1148 Abstracts 149 The correlation between mallampati classification and technical difficulties of inferior alveolar nerve blockage S.S. Soydan ∗ , S. Gulsever, B. Bayram, S. Uckan Oral and Maxillofacial Surgery, Baskent University, Faculty of Dentistry, Ankara, Turkey Objectives: Mallampati classification is a standard preoperative airway exam- ination assessing mouth opening and structures within the oral cavity. Hypoth- esis of this study was there is a positive correlation between mallampati score and clinician’s viewing and injection difficul- ties during the inferior alveolar nerve (IAN) blockage. Materials and methods: 150 (86 female/64 male) patients were included in this prospective, double blind study. Patients who had restricted mouth opening from any reason were excluded from the study. Mallampati airway class, age, sex, body mass index (BMI), obstructive sleep apnea (OSA) and/or snoring history were documented by same chief resident for all patients at the beginning of the appoint- ment. Injection and viewing difficulties during the IAN anesthesia deposition and surgical procedure, latent duration for local anesthesia and total deposited anesthetic solution amount were recorded by same first year resident. Visual Analogue Scale (VAS) was used for evaluation of viewing and injection difficulties during the IAN blockage and surgical procedure. Results were statistically evaluated by regression analysis. Results: There was a statistically significant relationship between BMI, OSA, snoring and high mallampati score (p < 0.05). Majority of the snoring prob- lem was observed in male patients however sleep apnea problem was approximately equal for male and female patients. There was also a statistically significant relation- ship between the VAS score of viewing and injection difficulty during the IAN block- age and high mallampati score (p < 0.05). Conclusions: A clinician should be aware of possible relationship between a high mallampati score and difficulty in viewing the injection location of an IAN blockage. Conflict of interest: None declared. doi:10.1016/j.ijom.2011.07.412 150 Exodontia related complications at a Japanese hospital with a major HIV/AIDS treatment center Y. Nakagawa 1,∗ , F. Kanaya 1 , A. Tsuno 2 , Y. Maruoka 2 , Y. Kikuchi 1 , S. Oka 1 1 AIDS Clinical Center, Japan 2 Department of Dentistry and Oral Surgery, National Center for Global Health and Medicine, Tokyo, Japan Objective and methods: In order to investigate exodontia related complica- tions with HIV-1 immunodeficiency, a ret- rospective observational analysis reviewed patients’ chart for age, co-morbidity and blood test results before and after the den- tal extraction procedure. At Japan’s one of the largest HIV treatment hospital from January 2008 to August 2010, 120 HIV-1 infected patients received extractions. Results: Among 276 extraction proce- dures performed to these patients, there were 14 occasions (5.2%) of complica- tions that could be an obstacle during patients’ healing process such as alveolar osteitis. A case of post-extraction infec- tions was 0.4%. Comparing CD4 count at the time of exodonxia, complications occurred 6.1% of the time when the CD4 was under 200. When CD4 count was above 200, complications, including the only post-extraction infections case, occurred 5.2% of the time. HBV infec- tion, diabetes mellitus, HCV infection and hemophilia were common in this order among internal co-morbidities. For HIV- HBV cross-infected patients, complication was observed 19.4% of the extractions. For age groups, 6 complications occurred to patients in their 20s, 7 complications to the 30s and 7 to other age groups. Conclusion: Contrary from the percep- tion by some dental care providers, this study did not find an association between exodontia associated complications among HIV-1 infected patients and their age, CD4 or AIDS status. These results indicates that when the patient had good control of hygiene and comorbidities combined with appropriate antibiotics administration as post-procedure prophylaxis, there were no elevated risks of post-extraction complica- tions, even compared with HIV negative population. Conflict of interest: None declared. doi:10.1016/j.ijom.2011.07.413 151 Study of the relations between progressive/idiopathic condylar resorption and impaired bone/cartilage metabolism caused by chemokine receptor disorder Y. Maruoka 1,2,3,∗ , F. Kanaya 3 , A. Hoshino 3 , T. Iimura 4 , H. Imai 2,3,5 , R. Otsuka 3,6,7 , S. Ueha 8 , K. Fujioka 9 , Y. Katsuragawa 10 , T. Shimbo 3 , A. Mimori 11 , T. Yamazaki 12 , Y. Manome 9 , K. Omura 2 , K. Moriyama 7 , K. Matsushima 8 K. Yamamoto 3 , Research Group for the Establishment of Diagnostic Criteria and Standardized Effective Treatment Guidelines for Progressive Condylar Resorption 1 Dentistry/Oral and Maxillofacial Surgery, National Center for Global Health and Medicine, Japan 2 Oral and Maxillofacial Surgery, Tokyo Medical and Dental University, Japan 3 Research Institute, National Center for Global Health and Medicine, Japan 4 Oral Pathology, Tokyo Medical and Dental University, Tokyo, Japan 5 Dentistry/Oral and Maxillofacial Surgery, Hitachi, Ltd., Hitachinaka General Hospital, Ibaraki, Japan 6 Familiar Orthodontic Clinic, Saitama, Japan 7 Maxillofacial Orthognathics, Tokyo Medical and Dental University, Japan 8 Molecular Preventive Medicine, University of Tokyo, Japan 9 Molecular Cell Biology, Jikei University, Japan 10 Orthopedics, National Center for Global Health and Medicine, Japan 11 Rheumatology, Medical Center for Global Health and Medicine, Japan 12 Center for Preventive Medicine, University of Tokyo, Tokyo, Japan Object: Progressive condylar resorp- tion (PCR) is defined as diminishing condylar head volume with changes in condylar shape, often associated with decreased mandibular ramus height, mandibular retrusion and counter clock- wise rotation, resulting in progressive Class II basal bone in relation with anterior open bite. Patients are known to have relatively small and retruded mandible. Because of it, PCR patients often undergo inappropriate surgeries or unnecessary orthodontic procedures under misdiagnosis with maxillary protrusion and/or mandibular retrusion. Another proposed cause of condylar resorption is post orthognathic surgery complication, following excessive trau- matic external burden to the temporo- mandibular joint, TMJ. For clinical diag- nosis, many confused concepts were mixed