Answer: Traumatized taste bud

Histology: The overlying surface epithelium shows intraepithelial taste buds that are not to be confused with pagetoid infiltration or dysplasia. The underlying mucosa demonstrates nests of squamous epithelium within a proliferation small nerve fibers set in a background of stromal fibrosis. The squamous cells are bland without atypia or mitotic activity. They maintain the lobular arrangement of nearby clusters of minor salivary glands.

Discussion: Intraoral taste buds are prone to traumatic injury. Trauma related changes of taste buds include a reactive atypia of the surface epithelium, stromal fibrosis, and proliferation of the small submucosal nerves akin to a traumatic neuroma. In the present case, these changes are seen in association with another trauma-related alteration – squamous metaplasia of the minor salivary glands. Although the presence of squamous nests in association with nerves may cause confusion with squamous cell carcinoma, these nests maintain the normal lobular distribution of minor salivary glands, lack cytologic atypia, and are associated with other trauma related changes. The findings in this case show significant overlap with the juxtaral organ of Chievitz, a non-neoplastic cluster of squamous cells often associated with myelinated nerves. This structure, however, is consistently located in the buccal temporal fascia along the medial aspect of the mandible (not the tongue).