2.2 Investigation and Differential Diagnosis
Orthopantomography (OPG) and cone beam computed tomography (CBCT) was
promptly ordered. They depicted a well-defined, multiloculated expansile
osteolytic lesion with few small septa spreading inside the lesion.
Expansion of the buccal cortex with areas of cortical destruction and
root resorption of mandibular left central incisor, right central and
lateral incisors were also noticed. The lesion measured 31.2 x 21.0 mm
extending from the left mandibular first premolar to the right
mandibular canine (Figures 2, 3). Radiographic preliminary differential
diagnosis included central giant-cell granuloma (CGCG), odontogenic
keratocyst (OKC), ameloblastoma, odontogenic myxoma, and
fibroameloblastoma.
An incisional biopsy was then conducted and the histopathological
specimen showed an irregular piece of soft tan-pink tissue with fragile
consistency. Cut sections demonstrated homogenous myxoid pink surface
containing hemorrhagic foci. The microscopic analysis revealed striated
muscle fibers, some reactive new and pre-existing bone trabecula and
presence of a neo-formed tissue composed of haphazardly arranged
stellate and spindle cells with no atypia in an abundant loose myxoid
stroma containing few collagen fibrils which was consistent with
histopathological features of odontogenic myxoma and therefore a
definitive diagnosis was made (Figure 4).