Aim: The Myofibroma (MF) is a benign mesenchymal tumor frequently observed in the skin and subcutaneous tissue of the head-neck region. It is described mainly in infants with congenital forms and, in early childhood, with acquired forms. Less often, it can be observed in adolescents and adults. The location of a MF in the oral cavity is occasional and differential diagnosis must be established with other benign and malignant neoplasms, high or low grade, of the oral mucosa. The histology of the myofibroma shows a biphasic growth pattern: elongated spindle cells with eosinophilic cytoplasm, in the borders, polygonal cells arranged in a palisading pattern, with hyperchromatic nuclei, in the central portions. The diagnosis of MF, usually made after excision of the neoformation, is obtained by means of immunohistochemistry, in which there is positivity for vimentin and αactine smooth muscle antibodies and negativity for keratin, S-100, EMA (Epithelial Membrane Antigen) antibodies. The treatment is surgical; the prognosis is generally good with low rates of recurrence after excision.
Case report: The authors describe a case of MF in a 16-year-old male subject, that came to their observation for the growth of a considerable mass attached to the gingival mucosa, describing the therapeutic strategy.