Int. J. Oral Maxillofac. Surg. 2 0 0 5 ; 34 ( S u p p l e m e n t 1): $ 1 - $ 1 8 1
32 5 keratocysts, with mean follow-up of 24 months. Treatment consisted of enucleation or enucleation/Carnoy's. There were 4 cases of basal cell nevus syndrome with multiple, recurrent keratocysts. The mean follow up was 57 months. These lesions were treated with enucleation or enucleation/cryotherapy. There was one recurrence of mandibular CGCG which was subsequently managed with alpha-interferon; there is no recurrence to date. There was one surgical complication, in which the bone graft failed to integrate. In six cases, there were residual V3 neurological deficits at the latest follow-up. Five cases were reconstructed with bone grafts, and one case was reconstructed using distraction osteogenesis. Patients with locally aggressive multilocular radiolucent lesions were successfully treated with combination therapy of surgical enucleation with chemical ablation, with a tendency for larger lesions to be treated with wide excision. In cases of extensive CGCG, alpha-interferon was used as adjunctive therapy to decrease the size of lesion.
INFLUENCE OF POST-RADIATION DENTAL EXTRACTIONS ON THE INCIDENCE OF OSTEORADIONECROSlS OF THE JAWS
B. Nierzwicki, J. Kadyszewska. Department of Oral and Maxillofacial
Surgery Medical University of Gdansk, Gdansk, Poland The objective of this study was to assess the influence of dental postradiation extractions on the incidence of osteoradionecrosis of the jaws within the study group and in the reviewed literature. Its aim was also to identify the predisposing risk factors in the development of osteoradionecrosis and to assess the incidence and severity of other coexisting complications during the radiation therapy of malignant tumors located in the oral cavity, face and neck. The study group consisted of 59 patients treated at the Department of Oral and Maxillofacial Surgery at Medical University of Gdansk between 1994 and 2000, that underwent postradiation dental extractions. The time between completion of radiotherapy and commencement of extractions, number of teeth extracted, number of bone exposures and treatment methods were recorded. The influence of post-radiation extractions on the incidence of osteoradionecrosis of the jaws was assessed between 12 months and 5 years after the first extraction. Osteoradionecrosis was diagnosed in 11 (26.83%) patients, after a total of 46 extractions: 39 in the mandible and 7 in the maxilla. Thirteen out of 89 (14.61%) extractions led to the development of osteoradionecrosis. In this group of 89 extractions, 29 (32.58%) were performed on patients with therapeutic absorbed radiation dose in the range between 6500 and 7000cGy. The study revealed that postradiation dental extractions led to a high incidence osteoradionecrosis of the jaws in the patients within the study group, and the total absorbed radiation dose was the most important predisposing factor. There was no statistically significant relation between the patients' age, time elapsed from termination of radiotherapy to commencement of extractions, number of teeth extracted and the type of extraction (single vs. multiple) and the incidence of osteoradionecrosis of the jaws. The results of the study and literature review led to the conclusion that prevention is the most judicious approach to this serious complication.
[-O-'~-~ ACTINOMYCES IN INFECTED OSTEORADIONECROSIS A PREVIOUSLY OVERLOOKED PATHOGEN? M. Kunkel 1 , T. Hansen 2, C.J. Kirkpatrick 2, A. Weber 2, W. Wagner 1 .
1Department of Oral and Maxillofacial Surgery, 2 Institute of Pathology, Johannes Gutenberg-University Mainz, D-55101 Mainz, Germany Infected osteoradionecrosis (IORN) is a severe complication of radiation therapy for head and neck cancer. IORN can lead to extended osseous destructions and often requires subsequent major resections. We show that Actinomyces is considerably more frequent in IORN than previously demonstrated. The study population consisted of 31 patients (7 female, 24 male; median age: 58.3 years). All patients exhibited clinical and radiological signs of IORN (infection, mucosal or skin fistula, and sequestrated bone). To detect Actinomyces colonies, histological examination was performed by using several stainings (H&E, Gram, Grocott, PAS). We found prominent Actinomyces colonies in 20 of 31 patients (64.5%). The majority of these lesions were localized in the mandible (16/20). Most interestingly, Actinomyces were almost exclusively found in conjunction with necrotic bone, but were very rarely detectable in the soft tissues adjacent to the fistulae. Since Actinomyces were almost exclusively detected in the necrotic bone tissue exhibiting signs of erosion, it seems likely that these microorganisms are not only a contaminant but are
involved in the bone degradation and thus may play a relevant role for the pathogenesis of IORN.
[-G'~-.'~ RHABDOMYOSARCOMAS LOCATED IN OMF REGION D. Gogalniceanu, M. Badaluta, G.D. Mihalache, E. Laba, O. Lupascu.
University of Medicine and Pharmacy "Gr. T. Popa", lasi, Department of Oral and Maxillofacial Surgery, Romania Introduction: Rhabdomyosarcoma is a rare malignant tumor, extremely aggressive, with an infiltrative evolution, most common in children and young adults. Modern investigation techniques lead to a correct diagnosis, a better prognostic and improved therapeutic protocols in rhabdomyosarcomas. Aim: The authors wish to exemplify the rarity of this type of malignant tumor, which has a high rate of recurrence and is very serious, and difficulties of diagnosis and treatment. Nine patients were diagnosed with rhabdomyosarcoma in OMF region and treated between 1993 and 2004. Their age was between 8 and 76, (66% between 8 and 34), 4 males and 5 females. The location of the tumor was, according to its frequency, in parotid region, maseteric region, buccal region, temporal region, zygomatic fossa and maxilla. Anatomopathological diagnosis was: 2 cases of embrionar rhabdomyosarcoma, 2 cases of alveolar rhabdomyosarcoma, 1 case of pleomorf rhabdomyosarcoma and 3 cases of unusual rhabdomyosarcoma. Only 7 patients were operated, and had post operative chemotherapy, the other 2 had chemotherapy after biopsy. 3 patients did not follow up the post operative examination. One female patient died in a few months because of several metastases. 2 children with post operative chemotherapy died 2 years later. 3 patients operated in the last year are still alive under cytostatic treatment. Clinical experience shows that rhabdomyosarcoma is a rare but possible tumor in OMF region. Because of its aggresiveness, the tumor must be treated with a multimodal therapy. The results of the therapy are poor and the prognostic is uncertain, because of frequent recurrence and on distance metastasis, followed by exitus.
F - G - ~ - ~ FIBROUS HISTIOCYTOMAS IN OMF REGION-CLINICAL AND THERAPEUTICAL STUDY
G.D. Mihalache, D. Gogalniceanu, C. Vicol, D. Negru, E. Laba, O. Lupascu. University of Medicine and Pharmacy "Gr. T. Popa" lasi,
Romania Department of Oral and Maxillofacial Surgery, Romania Introduction Fibrous histiocytoma is a benignant or malignant tumor, made by fibroblasts and multinuclear histiocyte like cells. Characteristic for the benignant type (BFH) is the presence of fibroblasts, mono and multinuclear cells, some of them with great lipidic mass. In advanced lesions the tumor is named xanthoma or fibroxanthoma. It is located in the iliac bone, ribs, long bones, and cranial bones, with a great recurrence rate. Malignant fibrous histiocytoma (MFH) described for the first time by O'Brien and Stout in 1960, is a sarcoma with fibroblasts, myofibroblasts and giant histiocyte like cells, disposed in storiform. MFH is located in long bones (tibia and femur), and in very few cases in membrane bones, like mandible. Aim The authors wish to emphasize the rare presence in OMF region of the fibrous histiocytomas, which are diagnosed by clinical and imagistic examinations being confirmed by anatomopathological and immunohistochemical exams, and to point out the necessity of radical extirpation of the tumor, followed by radiotherapy or chemotherapy. In the last 10 years in OMF Clinic in lasi (1994-2004), we had 6 patients diagnosed with fibrous histiocytoma: 3 patients with BFH and 3 with MFH. Four were males and two were females. BFH was located in buccal region, maseteric region and palatine region. MFH was located in mental region, maxillary sinus, buccal region, zygomatic fossa, with submental and submandibular metastasis in one case. Two cases of MFH were operated; in one case biopsy was taken and chemotherapy followed. In BFH cases the resections were wide, and there were no recurrence. In MFH cases the resections were wide also, at a distance, followed by chemotherapy. The cases that were operated have been followed up, and there is no metastasis or recurrence. BFH and BFH are aggressive tumors, which must be resected widely, radically, a fact that prevents recurrence. Postoperative chemotherapy and strict follow up of the patients raise the life expectancy in fibrous histiocytoma cases.