Most common antecedent of erythroplakia and leukoplakia is-

ETIOLOGY. The etiological factors are similar to those suggested for carcinoma of the oral mucosa (discussed below). It has the strongest association with the use of tobacco in various forms, e.g. in heavy smokers (especially in pipe and cigar smokers) and improves when smoking is discontinued, and in those who chew tobacco as in paan, paan masala, Zarda, gutka, etc. The condition is also known by other names such as smokers keratosis and stomatitis nicotina. Other etiological factors implicated are chronic friction such as with ill-fitting dentures or jagged teeth, and local irritants like excessive consumption of alcohol and very hot and spicy foods and beverages. Ref: TEXTBOOK OF PATHOLOGY 6th EDITION - HARSH MOHAN PAGE NO:525