Inclusion criteria for case  Age: 18-70 years. Both genders. Patient with histo-pathologically diagnosedoral squamous carcinoma Willing to participate in the study. Inclusion criteria for controls Healthy patients without any malignancy Patients relatively almost the same age group of cases  Exclusion criteria for cases  Patients with severe periodontitis and multiple carious teeth. Patients having other systemic diseases and cancer. Patients who cannot fulfill the inclusion criteria. Exclusion criteria for controls Having severe periodontal problemsor dental caries Suffering from any cancer