Idiopathic noncondylar hemimandibular hyperplasia.

A female patient with 'idiopathic non-condylar hemimandibular hyperplasia' was followed from the age of 7.5-11.5 years. This rare disorder was characterised by an increase in volume of the right inferior ramus and mandibular body. It also included accelerated development and eruption of the teeth on the affected side, but no indication of enlargement of the condyle or the condylar neck. To date, review of the literature revealed several cases of hemimandibular hyperplasia and unilateral condylar hyperplasia, both of which present with enlargement of the condyle. However, the patient differed significantly from any previously reported cases, since she had no enlargement of the condyle. The above mentioned patient also differed from patients with hemihypertrophy, since the teeth were accelerated in development, but not hyperplastic. In addition, from histopathologic and radiographic examinations, as well as an angiogram, benign fibro-osseous and vascular lesions of the mandible were excluded. Although this is a single case report and neither the aetiology nor the pathogenesis is yet understood, it may suggest a new disorder of the mandible. Therefore, future reporting of similar cases should be encouraged.