• The korean journal of orthodontics
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• v.51 no.1
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• pp.23-31
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• 2021

Objective: To evaluate the mandibular buccal shelf (MBS) in terms of the angulation and bone depth and thickness according to sex, age, and sagittal and vertical skeletal patterns in a Colombian population using cone-beam computed tomography (CBCT). Accordingly, the optimal site for miniscrew insertion in this area was determined. Methods: This descriptive, retrospective study included 64 hemi-arches of 34 patients. On CBCT images, the angulation, buccal bone depth (4 and 6 mm from the cementoenamel junction [CEJ] of MBS), and buccal bone thickness (6 and 11 mm from the CEJ of MBS) were measured at the mesial and distal roots of the mandibular first and second molars. Results: There were no statistically significant differences in the angulation, depth, and thickness of MBS between male and female patients. The values for the bone around the distal root of the mandibular second molar were significantly greater than the other values. The osseous characteristics were significantly better in participants aged 16-24 years. Class III patients exhibited the best osseous characteristics, with the bone depth at 6 mm being significantly different from that in Class I and Class II patients. Although values tended to be greater in patients with low angles, the difference was not statistically significant. Conclusions: MBS provides an optimal bone surface for miniscrew insertion, with better osseous characteristics at the distal root of the mandibular second molar, 4 mm from CEJ. Adolescent patients, Class III patients, and patients with a low angle exhibit the most favorable osseous characteristics in the MBS area.

• The korean journal of orthodontics
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• v.32 no.1 s.90
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• pp.33-42
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• 2002

This study was performed to compare the pattern of dentoalveolar characteristics in different vertical and anteroposterior skeletal types in skeletal Class III malocclusion. The samples selected for this study were consisted of 60 subjects(29 males and 31 females, mean age; 19.7 years) in Class III group, 43 subjects(14males and 29 females, mean age : 20.5 years) in normal group. The findings of this study were as follows : 1. The IMPA of the Class III group was smaller than that of the Class I group(p<0.01). 2. In the Class III groups, SNB and NtoPog had negative correlation with IMPA(p<0.01). The SNB and NtoPog had correlations with SNU1, FHU1 and PalU1(p<0.01) in the male samples, and in the female samples, the SNB and NtoPog had correlations with SNU1(p<0.01). 3. In the Class III male samples, SNMP, FMA, PalMP had negative correlation with IMPA(p<0.01). SNMP, FMA, PalMP had not significant correlation with SNU1, FHU1, PalU1. In the Class III female samples, FMA, PalMP had negative correlation with IMPA(p<0.01). 4. In the high angle group of Class III samples, SNU1, IMPA is smaller than that of low angle group of Class III samples(p<0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.2
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• pp.136-143
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• 2015

Interest in orthodontic treatment has increased. Consequently, the percentage of the orthodontic treatment in pediatric dentistry has also increased. Given this background, the purpose of this study was to analyze the characteristics and the trends of pediatric orthodontic patients of Chonnam National University Dental hospital. A total of 670 patients (349 male, 321 female) diagnosed with orthodontic problems during the period from January 1st, 2004 to December 31st, 2014, were analyzed. The number of pediatric orthodontic patients was high in January, February, July and August. When it comes to age, the percentage of the patients who were eighty-years old accounted for the largest age group with 19.6%, followed by seven-year, nine-year, ten-year, eleven-year, and six-year old age groups. Skeletal class 1 accounted for 48.1% of the total cases, followed by class 2 (28.7%) and class 3 (23.3%). Mesofacial type accounted for 65% of the total cases, followed by dolichofacial type (19.3%) and brachyfacial type (15.8%). The period of the first phase orthodontic treatment was steadily shortened from 30.4 months in 2004 to 11.5 months in 2013. The result of this study is expected to provide information of the pediatric orthodontic patients.

• Food Science of Animal Resources
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• v.38 no.4
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• pp.711-717
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• 2018

Myogenic factor 5 (MYF5) plays an important role in regulating skeletal muscle fiber characteristics, consequently affecting meat production and quality. We identified a novel p.A41P mutation in exon1 of the porcine MYF5 gene by direct sequencing. The mutation was predicted to be destabilizing in protein structure based on the resultant amino acid substitution. We estimated the significant substitution effect of p.A41P on the energy stabilization of Myf5 protein structure. Then, we demonstrated that the mutation in Yorkshire population significantly affected muscle fiber type I composition (p<0.05), loin-eye area of lean meat content (p<0.05) and filter-fluid uptake of meat quality (p<0.01). Furthermore, dominant effects significantly influenced total muscle fiber number (p<0.05). This study suggests that the novel p.A41P mutation in porcine MYF5 may be a valuable genetic marker to affect the muscle fiber characteristics and consequently improve meat production quality and quantity.

• The korean journal of orthodontics
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• v.25 no.6 s.53
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• pp.665-674
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• 1995

The purpose of this study is to investigate the cephalometric characteristics of the open-bite patients with DJD of TMJ. The DJD open-bite cases were compared with normal samples and Class II open-bite cases with normal TMJ respectively. Twenty three open-bite patients with bilateral DJD of TMJ($13.9\~35.3$ yens old, Group I) were selected from the Department of Orthodontics, SNUDH. Group ll consisted of thirteen Class II open-bite cases($13.2\~27.4$ years old) with no TMD signs/symtoms and good condylar shapes. Group III samples were the forty eight healthy dental students who have Class I molar relationships with no history of orthodontic treatment, good facial balance and no TMD symptoms($20.0\~26.8$ years old). First, sixty measurements in the lateral cephalometric radiographs and analysis of variance(P<0.05, Scheffe) were used to compare these three groups. The seven measurements showed significant difference(p<0.05) between Group I and Group II. After analysis of variance, six of them were used for the discriminant analysis(Wilks' stepwise analysis) and the discrminant function for Group I/Group II was obtained. The results and conclusions were as follows : In most of the measurments, Group I and Group II showed the same skeletal and dental characteristics. But seven of the sixty measurements(FH-PP angle, SNB, FH-ArGo angle, articulare angle, genial angle, upper gonial angle and Ar-Go length) were significantly different(p<0.05) between Group I and Group II. These differences may be explained by the fact that in DJD cases the mandible rotated backward due to the shortening of the ramus following the degenerative destruction of condylar head and its surrounding structures. The resulting discriminant function was : $D={-0.120X}_1+{0.066X}_2+{0.144X}_3-{0.058X}_4+2000,\;where\;X_1=ArGo\;length(mm),\;X_2=SArGo\;angle(degree),\;X_3=FH-PP\;angle(degree),\;X_4=Gonial\;angle(degree)$. Mean of the group centroids was -0.555 and percent of the 'grouped' cases correctly classified was $88.89\%$.

• Clinical and Experimental Pediatrics
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• v.58 no.12
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• pp.478-483
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• 2015

Purpose: Information on the clinical features of lung abscess, which is uncommon in children, at hospitalization is helpful to anticipate the disease course and management. There is no report concerning lung abscess in Korean children. We aimed to identify the clinical characteristics of pediatric lung abscess and compare the difference between primary and secondary abscess groups. Methods: The medical records of 11 lung abscess patients (7 males and 4 females) from March 1998 to August 2011 at two university hospitals were retrospectively reviewed. The clinical characteristics, symptoms, underlying disease, laboratory and radiologic findings, microbiological results, and treatments were examined. Results: Six patients had underlying structural-related problems (e.g., skeletal anomalies). No immunologic or hematologic problem was recorded. The mean ages of the primary and secondary groups were 2.4 and 5.3 years, respectively, but the difference was not statistically significant. The mean length of hospital stay was similar in both groups (22.8 days vs. 21.4 days). Immunologic studies were performed in 3 patients; the results were within the normal range. Most patients had prominent leukocytosis. Seven and 4 patients had right and left lung abscess, respectively. Staphylococcus aureus, Streptococcus pneumoniae, and antimycoplasma antibodies were detected in both groups. Two patients with primary lung abscess were administered antibiotics in the absence of other procedures, while 8 underwent interventional procedures, including 5 with secondary abscess. Conclusion: The most common symptoms were fever and cough. All patients in the primary group were younger than 3 years. Structural problems were dominant. Most patients required interventional procedures and antibiotics.

• Journal of Trauma and Injury
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• v.26 no.3
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• pp.125-130
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• 2013

Purpose: This study was undertaken in order to identify the characteristics of patients diagnosed with occult an hip fracture after hip trauma. Methods: We retrospectively reviewed the medical records and radiology reports of all patients who underwent hip skeletal computed tomography (CT) for suspected hip fractures but had normal initial X-rays after hip trauma between August 2006 and January 2012. The variables evaluated included age, gender, body mass index (BMI), accident mechanism, previous fracture, independence, late presentation, ability to bear weight, pain on passive rotation, tenderness of the groin area, diagnosis and treatment. Patients were divided into two groups, with hip fracture (occult hip fracture group) and without hip fracture (no fracture group) to evaluate the characteristics associated with an occult hip fracture. Results: The patients, a total of 139, had a mean age of 58.3 years and included 72 male patients(51.8%). The occult hip fracture group included 43 patients(30.9%). Of those 43, 21 patients(48.8%) had intertrochanteric or trochanteric fractures, 8 patients(18.6%) had femur neck fractures and 14 patients(32.6%) had acetabular fractures. Of the 43, 15 patients(34.9%) needed operative treatment. Age was higher in the occult hip fracture group than it was in the no fracture group($64.4{\pm}19.1$ years vs. $55.5{\pm}23.6$ years, p=0.021). A previous fracture was associated with the presence of a new fracture (p=0.014; OR=3.971, 95% CI=1.314-11.997). Conclusion: Further evaluation of patients who are older or have history of fractures is prudent, even though the initial X-rays are normal.

• Imaging Science in Dentistry
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• v.36 no.2
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• pp.95-101
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• 2006

Purpose : Bony strength is dependent on bone mass and bony structure. So this study was designed to investigate the relationship between the bone mass and bony trabecular characteristics. Subjects and Methods : Study subjects were 51 females (average age 68.6 years) and 20 males (average age 66.4 years). Bone mineral density (BMD, $grams/cm^2$) of proximal femur was measured by a dual energy X-ray absorptiometry (DEXA). Regions of interest (ROIs) were selected from the digitized radiographs of proximal femur. A customized computer program processed morphologic operations (MO) of ROIs. 44 skeletal variables of MO were calculated from ROIs on the Ward's triangle and greater trochanter of femur. WHO BMD classes were predicted by MO variables of the same ROI. Classification and Regression Tree analysis was used for calculating weighted kappa values, sensitivity and specificity of MO. Results : The discriminating factors of morphologic operation were branch point, branch point [per cm sq]. Age also played important role in distinguishing osteoporotic classes. The sensitivity of MO at Ward's triangle and Greater Trochanter was 91.8%, 65.6%, respectively. The specificity of MO was 100% at Ward's triangle and Greater Trochanter. Conclusion : Bony trabecular characteristics obtained using radiological bone morphometric analysis seem to be related to bone mass.

• Journal of Korean Institute of Industrial Engineers
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• v.23 no.4
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• pp.779-791
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• 1997

The purpose of this study is to measure a perceived joint discomfort in the seated and standing position, and to provide ranking systems of perceived joint discomfort. Nineteen mole subjects with no history of musculo-skeletal disorders participated in the experiment. Their physical characteristics were: age $-25.4{\pm}2.7$years, stature $-171.9{\pm}6.0cm$, and body weight $-67.1{\pm}7.0kg$. The results showed that the perceived joint discomforts were different depending upon the joints involved in motion and their movement directions (degree of freedom of motions), which implied that the human body motions and their degrees of freedom should be classified into several distinct classes that need to be assigned different weights of postural stress. Therefore, three ranking systems based on the perceived joint discomforts were suggested, which were classified by the degree of freedom of motions and joints, by only degree of freedom motions, and by joints involved in motion, respectively. In the seated position, the hip movement was the most stressful, the bock was the second, and the shoulder was the third. Likewise, in the standing postures, the hip was the most, the bock was the second, and the ankle was the third. It was expected that these joint motion ranking systems could be used by practitioners of health and safety to improve the comfort of working postures in industry.

• Health Policy and Management
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• v.12 no.1
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• pp.125-143
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• 2002

The objectives of this study were analysis of patient\`s characteristics and market segmentation in oriental medical care and western medical care. This study focused on medical utilization using Anderson's health utilization model. The source of data was 1998 National Health and Nutrition Survey which Korean Institute For Health and Social Affairs carried out. A stratified multistage probability sampling design was used in this survey. The analysis was conducted using the statistical software package SPSS version 10.0 and Answer Tree 2.1 which is one of data mining methodology. The results were as follows ; 1) 44.9% of respondents reported visiting oriental medical center within recent two weeks. 3.4% of them used oriental medical care. The group of age, kind of disease and medical expenditure are associated with the difference western and oriental medical utilization rate. 2) There were several factors related to utilization of oriental medical care according to decision tree. Especially, important factors that patient chose his medical center were kinds of disease, kinds of common medical use, and expenditure. 3) in the results of CART analysis, market of oriental medical care were classified by seven categories. The major groups who have a preference for oriental medicine were those musculo-skeletal, cerebra-vascular disease, or chronic headache patients, and they had a preference fur oriental medical care in common use. These results show that oriental and western medical market were divided into various areas by market segmentation.