Cartilaginous choristoma of the gingiva

Cartilaginous choristomas of the gingiva are rare lesions. These lesions can derive from metaplastic osseous or chondroid formation, stimulation of cartilaginous embryonic rests, pluripotent cells, development of a mixed tumor with predominance of osseous tissue or cartilage, other neoplasms and teratomas with preponderance of bone and cartilage. A 60-year-old male was referred for diagnostic evaluation of a nodule involving the adherent gingiva of the maxillary premolar region, present for about 6 months and extending into the vestibular mucosa. Microscopically, the overlying mucosa was acanthotic; the submucosal mass was composed by mature cartilage. Neither nuclear atypia nor mitoses were evident. In some areas, the chondrocytes appeared to be surrounded by dense connective tissue (pseudo-capsule). The diagnosis was cartilaginous choristoma. There was no evidence of recurrence at 2 years follow-up. The treatment of oral choristomas consists of a simple excision.