P.043 Mandibular condyle and infratemporal fossa reconstruction using vascularized iliac crest and vascularized calvarial bone graft

Posters Trenaunay. He presented with a clearly visible hypertrophy of the maxilla, gingiva and mucosa of the lower lip. The right leg had a bigger circumference and was 3 cm larger than the left leg. He had port wine stains on 75% of the body. The facial vascular malformations were localised in the second and third distribution area of the trigeminal nerve. Surface rendered 3D images demonstrated an osteohypertrophy of the calvarium, the processus alveolaris of the maxilla bilateral, the right ala maior os sphenoidale and the right os zygomaticum. This was also demonstrated by abnormal values of the distances between the centroids of the canines and premolars, based on the chronological age. These oromaxillofacial anomalies resulted in spacing, a large sagittal and transversal overbite due to the macromaxilla and a neutro-occlusion in the molar zone According to the literature, osteohypertrophy in andgiodysplastic syndromes, can be considered as a consequence of vascular malformations on the periosteum level. Others wondered if the skeletal alterations might be primary to an embryologic malformation with genetic factors. P.043 Mandibular condyle and infratemporal fossa reconstruction using vascularized iliac crest and vascularized calvarial bone graft W. Nam, S.-H. Kang, Woong Nam, I.-H. Cha, S.-W. Chung, S.-K. Choi, H.-J. Kim. Department of Oral and Maxillofacial Surgery, College of Dentistry, Yonsei University, Seoul, Republic of Korea Objectives: In cases of tumor growth in the infratemporal fossa (ITF) and mandible, there are some difficulties in approaching and removing the lesion during surgery as well as in reconstruction after surgery on account of its anatomical location. In particular, protection of the dura and a functional and aesthetic reconstruction of the defective skeleton of the skull and mandible are required. The prevention of Cerebrospinal fluid (CSF) leakage and Intracranial infection should be considered during a reconstruction of the dura, and it is important to prevent the mandibular condyle from being invaginated into the skull. For a vascularized calvarial bone flap, the level of bone resorption is lower, and the fascia is suitable for reconstructing the dura, with less likelihood of infection. In case of a reconstruction covering the mandible, a bone flap may protect the skull and function as a joint region for the mandible. Fibula, scapula, and iliac bone flaps are generally used for a mandible reconstruction, and in the case of a mandible reconstruction linking ITF, care should be taken to prevent excessive force of mandible from being imposed on the ITF, allowing for the functions of the lower jaw, such as mastication, and considering the aesthetic aspect of the reconstruction. Therefore, in order to make it easier to protect the reconstructed ITF and activate the functions of the lower jaw, the fascia in the ITF reconstruction in this case was the intracranial dura. The divided bone of a vascularized calvarial bone flap was fixed toward the outside. The lower jaw was reconstructed with a deep circumflex iliac artery musculoosseous flap, and the region contacting the ITF was covered with internal oblique muscle in the area functioning as the condylar part of the posterior attachment. P.044 Mandibular eosinophilic granuloma in a 20 month-old child P. Novak1 , K. Bartyik2 , I. Nemeth3 , L. Seres1 . 1 Department of Oral and Maxillofacial Surgery and Oral Medicine, University of Szeged, 2 Department of Peadiatrics, University of Szeged, 3 Department of Pathology, University of Szeged, Hungary Objectives: Langerhans’ cell histiocytoses are the group of rare diseases that involve histiocytes, which are derived from bone marrow stem cells. Eosinophilic granuloma is a benign and

Benign lesions of the facial bones

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localized disease and accounts for approximately 60−70% of Langerhans’ cell histiocytosis. About 50% of all bone lesions occurs in the skull and the facial bones. It commonly affects children and young adults. Methods: We report an unusual case of a twenty month old female baby referred to our service with a local swelling on the right side the mandible. Personal history was unremarkable for any previous infections or disease condition. Computed tomography demonstrated an irregular radiolucency with a diameter of approximately 35 mm that destroyed the mandible from the angle to the condyle. The possible differential diagnoses were osteosarcoma, Ewing sarcoma and osteomyelitis. Histopathological examination showed that the tumor was composed of a polymorphous infiltrate including histiocytes, leukocytes, and Langerhans cells with abundant cytoplasm and grooved nuclei. The tissue specimen stained strongly for CD1a and S100 protein. Results: Based on the histopathologic and immunohistochemical findings, the diagnosis of eosinophilic granuloma was made. Corticosteroid therapy was initiated. The lesion has been asymptomatic for 10 months. Conclusions: Eosinophilic granuloma at this age is extremely rare. Although the prognosis is good, mandibular defect reconstruction and correction of the mandibular growth rise difficult questions. P.045 Method to evaluate the effects fo treatment for osteoradionecrosis I. Niedzielska, M. Je˛drusik-Pawłowska, R. Markiewicz. Silesian Medical University, Katowice, Poland, Tychy, Poland Objectives: The aim of the poster is to present the results of conservative treatment for osteoradionecrosis of the mandible with HBO support, and to assess the usefulness of thermal imaging in ORN remission monitoring. Methods: Four patients of the Department of CranioMaxillofacial Surgery, Silesian Medical University in Katowice were recently treated for progressive osteoradionecrosis of the mandible and received HBO as an adjunct to conservative therapy. Treatment effects were assessed based on the results of clinical, radiological and thermographic examinations. Thermographic images were obtained before and after treatment in a hyperbaric chamber. Results and Conclusion: Thermography confirmed improvement in the patients’ clinical condition following HBO. P.046 Odontogenic myxoma – a case series and surgical management Y. Leiser, I. Abu-El-Naaj, M. Peled. Department of Oral and Maxillofacial Surgery, Rambam, Haifa, Israel Background: Odontogenic myxoma is a benign, locally invasive and aggressive, nonmetastasizing neoplasm of the jaw bones. It is the second most common odontogenic lesion with incidence of approximately 0.07 new cases per million people per year. Despite the benign nature of these lesions, there is a high rate of local recurrence after curettage alone and usually requires adequate resection. Purpose: the purpose of the present study is to review current literature on odontogenic myxoma surgical treatment and reconstruction possibilities, and to present 3 different cases and discuss the surgical and reconstructive possibilities available to the oral and maxillofacial surgeon. Patients: Three patients are presented and discussed, two had maxillary odontogenic myxoma that were treated differently according to the tumor behavior and progression and one case of mandibular odontogenic myxoma is also discussed. Conclusion: locally aggressive odontogenic myxomas should be treated according to the size and behavior of the tumor. We believe that due to the high recurrence rates of these lesions,