Objective: The aim of the study was an updated analysis of the frequency of leukoplakia in reference to tobacco smoking among the northern Polish population. Material and Methods: Medical records of 5720 patients who suffer from abnormalities and oral mucosa diseases between January 2015-December 2018 were analyzed. Among them, 416 medical charts of patients with leukoplakia were selected. The study group consisted of 196 women and 220 men aged between 21-86 years (average 45.6 years). The analysis was conducted in terms of age, gender, and smoking tobacco. The basic criterion for inclusion in the study was the presence of oral leukoplakia confirmed by histopathological examination, recorded in the chart. Information about the patient's active smoking was obtained from documented medical interviews. An active smoker was defined as a patient who smoked 10 or more cigarettes a day for at least the previous six months. The study used parametric and non-parametric statistical methods. Results: The highest incidence of leukoplakia was found in the age group 41-60 (46.6%), where the vast majority were active smokers (85.1%), and mostly men (86.2%). However, among patients with leukoplakia, the highest prevalence of smoking was found in the age group 21-40 years (86.8%) in women, where out of 38 patients with leukoplakia, 33 were active smokers. More patients with leukoplakia were observed in groups of smokers and it was statistically significant. Homogeneous form was the most commonly diagnosed form of leukoplakia in our study; it was found in almost 95% of cases. Leukoplakia was mainly observed on the cheeks. Changes on the gums, the alveolar process or the bottom of the tongue and mouth were rarely found. Conclusion: Our studies revealed that there is a statistically significant correlation between tobacco smoking and the presence of oral leukoplakia among the northern Polish population. It should be noted that dentists, in particular, are capable of early diagnosis and implementation of appropriate treatment of leukoplakia and, most often, crucial elimination of the main risk factor, which is smoking, and the implementation of effective tobacco control interventions.
Keywords: leukoplakia; precancerous lesions.