Infected Dentigerous Cyst With Extraoral Fistula in a Child.

Dentigerous cysts are the most common developmental odontogenic cysts. Still, a secondarily infected dentigerous cyst in children that results in an extraoral fistula is rare and can present as a routine odontogenic abscess. In this paper, we present a case of a healthy 10-year-old girl with progressive pain, swelling, and purulent discharge of the left mandibular area documented for one month after outpatient antibiotic treatment. Clinical examination showed a fluctuant facial swelling with an external fistula, while CT revealed a well-defined unilocular cystic lesion with an unerupted mandibular second premolar. The patient was treated with surgical enucleation of the cyst, extraction of the retained second molar and premolar, and excision of the external fistula. The wound culture grew Prevotella oris, which informed appropriate anaerobic antibiotic therapy. The cyst was histopathologically proven to be an inflamed dentigerous type. The patient had an uneventful postoperative course and made a complete clinical recovery. This case illustrates the value of early imaging, culture-specific antibiotics, and surgical treatment in children with prolonged jaw swelling or recurrent dental infections to minimize morbidity and mortality.