A Case of an External Dental Fistula Originating from a Retained Tooth Fragment in the Edentulous Maxilla.

An external dental fistula is a skin perforation caused by spontaneous drainage of pus from odontogenic lesions and is often misdiagnosed due to its resemblance to other conditions. This report describes an 84-year-old man who presented with left cheek swelling and pus drainage. Although an external dental fistula was initially suspected, the diagnosis was delayed due to the edentulous state of the left maxilla. After multiple referrals to various specialties and several misdiagnoses, a computed tomography scan revealed a fistulous tract linked to a retained tooth fragment. The dental fragment was surgically removed, leading to resolution of the abscess and closure of the fistula. This case highlights the importance of considering external dental fistulas even in edentulous patients, as a retained tooth fragment can be the underlying cause.