• 대한치과교정학회지
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• 제10권1호
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• pp.15-27
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• 1980

This study was undertaken to compare the craniofacial morphology of Class II, Division 1 malocclusion with that of normal occlusion in children, and to investigate the incidence of various Class II, Division 1 craniofacial skeletal patterns. The subjects consist of thirty seven boys and fifty three girls with Class II, Division 1 malocclusion, and forty six boys and eighty one girls 10-15 years with normal occlusion. Measurements were recorded, tabulated and analyzed on the lateral cephalograms by the degree of SNA, SNB and ANB. The following characteristics of the Class II, Division 1 skeletal pattern were observed. 1. The anteroposterior relationship of the maxilla to the cranium in the Class II, Division 1 was very similar to that of normal occlusion. 2, Mandible of the Class II, Division 1 malocclusion was in the posterior position in relation to the cranial anatomy when compared to normal. 3. The chin point as measured by SN Pog and NS Gn showed distal positioning in relation to normal occlusion. 4. SN to mandibular plane angle was large in Class II, Division 1 malocclusion. 5. Mandibular incisor inclination was not significantly different between Class II, Division 1 malocclusion and normal occlusion, but maxillary incisors inclined and positioned labially and consequently overjet was large in Class II, Division 1 malocclusion. 6. Class II, Division 1 malocclusion was divided into four types of craniofacial skeletal pattern. The most common Class II, Division 1 pattern was found to be type C in which SN-Mand. Pl. was above mean range of normal occlusion. The next frequent pattern was found to be type A in which maxilla and mandible were within normal range of protrusion while upper incisors were severly labially inclined.

• 대한치과교정학회지
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• 제22권2호
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• pp.389-412
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• 1992

Along with form and function relationship of craniofacial growth comes a concern for the masticatory muscles with postnormal occlusion. It is the aim of this study to grope the certain differences upon the electromyographic activities of the masticatory muscles between normal occlusion and class II malocclusion during the varieties of oral functions. 26 persons of normal occlusion whose mean age were 18.9-25.6 years and another 26 persons of class II malocclusion whose mean age were 19.0-28.9 years served for this study. The electromyographic recordings processed by $Medelec^{\circledR}$ MS 25 EMG apparatus were taken from the anterior and posterior temporal, and anterior and posterior masseter muscles of both sides, and suprahyoid muscles as well. Analyses of the data toward such specific activities as mandibular rest, maximal biting, chewing gums and swallowing peanuts turned out the following summary and conclusions. 1. The maximal mean amplitude of the posterior temporalis showed significant augmentation in class II malocclusion, however the anterior temporalis, posterior masseter, and suprahyoid muscles manifested meaningful diminutions. 2. Stronger posterior temporalis and weaker anterior masseter and suprahyoid muscles were arranged in maximal biting with parameters of maximal mean amplitude. 3. The anterior temporalis of working side expressed smaller maximal mean amplitude in class II malocclusion. Significant swelling in duration were shown at anterior and posterior temporalis of working side, and posterior temporalis of balancing side in class II malocclusion, and marked reduction at anterior masseter of balancing side and posterior masseter of working side as well. The lessened latency were expressed at anterior masseter of working side, and anterior and posterior masseter of balancing side. Class II malocclusion group had significant prolongation of silent period duration. Mean silent period duration of 10.75 msec in normal occlusion and 24.37 msec in class II malocclusion were calculated. 4. Significant augmentations of maximal mean amplitude while swallowing peanuts were yielded at right anterior temporalis and posterior temporalis of both sides, however left anterior masseter and right posterior masseter showed diminution. No significant differences in duration showed at every muscle examined in class II malocclusion group.5. Weaker masseter and stronger temporalis were suggested as characteristics of class II malocclusion.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제37권
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• pp.25.1-25.9
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• 2015

Background: During the orthognathic surgery, it is important to know the exact anatomical location of the mandibular foramen to achieve successful anesthesia of inferior alveolar nerve and to prevent damage to the nerves and vessels supplying the mandible. Methods: Cone-beam computed tomography (CBCT) was used to determine the location of the mandibular foramen in 100 patients: 30 patients with normal occlusion (13 men, 17 women), 40 patients with skeletal class II malocclusion (15 men, 25 women), 30 patients with skeletal class III malocclusion (17 men, 13 women). Results: The distance from the anterior border of the mandibular ramus to mandibular foramen did not differ significantly among the three groups, but in the group with skeletal class III malocclusion, this distance was an average of $1.43{\pm}1.95mm$ longer in the men than in the women (p < 0.05). In the skeletal class III malocclusion group, the mandibular foramen was higher than in the other two groups and was an average of $1.85{\pm}3.23mm$ higher in the men than in the women for all three groups combined (p < 0.05). The diameter of the ramus did not differ significantly among the three groups but was an average of $1.03{\pm}2.58mm$ wider in the men than in the women for all three groups combined (p < 0.05). In the skeletal class III malocclusion group, the ramus was longer than in the other groups and was an average of $7.9{\pm}3.66mm$ longer in the men than women. Conclusions: The location of the mandibular foramen was higher in the skeletal class III malocclusion group than in the other two groups, possibly because the ramus itself was longer in this group. This information should improve the success rate for inferior alveolar nerve anesthesia and decrease the complications that attend orthognathic surgery.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권4호
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• pp.221-228
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• 2009

The purpose of the study was to investigate the characteristics of the pronunciation of Korean vowels in patients with class III malocclusion. 11 adult male patients with class III malocclusion(mean ages 22.3 years) and four adult males with normal occlusion(mean ages 26.5 years) were selected for the analysis of eight Korean monophthongs /ㅣ, ㅔ, ㅐ, ㅏ, ㅓ, ㅗ, ㅡ, ㅜ/. The values and relationships of F1, F2 and F3 were derived from the stable section of target vowel in each sentence, and the analysis using formant plots and vowel triangles' distance and area was conducted to find the features of two groups' vowel distributions. Consequently, it was identified that the pronunciation of males patients with class III malocclusion showed high values of F1 in the low vowels, high values of F2 in the back vowels, and remarkably low position of /ㅏ/. The vowel triangle suggested that the triangle areas of male patients with class III malocclusion were shown wider vertically and narrower horizontally than those of males with normal occlusion. These characteristics could reflect the structural features of class III malocclusion such as the prognathic mandible, low tongue position, and advancement of back position of the tongue.

• 대한치과교정학회지
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• 제28권2호
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• pp.255-268
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• 1998

본 연구에서는 II급 부정교합자의 교합평면의 형태적 특징을 관찰하고, 안면의 수직고경과 연관지어 정상교합군과 비교하여 교합평면의 발현에 영향을 미치는 골격성, 치성요인의 기여정도를 알아보고자 했다. 성장과 연령군의 변이를 배제하기 위해 성장이 완료된 성인만을 연구대상으로 정하였다. 정상교합자 50명과 서울대학교 치과진료부 교정과에 내원한 50명의 Angle class II 환자의 측모 두부방사선 계측사진분석을 통하여 다음의 결과를 얻었다. 1. II급 부정교합자군에서 정상군보다 유의하게 크게 관찰된 교합평면의 경사도는 다음과 같다. ; SN-FOP, FH-BOP, MP-BOP, AB-BOP, AB-FOP, Facial plane-BOP, FP-FOP 2. II급 부정교합자군에서는 정상군에 비해 후안면 고경, 특히 후하안면고경이 유의한 차이를 보였다. 3. 교합평면과 상하악 전치가 이루는 각은 II급 부정교합군에서 통계적으로 유의하게 컸고, 대구치와 이루는 각은 상악 대구치와 해부학적 교합평면이 이루는 각만이 통계적으로 유의한 차이를 나타냈다. 4. 교합평면의 위치를 결정하는 요소중에서 하악절치에서 하악평면에 이르는 거리만이 II급 부정교합군에서 유의하게 컸다. 5. III급 부정교합군에서는 수직피개도와 교합평면 경사도의 상관관계가 존재하지만, 정상 교합군에서는 수직피개도와 교합평면 경사도간에 상관관계가 존재하지 않았다.

• 대한구순구개열학회지
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• 제14권1_2호
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• pp.1-18
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• 2011

Skeletal malocclusion is the result of abnormal dimension and alignment of each skeletal component. Understanding on these mechanisms may help to elucidate the etiology of skeletal malocclusion and to establish population-oriented treatment plans. Attempts to subdivide the Angle's classification have been performed for Class III malocclusion, while few studies have been conducted for Class II malocclusion despite recent growing interests in Class II malocclusion. 200 adults (88 male, 112 female) with skeletal Class II malocclusion were collected and subdivided using cluster analysis, using the measurements representing the dimension and the alignment of each facial skeletal component. The properties of each cluster was grouped within the subjects and a comparison between the subjects and the control group (38 male, 35 female) with normal occlusion was performed. Six clusters were finally recognized in each male and female groups. The clusters in both genders were mainly characterized by the cranial base alignment, dimension of the posterior cranial base, dimension of the mandibular ramus and the degree of mandibular rotation. The results implicate that active treatment of mandible rather than the nasomaxillary complex may be primarily considered for the correction of Korean Class II skeletal pattern.

• 대한치과교정학회지
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• 제25권4호
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• pp.453-463
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• 1995

측모두부 방사선 계측사진에서 일반적으로 사용하는 상악 중절치의 장축은 치근첨(Root Apex)과 절치단(Incisor Edge)를 연결한 선을 사용하지만 일부 부정교합 환자에서는 치관장축과 치근장축이 일치하지 않는 경우가 있으며 이 경우 두장축이 이루는 각을 치관-치근각도(Collum Angle)라 하며, 이 각도는 교정치료의 진단 및 치료과정에 고려되어져야 한다. 본 연구에서는 제 I 급 부정교합 환자 31명, 제 II급 1류 부정교합 환자 30명, 제 II 급 2류 부정교합 환자 31명, 제 III급 부정교합 환자 31명에서 치관-치근 각도를 계측하여 부정교합과의 상관관계를 알아보았으며, 측모두부 방사선 계측사진에서 사용되는 항목들과의 상관분석을 통하여 다음과 같은 결론을 얻었다. 1. 부정교합 분류에 따른 치관-치근 각도의 평균값은 제 I 급 부정교합에서는 $3.11^{\circ}{\pm}3.54^{\circ}$, 제 II급 1류 부정교합에서는 $1.23^{\circ}{\pm}2.41^{\circ}$, 제 II급 2류 부정교합에서는 $3.77^{\circ}{\pm}4.39^{\circ}$, 제 III급 부정교합에서는 $3.90^{\circ}{\pm}4.08^{\circ}$ 이었다. 2. 제 II급 1류 부정교합군의 치관-치근 각도와 제 II급 2류, 제 III급 부정교합군의 치관-치근 각도에 유의성 있는 차이가 나타났다. 3. 치관-치근 각도와 측모두부 방사선 계측사진에서 사용되는 다른 항목들과의 상관관계에서 제 I급 부정교합에서는 IMPA, 제 II급 1류 부정교합에서는 Wits, 제 II급 2류 부정교합과 제 III급 부정교합에서는 Overbite이 가장 큰 상관성을 보였다.

• 대한치과교정학회지
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• 제15권1호
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• pp.85-92
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• 1985

This investigation was designed to compare the craniofacial morphology of Class III malocclusions with that of normal occlusions using PM line. The subjects consisted of forty-four normal occlusions (twenty-three males and twenty-one females) and sixty-nine Class III malocclusions (thirty males and thirty-nine females), aged eight through ten. Using the tracings of the standard lateral cephalograms, various angles, linear measurements and linear ratios of counter-part were recorded and analyzed by t-test. The following characteristics of craniofacial morphology of Class III malocclusion were obtained by this study. 1. Maxillary anteroposterior position was balanced with Nasion but was not balanced with mandible because maxillary bony arch was small and positioned posteriorly and mandibular corpus was large and positioned relatively anteriorly. 2. Upper and lover alveolar bony arch were not balanced each other in its size. 3. In counterpart analysis, Class III malocclusion was more horizontally unbalanced than normal occlusion. 4. Class III malocclusion was divided into 11 groups by maxillary and mandibular bony arch position, size and alveolar bony arch size. Unbalanced bony size of the maxilla and mandible was a major characteristics of Class III malocclusion.

• 대한치과교정학회지
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• 제53권2호
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• pp.67-76
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• 2023

Objective: Morphometric and morphological evaluation of the mandibular condyle in adults and to identify its correlation with skeletal malocclusion patterns. Methods: Cone-beam computed tomography scans of 135 adult patients were used in this study and classified into groups according to four criteria: (1) sex (male and female); (2) sagittal skeletal discrepancy (Class I, Class II, and Class III); (3) vertical skeletal discrepancy (hyperdivergent, normodivergent, and hypodivergent); and age (group 1 ≤ 20 years, 21 ≤ group 2 < 30, and group 3 ≥ 30 years). The morphometrical variables were mandibular condyle height and width, and the morphological variable was the mandibular condyle shape in coronal and sagittal sections. Three-dimensional standard tessellation language files were created using itk-snap (open-source software), and measurements were performed using Meshmixer (open-source software). Results: The mandibular condyle height was significantly greater (p < 0.05) in patients with class III malocclusion than in those with class I or II malocclusion; the mandibular condyle width was not significantly different among different sexes, age groups, and sagittal and vertical malocclusions. There were no statistical associations between various mandibular condyle shapes and the sexes, age groups, and skeletal malocclusions. Conclusions: The condylar height was greatest in patients with class III malocclusion. The condylar height and width were greater among males than in females. The mandibular condyle shapes observed in sagittal and coronal sections did not affect the skeletal malocclusion patterns.

• 대한치과교정학회지
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• 제28권5호
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• pp.865-875
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• 1998

교정이나 악교정 수술 환자에서 치료계획 수립과 치료결과의 평가를 위해서 지금까지 많은 수평기준선이 사용되고 있으나 정확성과 재현성 등의 문제가 존재하고 있으며, 더욱 객관적인 수평기준선이 설정 될 수 있다면 교정학 분야에서 많은 발전이 기대될 수 있을 것이다. 이에 본 연구에서는 한국 성인의 부정교합군과 성별에 따른 Sella-Nasion(SN) 평면과 Frankfort-Horizontal(FH) 평면이 이루는 각도 및 FH평면과 다른 수평면 간의 상관 관계를 조사하기 위하여 먼저 임상검사를 시행하여 총 600 여명을 대상으로 측모두부규격 방사선사진을 촬영하였다. 계측결과를 바탕으로 연구대상을 골격성 I급 부정교합군 또는 정상교합군(남 50, 여 50), 골격성 II급 부정교합군(남 50, 여 65), 골격성 III급 부정교합군(남 50, 여50)으로 분류한 후 10개의 항목을 평가하여 다음과 같은 결론을 얻었다. 1. SN평면과 FH평면이 이루는 각도는 부정교합에 따른 차이는 없었으나 성별 간에는 세 부정교합군 모두에서 차이를 보여 남자는 $7.47{\pm}2.40^{\circ}$, 여자는 $8.93{\pm}2.72^{\circ}$ 였다. 2. SN 평면 또는 FH 평면과 Mandibular Plane이 이루는 각은 모든 부정교합군에서 여자가 남자보다 컸으며, 골격성 II급 부정교합군과 III급 부정교합군이 I급 부정교합군보다 큰 각도를 나타내었다. 3. FH평면과 Palatal Plane이 이루는 각은 부정교합군 및 성별에 따른 차이를 보이지 않고 비교적 일정하였다. 4. Gonial angle은 남녀 모두 III급 부정교합군이 다른 두 부정교합군보다 큰 각도를 보였다.