• The korean journal of orthodontics
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• v.25 no.5 s.52
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• pp.577-585
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• 1995

This study has been performed to determine whether significant differences in the maxillary basal bone pattern exist between skeletal class II malocclusion and normal occlusion. Materials for the skeletal Class III sample consisted of lateral cephalometric roentgenograms and maxillary cast models of 29 adult individuals, 15 males and 14 females. The average age was 19.75 years with a range from 16.4 to 29.1 years. A normal control sample consisted of lateral cephalometric roentgenograms and maxillary cast models of 24 adult individuals, 13 males and 11 females. The average age was 24.25 years with a range from 20.8 to 29.4 years. The results of this study can be summarized and concluded as like follows. 1. In comparing sexual difference of maxillary basal bone morphology in skeletal Class III malocclusion, the following Parameters of males were found to be significally larger than those of females : inter first premolar width, inter molar width, oblique canine height, oblique molar height and maxillary basal bone perimeter. 2. In comparing sexual difference of maxillary basal bone morphology in normal occlusion, the following parameters of males were found to be significally larger than those of females : inter canine width, inter first and second premolar width, inter molar width, oblique canine height and oblique molar height. 3. In comparing maxillary basal bone morphologic difference between skeletal Class III malocclusion md normal occlusion in males, the following parameters were found to be significally larger in normal occlusion : inter canine width, inter canine height, inter molar height, oblique canine height and oblique molar height. 4. In comparing maxillary basal bone morphologic difference between skeletal Class III malocclusion and normal occlusion in females, the following parameters were found to be significally larger in normal occlusion : inter canine height, inter molar height, oblique canine height, oblique molar height and maxillary basal bone perimeter.

• The korean journal of orthodontics
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• v.41 no.4
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• pp.224-236
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• 2011

Objective: The purpose of this study was to analyze the dental and basal arch forms in patients with normal occlusion using the computed tomography (CT) imaging method. Methods: CT images were taken from 27 normal occlusion subjects (male, 15; female, 12) and these images were reconstructed into three-dimensional models. A 3D-coordinate system was formed by setting the middle of the facial axis (FA) point of the maxillary central incisors as the origin. The morphology of the maxilla and mandibular dental and basal arches were analyzed by sectioning parallel to the maxillary occlusal plane. Results: There was no significant difference between A point and B point and between the maxillary 1st molars in both sides of the maxillary and mandibular basal bone. The dental arch was located more labially than the basal arch in the anterior portion. The bucco-lingual crossover of the dental arch and basal arch was formed at the molar region in the maxilla, and at the premolar region in the mandible. Conclusions: This study will help provide three-dimensional diagnostic information about the relationship between basal and dental arches in patients who have severe dental compensation and inappropriate jaw relationships.

• The korean journal of orthodontics
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• v.38 no.5
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• pp.358-370
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• 2008

Objective: The purpose of this study was to investigate the horizontal skeletal pattern and dental arch differences between Class III malocclusion patients and normal occlusion patients. Methods: Twenty skeletal Class III malocclusion patients and ten normal occlusion patients were selected and 3D facial CT were taken to analyze the horizontal skeletal differences between the two groups. Results: In the horizontal comparison of the maxilla, skeletal width and perimeter were significantly smaller in skeletal Class III patients on ANS and A point reference planes. The difference between maxillary width of ANS and A point reference planes showed that there was greater constriction of the first and second premolar in skeletal Class III patients. In the horizontal comparison of the mandible, the widths of the canine and premolar area were significantly larger in skeletal Class III patients on B point reference plane. The differences between width of the upper and lower jaws (comparison of A and B reference planes) were significantly large in the canine and premolar area. Conclusions: From this study, the characteristics of Class III malocclusion patients were shown through horizontal constriction of the maxilla. But to make clear further detailed characteristics of Class III malocclusion patients, additional studies are necessary.

• The korean journal of orthodontics
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• v.29 no.2 s.73
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• pp.197-207
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• 1999

Although there is a severe underlying skeletal deformity, the dentition has often maintained some occlusal contact and interdigitation by the teeth compensating in their positions for the skeletal problem, and these dental compensations are manifested in all three planes of space. The purposes of present investigation were 1) to study the pattern of dentoalveolar compensation of hyperdivergent skeletal pattern , and 2) to compare the dentoalveolar compensations of hyperdivergent skeletal pattern in children with adults. The samples selected for this study were consisted of 60 subjects in normal group, 60 subjects in hyperdivergent group. Each was divided into two subgroups by age ; child groups($8\~12yr$ old) and adult groups(17yr old over). The findings of this study were as follows; 1. In child, hyperdivergent subjects had smaller posterior lower facial height(p<0.01) and slightly longer anterior lower facial height than normal ones. In adults, they still expressed smaller posterior lower facial height and much longer anterior lower facial height than normal ones(p<0.01). 2. Hyperdivergent subjects had larger amount of upper and lower incisor relative eruption to their basal bone length than normal ones(p<0.05). In adult, relative eruption of upper incisor was increasing(p<0.05), although relative eruption of lower incisor remained the same as the child. 3. In child, there was no difference between hyperdivergent group and nomal one in the upper and lower molar relative eruption to their basal bone length. In adult, hyperdivergent group had target amount of upper molar relative eruption than normal ones(p<0.01), but relative eruption of lower molar was similar to normal ones. 4. Hyperdivergent group had larger angle between lower occlusal plane and mandibular plane than normal group(p<0.01). Upper occlusal plane of adult groups rotated more antero-superiorly than child groups, and adult hyperdivergent group had sleeper upper occlusal plane than normal group(p<0.05).

• The korean journal of orthodontics
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• v.29 no.6 s.77
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• pp.707-720
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• 1999

The purpose of this study was to evaluate racial differences In head posture and the influence of head posture to the craniofacial morphology. The sample group of this study was made up of 51 Korean males and 120 Scandinavian Caucasian males. From the comparison of the cranio-cervical angle and the variables of craniofacial morphology between them, the following results were obtained. 1. The cranio-cervical angle (NSL/OPT) was on average 9.28 degrees larger In Koreans. 2. The length of the anterior cranial base (N-S) was on average 4.66mm shorter in Koreans. 3. The length of the maxillary base (sp-pm and ss-pm) were on average 2.75mm and 4.65mm shorter in Koreans respectively, the anterior maxillary height (n-sp) was on average 2.60mm longer, the posterior dimension (s-pm) was found to be 2.06mm longer in Koreans, and the maxillary inclination (NSL/NL) was identical in both samples. 4. The mandibular body length (pg-tgo) and ramus height (ar-tgo) were identical in the two groups, but the genial angle (ML/RL) was 3.22 degrees smaller and the mandibular plane inclination (NSL/ML) was 2.44 degrees larger in Koreans 5. The maxillary prognathism (s-n-sp and s-n-ss) and the mandibular prognathism (s-n-sm) were identical in both samples. 6. The sagittal jaw relationship (ss-n-pg) was 1.44 degrees larger in the Korean sample, but the vortical jaw relationship (NL/ML) was not significantly different. 7. The anterior facial height (n-gn) was 5.57mm longer in the Korean sample. 8. The mandibular alveolar prognathism (CL/ML) was 5.71 degrees greater and the interincisal angle (ILs/ILi) was 3.08 degrees more acute in Koreans. Taken together these results, craniofacial morphology can be influenced by the head posture defined by cranio-cervical angulation.

• Journal of Periodontal and Implant Science
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• v.36 no.1
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• pp.15-26
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• 2006

흡수성 차페막을 이용한 조직 유도 재생술시 차폐막의 견고성으로 미루어 보아 재생을 위한 공간의 유지가 어려울 수 있다. 조직 유도 재생술과 함께 골이식술을 시행함으로써 공간 확보와 함께 적절한 혈병의 유지를 도모할 수 있고 이식된 골은 선생골 형성을 위한 핵으로 작용할 수도 있다. 최근에 사람의 치아회분말과 연석고를 혼합한 골이식재가 여러 연구를 통해 좋은 골이식재로 평가되었다. 본 연구에서는 성견 하악 소구치 2급 치근이개부위에 외과적으로 형성하여 흡수성 차폐막과 치아회분말-연석고 혼합 이식재를 이용한 조직유도재생 술을 시행하여 치주 조직 재생의 양상을 조직학적으로 관찰하고자 한다. 생후 12개월에서 16개윌 된 체중 15 Kg 내외의 성견 4마리를 이용하였다. 실험 재료로 생체흡수성 차폐막 (Biogide(R), Swiss) 를 사용하였고, 골이식재로 치아회분말-연석고를 혼합매식 하였다. 양측 상악 소구치 부위에 변연 치조골하방에 4 mm ${\times}$ 4 mm ${\times}$ 4 mm, (깊이 ${\times}$ 근원심 ${\times}$ 협설폭경) 깊이로 골내낭을 형성하였다. 형성된 골내낭의 기저부위 치근 표면에 1/4 round bur로 notch를 형성하여 참고점으로 하였다. 무작위로 선택된 한 쪽의 결손부를 대조군으로 오직 생체 흡수성 차폐막을 사용하였고, 실험군으로 치아회분말-연석고와 생체 흡수성 차폐막을 결손부로부터 2 mm 이상 덮을 수 있도록 다듬어 결손부 위에 위치시킨 후 협측 판막을 덮고 봉합하였다. 4주 후 2마리 ,8주 후 2마리를 희생시키고 통상의 방법으로 고정, 탈회, 포매의 과정을 거쳐 광학 현미경으로 검경하였다. 그 결과, 1. 4주 대조군에서 Bio-gide(R)는 완전한 흡수를 보였고, 치근이개부내에는 큰 공간이 존재하였다. 2. 4주 실험군에서 역시 Bio-gide(R)는 완전한 흡수를 보였고, 골 결손부내에 더 많은 신생골 관찰되었다. 그러나 아직까진 기존골과 신생골간에 명확한 차이가 있어서 쉽게 구분할 수 있었다. 또한 골이식재 주변으로 파골세포가 다수 관찰되며 이로 미루어 보아 활발한 골흡수가 일어남을 알 수 있었다. 3. 8주 대조군에서 결손부내에서는 기존골에 인접하여 신생골 형성이 부분적으로 일어났으나 연조직 침입이 관찰되었다. 4. 8주 실험군은 신생골이 기존골과 매우 유사한 형태로 관찰되었고, 신생골 형성 부위에 신생 혈관 증식이 관찰되었다. 또한 골내낭 기저부위에서는 백악질과, 치주인대가 재생됨이 관찰되었다. 이상의 결과에서 치아회분말-연석고 혼합매식은 골재생을 위한 골전도성이 있는 재료로 사료되며, 이를 이용히여 치주조직재생술시 흡수성 차폐막과 병행하여 사용한다면 더 많은 골재생이 있을 것으로 기대된다.

• The korean journal of orthodontics
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• v.26 no.5 s.58
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• pp.469-485
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• 1996

Orthodontic patients are individuals that grow and develop ; therefore selection of the proper time for orthodontic treatment is considered to be one of most difficult and yet difficult factor. Since the development of cephalometric X-ray, amount and Pattern of craniofacial growth change with aging could be predicted and be came useful in the process of orthodontic treatment. The relationship between the mean values of cephalometric measurements and body height and weight was studied among the groups(boys and girls) of Korean children from the ages 6-years to 17-years. 409 boys and 437 girls with no abnormality in growth and development and no history of orthodontic treatment from the ages of 6 years to 17 years were chosen as subjects Cephaloment X-ray were taken for 3 years and hard tissue analysis based on Burstone's COGS, which was devided into measurements of 6 parts(Cranial base, Maxillar and Mandible, Dental measurements). The relationship between craniofacial growth and height & weight was studied. The following conclusions were obtained : 1. The maximum growth in the measurements of cranial base, N-Ar(FH), N-Ba(FH) corresponded with the age with the maximum increase in body height & weight in both boys and girls. 2. Genial angle gradually decreased with aging in both boys and girls. 3. N-ANS(L) showed greater amount of growth than ANS-Ne(L), and this had greater influence on facial profile. 4. N-A-$Pog^{\circ}$ decreased with aging, and mandibular growth exceeded maxillary growth in amount and rate. 5. Length of Y-axis Increased, but Y-axis to FH plane remained constant. This show that mandible grows at a constant angulation to cranial base. 6. As permanent teeth erupt, interincisal angle deceased.

• The korean journal of orthodontics
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• v.27 no.3 s.62
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• pp.421-430
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• 1997

Alveolar bone grows with development of tooth germs and roots; bone deposition occurs with tooth eruption. Bone components undergoes processes of resorption and deposition, and when the balance between them is disrupted, decrease in alveolar bone height or excessive bone deposition result. It has been hon that repositioning of teeth through orthodontic treatment can cause alveolar bone resorption which result in decreased alveolar bone height, and there have been many studies to evaluate such effects. X-ray films that could be replicated and standardized were chosen in clinical studies, and among them, bitewing films were used for objective evaluation of changes in alveolar bone level. Twenty subjects, 10 to 13-year- old (average 12.2) children with Cl I molar key, healthy oral condition, no congenital missing, no periodontal disease, and pre-and post-orthodontic bitewing films, were randomly selected for comparison of alveolar bone heights. Amounts of tooth and changes in alveolar bone heights were analyzed. The following results were obtained: 1. Amount of tooth movement in canine, premolar, and molar regions, changes in tooth axis, and changes in alveolar bone heights were measured, and the mean and median values were obtained. 2. When pre-and post-orthodontic alveolar bone levels were compared, larger changes were noticed in maxilla than mandible. 3. When mesio-distally compared, larger changes were observed in the distal sides of 3D3 and 4M3, mesial sides of 4M3 and 4D3, distal sides of 4D3 and 5M3, mesial sides of 5M3 and 5D3, md distal sides of 5D3 and 6M3. 4. When the amounts of tooth movements(TX, TY)and changes in tooth axis(A) were compared,34TX, 34TY, 34A of both sides in maxilla were greater, iud changes in alveolar bone level were greater than any other region.

• The korean journal of orthodontics
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• v.27 no.6 s.65
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• pp.963-978
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• 1997

Orthodontic patients are individuals that grow and develop ;therefore selection of the proper time for orthodontic treatment Is considered to be one of the most difficult and yet difficult factor.Since the development of cephalometric X-ray, amount and pattern of craniofacial growth change with aging could be predicted and became useful in the process of orthodontic treatment. The relationship between the mean values of cephalometric measurements and body height and weight was studied among the groups(boys and girls) of Korean children from the ages of 3-years to 12-years. 126 boys and 90 girls with no abnormality in growth and development and no history of orthodontic treatment from the ages of 3 years to 12 years were chosen as subjects: Cephalometric X-ray were taken for 2 years and hard tissue analysis based on Burstone's COGS, which was divided into measurements of 6 parts (Cranial base, Maxillar and Mandible, Vertical measurements, Horizontal measurements, Basal bone relationship, Dental measurements). The relationship between craniofacial growth and body height & weight was studied. The following conclusions were obtained : 1. The maximum growth in the measurements of cranial base, N-Ar(FH), N-Ba(FH) corresponded with the age with the maximum increasein body height & weight in both boys and girls. 2. Genial angle gradually decreased with aging in both boys and girls. 3. N-ANS(L) showed greater amount of growth than ANS-Me(L), and this had greater influence on facial profile. 4. $N-A-Pog^{\circ}$ decreased with aging, and mandibular growth exceeded maxillary growth in amount and rate. 5. Length of Y-axis increased, but Y-axis to FH plane remained constant. This show that mandible grows at a constant angulation to cranial base. 6. As Permanent teeth erupt, interincisal angle deceased.

• The korean journal of orthodontics
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• v.28 no.5 s.70
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• pp.855-864
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• 1998

The purposes of this study were to evaluate the cephalometric characteristics of Korean female patients with Class II division 2 malocclusion and to compare Korean females with Caucasian females who had same type of malocclusion. All of the samples had Class II division 2 malocclusion with deep overbite (more than 4mm) and full permanent dentition. These samples were divided into two groups according to the races: Group 1(N=16; Korean females; average age=18Y 2M) and Group 2 (N:20; Caucasian females; average age=14Y 2M). The pretreatment lateral cephalograms were measured, analyzed and compared by using 38 variables and independent t-test. And the results were as follows: 1. Although there were no differences in Overbite, SN to mandibular plane angle, Palatomandibular plane angle, and FMA between Group 1 and 2, the other vertical relation variables of maxilla and mandible (SN to palatal plane angle, SN to occlusal plane angle, ODI) of Group 1 showed more clockwise rotation tendency of occlusal plane and less hypodivergency tendency than those of Group 2. 2. There were no differences in mandibular body length and ramus height between Group 1 and 2 except small upper genial angle of Group 1. There was less counterclockwise rotation tendency of mandible in Group 1. 3. There were no statistical significant differences in UAFH/LAFH and PFH/AFH between Group 1 and 2. 4. Although there were no differences of overjet and anteroposterior position of mandible between Group 1 and 2, the position of maxilla of Group 1 was more retropositioned than that of Group 2. 5. Except the more protrusion of lower incisor to A-Pog of Group 1, there were no differences of inclination and distance of upper and lower incisors to basal plane between Group 1 and 2. 6. The distance from upper- first molar to palatal plane showed no difference between Group 1 and 2. But the distance from lower first molar to mandibular plane of Group 1 was greater than that of Group 2. So it may be partially related to the clockwise rotation of occlusal plane and the less counterclockwise rotation tendency of mandible of Group 1. 7. Group 1 had more protrusive upper and lower lips than Group 2.