Unicystic Ameloblastoma and Odontogenic Keratocyst: Difficulty in Differential Diagnosis

Osteolytic pathologies of the jaws can be remarkably similar, regarding clinical, radiographic and histological aspects. Several of these lesions may be difficult to diagnose, and one example of it is the unicystic ameloblastoma (UA), which can mimic cysts, tumors, and bone dysplasia. This report presents and discusses a mandibular lesion with ameloblastoma features; however the preliminary diagnosis was odontogenic keratocyst (OKC). The second analyze, covering a larger area, shows epithelium projections to the lumen as well as ameloblastic island on mural structure, classifying it as Intraluminal/Luminal UA with Plexiform/Solid pattern and Focal Mural Involvement The five-year follow-up did not show recurrence. Due to the possibility of cellular transformation, the final diagnosis needs to be based on a second microscopy, which could cover a larger part of the lesion, in order to search for cell transformation areas.