The fibroma, also referred to as irritation fibroma, is by far the most common of the oral fibrous tumorlike growths. While the terminology implies a benign neoplasm, most if not all fibromas represent reactive focal fibrous hyperplasia due to trauma or local irritation. Although the term focal fibrous hyperplasia more accurately describes the clinical appearance and pathogenesis of this entity, it is not commonly used.
A fibroma may occur at any oral site, but it is seen most often on the buccal mucosa along the plane of occlusion of the maxillary and mandibular teeth as depicted below. It is a round-to-ovoid, asymptomatic, smooth-surfaced, and firm sessile or pedunculated mass. The diameter may vary from 1 mm to 2 cm. The surface may be hyperkeratotic or ulcerated, owing to repeated trauma.
Fibroma of the left buccal mucosa in a 44-year-old man.
Fibromas are most often observed in adults, but they may occur in individuals of any age and either sex.
The clinical differential diagnosis of a fibroma includes giant cell fibroma, neurofibroma, peripheral giant cell granuloma, mucocele, and benign and malignant salivary gland tumors (eg, see Salivary Gland Neoplasms).
Histologically, a fibroma is an unencapsulated, solid, nodular mass of dense and sometimes hyalinized fibrous connective tissue that is often arranged in haphazard fascicles. A mild chronic inflammatory infiltrate may be present. The surface epithelium may be hyperkeratotic, either hyperplastic or atrophic, and it may be ulcerated. Conservative excisional biopsy is curative, and its findings are diagnostic. Recurrence is possible, however, if the offending irritant persists.[1, 2]
Elastofibroma: The elastofibroma is a rare dermatologic pseudotumor most often seen in the subscapular region. Patients tend to be older than 50 years, and some studies show a female predominance. A single case of oral elastofibroma has been reported. A 56-year-old woman presented with an asymptomatic, 2-cm, firm, well-circumscribed mass in the floor of her mouth. The lesion was conservatively excised and had not recurred after a 2-year follow-up. Histologically, the elastofibroma consists of collagen fibers and coarse elastic fibers that can be demonstrated with elastin stain.[3, 4]
Sclerotic fibroma: The sclerotic fibroma was first described as a component of Cowden syndrome. It is an uncommon benign fibrous neoplasm that occurs most commonly in the skin and may be solitary or multifocal. Both sporadic sclerotic fibromas and those associated with the syndrome have also been described in the oral cavity, mainly in the buccal and labial mucosa. The tumor is a well-delineated but unencapsulated mass of densely collagenized, hypocellular fibrous tissue with a storiform pattern and prominent clefts between collagen bundles. The tumor cells are CD34 and vimentin positive.