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A FRONTAL CEPHALOMETRIC STUDY ON THE REFERENCE LINES TO ASSESS THE CRANIOMAXILLOFACIAL ASYMMETRY (안면 비대칭의 평가를 위한 기준에 관한 정모 두부 방사선 계측학적 연구)

  • Paek, Sun-Ho;Ahn, Byoung-Keun;Kim, Sun-Hae;Sohn, Hong Bum;Han, Ho Jin;Kang, Soo-Man
    • The korean journal of orthodontics
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    • v.23 no.1 s.40
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    • pp.1-15
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    • 1993
  • This study was undertaken to investigate the midline having the least difference between the right and left structures among the lines that had been used in the study of the craniomaxillofacial asymmetry. The sample of this study consisted of twenty six Korean girls(average 18.9 years old) having normal facial appearance and occlusion. On the frontal cephalometric films of the sample, we divided the whole craniomaxillofacial area into four portions, i.e., cranial, upper facial, lower facial, and dental portion. So, we have found the midlines having the least difference in the whole craniomaxillofacial area itself, and in the each divided four portions, furtherly in the other portions from aimed portion. The findings were as follow: 1. In the whole craniomaxillofacial area, the connecting line between crista galli and anterior nasal spine and the perpendicular bisecting line between right and left foramen rotundums were suitable for the midline. 2. In the cranial portion, established all six lines were suitable for midlines. In the other portions, the perpendicular bisection line between both condylion, the line passing the contact point between right and left mandibular central insisiors among the perpendicular lines between right and left mandibular central incisial tips were suitable midlines fer evaluating the asymmetry of cranial portion. 3. In the upper facial portion, the perpendicular bisecting line between right and left zygions was the most suitable midline. In the other portions, the line between the crista galli and the most superior point of the odontoid process, the perpendicular bisecting line between right and left gonions, the perpendicular bisecting line between right and left condylions, and perpendicular bisecting line between right and left foramens rotundum were suitable midlines for evaluating the asymmetry of the upper facial portion 4. In the dental portion, the perpendicular bisecting lines between right and left buccal cusps of both maxillary first molars and between right and left mandibular first molars were suitable midlines. In the other portions, the perpendicular bisecting line between right and left landmarks crossing the lesser wing of the sphenoid bone and orbit, the perpendicular bisecting line between right and left mental foramens, and the connecting line between crista galli and prosthion were suitable midlines for evaluating the asymmetry of dental portion. 5. In the lower facial portion, the perpendicular bisecting lines between right and left condylions and between right and left gonions were suitable midlines. In the other portions, the line between the crista galli and anterior nasal spine, the perpendicular bisecting line between right and left foramen rotundums, and the perpendicular bisecting lines between right and left buccal cusps of both mandibular first molars and between right and left maxillary first molars were suitable midlines for evaluating the asymmetry of the lower facial portion.

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CLINICAL STUDY OF POSITRON EMISSION TOMOGRAPHY WITH $[^{18}F]$-FLUORODEOXYGLUCOSE IN MAXILLOFACIAL TUMOR DIAGNOSIS (구강 악안면 영역의 암종 진단에 있어서 $[^{18}F]$-Fluorodeoxyglucose를 이용한 양전자방출 단층촬영의 임상적 연구)

  • Kim, Jae-Hwan;Kim, Kyung-Wook;Kim, Yong-Kack
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.5
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    • pp.462-469
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    • 2000
  • Positron Emission Tomography(PET) is a new diagnostic method that can create functional images of the distribution of positron emitting radionuclides, which when administered intravenously in the body, makes possible anatomical and functional analysis by quantity of biochemical and physiological process. After genetic and biochemical changes in initial stage, malignant tumor undergoes functional changes before undergoing anatomical changes. So, early diagnosis of malignant tumors by functional analysis with PET can be achieved, replacing traditional anatomical analysis, such as computed tomography(CT) and magnetic resonance image(MRI), etc. Similarly, PET can identify malignant tumor without confusion with scar and fibrosis in follow up check. In the Korea Cancer Center Hospital(KCCH) from October 1997 to September 1999, clinical study was performed in 79 cases that underwent 89 times PET evaluation with [18F]-Fluorodeoxyglucose for diagnosis of oral and maxillofacial tumors, and the data was analysed by Bayesian $2{\times}2$ Classification Table. The results were as follows : Evaluation for initial diagnosis with FDG-PET (P<0.005) 1. Agreement rate or accuracy rate is 88.9%. 2. Sensitivity is 95.2%, and specificity 66.7%. 3. Positive predictive rate is 90.9%, and negative predictive rate 80.0%. 4. In consideration of tumor stage, diagnostic rate in less than stage II was 90% and in greater than stage III 100%. 5. In consideration of tumor size, diagnostic rate in less than T2 was 92.3% and in greater than T3 100%. After primary treatment, evaluation for follow up check with FDG-PET (P < 0.001) 1. Agreement rate or accuracy rate is 85.4%. 2. Sensitivity is 87.5%, and specificity 82.4%. 3. Positive predictive rate is 87.5%, and negative predictive rate 82.4%. 4. In 24 recurred cases, 6 had distant metastasis, and 5 of them were diagnosed with FDG-PET, resulting in diagnostic rate of FDG-PET of 83.3%. From the above results, Positron Emission Tomography with [18F]- Fluorodeoxyglucose appears to be more sensitive and accurate for detecting the presence of oral and maxillofacial tumors, and has various clinical applications such as early diagnosis of tumor in initial and follow up check and detection of distant metastasis.

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CONDYLAR ADAPTATION UNDER LATERAL DEVIATION OF THE RABBIT MANDIBLE (가토의 하악골 측방 변위에 의한 하악과두 변화)

  • Park, Hae-Sung;Park, Young-Ju;Ahn, Byoung-Keun;Rhee, Gun-Joo;Park, Jun-Woo;Lee, Young-Chan;Cho, Byoung-Ouck
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.5
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    • pp.446-454
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    • 2000
  • Condylar process of mandible is an important and fuctionally versatile part of the mandible. There were quite large amount of investigations on the functional and anatomical adaptation of the temporomandibular joint(TMJ) to the surrounding tissues. But controversies on the mechanism of functional adaptation of the joint still exist. In this research, we investigated changes in the TMJ by the lateral deviation of the maxillary incisor to shift the mandible right, and bone the undecalcified microscopic sections with fluorescent microscope and von Kossa staining with bright field microscope. Results were as follows: 1. Lateral deviation rendered shifting and tilting of the mandible, There were, compressions in the right joint and opening of the left joint space at early stage. At the same time, both condyles shifted slightly to anterior. 2. After $2{\sim}4$ weeks, left condyle showed anterior displacement and compressions in the joint space. Right condyle showed only slight shift to the anterior. 3. Regardless of the direction of the lateral shift, anterior bite plate compressed both condyle heads until 2 weeks. 4. There are bone resorptions in the anterior aspect of the condyle head and apposition of posterior border. Bone remodeling were observed between 3 and 4 weeks. 5. After 8 weeks of the experiment, there were little differences in condylar morphology between experimental and control group, though slight shifting and compression were still present in the experimental group. Lateral deviation of mandible evoked active remodeling of the TMJ until functional and anatomical reconstruction of TMJ position was achieved.

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FUNCTIONAL RECONSTRUCTION OF DENTO-PALATAL AND MAXILLARY DEFECT USING STAGED OPERATION OF PREFABRICATED SCAPULAR FREE FLAP AND DENTAL IMPLANTS (분층피부와 분말골로 이식 전 처리된 유리견갑골근피판과 임플란트 보철을 이용한 경구개와 상악골의 기능적 재건)

  • Lee, Jong-Ho;Kim, Myung-Jin;Park, Jong-Chul;Kim, Yung-Soo;Ahn, Kang-Min;Paeng, Jun-Young;Kim, Sung-Min;Myoung, Hoon;Hwang, Soon-Jung;Seo, Byoung-Moo;Choi, Jin-Young;Choung, Pill-Hoon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.30 no.4
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    • pp.301-307
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    • 2004
  • The flap considered at first for the reconstruction of large maxillary defect, especially mid-face defect, is scapular free flap, because it provides ample composite tissue which can be designed 3-dimensionally for orbital, facial and oral reconstruction. In case of maxillary defect involving hard palate, however, this flap has some limitations. First, its bulk prevents oral function and physio-anatomic reconstruction of nasal and oral cavity. Second, mobility and thickness of cutaneous paddle covering the alveolar area reduce retention of tissue-supported denture and give rise to peri-implantitis when implant is installed. Third, lateral border of scapula that is to reconstruct maxillary arch and hold implants is straight, not U-shaped maxillary arch form. To overcome these problems, new concept of step prefabrication technique was provided to a 27-year-old male patient who had been suffering from a complete hard palate and maxillary alveolar ridge defect. In the first stage, scapular osteomuscular flap was elevated, tailored to fit the maxillary defect, particulated autologous bone was placed subperiosteally to simulate U-shaped alveolar process, and then wrapped up with split thickness skin graft(STSG, 0.3mm thickness). Two months later, thus prefabricated new flap was elevated and microtransferred to the palato-maxillary defect. After 6 months, 10 implant fixtures were installed along the reconstructed maxillary alveolus, with following final prosthetic rehabilitation. The procedure was very successful and patient is enjoying normal rigid diet and speech.

EFFECT OF PLATELET-RICH PLASMA ON BONE FORMATION IN DISTRACTED AREA OF CANINE MANDIBLE (성견하악골의 신연 부위에서 골형성에 대한 혈소판-풍부 혈장의 효과)

  • Ryu, Soo-Jang;Yi, Choong-Kook;Choi, Byung-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.6
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    • pp.498-510
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    • 2001
  • Distraction osteogenesis refers to the biological process responsible for new bone formation between bone segments by gradual distraction after osteotomy. For the past several years, various inconveniences including a protracted consolidation period that requires patients to wear a distractor frame longer, as well as higher medical costs, have not been remedied by improvements in osteotomy, distraction rate and monitoring system. Furthermore, side effects such as pin tract infections and soft tissue swelling may arise due to the long treatment period. These drawbacks form the rationale of this study which purports to seek a method by which the consolidation period can be reduced. This paper examines how platelet-rich plasma(PRP), known to facilitate osteogenesis, influences bone formation when applied in distracted area. Ten mongrel dogs, which were made to wear external distractor frames after osteotomy in both sides of the mandible, were used as subjects. After a 7day period of latency, distraction was carried out at a rate of 1mm/day for 14 consecutive days. After the onset of distraction, 2ml of PRP and a mixture of calcium gluconate and thrombine were injected into the center of the distracted callus on the left side of the mandible. The left was injected with PRP while the right side was set as the control site without PRP treatment. Execution at the onset of distraction and in 2 weeks, 4 weeks and 8 weeks after the consolidation period, clinical and radiographic tests, bone mineral density examination, histological examination and histomorphometric analysis were conducted to compare both sides. The results are summarized as follows: 1. Based on the clinical examination at two weeks, more remarkable cortical bone formation was found on the buccal and lingual side of the distracted area in the PRP treatment site than in the control site. No visual difference was found between the PRP treatment site and the control site at four eight weeks. 2. Based on the radiological examination, a distinct increase in the radiopaque appearance of the PRP treatment site was revealed at two weeks, but this increase appeared to slow down at four and eight weeks. 3. Examination of bone mineral density revealed a significant difference at two weeks with the PRP treatment site yielding density two times higher than the control site. This difference lessened after four weeks, and disappeared at eight weeks. 4. The histomorphometric examination revealed that about 20% more bony trabeculae area(20%, higher) was formed in the PRP treatment site than in the control site. In conclusion, it can be said that PRPs effect on stimulating bone formation in the PRP treatment site manifest as early as two weeks. Trabeculae formation likewise increased throughout the whole period. If this result can be applied to humans, the consolidation period can be reduced by injecting PRP into the distracted area.

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Effects of EGFR, CK19, CK20 and Survinin Gene Expression on Radiotherapy Results in Patients with Locally Advanced Head and Neck Cancer

  • Kekilli, Kezban Esra;Abakay, Candan Demioz;Tezcan, Gulcin;Tunca, Berrin;Egeli, Unal;Saraydaroglu, Ozlem;Esbah, Onur;Ekinci, Ahmet Siyar;Arslan, Sonay;Uslu, Nuri;Ozkan, Lutfi
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.7
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    • pp.3023-3027
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    • 2015
  • Purpose: To investigate the effects of epidermal growth factor receptor (EGFR), cytokeratin 19 (CK19), cytokeratin 20 (CK20) and survinin gene expression on local control (LC) and overall survival (OS) in patients with locally advanced head and neck cancer (LAHNC) who were administered radiotherapy (RT). Materials and Methods: Twenty-six patients who were admitted to Uludag University Medical Faculty Department of Radiation Oncology with a diagnosis of LAHNC (GIII-GIV) were included in this study. Gene expression was evaluated in tumor tissues and peripheral blood. RNA isolation was performed on paraffinized tumor tissues and peripheral blood samples obtained before RT (BR). The densities of the obtained RNAs were analyzed at 260/280 nm. cDNA samples obtained from total RNA,EGFR, CK19, CK20 and survinin gene expression levels were assessed via the Sybr Green method and data were analyzed with the ${\Delta}{\Delta}Ct$ method. The same process was repeated for peripheral blood samples taken after RT (AR). Results: The female/male ratio was 3:23 and the mean age was 56.5 years (38-75years). After radiotherapy, CK19 and CK20 levels in the peripheral blood were found to be correlated according to Pearson correlation analysis(p=0.049). This result indicates a possibility of remaining positive for CK19 and CK20 in the peripheral blood even after RT in patients with CK19, CK20, and EGFR positive tumors before RT. There was a statistically significant correlation between survinin levels measured BR and AR (p=0.028). Conclusions: In this study, we found that patients with any EGFR, CK19, CK20 or survinin positivity in their peripheral blood obtain less benefit from radiotherapy. A wider patient population and advanced protein analyses are necessary in order to increase the reliability of our findings.

Assessment of Cervical Cancer Risk in Women between 15 and 49 Years of Age: Case of Izmir

  • Sogukpınar, Neriman;Saydam, Birsen Karaca;Can, Hafize Ozturk;Hadımli, Aytul;Bozkurt, Ozlem Demirel;Yucel, Ummahan;Kocak, Yeliz Cakir;Akmese, Zehra Baykal;Demir, Dogan;Ceber, Esin;Ozenturk, Gulsun
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.3
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    • pp.2119-2125
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    • 2013
  • Background: The aim of the study was to determine risk factors for cervical cancer for women in Izmir. Methods: This cross-sectional, descriptive field covered a population of 4319 women of reproductive age (15-49) (household registration in the Mukhtar's office-2007). A total of 1,637 women were included in the sample given a four-part questionnaire through face-to-face interview by visiting the women in their homes in order to determine socio-demographic factors, obstetric history, genital hygiene and the use of family planning methods. In addition, during the data collection process, the women were given group training in order to raise awareness of cervical cancer. The number and percentage distributions of the data were calculated. Results: While the average age of the women was $31.9{\pm}9.77$ (Min: 15.00-Max: 49.00), education level of 43.4% of them was elementary school only. It was determined that 70.3% of the women experienced at least one pregnancy, 71.0% had vaginal delivery and 75.9% used a contraceptive method. In the study it was determined that among the cervical cancer related risks vaginal delivery, vaginal lavage and having three or more pregnancies had the highest rates, while having sexual intercourse before 16 years of age and having more than one sexual partner constituted lower rates. The rate of the women who stated not having a smear in the last three years was 82.4%. Conclusions: Considering the case in terms of having Pap smear test, women's awareness on the risk factors and early diagnosis of cervical cancer was found to be low. Due to this reason, awareness of women has to be raised through education.

Korean Phoneme Recognition Using Self-Organizing Feature Map (SOFM 신경회로망을 이용한 한국어 음소 인식)

  • Jeon, Yong-Koo;Yang, Jin-Woo;Kim, Soon-Hyob
    • The Journal of the Acoustical Society of Korea
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    • v.14 no.2
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    • pp.101-112
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    • 1995
  • In order to construct a feature map-based phoneme classification system for speech recognition, two procedures are usually required. One is clustering and the other is labeling. In this paper, we present a phoneme classification system based on the Kohonen's Self-Organizing Feature Map (SOFM) for clusterer and labeler. It is known that the SOFM performs self-organizing process by which optimal local topographical mapping of the signal space and yields a reasonably high accuracy in recognition tasks. Consequently, SOFM can effectively be applied to the recognition of phonemes. Besides to improve the performance of the phoneme classification system, we propose the learning algorithm combined with the classical K-mans clustering algorithm in fine-tuning stage. In order to evaluate the performance of the proposed phoneme classification algorithm, we first use totaly 43 phonemes which construct six intra-class feature maps for six different phoneme classes. From the speaker-dependent phoneme classification tests using these six feature maps, we obtain recognition rate of $87.2\%$ and confirm that the proposed algorithm is an efficient method for improvement of recognition performance and convergence speed.

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Techniques of XML Query Caching on the Web (웹에서의 XML 질의 캐쉬 기법)

  • Park, Dae-Sung;Kang, Hyun-Chul
    • The Journal of Society for e-Business Studies
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    • v.11 no.1
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    • pp.1-23
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    • 2006
  • As data on the Web is more and more in XML due to proliferation of Web applications such as e-Commerce, it is strongly required to rapidly process XML queries. One of such techniques is XML query caching. For frequently submitted queries, their results could be cached in order to guarantee fast response for the same queries. In this paper, we propose techniques for XML query performance improvement whereby the set of node identifiers(NIS) for an XML query is cached. NIS is most commonly employed as a format of XML query result,, consisting of the identifiers of the XML elements that comprise the query result. With NIS, it is suitable to meet the Web applications data retrieval requirements because reconstruction and/or modification of query results and integration of multiple query results can be efficiently done. Incremental refresh of NIS against its source updates can also be efficiently done. When the query result is requested in XML, however, materialization of NIS is needed by retrieving the source XML elements through their identifiers. In this paper, we consider three different types of NISs. proposing the algorithms of their creation, materialization, and incremental refresh. All of them were implemented using an RDBMS. Through a detailed set of performance experiments, we showed the efficiency of the proposed XML query caching techniques.

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The Determinants of User Resistance to Adopting e-Books : Based on Innovation Characteristics and User Attitude (전자책 수용에 대한 사용자 저항 결정요인 : 혁신특성과 사용자태도를 중심으로)

  • Lee, Aeri;Choi, Jaewon;Kim, Kyung Kyu
    • The Journal of Society for e-Business Studies
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    • v.17 no.4
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    • pp.95-115
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    • 2012
  • The e-Book market has rapidly grown as an innovative product which is mixed its traditional and technological characteristics. However, decreasing user resistance to the e-Book is very important to continually keeping up its market growth. Previous studies for user resistance have been studied as a negative barrier for various innovative products with importance of user resistance. Nevertheless, the factors for user' resistance to the e-Book field have not been found out considering both perceived value and switching cost. Especially, both innovative technology and user specifics should be considered when explaining user resistance to adopting e-Books. Thus, the purpose of this study is to understand the process for user resistance to the e-book and find out its antecedents with perceived value and switching cost at the same time. As a result, it appeared that triability, uncertainty and complexity affected perceived value and switching cost. The user-based antecedents like social norm and perceived value increased the effect of self-efficacy. Also, self-efficacy and perceived value decreased user resistance whereas switching cost increase user resistance to the e-Book perspective.