• Journal of the Korea Construction Safety Engineering Association
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• s.22
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• pp.52-61
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• 1996

다음은 지난해 12월 12일 국제빌딩 회의장에서 노동부 주최, 한국산업안전공단ㆍ한국건설가설협회 주관으로 열린 <가설재해예방과 업계 방전을 위한 세미나> 중 발표된 내용으로서 각계 - 정부측(노동부), 학계, 가설재 제조업계, 가설재 임대업계, 사용자인 건설업계 - 의 의견을 발췌한 것이다.

• The Journal of the Korean dental association
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• v.21 no.12 s.175
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• pp.985-990
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• 1983

320 cephalometric roentgenograms of 25 boys and 15 girls which was longitudinally taken from the age 6.5 to 13.5 have been analyzed to access the angular growth changes of the mandible. The statistical analysis of the results allowed the following conclusions. 1. Gonial angle was reduced with ageing. 2. Chin angle was reduced with ageing. 3. Occlusal plane to mandibular plane angle was relatively stable. 4. Lower incisor to occlusal plane angle was reduced and showed the greatest variability.

• The korean journal of orthodontics
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• v.30 no.1 s.78
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• pp.53-66
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• 2000

This study was performed to find out the effect of projection errors on cephalometric linear and angular measurements according to head rotation during taking lateral cephalometric radiographs. Seventeen skulls with permanent dentition and no gross asymmetry were obtained from the Department of Anatomy, Medical School, Chosun University. Total 527 x-ray films were taken with $1^{\circ}$ interval from the reference position($0^{\circ}$) to ${\pm}15^{\circ}$ around the vertical axis (Z axis) which is perpendicular to the midpoint of the line connecting the center of two ear rods in submento-vertex direction. Statistical analysis was performed by paired t-test if there were statistically significant differences between the mean of the reference position($0^{\circ}$) and that of each rotation angle. The following results were obtained. 1. The projection errors of angular measurements were smaller than those of linear measurements. 2. The projection errors of angular measurements including midline landmarks were smaller than those including bilateral landmarks. 3. The horizontal linear measurements were gradually decreased when the stroll was rotated toward the film, but slightly increased and then decreased when the skull was rotated toward the focal spot. However, the changes were smaller in focal direction. 4. The projection errors of horizontal linear measurements were larger than those of vertical linear measurements. 5. The projection errors of vertical linear measurements were increased with increased distance from the rotation axis to vertical measurements. It is concluded that the use of angular measurements rather than linear measurements is recommended to minimize the projection errors.

• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.301-309
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• 2001

Because many of patients seeking orthodontic treatment worry about the facial appearance and their chief motivation for orthodontic treatment is facial esthetics, it is critical to understand the influence of gender or culture on the evaluation of profile esthetics. The purpose of this study was to find out any influence of gender or culture on judging good facial profile. 4 different groups were asked to evaluate 133 facial profiles to test the influence of gender or culture on judging good facial profiles. Those 4 groups consisted of 10 Korean males, 10 Korean females, 10 Korean American males, and 10 Korean American females. 2 evaluation systems were introduced, absolute and relative. Soft tissues of selected good profile group were analyzed and statistic analysis was performed. Conclusions were as follows 1. Inter-evaluator difference for judging good facial profile was statistically significant, even if there was general agreement for the best profile among 40 raters. 2. Gender difference under the same cultural environment was not significant statistically. 3. The same ethnic groups with different cultural background showed statistically different preference on judging good Profile. 4. Good facial profile group had their own characteristics compared to remaining group in several soft tissue measurements which were vertical facial ratio, soft tissue facial convexity, and antero-posterior relative lip position.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.1
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• pp.185-194
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• 2001

This study was designed to evaluate the effects of angulation changes of head posture on the enlargement ratios of a lateral headfilm depending on the vortical or horizontal rotation of the objects. A device was constructed to measure regional changes of enlargement ratios. The device was held within the cephalostat and cephalograms recorded at each measured degrees of the device tilting, vertically and horizontally. The enlargement ratios of the horizontal, vertical, and angular measurements on the films taken at each tilted angulations were obtained and compared with those on the films taken without rotation. In summary, the enlargement ratios of the horizontal linear measurements were decreased during horizontal rotations. The enlargement ratios of vortical measurements of the right side on the film were increased and those of the left side were decreased by the horizontal rotations. Enlargement ratios of horizontal measurements were affected further than those of vertical measurements by the same angular changes of the horizontal rotations. Therefore, a disruption of parallelism between the object's midsagittal plane and the film could result in distortion of the image while vertical rotation around the object's porionic axis would not significantly affect the enlargement ratios on the headfilm.

• The korean journal of orthodontics
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• v.17 no.2
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• pp.255-277
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• 1987

부정교합(不正交合)의 발생요인(發生要因)의 하나로서 비인두강(鼻咽頭腔)의 협착(狹窄)이 거론(擧論)되어 왔다 본(本) 연구(硏究)는 안면골격(顔面骨格)의 형태결정(形態決定)에 비인두강(鼻咽頭腔)의 기여정도(寄與程度)를 파악(把握)하고자 함에 있다 연구자료(硏究資料) 및 방법안(方法安) 한국인(韓國人) 성인(成人) 남녀(男女) 156 명(名)의 측모두부X선규격사진(側貌頭部X線規格寫眞)을 사용(使用)하여 NEC PC-9801 VM2 Personal Computer와 Oscon GT-4000 Digitizer에 의한 data 입력(入力)을 행(行)한 후 통계처리(統計處理)를 행(行)하였다 통계처리(統計處理)로서는 각계측치(各計測値)에 대하여 남녀별(男女別)로 평균치(平均値), 표준편차치(標準偏差値)를 산출(算出), Student's t-test를 행(行)하고, 비인두강(鼻咽頭腔) 계측항목(計測項目)과 안면골격(顔面骨格)의 각(各) 계측치간(計測値間)의 상관관계(相關關係)의 검토(檢討)를 행(行)하였다 결(結) 과(果) 1 남녀(男女)의 성차(性差)로서, 여자(女子)보다 남자(男子)가 상악골(上顎骨)에 대해 하악골(下顎骨)이 돌출(突出)되어 있었으며, 안면고(顔面高)가 컸다 2 Ba-S-PNS와 S-PNS-Ba간(間)에 부(負)의 상관(相關)이 인정(認定)되어, 이 두 계측치간(計測値間)애 상호작용(相互作用)이 있는 것으로 판단 되었다 3 비인두강(鼻咽頭腔)의 깊이는 하악(下顎)의 전후위치관계(前後位置關係)와 유의(留意)한 상관관계(相關關係)를 보였다 4 비인두강(鼻咽頭腔)의 깊이와 안면(顔面)의 깊이와는 관련성(關聯性)이 없는 것으로 판단 되었다 5 비인두강(鼻咽頭腔)의 깊이와 안면고간(顔面高間)에 유의(有意)한 부(負)의 상관(相關)이 시사(示唆)되었다 6 비인두강(鼻咽頭腔)의 고경(高經)과 안면고간(顔面高間)에 유의(有意)한 상관관계(相關關係)가 인정(認定)되었다.

• The korean journal of orthodontics
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• v.28 no.6 s.71
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• pp.937-946
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• 1998

The patient with an anterior open bite has one of the most difficult orthodontic problem to correct. Previous studies have yielded different conclusions as to exactly where the morphologic problems associated with vertical dysplasia-high angle cases are located. In order to identify the cephalometric features of high angle cases and highlight the measurements that characterize high angle cases, 109 pretreatment cephalograms, 35 high angle, 37 average angle, and 37 low angle cases, were analyzed and compared statistically. As the mandibular plane was steeper, the anterior facial height, especially lower anterior facial height, became greater, and the posterior facial height became smaller. All the dentoalveolar vertical dimensions, especially in upper, increased. And all the skeletal angular measurements increased. Especially Lower genial angle had most positive correlation to mandibular Plane angle. Upper incisor was lingually inclined, and lower incisor was labially inclined in high angle cases.