Radiographic findings of odontogenic myxomas on conventional radiographs

Odontogenic myxoma (OM) is a rare tumour arising in the jaws. The tumour is believed to be of odontogenic origin due to the close relation to teeth. The radiographic appearance of OM is not specific and the diagnosis is frequently unexpected following surgical removal of the lesion. The aim of this study was to analyse the radiographic appearance of OM on conventional radiographs. This type of radiographic diagnosis is typically used by dental practitioners.

We studied panoramic radiographs and plain skull radiographs of 14 patients investigated over a period of 30 years (male: 3, female: 11; age at time of diagnosis: 8 to 45 years, ≤16 years: 3). The maxilla was affected in five and the mandible in nine patients. In each case, all tumour findings were restricted to one jaw.

Tumour size varied considerably. The largest tumours were seen in the distal parts of the mandible and ramus. Displacement of teeth was a frequent finding (8 cases), but root resorption was rare (2 cases). Honeycomb appearance on plain radiographs was associated with the size of the lesion and restricted to mandibular involvement.

The radiographic appearance of OM of the jaws varies considerably. Large lesions may exhibit characteristic radiological signs of a slowly growing lesion. However, discrete displacement of teeth associated with a small osteolytic zone of the alveolar process between two teeth can be an OM. Careful interpretation of conventional radiographs is a must in identifying early lesions.