A patient presents with a firm, smooth, pink, sessile nodule on the buccal mucosa that is asymptomatic and has been present for several years. Based on clinical features, what is the most likely diagnosis?

Fibromas (irritation fibromas or traumatic fibromas) are the most common benign soft tissue tumors of the oral cavity. They present as firm, smooth, well-defined, pink or normal-colored nodules, typically sessile or pedunculated, and are most common on the buccal mucosa along the occlusal line. They result from chronic low-grade trauma or irritation, are asymptomatic, and do not change in size significantly over time. Pyogenic granulomas are soft, red, and bleed easily; mucoceles are soft and bluish; and squamous cell carcinoma presents with irregular, indurated, ulcerated lesions.