Leukoplakia is a whitish patch or plaque that cannot be characterized, clinically or pathologically, as any other disease and it is not associated with any physical or clinical causative agent except the use of tobacco (The International Symposium, 1983) Department of Oral Pathology, Shandong UniversityDepartment of Oral Pathology, Shandong University 4  Leukoplakia is a whitish patch or plaque that cannot be characterized, clinically or pathologically, as any other disease and it is not associated with any physical or clinical causative agent except the use of tobacco. (The International Symposium, 1983)