P.256 Experimental evaluation of platelet rich plasma (PRP) effect on bone healing

Posters Generally recommended method of treatment is surgical excision of tumour with the margin of unchanged tissues – resection, and the best results are reached when the first surgery is radical, because in the case of recurrence more extended procedure is required. Some authors consider that extended mandible resection conducted in all cases of ameloblastoma is too radical a procedure and postulate total removal of tumour using such conservative methods as enucleation which preserve continuity of mandible, especially in young people. Unfortunately less radical procedures as enucleation and marsupialization manifest with the high amount of recurrences reach nearly 100%. Some authors prefer enucleation as preliminary treatment in unicystic ameloblastomas. The authors refer 3 young patients with large ameloblastomas treated by enucleation. Two of them have completely bone regeneration and they are observed, one for 20 years and another for 6 years. The third patient is 6 months under control. The conservative management of ameloblastoma in young patients with long clinical and radiological follow-up can be an alternative method for destroying resection of the bone. P.253 The risk of adverse reactions following analgesic pharmacotherapy in oral and maxillofacial surgery T. Kaczmarzyk, J. Woron. Department of Oral Surgery, Medical College of the Jagiellonian University, Krakow, Poland Surgical procedures performed in maxillofacial region very often lead to post-operative pain that force patients to administer analgesics. Besides antibiotics, analgesics are the most commonly prescribed drugs by oral and maxillofacial surgeons. Moreover, this group of therapeutics has a very high risk of adverse reactions. Between May 1st, 2004, and February 28th, 2006, the Regional Centre for Adverse Drug Reactions in Krakow, Poland, received 46 reports of dangerous, analgesic-induced adverse reactions during pharmacotherapy in oral and maxillofacial surgical practice. Ketoprofen is the drug that most often lead to adverse reactions (22 reports), followed by mefanamic acid (10 reports), diclofenac (8 reports), piroxicam (3 reports), dexibuprofen (2 reports) and acemetacin (1 report). This paper describes possible adverse reactions resulting from analgesic pharmacotherapy in oral and maxillofacial surgical practice and how to prevent and treat them. P.254 Paraganglioma: Differential diagnosis with canalicular adenoma V. V´azquez Marcos, B. Garc´ıa-Montesinos Perea, R. S´anchez S´anchez, S. S´anchez Santolino. Servicio de Cirug´ıa Oral y Maxilofacial, Hospital Universitario Marqu´es de Valdecilla, (Santander), Universidad de Cantabria, Spain Introduction: The paraganglioma is an infrequent tumour derived from the neural crest. Most paragangliomas have a very rich blood suply. The parapharyngeal space (PPS) is their most common location. Canalicular adenoma is a rare benign salivary gland tumour of the oral cavity, tipically located in the upper lip and buccal mucosa and infrequently found on the palate. Histologically it is composed of columnar cells; the surrounding connective tissue stroma is often loosely arranged and vascular. Case report: A 54-year-old woman with a chief complaint of an inability to wear her upper denture, due to an enlarging mass on the right palate of 3–4 months duration. Clinically it was presented as a painless, slowly growing submucosal mass about

Oral medicine/Pathology 197 2 cm in size slightly fluctuant without bleeding or discharge. The covering mucosa was bluish colour. An axial-CT-scan showed a large well-circumscribed mass with vascular captain in the right soft palate. Head and neck arteriography revealed a hypervascular mass. After successful embolization, the tumor was excisioned and the resulting palatal defect was reconstructed with mucosal fat pad. The tumour mass was found to be well circumscribed, soft, dark tan in colour, and measuring 2.5×1.5×1 cm. The anatomopatologic diagnosis was canalicular adenoma of the palate. Discussion: The intricate vascular, neural and lymphatic structures of the PPS call for the differential diagnosis to include not only tumours originating in the PPS, but also tumours originated in adjacent structures, including palate. P.255 Avascular necrosis of the jaws: New therapeutic protocol in the treatment of 30 clinical cases A. Agrillo, M. Tedaldi, S.F.M. Marino, M.C. Mustazza. Department of Maxillo Facial Surgery (H.Dept. G. Iannetti), University of Rome “La Sapienza”. Rome, Italy Introduction: Osteonecrosis of the jaws has been increasingly reported in patients with bone metastasis from a variety of solid tumours and disseminated multiple myeloma receiving Bisphosphonates. Signs and symptoms that may occur before clinical evidence of osteonecrosis include changes of the health periodontal tissues, non-healing mucosal ulcers, loose teeth and unexplained softtissue infection. Materials and Methods: The authors developed a new protocol including the use of ozone therapy for the management of 30 patients showing osteonecrosis of the jaws following the use of Bisphosphonates. At presentation, each lesion was classified into small (< 1 c), medium (1–2 c), big (>2 c). Panoramic radiography and CT Dental Scan were obtained before starting procedures. Treatment consisted of local minor courettage and pre-, intra- and post-operative ozone therapy. All patients received antibiotic therapy, antiviral and antifungal therapy, ascorbic acid and chlorhexidine 0.2% mouthwash and oral anti-inflammatory drugs. This treatment was performed according to pre- and post-operative ozone application time. Results: After a period of 8 months of treatment, 18 patients (60%) had complete resolution of their starting clinical symptoms, 9 patients (30%) had partial improvement of their starting clinical symptoms. Only 3 patients (10%) had no improvement. Conclusions: According to our results, at present, ozone therapy, in association with mini-invasive surgical treatment and antibiotic, antifungal and antiviral drugs, seems most suitable choice for of avascular necrosis of the jaws. P.256 Experimental evaluation of platelet rich plasma (PRP) effect on bone healing A. Mocan1 , M. Yıldız1 , T. Oyg¨ur2 . 1 Oral and Maxillofacial Surgery, Ankara University Faculty of Dentistry, Ankara, 2 Pathology Department, Gazi University Faculty of Dentistry, Turkey The effect of PRP on bone healing had been evaluated experimentally in the study. Four standard in diameter of 3.3 mm bone defects were created on the left tibiae of 12 New Zealand white rabbits. Defects were grafted with PRP alone; b-TCP alone, and PRP and b-TCP in combination. Remaining defect was left empty as control groups. Animals were divided into 3 groups

198 Journal of Cranio-Maxillofacial Surgery 34(2006) Suppl. S1 based on their times of sacrifice. The rabbits were sacrificed in 14, 30 and 60 days. Tibiae were removed for histological evaluation. The quality of newly formed bone and the effect of PRP were evaluated by histological methods. The results showed no significant difference on 14th day. On the 30th day, the results showed an increase in both b-TCP alone group and PRP+b-TCP group. PRP+b-TCP group was greater than b-TCP alone group. No significant difference in bone formation was seen between the defects filled with PRP alone and control groups. On 60th day, bone formation seemed to be more effective when PRP was applied in comparison with b-TCP. In PRP+b-TCP group, bone formation was significantly greater than the other groups. The histological study revealed that the bone formation was more effective when PRP was used with synthetic bone substitue – b-TCP. PRP had positive effect on bone healing in rabbit tibiae models. P.257 Diagnosis and treatment of salivary glands tumour I. Raudjarv, M. Soots. Department of Maxillofacial Surgery, Tartu University Hospital, Estonia Introduction: Salivary gland neoplasms are uncommon and consist of less than 3% of oll tumours in the head and neck region. Despite the low tumour incidence, no organ system of the body produces such a large variety of neoplasms. Aims: The aim of this study was to analyse the diagnosis and results of treatment of tumours of the salivary glands operated in the Department of Maxillofacial Surgery of Tartu University Hospital during a 5 year period and to attempt to correlate the clinical and histopatological data with the prognosis and survival of the patients. Method: The study included 61 patients, treated over past 5 years from 2000 to 2005, in the Department of Maxillofacial Surgery of Tartu University Hospital. To establish the diagnosis of salivary gland tumour we use clinical history, cytologic examination, CT scanning and MRI. Incisional biopsy, which may cause injury to the facial nerve, was avoided and we used mostly fine needle aspiration (FNAB). Results: The results were compared with the post-operative histological diagnosis and the only criterion of treatment success was this correspondence. The cytologic investigation allowed to correct the diagnosis in 94% of the cases. The morphology of tumours was the following: pleomorphic adenoma (mixed tumour) 47; monomorphic adenoma 1; squamouscell carcinoma 10; adenocarcinoma 2; cylindroma 1. Conclusions: The result of FNAB gives accurate diagnosis in 94% cases of mixed tumours and Wartin tumour, which are the most common tumours of the salivary glands. P.258 Solitary submucous neurofibroma of the mandible R. Depprich, J. Handschel, U. Meyer, N. K¨ubler. Department of Cranio- and Maxillofacial Surgery, Heinrich-Heine-University Duesseldorf, Germany Introduction and Objectives: Neurofibroma is an uncommon tumour of the oral cavity but it represents the most common neurogenic tumour and is most often seen as part of the generalized syndrome of neurofibromatosis, whereas the solitary tumour is a rare variant. Case report: We report about a 64-year-old male patient presenting with an enormous exophytic tumour in the oral cavity covering almost all the lingual side of the left half of the mandible. Pre-operative panoramic radiographs showed little to

Abstracts, EACFMS XVIII Congress moderate interdental height loss of bone between the last lower molars on the left but no other abnormalities. Surgical treatment consisted of the resection of the soft tissue tumour, extraction of teeth 37 and 38 and a modelling osteotomy. Results: The histopathological examination revealed a submucous benign mesenchymale proliferation with no signs of malignancy. Immunohistochemical findings showed a solitary submucous neurofibroma with a predominate fibromatous component. Conclusion: Pathogenesis of solitary neurofibroma, diagnostic criteria and possibilities for treatment are discussed.

P.259 The role of sphingomyelin on RANKL-stimulated differentiation into osteoclasts Y. Ogawa1 , S. Goda2 , T. Ikeo2 , S. Morita1 . 1 First Department of Oral and Maxillofacial Surgery, 2 Department of Biochemistry, Osaka Dental University, Japan Sphingomyelin (SM) is a major component of lipid rafts, which are specialized structures that enhance the efficiency of membrane receptor signalling and are the main source of ceramide. Among lipid rafts made up of cholesterol, glycosphingolipids and sphingomyelin (SM)-rich membrane microdomains, receptor activator of NF-úB (RANK) is facilitated by the localization of receptors and proximal signaling components. Rafts are involved in receptor activator of NF-úB ligand (RANKL)/RANKinduced differentiation into osteoclasts through the translocation and clustering of RANK into rafts upon stimulation. Lysenin, an SM-directed cytolysin isolated from the earthworm binds to sphingomyelin-rich membrane domains and induces pore formation in the plasma membrane. We examined that the role of SM in RANKL-stimulated proliferation and differentiation into osteoclasts with RAW264 cells.Lysenin did not affect proliferation in RAW264 cells incubated with 100 ng/ml lysenin in 7.5% FBS for 24 h. In contrast, in RAW264 cells incubated with 50 ng/ml RANKL in the presence or absence of lysenin for 5 days in 7.5% FBS´a-MEM and analysed by tartrate-resistant acid phosphatase (TRAP) staining, RANKL-mediated differentiation was markedly inhibited by lysenin in a dose-dependent manner. RANKL-mediated phosphorylation of MAP kinase, p38 and MEK, was blocked by 100 ng/ml lysenin. These results suggest that RANKL/RANK can initiate lipid raft micro-domain-dependent signalling events that affect the differentiation and phosphorylation of MAP kinase.

P.260 Apoptosis of oral epithelial cells in oral lichen planus caused by upregulation of BMP-4 S.H. Song, B.Y. Yang, S.G. Kim, B.O. Cho. Department of Oral and Maxillofacial Surgery, Hallym Sacred Hospital, Anyang, South Korea Introduction: Bone morphogenic protein (BMP-4) is a member of transforming growth factor (TGF-b) family and is involved in various functions including apoptosis during neural ectoderm development. The objective of this study is to determine whether BMP-4 is involved in apoptosis, one characteristic, of human oral lichen planus (OLP). Methods: Immunohistochemistry and in situ hybridization for BMP-4 were carried out in OLP (n = 21) and normal human oral mucosa (NOM, n = 31). Five tissue samples from NOM and OLP underwent RT-PCR. In vitro organ culture of oral mucosa was carried out with beads soaked with various concentrations of BMP-4 (0.1, 1, and 10 mg/ml). The samples from in vitro organ culture underwent haematoxylin and eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick