A patient presents with a single, asymptomatic soft-tissue nodule on the buccal mucosa with a smooth surface and normal pink color, consistent with chronic trauma from cheek biting. What is the most likely diagnosis?

The traumatic fibroma (also called irritation fibroma) is the most common soft-tissue tumor-like lesion in the oral cavity. It is a reactive hyperplasia of fibrous connective tissue in response to chronic local irritation (cheek biting, denture flanges, or other trauma). It presents as a smooth-surfaced, firm, pink-colored nodule, most commonly on the buccal mucosa along the occlusal line. It is asymptomatic and does not recur after simple excision. Papilloma is typically exophytic with a cauliflower surface texture. Pyogenic granuloma is highly vascular and bleeds easily. Monomorphic adenoma is a salivary gland tumor.