• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2009년도 춘계학술발표대회
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• pp.253-256
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• 2009

이 논문에서는 접근성 있는 리치 인터넷 애플리케이션을 구현하였을 때 우리나라에서 입수 가능한 화면 낭독 프로그램이 이들 리치 인터넷 애플리케이션의 접근성 기능을 충분히 지원하는가를 실험을 통하여 파악하였다. 실험 결과, 미국 Freedom Scientific사의 JAWS for Windows 10.0 한글판이 실험에 사용한 모든 애플리케이션의 접근성 기능을 지원하였다. 그러나 국산 화면 낭독 프로그램은 개발 환경에 따라 접근성 지원 기능이 떨어지고 있음을 확인할 수 있었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제46권6호
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• pp.443-444
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• 2020

• 치과방사선
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• 제21권2호
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• pp.287-296
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• 1991

The purpose of this experiments is to compare the vertical and horizontal magnification, and the distortion of the radiographic image according to the types of panoramic machines. Total 70 radiographs, 10 radiographs out of 7 panoramic machines respectively, were taken from the dry skull with metal balls in the periapical areas of the central incisor, the canine, the second premolar, and the second molar in the maxilla and the mandible. And the author evaluated the vertical and horizontal magnification degrees, and the distortion degrees of radiographic images obtained from each panoramic machine. The results were as follows: There were no significant differences in the vertical and horizontal magnification degrees on the various portions of the jaws (p> 0.05). But there were higher magnification degrees in the Panoura 10C, Panograph Ⅱ, and Veraview than those in other panoramic machines. The lowest average magnification degree was 20.27% vertically, 20.94% horizontally using the Panoradix. The highest average magnification degree was 27.64% vertically, 28.48% horizontally using the Panograph Ⅱ. The lowest distortion was shown using the Panoura 10C in the maxilla, but there was not statistically significant difference between the panoramic machines in the mandible (p>0.05). There were no differences in the vertical and horizontal magnification degrees according to the types of the rotation centers.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제43권5호
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• pp.312-317
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• 2017

Objectives: In order to assess clinical behavior, response to treatment, and factors influencing prognosis of Korean patients with osteosarcoma of the jaws (OSJ). Materials and Methods: A retrospective study of clinical, and pathological records of 26 patients with OSJ treated at the Department of Oral and Maxillofacial Surgery in Yonsei University Dental Hospital from 1990 to March 2017. Results: Of 26 patients, there were 9 men (34.6%) and 17 women (65.4%). Twenty-one of 26 patients had osteosarcoma of the mandible, and 5 of 26 patients had osteosarcoma of the maxilla. The histopathology of OSJ is highly variable, ranging from chondroblastic type (6 out of 26), osteoblastic type (10 out of 26), fibroblastic type (2 out of 26), to the rare variants like mixed type, small cell osteosarcoma types and more. All patients underwent gross total excision and only a few patients underwent neoadjuvant chemotherapy. Postoperative chemotherapy was given to most of the patients as adjuvant treatment or in combination with radiotherapy. The overall survival rate was 73.1% with an overall 2-year survival rate of 83.3%. The overall 5-,10-,15-year survival rates in this study were 73.5%, 73.5%, 49%, respectively. Using Kaplan-Meier analysis with log rank tests, the size of tumor (T-stage), and resection margins were found to affect the survival rate significantly. The chemotherapy was not significantly associated with improved survival rate. Conclusion: Surgical resection with a clear margin is the most important factor in disease survival. The role of chemotherapy and radiotherapy in OSJ remains controversial, and deserves further studies.

• 대한치과교정학회지
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• 제35권3호
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• pp.238-249
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• 2005

악골부조화가 심할수록 기능향상을 위해 악골 및 치아 치조부에서의 보상반응이 현저해진다. 대표적인 현상으로 하악과두의 변위와 상악교합평면의 변화 등을 들 수 있다. 이러한 상하악골에서의 적응성 변화는 안모의 심미성과 교합의 기능 향상을 위해, 술후 안정성을 높이기 위해서 악교정수술을 통해 반드시 수정해야 할 요소이다 적절한 상악골 수술을 위해서 통상적으로 model surgery를 시행하여 왔으나 이의 단점을 보완하기 위해 Surgical Jaw Relator를 고안하였으며 이는 교합기의 mounting plate 대신에 부착함으로써 상하악 모형의 삼차원적 이동과 회전이 가능하도록 설계되어 있으며 기존의 모든 종류(Panadent. Sam, Denar, Hanau 등)의 교합기에 손쉽게 부착하여 수술용 스프린트의 제작 시간을 대폭 줄일 수 있는 장점이 있다 상악골 상방 이동이 필요한 하악전돌 증례와 상악골 하방 이동이 요구되는 하악후퇴 증례 등에 본 기구를 적용한 결과 양호한 수술 결과를 얻었으며, 이로써 정교한 상악 수술을 요하거나 명확한 수술 계획이 설정된 증례 등에서 본 기구를 적절하게 사용할 경우 수술용 스프린트를 효율적으로 제작하는데 다소 도움이 될 것으로 생각된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권5호
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• pp.417-421
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• 2005

This study was to analyze the changes of levels of alkaline phosphatase before and after enucleation of jaw cysts combined with bone grafting, and to evaluate biochemically the effectiveness of the early detection of bone healing and infection as a prognostic marker. Eighteen patients (13 males, 5 females) with cystic lesions of the jaws were divided into two groups. The bone graft group underwent enucleation and bone graft. The control group underwent only enucleation. Both groups were measured levels of ALP before surgery, and plus-minus 4 weeks postoperatively. The more discriminating results were obtained in the bone graft group. The results were as follows : 1. Levels of ALP after enucleation of jaw cysts were decreased in all patients with and without bone graft. 2. The bone graft group showed more marked decrease in variation of levels of ALP than the control group.(p=0.008) This should be considered as a result of increased osteoblastic activity and new bone formation. 3. Such variation could be used as a prognostic marker for bone healing after cyst operation. In the cost/benefit ratio, measurement of ALP activity could be useful as a convenient procedure in routine clinical practice.

• Imaging Science in Dentistry
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• 제42권1호
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• pp.5-12
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• 2012

Purpose : This study was performed to evaluate possible variations in maxillary and mandibular bone texture of normal population using the fractal analysis, particles count, and area fraction in intraoral radiographs. Materials and Methods : Periapical radiographs of patients who had full mouth intraoral radiographs were collected. Regions of interest ($100{\times}100$ pixels) were located between the teeth of the maxillary anterior, premolar, and molar area, as well as the mandibular anterior, premolar, and molar areas. The fractal dimension (FD) was calculated by using the box counting method. The particle count (PC) and area fraction (AF) analyses were also performed. Results : There was no significant difference in the FD values among the different groups of age, gender, upper, and lower jaws. The mean FD value was $1.49{\pm}0.01$. The mean PC ranged from 44 to 54, and the mean AF ranged from 10.92 to 11.85. The values of FD, PC, and AF were significantly correlated with each other except for the upper molar area. Conclusion : According to the results, patients with normal trabecular pattern showed a FD of approximately 1.5. Based on these results, further investigation would be recommended if the FD value of patient significantly differenct from this number, since the alteration of this value indicates microstructural modification of trabecular pattern of the jaws. Additionally, with periapical radiographs, simple and cost-effective, PC and AF could be used to assess the deviation from the normal.

• 치과방사선
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• 제18권1호
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• pp.153-163
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• 1988

The purpose of this study is to investigate on the clinical and radiographic patterns of cystogenic ameloblastoma of the jaws. The author studied 64 cases of cystogenic ameloblastoma with regard to age, sex distribution, the site of the lesion and several radiographic features. The results were as follows: 1. The average age was found to be 23.0 years, with a range of 4 to 56 years. The incidence was highest in the second and third decades (72%) and total 64 cases consists of 36 males and 28 females. 2. Fifty-nine cases were found in mandible and 5 cases in maxilla. 3. The specific site distribution was found to be 57.8% ramus, coronoid process and condyle, 34.4% premolar-molar region, and 7.8% were located in mandibular symphysis bilaterally. 4. From the total 64 cases, 28 (44%) were associated with an impacted tooth, especially mandibular second and third molar, 36(52%) failed to show any association with tooth impaction. It was found that the average age for impaction-associated tumors was 19.8 years whereas lesions without impaction occurred at an average age of 25.6 years, which was statistically significant. 5. Fifty-three(82%) cases showed unilocular radiolucencies, eleven (17%) cases showed multilocular radiolucencies. It was found that the average age for unilocular lesions was 22.3 years whereas lesions showing multilocularity occurred at an average age of 26.4 years, which was not statistically significant. 6. Of the 21 patients who had been followed for more than 2 years, only 4 patients treated by enucleation or curettage recurred (19% recurrence).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권6호
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• pp.515-519
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• 2011

Cemento-osseous dysplasia occurs in the tooth bearing areas of the jaws and is probably the most common fibro-osseous manifestation. They are usually classified into three main groups according to their extent and radiographic appearance: periapical (surrounds the periapical region of teeth and are bilateral), focal (single lesion) and florid (scleroticsymmetrical masses) cemental-osseous dysplasias. Florid cemento-osseous dysplasia clearly appears to be a form of bone and cemental dysplasia that is limited to the jaws. Patients do not have laboratory or radiologic evidence of bone disease in other parts of the skeleton. For asymptomatic patients, the best management consists of regular recall examinations with prophylaxis and the reinforcement of good home hygiene care to control periodontal disease and prevent tooth loss. The treatment of symptomatic patients is more difficult. At this stage, there is an inflammatory component caused by the disease and the process is basically a chronic osteomyelitis involving dysplastic bone and cementum. Antibiotics might be suggested, but are not always effective. Two cases of florid cemento-osseous dysplasia diagnosed in two Korean females are reported with a review of the relevant literature.

• Journal of Yeungnam Medical Science
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• 제25권2호
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• pp.108-116
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• 2008

Background : When surgeons plan mandible ortho surgery for patients with skeletal class III facial asymmetry, they must be consider the exact method of surgery for correction of the facial asymmetry. Three-dimensional (3D) CT imaging is efficient in depicting specific structures in the craniofacial area. It reproduces actual measurements by minimizing errors from patient movement and allows for image magnification. Due to the rapid development of digital image technology and the expansion of treatment range, rapid progress has been made in the study of three-dimensional facial skeleton analysis. The purpose of this study was to conduct 3D CT image comparisons of mandible changes after mandibular surgery in facial asymmetry patients. Materials & methods : This study included 7 patients who underwent 3D CT before and after correction of facial asymmetry in the oral and maxillofacial surgery department of Yeungnam University Hospital between August 2002 and November 2005. Patients included 2 males and 5 females, with ages ranging from 16 years to 30 years (average 21.4 years). Frontal CT images were obtained before and after surgery, and changes in mandible angle and length were measured. Results : When we compared the measurements obtained before and after mandibular surgery in facial asymmetry patients, correction of facial asymmetry was identified on the "after" images. The mean difference between the right and left mandibular angles before mandibular surgery was $7^{\circ}$, whereas after mandibular surgery it was $1.5^{\circ}$. The right and left mandibular length ratios subtracted from 1 was 0.114 before mandibular surgery, while it was 0.036 after mandibular surgery. The differences were analyzed using the nonparametric test and the Wilcoxon signed ranks test (p<0.05). Conclusion: The system that has been developed produces an accurate three-dimensional representation of the skull, upon which individualized surgery of the skull and jaws is easily performed. The system also permits accurate measurement and monitoring of postsurgical changes to the face and jaws through reproducible and noninvasive means.