Expansive Nasopalatine Duct Cysts with Nasal Involvement Mimicking Apical Lesions of Endodontic Origin: A Report of Two Cases

Introduction: The nasopalatine duct cyst (NPDC) is the most frequent nonodontogenic cyst of the jaws and can be misinterpreted as an apical lesion of endodontic origin. Methods: In the first case, a 17-year-old male patient was referred because of a pressure sensation in the anterior maxilla. The teeth #7, #8, #10, and #11 responded to cold sensitivity testing, and on tooth #9 an endodontic treatment had been performed 3 years ago. Only periapical radiographs had been taken, and a radicular cyst was suspected. In the second case, a 42-year-old man reported inconvenience wearing his upper removable partial denture. Suspecting a jaw cyst in the anterior maxilla, the general dental practitioner referred the patient. Results: Limited cone-beam computed tomography scans visualized the expansion of the cysts and the involvement of the neighboring structures in both cases. In both patients, the NPDCs were treated first by marsupialization in local anesthesia and second with cystectomy in general anesthesia with reconstruction of the defect areas with bone gained from the iliac crest. The final diagnosis was achieved by histopathological examination. Conclusions: If not diagnosed early, the NPDC can expand through the palatal and/or buccal cortical wall and also into the nasal cavity. The more expansive the NPDC is becoming, the more complex the final diagnosis is and the subsequent surgical therapy. (J Endod 2011;37:1320-1326)