OBJECTIVE: This study investigated whether temporomandibular joint (TMJ) condyle-fossa relationships are bilaterally symmetric in class III malocclusion patients with and without asymmetry and compared to those with normal occlusion. The hypothesis was a difference in condyle-fossa relationships exists in asymmetric patients. METHODS: Group 1 comprised 40 Korean normal occlusion subjects. Groups 2 and 3 comprised patients diagnosed with skeletal class III malocclusion, who were grouped according to the presence of mandibular asymmetry: Group 2 included symmetric mandibles, while group 3 included asymmetric mandibles. Pretreatment three-dimensional cone-beam computed tomography (3D CBCT) images were obtained. Right- and left-sided TMJ spaces in groups 1 and 2 or deviated and non-deviated sides in group 3 were evaluated, and the axial condylar angle was compared. RESULTS: The TMJ spaces demonstrated no significant bilateral differences in any group. Only group 3 had slightly narrower superior spaces (p < 0.001). The axial condylar angles between group 1 and 2 were not significant. However, group 3 showed a statistically significant bilateral difference (p < 0.001); toward the deviated side, the axial condylar angle was steeper. CONCLUSIONS: Even in the asymmetric group, the TMJ spaces were similar between deviated and non-deviated sides, indicating a bilateral condyle-fossa relationship in patients with asymmetry that may be as symmetrical as that in patients with symmetry. However, the axial condylar angle had bilateral differences only in asymmetric groups. The mean TMJ space value and the bilateral difference may be used for evaluating condyle-fossa relationships with CBCT.
Cone-Beam Computed Tomography ; Facial Asymmetry ; Humans ; Malocclusion* ; Mandible ; Retrospective Studies* ; Temporomandibular Joint

Malignant ectomesenchymoma is a rare tumor originating from remnants of migratory neural crest(ectomesenchyme) and composed of neuroectodermal as well as mesenchymal components. Neuroblasts and ganglion cells constitute the neuroectodermal components and rhabdomyosarcoma is the most frequently encountered mesenchymal components. We report a case of malignant ectomesenchymoma in a two-month-old boy who was presented with abdominal pain and urinary difficulty. The tumor appeared to arise from the prostatic region and enlarged to compress the bladder leading to bilateral hydronephrosis. Immunohistochemical studies for the resected tumor confirmed the presence of mixed ganglioneuroma and rhabdomyosarcoma establishing the diagnosis of malignant ectomesenchymoma. However, in the initial biopsy specimen of tumor, poorly differentiated round to oval cells positive for both desmin and vimentin staining were uniformly noted and the incorrect diagnosis of rhabdomyosarcoma was made. Intensive multi-agents chemotherapy, surgery and radiotherapy had failed in preventing the development of local recurrences. Subsequently, invasion of pubic bone and lung metastases ensued. This report enlightens the need for immunohistochemistry to seek possible neuroectodermal components in a tumor specimen suggestive of rhabdomyosarcoma.
Abdominal Pain ; Biopsy ; Desmin ; Diagnosis ; Drug Therapy ; Ganglion Cysts ; Ganglioneuroma ; Humans ; Hydronephrosis ; Immunohistochemistry ; Lung ; Male* ; Neoplasm Metastasis ; Neural Plate ; Pubic Bone ; Radiotherapy ; Recurrence ; Rhabdomyosarcoma ; Urinary Bladder ; Vimentin