The lining of the mouth is the oral mucosa, and the presence of small contiguous granules on the oral mucosa may be lichen planus, as described below. Lichen planus is a linear white or grayish-white pattern of small papules, which can be reticulate, dendritic, annular or semi-annular, plaque-like, etc. The pattern is often symmetrical and can occur anywhere on the oral mucosa. The lesions are often symmetrical and can occur in any part of the oral mucosa. The mucosa in the lesion area can be normal, or there can be congestion, vesicles, ulcers, atrophy, blisters and so on. The lesions of lichen planus may have roughness, wood astringency, and localized pain due to stimulation when eating spicy, hot, sour, salty food. There may be other reasons for the appearance of small, contiguous granules on the oral mucosa, and it is recommended to visit the hospital in time to receive professional treatment.