• Progress in Medical Physics
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• v.15 no.4
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• pp.237-246
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• 2004

Even though the wedge factor was defined by ICRU, RTPS uses other definition different from the wedge factor to consider the wedge effect to correct dose. Because the factors with different concept are defined in a very different way, replacement of different factor could make severe error of dose and is unacceptable because their values are very different from each other. Radiotherapy machine installed in department includes physical wedges and function of dynamic wedge by upper jaws, and Eclipse and Pinnacle$^{3}$ such as RTPS are used. The wedge factors, relative wedge output factors and wedge field output factors of physical wedges and dynamic wedges were measured by an ionization chamber in water phantom. They are analyzed and compared in according to wedge position, field size, wedge angle, X-ray quality, measurement condition. Wedge factor, relative wedge output factors and wedge field output factors of dynamic wedges comparing physical wedges have an effect of several factors. Main factors effecting to the factors of dynamic wedges were field size and wedge angle. Beam quality of X-ray introduces a few effect to the factors. Because the factors related to wedge and defined with different concepts are different from each other, to reduce dose error it should be input by values proper to RTPS.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.40 no.1
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• pp.59-73
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• 2003

As a means of overcoming the linguistic barrier between different languages in the Internet, a new sign-language communication system with CG animation techniques has been developed and proposed. In the system, the joint angles of the arms and the hands corresponding to the gesture as a non-verbal communication tool have been considered. The emotional expression, however, could as play also an important role in communicating each other. Especially, a comic expression is more efficient than real facial expression, and the movements of the cheeks and the jaws are more important AU's than those of the eyebrow, eye, mouth etc. Therefore, in this paper, we designed a 3D emotion editor using 2D model, and we extract AU's (called as PAU, here) which play a principal function in expressing emotions. We also proposed a method of generating the universal emotional expression with Avatar models which have different vertex structures. Here, we employed a method of dynamically adjusting the AU movements according to emotional intensities. The proposed system is implemented with Visual C＋＋ and Open Inventor on windows platforms. Experimental results show a possibility that the system could be used as a non-verbal communication means to overcome the linguistic barrier.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.5
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• pp.372-382
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• 2002

As the most of dentofacial deformity patients indicated to orthognathic surgery have strong desire for esthetic improvement as well as functional improvement, ideal esthetic evaluation should be made at surgical prediction. Lateral cephalographs has been commonly used for surgical prediction, however, remarkable discrepancy between esthetic viewpoint by simple looking and analysis on lateral cephalographs often found on evaluation of sagittal position of the upper and lower jaws especially in cases of mandibular prognathism of Koreans. In these cases, we have been employed Esthetic NaP(ENaP)-line for corrective evaluation and ideal surgical prediction on lateral cephalographs, but the efficacy of ENaP-line has not been evaluated. This is a study on efficacy of ENaP-line for orthognathic surgery of Korean mandibular prognathism. 170 Korean patients who had been diagnosed as mandibular prognathism and planned for orthognathic surgery at Department of Oral and Maxillofacial Surgery, College of Dentistry, Yonsei University during last 10 years are studied. The obtained results are as followings; among 170 patients of mandibular prognathism, 132 patients(77.6%) had not discrepancy in evaluation of sagittal position of the maxilla between cephalometric and esthetic evaluation(they are classified as Group I), however, 38 patients(22.4%) had definite discrepancy(they are classified as Group II). ENaP-line was employed in all cephalometric analysis of Group II. The proportions of male and female were similar in both Groups. Sixteen vertical reference lines perpendicular to 16 horizontal reference lines were obtained as followings; Each of the representative degree of ${\angle}SN/AFH$, ${\angle}SN/CFH$ and ${\angle}AFH/CFH$ obtained at Group I was applied to SN plane, AFH plane and CFH plane of Group II each other, and so 16 horizontal reference lines could be obtained individually according to each of the applied degree to each plane. And then their reliability to coincide with ENaP-line of Group II was evaluated. A vertical reference line perpendicular to a horizontal line made by application of the representative degree of ${\angle}$AFH/CFH in Group I to AFH line in Group II had the most highest coincidence with ENaP-line of Group II, however, its agreement was 42% in male and 47% in female. From this results, the rest of them should be determined their corrective jaw position definitely depend on

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.28 no.1
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• pp.27-36
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• 1998

The purpose of this study was to obtain information on the clinical and radiographic features of the fibro-osseous lesions in the jaws. For this study, the author examined and analysed the clinical records and radiographs of 71 cases of 68 patients in fibrous dysplasia, 35 cases of ossifying fibroma and 30 cases of 16 patients of periapical cemental dysplasia diagnosed by clinical and radiographic or histopathological examinations. The obtained results were as followings: L Fibrous dysplasia occurred most frequently in the 2nd decade (30.0％), ossifying fibroma in the 3rd-4th decades, periapical cemental dysplasia in the 4th decade, and all of three lesions showed slight predilection in females. In most cases, chief complaints were painless facial swelling in fibrous dysplasia and ossifying fibroma, and periapical cemental dysplasia was found accidentally in radiographs. 2. Fibrous dysplasia was occurred more frequently in maxilla, ossifying fibroma in mandible and both lesions in premolar-molar area. Periapical cemental dysplasia was occurred most frequently in the mandibular anterior area. The size of fibrous dysplasia was larger than that of ossifying fibroma, and the shape of ossifying fibroma was more round and elliptical than fibrous dysplasia whose was fusiform. 3. Fibrous dysplasia was shown homogeneous radiopaque shadow of 57.6％ and ossifying fibroma & periapical cemental dysplasia were shown mixed appearance of radiolucency and radiopacity shadows at 74.2％, 60.0％, respectively. 4. Fibrous dysplasia was entirely shown poorly defined at 87.7％, but ossifying fibroma & periapical cemental dysplasia were shown well outlined at 60.0％, 70.0％, respectively. 5. Cortical thinning and expansion were observed in fibrous dysplasia and ossifying fibroma, and severe in ossifying fibroma than fibrous dysplasia, and those signs were not seen in periapical cemental dysplasia. Loss of lamina dura was dominant in fibrous dysplasia and root resorption was dominant in ossifying fibroma. Displacement of mandibular canal and the degree of the increase of vertical dimension were alike in both lesions. Displacement of maxillary sinus or nasal cavity, thinning & expansion of the maxillary sinus were dominant in fibrous dysplasia. 6. Polyostotic fibrous dysplasia was occurred at 5.9％, Multiple periapical cemental dysplasia at 43.7％. Occurrence rate in the edentulous area of fibrous dysplasia and ossifying fibroma were 7.0％, 8.6％, respectively.

• Journal of dental hygiene science
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• v.6 no.2
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• pp.101-105
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• 2006

To conduct this study, researchers personally visited two maternity hospitals, one public centers, and two gymnastics classes for pregnant women in some areas of Seoul from March 14 to April 28, 2005 to determine a simplified oral hygiene index to measure cleanness for 200 women in the twenty weeks and over of pregnancy in order to examine their oral health conditions and provide basic data for the future oral health care and education in oral hygiene for pregnant women and, consequently, drew the following conclusions. 1. Simplified oral hygiene index between early, middle, and late pregnancy. It was shown that the Early was $1.10{\pm}.91$, Middle was $1.78{\pm}1.02$, The simplified oral hygiene index of Late was $1.73{\pm}1.03$. The simplified oral hygiene index of Total was $1.47{\pm}1.03$, with a Food debris index $0.96{\pm}0.51$ and a Calculus score $0.51{\pm}0.52$. 2. There were statistically significant differences in the simplified oral hygiene index of both the upper and the lower jaws between early, middle, and late pregnancy (p < 0.01). It was shown that the Food debris index, Calculus score, and the simplified oral hygiene index all increased with the approach of delivery. 3. There were statistically significant differences in the simplified oral hygiene index of both the anterior and the posterior areas between early, middle, and late pregnancy (p < 0.01). It was found that the Food debris index, Calculus score, and the simplified oral hygiene index all increased with the approach of delivery.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.3
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• pp.403-408
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• 2005

Ankylosis is defined as a fusion of cementum or dentine with alveolar bone. Due to the loss of the periodontal ligament on the ankylotic area, the tooth is incapable of continued eruption and hence is unable to follow the normal vertical development of the neighboring teeth and alveolar process. A 6-year-old female was referred to the Dept. of Pediatric Dentistry for ankylosis of primary molars and congenital missing of permanent premolars on both jaws. She had neither specific past medical history nor trauma and infection history in oral and maxillofacial region. Radiographic finding is that the maxillary primary molars were the early onset of ankylosis and had fast root resorption rate. However the mandibular primary molars were ankylosed later and being resorbed slower than maxillary primary molars. The object of treating this case is to maintain the proper alveolar bone growth and retention of deciduous molars. The point of managing this case is as follows: Proper treatment (observation, restoration, or extraction) should be established after thorough consideration of the time of onset, the root resorption rate, progression of infraocclusion and the development of alveolar bone support. We should consider the timing of extraction of the ankylosed teeth without problem of neighbouring alveolar bone growth and tilting of adjacent teeth in the view of growth spurt. Early diagnosis is important to avoid many of the complications with infraoccluded primary molars.

• Journal of Microbiology
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• v.45 no.3
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• pp.246-255
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• 2007

Mutans streptococci have been implicated as cariogenic bacteria in dental caries because they can produce high levels of dental caries-causing lactic acid and extracellular polysaccharide. The aim of this study was to isolate and characterize the mutans streptococci from the dental plaque obtained from Koreans. The dental plaque samples were collected from the anterior and molar teeth of both jaws in 155 subjects (aged 2 to 33.2 years, average age $13.7{\pm}4.7\;years$). The samples were diluted by 100-fold in $1{\times}\;PBS$ and plated on mitis-salivarius bacitracin (MSB) agar plates. The mutans streptococci grown on MSB plates were screened by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) targeting dextranase gene (dex). The mutans streptococci were identified at the species level using a 16S rDNA sequencing comparison method. The biochemical tests were carried out to biotype the mutans streptococci. Ninety-five strains of the mutans streptococci out of 358 colonies, which were derived from 141 subjects, were isolated. Of them, 77 strains and 18 strains were Streptococcus mutans and Streptococcus sobrinus, respectively. The biotyping data showed that 62, 1, 20, 10, and 2 strains were biotypes I, II, IV, V and variant, respectively. Of the two strains of variant biotype, one strains was similar to biotype IV except that it was positive to the arginine hydrolysis test. We considered this one strain a new biotype, and classified it as biotype VII. In conclusion, S. mutans and its biotype I was most frequently isolated in Korean dental plaque. The mutans streptococci strains isolated in this study might be useful for the study of the pathogenesis and the prevention of dental caries.

• Journal of Periodontal and Implant Science
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• v.51 no.4
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• pp.264-275
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• 2021

Purpose: Periodontitis is considered a local risk factor for medication-related osteonecrosis of the jaws (MRONJ). However, little is known about the progression of periodontitis in the presence of zoledronic acid (ZOL). The aim of this study was to evaluate the effects of the systemic use of ZOL on the progression of experimental periodontitis (EP) in rats, as ZOL could modulate the progression of periodontitis and concomitantly cause MRONJ in individuals with periodontitis. Methods: Forty-eight male Wistar rats were randomly distributed in 6 groups (n=8 each). To induce EP, ligatures were placed around the right first mandibular molars. Three groups were treated with ZOL (0.15 mg/kg/week, intraperitoneal), and 3 with 0.9% saline solution (controls). In the ZOL/Lig30 and ZOL/Lig 15 groups, after 4 weeks of treatment with ZOL, EP was induced and euthanasia was performed after 30 and 15 days of EP induction, respectively. In both groups, the animals continued to receive ZOL after EP until the end of the experiment. In the Lig/ZOL group, EP was induced first, and 15 days later, ZOL was administered for 8 weeks, with euthanasia 1 week after the last dose. After euthanasia, the mandibles were evaluated using micro-computed microtomography (micro-CT) and histomorphometry. Bone loss was measured, and the presence of osteonecrosis was evaluated histologically. The data were evaluated using the Student t-test and the Mann-Whitney test, with a significance level of 5%. Results: In the Lig/ZOL group, micro-CT revealed less alveolar bone resorption in the distal root (P<0.01) than in the control group (Lig/Con). Histomorphometric analysis confirmed less alveolar bone resorption in the Lig/ZOL group (P=0.001). Histologically, osteonecrosis was more common in the ZOL groups. Conclusion: ZOL decreased alveolar bone resorption in rats with EP. However, it presented a higher risk for MRONJ.

• Therapeutic Science for Rehabilitation
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• v.10 no.1
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• pp.53-61
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• 2021

Introduction : OMFT is a therapeutic technique based on sensorimotor, motor control and motor learning, and its major goal is to improve oral motor function. The oral motor conceptual hierarchical development is divided into 5 steps: 1) sensorimotor, 2) movement integration, 3) structural movement, 4) functional oral motor, and 5) comprehensive oral motor. Discussion : The OMFT consists of 3 techniques, 10 categories, and 50 sub-item. 1) Warming up technique: 2 categories, 12 sub-item, warming up by sensory awareness and adaptation, therapy situation adaptation, neck movement; 2) Key point technique: 7 categories, 30 sub-item, oral motor facilitation and increasing chewing skill by direct stroke of oral structures such as the face, lips, cheeks, gum, jaws, and tongue; 3) Application technique: 1 category, 8 sub-item, facilitate food intake and swallowing. Conclusion : The goal of this article is to introduce 3 techniques, 50 sub-item of OMFT, as a comprehensive oral motor therapy method, for application to clients. This article provides information that will help oral motor specialists in treating clients with oral motor problems more effectively and professionally.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.141-147
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• 2023

The genus Cottiusculus Jordan and Starks 1904 (Cottoidei: Cottidae) comprises four species worldwide, three species in Japan, and two species in Korea. Cottiusculus species are characterized by a compressed head and body without scales, except for lateral-line scales, a preopercle with four spines, a curved uppermost preopercular spine with small dorsal spines, and teeth on the upper jaws, vomer, and palatines. Two Cottiusculus species have been recorded in Korea: Cottiusculus gonez and Cottiusculus nihonkaiensis. Among these, "jeom-jul-hoet-dae" specimens were initially identified as Cottiusculus schmidti by many Korean Ichthyologists. However, since C. nihonkaiensis was reported by Kai and Nakabo (2009), most such specimens have been identified as C. nihonkaiensis. To clarify the taxonomic status of "jeom-jul-hoet-dae", we conducted morphological and molecular analyses collected from the coasts of South Korea, and compared our findings with previous reports. Japanese and Korean C. nihonkaiensis specimens mostly consistent in some proportional measurements, our molecular results indicate that they are the same species. C. nihonkaiensis, "jeom-jul-hoet-dae" distinguished from other congers by combination of following characters: simple nasal spines, two branched cirri at the upper jaw, cirri at the opercular, preopercular, and lateral lines, and a number of blotches below the lateral line.