Calcifying odontogenic cysts: A 20-year retrospective clinical and radiological review.

Objective: Calcifying odontogenic cysts (COCs) exhibit diverse clinical behaviours and may be associated with other benign odontogenic tumours. In this study, the clinical and radiological features of COCs were analysed according to subtypes based on the classification by Praetorius et al. Emphasis was placed on cases exhibiting atypical or aggressive radiological appearances. This information may assist the clinician to better understand the radiological spectrum of COCs.

Methods: Histologically confirmed cases of COCs were retrospectively reviewed in a 20-year period from three tertiary institutions. The following clinical information was reviewed: patient demographics, main complaint, clinical duration, anatomical site and detailed radiological features.

Results: Twenty-seven cases of COCs were included in the study. Asymptomatic swelling was the main clinical presentation with infrequent reports of associated pain. COCs had an anterior mandibular predilection. Well-demarcated borders were seen in all cases with isolated cases showing focal areas with loss of demarcation. Unilocular lesions were more common than multilocular variants. Internal calcifications were frequent and six cases presented with associated odontomas. Maxillary COCs resulted in the displacement of the maxillary sinus and/or nasal cavity walls. Radiological signs of aggression, including cortical destruction, were noted in a few cases.

Conclusion: Given the fact that COCs can present with a spectrum of clinical behaviours and radiological presentations, the academic debate regarding the cystic versus neoplastic nature of the entity is justifiable. The cases in the current sample presented with diverse presentations, ranging from indolent to lesions with significant growth and aggression.