## 3 Results  
The patients' preview and characteristics are presented in Table 1. The most frequent affected site by OSCC was the tongue (C02.3) in 84 patients (35.1%). The second most frequent site was the inferior alveolar ridge mucosa (C03.1) in 43 patients (18%). The least frequent site was the oral vestibule (C06.1) in 1 patient (0.4%) (Figure 1). \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Characteristics** & **Test Group** & **Control Group** & **Total** \\ \hline
**Average Age** & 65.56 & 65.75 & 65.66 \\
**Age** & n (\%) & n (\%) & n (\%) \\ \(<\)50 & 41 (17.2) & 19 (7.9) & 60 (12.6) \\
50–65 & 69 (28.9) & 96 (40.2) & 165 (34.5) \\
65–80 & 90 (37.6) & 96 (40.2) & 186 (38.9) \\ \(>\)80 & 39 (16.3) & 28 (11.7) & 67 (14) \\
**Gender** & & & \\ Male & 114 (48) & 116 (49) & 230 (48) \\ Female & 125 (52) & 123 (51) & 248 (52) \\
**Tobacco Status** & & & \\ Non-smokers & 103 (43.1) & 118 (49.4) & 221 (46.2) \\ Smokers & 136 (56.9) & 121 (50.6) & 257 (53.8) \\
**Tobacco consumption amount (pack years)** & & & \\ \(\leq\)20 & 52 (21.8) & 47 (19.7) & 99 (20.7) \\
21–40 & 46 (19.2) & 40 (16.7) & 86 (18) \\ \(>\)40 & 38 (15.9) & 34 (14.2) & 72 (15.1) \\
**Alcohol Status** & & & \\ Non-drinkers & 125 (52.3) & 144 (60.3) & 269 (56.3) \\ Drinkers & 114 (47.7) & 95 (39.7) & 209 (43.7) \\
**Alcohol consumption amount (drinks/week)** & & & \\ \(<\)7 & 21 (8.8) & 31 (13) & 52 (10.9) \\
7–10 & 35 (14.6) & 29 (12.1) & 64 (13.4) \\ \(>\)10 & 58 (24.3) & 35 (14.6) & 93 (19.4) \\
**Alcohol abuse** & 12 (5) & 0 (0) & 12 (2.5) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Patients’ preview and characteristics. Figure 1: Distribution of cases according to the sites of Oral Squamous Cell Carcinoma (OSCC) defined by the 10 th edition of the International Classification of Diseases (ICD-10) version 2010 in the Test Group (TG). Approximately 46.2% of the study participants were non-smokers. In the TG, the number of smokers (n = 136) was slightly higher than that of CG (n = 121). No statistical significance was observed in regard to the smoking status with OR of 1.004 (95% CI 0.996-1.012) and \(p\) = 0.294. Among the smokers, the average of tobacco consumption in TG was 20.6 pack years and in CG it was 15.1 pack years (Table 2). The high rate of tobacco consumption (\(>\)40 pack years) showed an associated risk with OR of 1.035 (95% CI 1.001-1.070) and statistical significance (\(p\) = 0.041) where the risk increased with patients with high rate of tobacco consumption (\(>\)40 pack years). Approximately 56.3% of all the participants (n = 269) were non-drinkers (125 patients of TG (52.3%) and 144 patients of CG (60.3%). The wine was the most frequent alcohol beverage in 185 patients (38.7%) (Table 3). The average alcohol consumption in TG was 7.4 drinks/week and in CG it was 3.7 drinks/week. Among the drinkers, it was observed that the alcohol consumption amount was 1 drink per day or less (\(\leq\)7 drinks/week) in 86 patients (41.2%) and the alcohol consumption was 2 drinks per day (14 drinks/week) in 62 patients (29.7%), while the alcohol consumption in the rest (n = 61) of drinkers (29.1%) was more than 2 drinks per day. The presence of a history of alcohol abuse was observed in 12 patients of the TG (5%). The calculated ORs for tobacco and alcohol are presented in Table 4. Drinker patients showed a significant associated risk of developing OSCC (\(p\) = 0.05) and with OR = 1.035 (95% CI 1.010-1.061). No significance was observed in regard to the alcohol consumption amount. However, it was observed that the OR increase with the increase of alcohol consumption amount as the OR was 0.941 (95% CI 0.615-1.437) in patients who drink \(<\)7 drinks/week (\(p\) = 0.777), the OR increased to 1.021 (95% CI 0.359-2.905) in patients who drink 7-10 drinks/week (\(p\) = 0.969) and a further increase of the OR to 1.051 (95% CI 0.989-1.116) was observed in patients who drink \(>\)10 drinks/week (\(p\) = 0.111).