Final answer:
Smokeless tobacco keratosis is characterized by hyperkeratosis, acanthosis, and dysplasia in the oral mucosa due to tobacco usage.
Step-by-step explanation:
Smokeless tobacco keratosis refers to the changes in the tissues of the oral mucosa caused by the use of smokeless tobacco products. The histopathologic features typically include hyperkeratosis, acanthosis, and dysplasia. Hyperkeratosis refers to an excessive presence of keratin, acanthosis is an increase in the thickness of the spinous cell layer, and dysplasia denotes abnormal cellular changes. These changes are commonly observed in the oral mucosa of individuals who regularly use smokeless tobacco products.