Estimation of alpha-amylase in smokers with and without leukoplakia and oral cancer—A comparative study

Background: Cigarette smoke releases free radicles that have deleterious effects on the oral mucosa including potentially malignant disorders and oral cancer. In response to cigarette smoking, salivary flow rate increases as a defense activity along with a rise in alpha-amylase levels. Aim: To estimate salivary alpha-amylase levels in smokers with and without leukoplakia and oral cancer cases. Methods: This comparative study was carried out on 120 subjects; 30 subjects each in four groups which include non-smokers, smokers without oral lesions, smokers with leukoplakia, and smokers with oral squamous cell carcinoma (OSCC). Five microliters of unstimulated saliva were collected from the subjects by the spitting method. Alpha-amylase salivary levels were determined by spectrophotometric assay. Data collected were analyzed using a one-way ANOVA test. Results: No significant difference between alpha-amylase values was observed among smokers without oral lesions and smokers with leukoplakia groups when compared with non-smokers, but a significant difference was seen in the OSCC group in comparison with all three groups (smokers without oral lesions group vs OSCC group – P = 0.0045; leukoplakia group vs OSCC group P = 0.0326). Conclusion: Salivary alpha-amylase levels increased in smokers without any lesion and smokers with leukoplakia when compared with nonsmokers, although it was statistically not significant. Salivary alpha-amylase levels in oral cancer were significantly higher when compared with non-smokers, and smokers with and without leukoplakia. Smoking induced a change in salivary antioxidant levels. Changes in antioxidant levels can influence the deleterious effects of smoking on oral mucosa as well as systemic health.