Comparing Clinical and Radiographic Characteristics of Chronic Diffuse Sclerosing Osteomyelitis and Craniofacial Fibrous Dysplasia in the Mandible.

Differential diagnosis of chronic diffuse sclerosing osteomyelitis of the mandible (DSOM) and craniofacial fibrous dysplasia (CFD) involving the mandible is challenging. The purpose of this study was to explore the differences of the clinical and radiographic characteristics between these 2 conditions. In this retrospective cross-sectional, blinded, comparative study, clinical and imaging data of patients with DSOM and CFD at the Peking University Hospital of Stomatology from 2012 to 2018 were retrieved. Clinical characteristics, mainly pain, swelling, and trismus, and radiographic findings, including sclerosis, lysis, and subperiosteal bone formation, were evaluated. The t test, χ2 test, and Fisher-Freeman-Halton test were used to determine differences. Thirty-seven patients with DSOM and 32 patients with CFD were included (mean ages, 24.2 and 28.4 years, respectively); both groups showed a female predilection. DSOM (91.9%) and CFD (84.4%) were mainly unilateral. Patients with DSOM mainly presented with pain (94.6%), soft-tissue swelling (100.0%), and trismus (54.1%), whereas those with CFD did not experience pain (90.6%) and showed bone enlargement (87.5%) without trismus (6.3%). Panoramic radiographs and computed tomography scans of patients with DSOM showed subperiosteal bone formation, cortex lysis, and poorly demarcated cortex, whereas those patients with CFD mainly showed moderate-to-severe bone expansion, well-demarcated cortex, and tooth and mandibular canal displacement. These findings emphasize the importance of clinical and radiographic features in differentiating between DSOM and CFD. Pain, soft-tissue or bone-tissue swelling, subperiosteal bone formation, clarity of the boundary of the cortex and medulla, and continuity of the cortical bone are key points facilitating differentiation.