• The korean journal of orthodontics
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• v.11 no.2
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• pp.135-142
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• 1981

This study was performed to observe the gross reactions of surrounding maxillary sutures to the widening of midpalatal suture in the dog. Three healthy dog were chosen for the experiment. One animal was used as control, and two were used as experimental animals. Midpalatal suture was expanded total 7mm with screw for 10 days. The following results were obtained : 1. Midpalatal suture was expanded with the most width, in which anterior was be more expanded than the posterior, and shape was wedge form. 2. Interincisive suture was definitely expanded. 3. Internasal suture and interfrontal suture were slightly expanded. 4. Expansion of frontomaxillary suture, frontoparietal suture, frontonasal suture, zygomatico temporal suture, zygomatico frontal suture, zygomatico maxillary suture, occipito mastoid suture, occipito parietal suture, naso incisive suture, naso maxillary suture, and incisive maxillary suture were not observed.

• The korean journal of orthodontics
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• v.16 no.1
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• pp.145-154
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• 1986

The purpose of the present study was to investigate the coordination and correlation of growth pattern between craniomaxillary complex and mandible, and among the craniofacial region, body-weight and stature. 14 boys and 16 girls between 6 and 12 years of age were used in this study. The result were as follows; 1. Total increments and maximum increment in mandible is higher than in oraniomaxillary complex during given period and no significant sexual difference existed. 2. The annual growth of craniofacial region did not assume an aspect of constant growth, periodically. 3. Craniofacial growth pattern was interrelated with stature more than with body-weight. 4. The growth behavior of body-weight and stature coincided with the growth of craniofacial region or preceded it in time.

• The korean journal of orthodontics
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• v.21 no.1 s.33
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• pp.7-16
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• 1991

To estimate the possibility of the application of TiN ion-plating to the orthodontic appliance, colorimetric properties, and characteristics of ion-plated film as well as adhesive strength of TiN film to the substrate and mechanical properties of ion-plated orthodontic appliance were investigated. The obtained results were as follows: 1) TiN ion-plated film had the colorimetric properties which were the hue of about 2.5 Y, the brightness of about 6, and the chroma of about 4 by the standard color chip of JIS. 2) TiN ion-plated film was $2{\mu}m$ in thickness and its deposition pattern was rather irregular. 3) TiN phase was confirmed on the X-ray diffraction pattern. 4) Critical load for delamination of ion-plated film from stainless steel band was 10N. 5) Tensile and yield strength of ion-plated specimen was increased about 10Kg $f/mm^2$, while elongation was decreased $1\%$ compairing to the values of the non ion-plated specimen.

• The Journal of the Korean dental association
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• v.19 no.2 s.141
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• pp.167-174
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• 1981

The purpose of this study was observing the annual growth increment in cephalogram. The cephalograms of 29 boys & 23 girls were analized by method of Downs & Steiner, range from 7 to 8 years in Korean children. the results were as follows; 1. The craniofacial complex of Korean children grew downward and fordward. 2. The pronounced linear and angular growth changes were in the upper central incisors and lower central incisors. 3. The SN Plane to Mandibular plane angle was reduced. 4. The SNA and SNB was almost constant in male.

• The Journal of the Korean dental association
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• v.19 no.2 s.141
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• pp.181-185
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• 1981

In this study an attempt has been made to throw some light on the problem of the mandibular third molar on measurement made from 302 orthopantomograms of patients at the age of 8 to 20 years. The following conclusions were drawn on the basis of the present study. 1. The amount of growth from the lower first molar to the anterior border of the ramus from 8 years to 14 years was 7.9mm in the male and 7.5mm in the female. The growth from 15years 20 years was 4.5mm in the male and 2.6mm in the female. 2. The growth from the lower first molar to the posterior border of the ramus from 8 years to 14 years was 10mm in the male and 9.8mm in the female. The growth occurred after that was 5.8mm in the male and 2.0mm in the female. 3. The difference between A and C measurements for the various age groups remained fairly constant in the male and female.

• The Journal of the Korean dental association
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• v.22 no.12 s.187
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• pp.1067-1073
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• 1984

In the treatment of functional orthodontic problems, timing is not an issue. All orthodontists start as soon as the condition is recognized. However, there is an active dialogue concerning treatment timing for structure problems. The major points in contention center around the operator's ability is to control the growth of the facial bones and to maintain post-treatment tooth position through the maturation period (especially when this position was gained by techniques involving arch expansion or distal driving of posterior segments). Factors taken into account to determine the best time of orthodontic treatment include diagnosis, interception, growth rate, patient cooperation, eruptive state and treatment period. With those exceptions of all functional problems, mild dental discrepancies and skeletal deficiencies with a predictably excellent growth potential (early treatment), the period immediately following the eruption of the permanent second molars is the period during which most orthodontic treatment should be initiated. At this time the full volume of tooth substances is present, the individual growth pattern in well established, there are sufficient teeth to receive nearly any type of appliances and the patient can easily tolerate the wearing of appliances.

• The Journal of the Korean dental association
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• v.38 no.10 s.377
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• pp.962-968
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• 2000

치조골과 백악질이 치근막에 의하여 경계되어지지 않고 직접 접촉된 상태인 골유착치는 치조골성장장애, 불안전 맹출, 대합치의 정출, 인접치와의 불안정한 관계 등 다양한 문제를 야기한다. 골유착치의 진단은 방사선 사진에서 치근막의 소실, 타진시의 독특한 소리, periotest를 이용한 동요도 검사 등 다양한 방법이 사용되나 그 신뢰성은 높지 않은 편이다. 따라서 저자는 통산적인 방법은 견인을 시행한 후 견인여부를 평가하여 골유착 여부를 판단하는 임상적 진단법을 사용하고 있다. 골유착치의 치료는 subluxation & extrusion법, autotransplantation법, corticotomy법, segmental osteotomy법, ostectomy법등 다양한 방법이 제시되고 있다. Subluxation & extrusion법은 적용이 간편한 장점이 있으나 골유착의 재발로 인한 교정치료의 실패가능성이 높은 단점이 있다. 본 증례는 다수치의 부분맹출 및 골유착으로 인한 구치부 개방교합이 주소인 환자로 소구치는 통산적인 교정치료법으로 골유착된 대구치는 subluxation & extrusion법을 적용하여 양호한 치료 결과를 얻을 수 있었다.

• The Journal of the Korean dental association
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• v.54 no.7
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• pp.542-550
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• 2016

Recent technological advance have greatly expanded the application of invisible orthodontic treatment using clear thermoplastic materials. However, the final outcomes using clear aligner system do not achieve the level of final goal frequently, which results in case refinement, midcourse correction, or fixed orthodontic treatment. Therefore, mechanical properties of thermoplastic materials should be considered to improve the quality of outcomes. The purposes of this special article were to evaluate the force and stress depending on the materials, deflection and thickness of thermoplastic materials and to evaluate the mechanical properties of thermoplastic materials after repeated loading. Thickness and amount of deflection rather than products and materials showed the largest effect on force and stress. In all products, at least 159 gf of force was required for more than 1.0 mm deflection or when materials with 1.0 mm thickness were deflected. Orthodontic forces delivered by thermoplastic materials depend on the materials, thickness, amount of activation, and intra-oral condition. Proper thickness of thermoplastic materials and deflection level of tooth movement should be decided for the efficient and physiologic tooth movement.

• Journal of Technologic Dentistry
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• v.5 no.1
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• pp.31-34
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• 1983

We were usually make use of Viggo activator for orthodontic the state prognathous. But, it inconvenient for use because demend of long time until orthodontic use finished for restoration of everybody production and function(esthetic, mastication, phonetic). So, we were enough effect obtained for everybody function with this improve. 1. Improves Viggo activator inconvenience of insertion and remove. 2. It can be set with considering of functional and esthetics. 3. Get a orthodontics effect without lonf period. 4. Have no convenience to mastication at setting with occlusal correction at anytime.

• The korean journal of orthodontics
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• v.13 no.1
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• pp.83-94
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• 1983

For the better orthodontic diagnosis, case analysis, and treatment plan, the author studied the cephalometric analysis of 365 Korean with normal occlusion occording to the Steiner and Tweed analysis. The subjects consisted of 162 males and 203 females from 7 to 19 years with normal occlusion and were divided into three groups according to the Hellman's dental age. The results were obtained as follows: 1. The Ideal Acceptable Compromises were determined after measurement of male and female average by the Steiner analysis in Hellman's dental age III B, IV A, IV C group. 2. The Holdaway ration were 6.5:1.0 in Group I, 6.5:1.5 in Group II, 6.5:1.5 in Group III. 3. The Tweed's triangle were $FMA\;27^{\circ}\;FMIA\;58^{\circ}\;IMPA\;95^{\circ}$ in Group I and II, $FMA\;27^{\circ}\;FMIA\;62^{\circ}\;IMPA\;95^{\circ}$ in Group III.