Impacted Maxillary Canine Associated Cyst: Keratocyst?

Aim:
Odontogenic keratocysts (OKCs) are benign but locally aggressive odontogenic lesions with a high recurrence rate. They are most commonly found in the posterior mandible, particularly in non–tooth-bearing areas. This case report describes an unusual presentation of an OKC associated with an impacted maxillary canine.

Case:
A 13-year-old female was referred for management of a Class II Division 2 malocclusion on a skeletal Class II base, complicated by an impacted upper right canine (UR3). Radiographic examination revealed a cystic lesion associated with the impacted tooth. The lesion was initially diagnosed as a dentigerous cyst, and the patient was referred for extraction of the UR3, enucleation of the cyst, and extraction of the upper right primary canine (URC) and upper left first premolar (UL4).

Management:
The procedure was carried out under general anaesthesia. Histopathological examination of the excised lesion confirmed the diagnosis of an odontogenic keratocyst. The patient was reviewed annually with serial panoramic radiographs for four years. Imaging demonstrated progressive bone infill and no evidence of recurrence. Orthodontic treatment commenced seven months after surgery and was completed uneventfully.

Discussion:
OKCs can mimic more common and less aggressive odontogenic cysts. In this case, the lesion presented as a well-defined unilocular radiolucency surrounding an impacted tooth, closely resembling a dentigerous cyst. This is an atypical presentation, as OKCs are usually located in the posterior mandible and may expand within the medullary bone with minimal clinical signs.

Conclusion:
Clinicians should be aware of the atypical presentation of OKCs and include them in the differential diagnosis of cystic lesions associated with impacted teeth. Accurate diagnosis is essential, as management and follow-up differ significantly from other odontogenic cysts, helping to reduce the risk of recurrence.