxidative stress was significantly higher. These two markers might have significant importance and might exhibit early changes compared to other factors in GDM. Some salivary antioxidants might have diagnostic, prognostic or therapeutic implications in GDM. Other studies with large sample size on salivary and blood samples need to be done to confirm these properties and salivary samples using instead of blood samples in GDM biomarkers changes.

Evaluation of Salivary Helicobacter pylori, Calcium, Urea, pH and Flow Rate in Hemodialysis Patients.

BACKGROUND: Helicobacter pylori infection is identified as a major cause of stomach ulcers, chronic inflammation and gastric cancer in hemodialysis patients. Dialysis also leads to changes in the composition and flow of saliva. OBJECTIVE: The aim of this study was to investigate the salivary Helicobacter pylori infection, Calcium, Urea, pH and flow rate in hemodialysis patients in comparison to the healthy control group. METHODS: In this study 48 hemodialysis patients and 48 healthy subjects were compared. The prevalence of Helicobacter pylori infection was determined by PCR method. Calcium, Urea, pH, salivary flow and gastrointestinal complications in both groups were measured and compared. RESULTS: Prevalence of Helicobacter pylori was 12.48 (25.0%) in the study group and 2.48 (4.2%) in the controls (P=0.000). Urea, calcium and pH were significantly higher in the patient group. The mean salivary flow rate decreased significantly in the patient group. 58.3% of patients group had gastrointestinal complications. CONCLUSION: Oral cavity as an important external source of Helicobacter pylori may play an important role in gastrointestinal problems of hemodialysis patients. Helicobacter pylori, Urea, calcium and pH were significantly higher in the patient group. Chronic renal failure can increase pH, urea and calcium in saliva and decrease salivary flow rate.

Evaluation of the Status of Salivary Antioxidants in Dental Caries.

BACKGROUND AND AIM: Dental caries is a communicable and the most prevalent infectious disease worldwide. Salivary oxidative stress and antioxidants may play a pivotal role in caries prevention, progression and pathogenesis. In this study, salivary superoxide dismutase, peroxidase, glutathione peroxidase, catalase and uric acid levels were evaluated in dental caries. MATERIALS AND METHODS: One hundred male and female students in two groups (n=50) were subdivided into caries-active and caries-free (25) groups. Whole saliva samples were collected in the morning, and the salivary antioxidant levels were measured by a spectrophotometric assay. The data were analyzed using SPSS. RESULTS: The caries-active group had higher peroxidase, uric acid, catalase and glutathione peroxidase levels, and lower superoxide dismutase level as compared to the caries-free group. The comparison between males and females showed lower peroxidase, catalase and uric acid levels and higher glutathione peroxidase levels in the female group. CONCLUSION: The caries-active group had altered salivary antioxidant levels. Therefore, it was concluded that salivary antioxidants have significant effects on oral and dental health.

Evaluation of Salivary Lipid Peroxidation End Product Level in Dental Caries.

BACKGROUND: Tissue destruction can be measured by the level of lipid peroxidation (LP) end products. Since free radicals are very reactive with low survival time, the level of free radicals and oxidative stress activity are measured indirectly by tissue damage end product assessment, i.e. Malondialdehyde (MDA) that is a final end product of LP. OBJECTIVE: The aim of this study was to evaluate salivary MDA level as an indicator of oxidative stress; in caries-active and caries-free students. METHODS: A total of 100 male and female students, 15-17 years of age, participated in this casecontrol study. Five mL of whole saliva was obtained. Salivary MDA level was measured spectrophotometrically. Statistical comparisons were performed with Student's t-test, using SPSS 13. RESULTS: Salivary MDA level was significantly higher in the caries-active group compared to the control caries-free group. MDA was also slightly lower in males. CONCLUSION: Higher MDA level might indicate caries-induced oxidative stress. In this study there was a relationship between salivary MDA level and dental caries. Therefore oxidative stress suppression might prevent caries initiation and progression.

Evaluation of Salivary Antioxidants and Oxidative Stress Markers in Type 2 Diabetes Mellitus: A Retrospective Cohort Study.

BACKGROUND: Diabetes Mellitus (DM) is a progressive metabolic disorder. OBJECTIVE: The aim of this study was to investigate the relationship between antioxidant and oxidative stress markers in the saliva of patients with type 2 DM and a healthy control group. METHODS: In this study, 20 patients with diabetes and 20 healthy individuals were evaluated. Salivary antioxidants markers consisted of total antioxidant capacity (TAC), uric acid (UA), peroxidase and catalase. Oxidative stress markers included total oxidant status (TOS), malondealdehyde (MDA) and total thiol (SH). Sialochemical analysis was performed with spectrophotometric assay. All the statistical analyses were conducted using STATA software. RESULTS: TAC decreased significantly in patients with diabetes. Although salivary UA and peroxidase were lower in patients with diabetes compared to the control group, the difference was not significant. Salivary catalase in patients with diabetes was significantly lower than that in the control group. MDA and TOS exhibited significantly higher levels in type 2 DM. SH levels were slightly higher in DM. CONCLUSION: According to the results of the present study, there were some changes in the salivary levels of some antioxidants and oxidative stress markers in patients with type 2 DM and could be measured as an indicator of serum changes.

Evaluation of Salivary Antioxidants and Oxidative Stress Markers in Male Smokers.

BACKGROUND: Cigarette smoke free radicals can cause cellular damage and different diseases. All the body fluids have antioxidants which protect against free radicals. OBJECTIVE: The aim of this study was to evaluate salivary total antioxidant capacity and peroxidase, uric acid and malondialdehyde levels in smokers and a nonsmoking control group. METHODS: Unstimulated saliva was collected from 510 males. A total of 259 subjects were current smokers and 251 were non-smokers. The levels of salivary total antioxidant capacity, uric acid, peroxidase and malondialdehyde were measured using standard procedures. Data were analyzed with t test and ANOVA. RESULTS: The smokers were younger and dental hygiene index was higher than healthy nonsmoking controls. The mean total antioxidant capacity in smokers and nonsmokers was 0.13±0.07 and 0.21±011, respectively (P=0.001). Smokers had significantly lower peroxidase and uric acid levels than healthy controls. In addition, the mean malondialdehyde levels in the smokers and nonsmokers were 4.55 ±2.61 and 2.79 ±2.21, respectively (P=0.001). CONCLUSION: Cigarette smoke produces free radical and oxidative stress, causing many side effects. Salivary antioxidant levels decreased and malondialdehyde levels increased in smokers, indicating the high oxidative stress among smokers compared to nonsmokers. Cigarette smoke had deleterious effects on main salivary antioxidants levels.

Salivary Antioxidant and Oxidative Stress Marker Levels in HIV-Positive Individuals.

BACKGROUND: HIV infections are a worldwide health problem. HIV infection reduces CD4+ cell counts. Oxidative stress might play an important role in the stimulation of virus replication and immunodeficiency. Saliva might be the first line of defense against oxidative stress. OBJECTIVE: The aim of this study was to evaluate the oxidative stress marker and antioxidant levels of saliva in HIV-infected patients by measuring total antioxidant capacity and malondialdehyde level. METHODS: A total of 49 HIV-positive patients and 49 healthy HIV-negative individuals were randomly selected. All the patients were clinically examined. Five mL of unstimulated whole saliva was collected and evaluated by spectrophotometric assay. Data were analyzed with STATA 11. RESULTS: Mean ages of the case and control groups were 28 and 33 years, respectively. Salivary malondialdehyde levels were significantly higher in the HIV-positive group (3.68±2.26) compared to the healthy control group (2.79±1.91). Levels of salivary total antioxidant capacity were significantly lower in the HIV-positive group (0.20± 0.09) compared to the control group (0.27±0.10). CONCLUSION: The antioxidant defense system in HIV-positive individuals was low and oxidative stress was high in this population. Saliva might be used as a diagnostic tool for antioxidant changes in HIV-positive patients in the future. There were changes in salivary antioxidant defense system and oxidative stress in HIV-positive individuals. Antioxidant supplements might help local salivary and general health statuses.

Evaluation of Salivary Alkaline Phosphatase and Albumin in HIV Infected Patients: A Historical Cohort Study.

BACKGROUND: Saliva is a very important complex biological oral fluid .Antioxidants are present in all body fluids. Uric acid, albumin and vitamins are some of the non- enzymatic molecular antioxidants. Alkaline phosphatase is related to cell injury and death. OBJECTIVES: The aim of this study was the evaluation of salivary alkaline phosphatase and albumin level in HIV positive patients in comparison to healthy control group. METHODS: Case groups were 49 HIV positive subjects, compared with 49 healthy control group. Oral clinical examination was carried out. Five ml unstimulated whole saliva was collected during 5 min with the Navazesh method. Alkaline phosphatase was determined by spectrophotometric assay. Albumin was assessed by the nephelometric method. RESULTS: The results of this study showed significantly lower salivary albumin in the case group in comparison to healthy control group (p= 0.001). HIV positive group had greater alkaline phosphatase than the healthy control group. However, this difference was not statistically significant (p=0.458). CONCLUSION: Salivary albumin level was significantly decreased and salivary alkaline phosphatase level slightly increased in HIV positive patients in comparison to healthy control group. All of the HIV infected patients were in early phase of HIV infection with normal immune status. More research is needed to estimate these enzymes changes in late phase of HIV infection and AIDS step.

Evaluation of salivary acetylcholinesterase and pseudocholinesterase in patients with Alzheimer's disease: A case-control study.

AIM: The aim of this study was to evaluate acetylcholinesterase (AChE) and pseudocholinesterase (PChE) in whole saliva in patients with Alzheimer's disease (AD) and in healthy subjects. Saliva has a high potential for keeping track of general health and diseases. AD is a type of dementia with reduction in brain cholinergic markers that causes memory, thinking, and behavior problems. Up to 90% decrease in AChE activity has been observed in AD. METHODS AND RESULTS: Thirty healthy subjects and 30 patients with AD participated in this study. Saliva samples were collected from 8 to 10 am. AChE and PChE of saliva were assessed by the Ellman method. Statistical comparison was performed using SPSS 16 for t-test. The activity of AChE and PChE significantly increased in the group with AD compared to the healthy subjects. Sex had no effect on the activities of these enzymes. No correlation existed between the duration of illness and enzymatic activity. The enzyme levels reduced with age. CONCLUSION: AChE and PChE levels were increased in saliva samples of patients with AD. Therefore, saliva has the potential for being used for the purpose of biomarker evaluation to replace cerebrospinal fluid in patients with AD.

Salivary and Serum Antioxidant and Oxidative Stress Markers in Dental Caries.

Dental caries is the most common, chronic, noncommunicable, preventable oral disease worldwide. Oxidation may play an important role in dental caries initiation and progression. Antioxidants in body fluids protect cells. The aim of this study was to evaluate salivary and serum total antioxidant capacity (TAC) and malondialdehyde (MDA) levels in dental caries. A total of 118 healthy caries-free and caries-active male and female students participated. Caries was detected clinically. Unstimulated whole-saliva samples and blood samples were obtained. Sialochemical analysis was carried out by spectrophotometric assay. Data were analyzed with the Student t test using STATA 11. Salivary and serum TAC levels in the case and control groups did not show any significant differences. Mean salivary MDA levels in the case and control groups were 0.71 ± 0.1 and 0.35 ± 0.06 nmol/mL, respectively. The results showed significantly higher levels of salivary and serum MDA in the case group compared to the healthy control group. The oxidative stress marker was significantly higher in the caries group compared to the healthy control group. Antioxidants were not significantly different between the two groups. MDA can be produced by dental caries, resulting in a decrease in antioxidant levels, causing disease progression. Further studies are necessary to determine whether MDA is the cause or effect of the disease.

Evaluation of Salivary Uric Acid and pH in Human Immunodeficiency Virus Infected Patients: A Historical Cohort Study.

OBJECTIVE: Antioxidants protect the body against cellular damage. Saliva has immunological, enzymatic and antioxidant defense systems. Uric acid is the main and predominant salivary antioxidant. The aim of this study was to evaluate salivary uric acid levels and pH in HIV-infected patients in the west of Iran. METHODS: HIV-infected patients were selected from behavioral advisory centers of Hamadan and Kermanshah Provinces, west of Iran. Saliva was collected between 8 and10 in the morning. Five mL of whole unstimulated saliva was collected in 5 minutes by spitting into sterilized Falcon tubes based on Navazesh method; pH was measured with a pH meter and uric acid was assessed with spectrophotometric method. Data were analyzed with STATA 12. RESULTS: Salivary pH in the HIV-positive group was lower (6.99±0.46) than the healthy controls (7.14±1.03) but the difference was not statistically significant (P=380). Uric acid concentrations in HIV-infected patients (2.94±2.14) were significantly lower in comparison to the healthy controls (5.21±2.30). The results showed a statistically significant decrease in the case group (P=0.001). Mean age and DMFT index of the case group were higher than the control group. CONCLUSION: Uric acid, the main antioxidant of saliva, was significantly lower in HIVinfected individuals; pH also was lower in these patients. HIV can alter salivary antioxidant status, which can influence patients' oral health status. Diet with antioxidant properties might be helpful in these patients. More research is necessary to discover true antioxidant and salivary changes and their relation with HIV consequences in future.

Evaluation of the miRNA-146a and miRNA-155 Expression Levels in Patients with Oral Lichen Planus.

BACKGROUND: Oral Lichen Planus (OLP) is a chronic autoimmune disease that could be considered as a potential premalignant status. OBJECTIVE: To evaluate the miRNA-146a and miRNA-155 expression levels in patients with oral Lichen planus lesions compared to healthy subjects with normal oral mucosa. METHODS: Forty patients with oral lichen planus and 18 healthy age and gender-matched controls were recruited in this case-control study. Oral lichen planus was diagnosed clinically and pathologically. The expression levels of two miRNAs in peripheral blood samples were determined using commercial TaqMan MicroRNA Assays. Relative quantification of gene expression was calculated by the 2-ΔΔct method. RESULTS: The expression levels of miRNA-146a and miRNA-155 in patients with oral Lichen planus were significantly higher than those of healthy controls. Also, a direct but insignificant correlation was found between miRNA-155 and miRNA-146a expression levels among the patient group. CONCLUSION: Our findings indicate that miRNA-146a and miRNA-155 could be potential biomarkers for the immunopathogenesis of oral lichen planus.

Evaluation of Salivary Melatonin Levels in HIV-positive Patients: A Historical Cohort Study.

BACKGROUND: Human immunodeficiency virus (HIV) affects lymphocytes, resulting in acquired immunodeficiency syndrome. Oxidative stress may play an important role in HIV pathogenesis. Melatonin has antioxidant, antiinflammatory and immunomodulatory effects. OBJECTIVE: The aim of this study was to evaluate salivary melatonin levels in HIV-positive patients and a healthy control group. METHODS: Forty-nine HIV-positive and 49 healthy subjects were included in this study. Patients' drug consumption and clinical examination results were registered in questionnaires. Unstimulated whole saliva was collected in the morning. The melatonin levels were measured by melatonin ELISA kits. Statistical analyses were performed with STATA 12, using t-test and chi-squared test. RESULTS: Salivary melatonin levels were significantly lower in the case group in comparison with the healthy control group (P=0.001). Age was significantly higher in the case group. Chi-squared test showed no statistically significant difference between the case and control groups in smoking (P=0.591) and addiction (P=0.204) but gender differences were observed (P=0.001). CONCLUSION: Salivary melatonin level as an antioxidant was lower in HIV-positive patients. Further studies are necessary to understand the exact role of melatonin in HIV-positive patients and its therapeutic effects.

Evaluation of Salivary and Serum Antioxidant and Oxidative Stress Statuses in Patients with Chronic Periodontitis: A Case-Control Study.

Aim: Local bacteria stimulate polymorphonuclear neutrophils to release reactive oxygen species in periodontitis. Increased levels of oxidative stress play a significant role in the pathogenesis of periodontitis. Therefore, this study aimed to evaluate total salivary and serum antioxidant capacity and malondialdehyde in patients with chronic periodontitis. Materials and methods: Fifty-five healthy subjects and 55 patients with chronic periodontitis, with an age range of 30-50 years, were evaluated. After clinical examination and case selection, unstimulated whole saliva was collected in the morning. Blood samples were taken from the antecubital vein. Total antioxidant capacity and malondialdehyde levels were evaluated by spectrophotometric assay. Data were analyzed with t-test, using Stata.11 software program. Results: The periodontitis group exhibited lower salivary (0.16) and serum (0.36) total antioxidant capacity (P = 0.11) compared to the control group. Mean salivary malondialdehyde levels in the case and control groups were 0.80 ± 0.09 and 0.42 ± 0.08, respectively. The results showed significantly higher levels of salivary and serum malondialdehyde in the periodontitis group. Gender did not have any effect on antioxidant and oxidative stress levels. Conclusion: This study indicated increased levels of salivary and serum oxidative stresses in patients with chronic periodontitis. Total antioxidant capacity was mildly lower in the saliva and serum of these patients. Higher malondialdehyde levels with no changes in antioxidant status can result in systemic and local complications in these patients.

Evaluation of Salivary Vitamin C and Catalase in HIV Positive and Healthy HIV Negative Control Group.

BACKGROUND: Saliva is a complex oral biologic fluid secreted by major and minor salivary glands. Saliva has immunological, enzymatic and antioxidant defense mechanisms. Infection with human immunodeficiency virus (HIV) is a life-threatening disease. OBJECTIVE: The aim of this study was to evaluate salivary vitamin C and catalase levels in HIV-positive patients in comparison to a healthy control group. METHOD: Forty-nine HIV-infected individuals and 49 healthy subjects were selected. Five mL of unstimulated saliva was collected in 5 minutes using a sterilized Falcon tube with Navazesh method. Catalase and vitamin C levels were assessed by spectrophotometric assay. Data were analyzed with STATA 12. RESULTS: Salivary catalase levels were 7.99±2.40 and 8.37±1.81 in the case and control groups, respectively. Catalase level was lower in the case group but the difference was not statistically significant (P=0.380). Salivary vitamin C levels in the case and control groups were 3.76±1.92 and 4.87±2.20, respectively (P=0.009). CONCLUSION: HIV can alter salivary antioxidant capacity as well as vitamin C and catalase levels. Saliva may reflect serum antioxidative changes in these patients. Therefore, further research is necessary on salivary and serum oxidants and the antioxidant changes.

Evaluation of salivary catalase, vitamin C, and alpha-amylase in smokers and non-smokers: a retrospective cohort study.

BACKGROUND: Saliva and its defence systems such as antioxidants and minerals are very important in the pathogenesis of different diseases. Cigarette smoking has many destructive effects. Oxidative stresses play an important role in the side effects of smoking. This study assessed the effect of cigarette smoking on salivary levels of catalase, vitamin C, and α-amylase. METHODS: This retrospective cohort study was carried out in Hamadan, Iran, on 510 subjects; 259 subjects were smokers (the exposed group) and 251 were non-smokers (the unexposed group). Five microliters of unstimulated saliva was collected by spitting method. Catalase, vitamin C, and α-amylase salivary levels were determined by spectrophotometric assay. Data were analyzed with t-test using STATA 12. RESULTS: Vitamin C level in smokers was significantly lower than that in non-smokers. The salivary catalase levels were lower and α-amylase levels were higher in smokers, but the differences were not statistically significant (P = 0.416 and P = 0.265, respectively). Smokers were younger than non-smokers. CONCLUSION: Smoking resulted in a change in salivary antioxidant levels. Changes in antioxidant levels can influence the deleterious effects of smoking on oral mucosa; it might also indicate systemic changes and changes in the serum levels of oxidative agents. Further studies are necessary to understand the mechanisms and real effects of smoking, to determine the benefits of supplementary antioxidants for treatment and to reduce the dangerous side effects of smoking.