Transient infantile lingual leukoplakia is a benign, self-limited condition in infancy characterized by gray-white plaques on the dorsal tongue. While the exact etiology of the condition is unknown, proposed mechanisms include the accumulation of retained epithelial cells due to infrequent oral friction prior to tooth eruption or, conversely, friction-induced epithelial hyperplasia from repetitive tongue contact with the hard palate. Supporting the friction-based hypothesis, concurrent sucking callouses on the upper lips have been found in some affected infants.

Reported cases have been noted to occur between ages 1 week to 7 months, with no observed sex or race / ethnicity predilection in a multicenter series from Germany, Canada, and Spain. The condition follows a self-limited course, with plaques resolving spontaneously, typically before age 1 year. Affected infants are otherwise healthy.