• 대한치과교정학회지
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• 제9권1호
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• pp.85-98
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• 1979

This investigation was designed to compare the craniofacial and dental morphology of class III malocclusion with that of normal occlusin in children, and to determine the incidence of various class III craniofacial skeletal patterns. The material selected for this study consisted in standard lateral cephalograms of eighty two Korean children, forty one boys and forty one girls, aged 10 through 12 years, having class III malocclusion, and forty two Korean children, twenty boys and twenty two girls, with normal occlusion in the same age. Using the tracings of the standard lateral cephalograms, various angular and linear measurements were recorded, tabulated and statistically analyzed, and then the class III craniofacial skeletal morphology was divided into various patterns by the degree of SNA and SNB, which respectively were below, within or beyond the normal range of those of normal occlusion. The following characteristics of the craniofacial and dental morphology of class III malocclusion were observed. 1. The cranial base length of class III malocclusion was smaller than that of normal occlusion, and the small saddle angle was a characteristic figure of class III malocclucion. 2. Maxillary length of class III malocclusion was smaller than that of normal occlusion, and point A was retropositioned relative to cranial base but not PNS in class III malocclusion. Maxillary base inclination was not significantly different between the two, but occlusal plane to palatal plane was small in class III malocciusion. 3. The mandibular body length shown no difference between the two, but the mandibular body positioned anteriorly relative to cranial base in class III malocclusion. Ramus height, gonial angle, and mandibular effective length were large in class III malocclusion. Mandibular plane angle and joint angle had no difference between the two, and occlusal plane to mandibular plane angle was large in class III malocclusion. 4. Maxillary incisor inclination was not significantly different between class III malocclusion and normal occlusion, but mandibular incisors positioned and inclined lingually and consequently interincisal angle was large in class III malocclusion. 5. Class III malocclusion was divided into six categories of craniofacial skeletal pattern. The most common class III pattern was found to be one in which the maxilla was within the normal range of prognathism while the mandible extended beyond this range. The pattern in which the maxilla was below the normal range of prognathism while the mandible was within this range was approximately one fifth of the class III sample.

• Journal of Periodontal and Implant Science
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• 제45권5호
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• pp.162-168
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• 2015

Purpose: The aim of this study was to analyze the anatomical dimensions of the buccal bone walls of the aesthetic maxillary region for immediate implant placement, based upon cone-beam computed tomography (CBCT) scans in a sample of adult patients. Methods: Two calibrated examiners analyzed a sample of 50 CBCT scans, performing morphometric analyses of both incisors and canines on the left and right sides. Subsequently, in the sagittal view, a line was traced through the major axis of the selected tooth. Then, a second line (E) was traced from the buccal to the palatal wall at the level of the observed bone ridges. The heights of the buccal and palatal bone ridges were determined at the major axis of the tooth. The buccal bone thickness was measured across five lines. The first was at the level of line E. The second was at the most apical point of the tooth, and the other three lines were equidistant between the apical and the cervical lines, and parallel to them. Statistical analysis was performed with a significance level of $P{\leq}0.05$ for the bone thickness means and standard deviations per tooth and patient for the five lines at varying depths. Results: The means of the buccal wall thicknesses in the central incisors, lateral incisors and canines were $1.14{\pm}0.65mm$, $0.95{\pm}0.67mm$ and $1.15{\pm}0.68mm$, respectively. Additionally, only on the left side were significant differences in some measurements of buccal bone thickness observed according to age and gender. However, age and gender did not show significant differences in heights between the palatal and buccal plates. In a few cases, the buccal wall had a greater height than the palatal wall. Conclusions: Less than 10% of sites showed more than a 2-mm thickness of the buccal bone wall, with the exception of the central incisor region, wherein 14.4% of cases were ${\geq}2mm$.

• Restorative Dentistry and Endodontics
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• 제28권4호
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• pp.341-347
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• 2003

This study was conducted to evaluate the temperature rise on the root surface while the root canal is being obturated using continuous wave of condensation technique. Maxillary central incisor was prepared for repeated canal obturation. Ten thermocouples (Omega Engineering Inc., Stanford, USA) were placed at 1 mm increment from the anatomical root apex. The real temperature of Buchanan plugger was recorded before insertion into the root canal. The root canal was obturated with continuous wave of condensation technique as described by Buchanan and the root surface temperature was recorded during obturation at $150^{\circ}C,{\;}200^{\circ}C,{\;}250^{\circ}C{\;}and{\;}300^{\circ}C$ temperature settings of System B HeatSource (Model 1005, Analytic technologies, Redmond, WA, USA). After completion of the temperature recording, the dentinal-cementum thickness at each sites was measured. The data were analyzed using one-way ANOVA followed by Scheffe's test and linear regression test. The results were as follows. 1. When the temperature was set at $150^{\circ}C,{\;}200^{\circ}C,{\;}250^{\circ}C{\;}and{\;}300^{\circ}C$ on the digital display of System B HeatSource, the real temperature of the plugger at the 1mm point from the tip revealed $130.82{\pm}2.96^{\circ}C,{\;}158.00{\pm}5.26^{\circ}C,{\;}215.92{\pm}6.91^{\circ}C{\;}and{\;}249.88{\pm}3.65^{\circ}C$ respectively. 2. The position of 8 mm from the anatomical apex showed the highest temperature increase at each temperature settings and it was significantly higher than those of other positions (p<0.0l). The temperature rise was constantly increased toward coronal portion from apex of the root. 3. The maximum temperature increase on the root surface was $2.37{\pm}0.09^{\circ}C{\;}at{\;}150^{\circ}C{\;}setting,{\;}3.11{\pm}0.12^{\circ}C{\;}at{\;}200^{\circ}{\;}setting,{\;}3.93{\pm}0.09^{\circ}C{\;}at{\;}250^{\circ}C{\;}setting{\;}and{\;}5.69{\pm}0.15^{\circ}C{\;}at{\;}300^{\circ}C$ setting respectively. These results suggest that it be relatively kind to the supporting tissues of the root that the root canal is obturated using continuous wave of condensation technique at $150^{\circ}C,{\;}200^{\circ}C,{\;}250^{\circ}C{\;}and{\;}300^{\circ}C$ temperature settings on digital temperature display of System B HeatSource.

• 대한치과보철학회지
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• 제31권3호
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• pp.394-410
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• 1993

This study was accomplished for appreciation of the mandibular moments according to antero- posterior movement of pivot placed on the lower natural dentition. For this study, 20 subjects(male, $21\sim30$ yrs., average age 24) in the category of normal occlusion were selected, and the intraoral Vitallium clutches were cast and fabricated for each subjects. A 2-dimension PSD(Position Sensitive Detector, Hamamatsu Photonics Co., Japan) was attached to maxillary clutch in a mode of three dimensional control and LED (Light Emit Diode, Hamamatsu Photonics Co., Japan) was set up on mandibular clutch. Both clutches were set into oral cavity of each subjects and adjusted. Then the subjects were allowed to intercuspated with maximal bite force while the pivoting ball in the mid-line moving from anterior toward posterior position. The displacement scales were recorded by CCD camera(Sony, CCD-TR-705) and VCR, The conclusions were as follows : 1. When the subject was allowed to bite the metal pivoting ball in the midline of lower dentition with maximal bite force voluntarily while moving from lower central incisor to canine, 1st premolar, End premolar, 1st molar and 2nd molar. The lever actions on the pivot were revealed in all subjects. The equilibrium of moment were revealed on the pivots of 1st premolar(14 subjects), End premolar(4 subjects), and canine(2 subjects) areas. 2. The changes of loading on the TMJ according to antero-posterior positional changes of metal pivoting ball were able to recognize as follow. Compression on the TMJ was increased when the pivot moves anteriorly from the equilibrium point, and tension on the TMJ was increased when posteriorly. 3. 13 subjects were recognized their habitual chewing sides(Rights, Left8), and 7 subjects were not. During maximal biting, mandible was displaced toward their habitual chewing sides on the metal pivoting ball in the frontal plane. 4. In cephalometric analysis, the average genial angle of 20 subjects was $116.75^{\circ}$ and the average mandibular body length was 79.77mm. The equilibrium points of mandibular moment were positioned more posteriorly in the subjects having larger Genial angle than in the smaller(p<0.05). Relationships among the angle between FH plane and occlusal plane, the angle between occlusal plane and mandibular plane , and mandibular body length were not significant(p>0.05).

• 대한치과교정학회지
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• 제29권5호
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• pp.563-573
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• 1999

본 연구는 치아크기 측정시 버니어 캘리퍼스를 사용한 계측치와 석고모형을 촬영하여 컴퓨터를 사용한 계측치를 서로 비교함으로써 석고모형 분석시 컴퓨터 이용 가능성을 알아보고자 시행되었다. 치아밀집치열 특징을 지니며 모든 치아의 맹출이 완료된 상하악 20조의 석고 모형의 좌측 중절치부터 제 1대구치까지 12개의 치아를 대상으로 하여, 각 치아의 근원심폭경을 버니어 캘리퍼스와 컴퓨터를 이용하여 2주 간격으로 2회 측정하여 실험측정치를 얻은 다음, 측정에 이용된 석고모형을 근원심접촉점 부위에서 개개치아로 분리한 후, 마이크로미터를 이용하여 측정한 표준치와 비교분석하였다. 계측시 오차의 원인을 알아보기 위하여 상하악의 occlusogram을 얻어 각 치아의 접촉점 이탈유무 및 정도를 구하고, TARG (Torque Angulation Reference Guide)를 이용하여 각 치아의 근원심경사도를 계측한 결과 다음과 같은 결론을 얻었다. 1. 2회 측정에 대한 재현도 비교시 버니어 캘리퍼스를 사용한 경우 12 개 치아 중 3개의 치아에서 유의한 차이가 나타났으며 컴퓨터의 경우에는 1 개의 치아에서 차이가 나타났다. 2. 치아크기 계측의 정확도를 알아보기 위하여 표준치와 비교한 결과, 버니어 캘리퍼스를 사용한 경우 12개 중 3개의 치아에서 유의한 차이가 있었으며 컴퓨터의 경우에는 12 개 중 2 개의 치아에서 차이가 나타났다. 3. 버니어 캘리퍼스를 사용한 경우 상악 제 1 대구치는 표준치에 비해 크게, 하악 제 1 대구치는 표준치에 비해 작게 재는 경향을 보였으며 컴퓨터의 경우 상하 제 1 대구치 모두 표준치에 비해 크게 재는 경향을 보였다. 4. 버니어 캘리퍼스로 계측시에는 하악 제 1 대구치가 가장 큰 오차를 보였으며 치아별로 오차정도가 다양하게 나타난 반면, 컴퓨터의 경우 치아별 오차정도의 차이를 보이지 않았다. 5. 접촉점 이탈정도 및 치관의 근원심 경사도와 오차정도의 상관성을 살펴본 결과 버니어 캘리퍼스로 측정한 경우 유의한 상관관계를 보이지 않았으나 컴퓨터로 계측한 경우 약한 순상관관계를 보였다. 이상의 결과는 모형분석을 위한 치아크기 계측시 컴퓨터 이용이 가능함을 시사하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권4호
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• pp.350-359
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• 2005

Sagittal split ramus osteotomy(SSRO) has been commonly performed in the mandibular prognathism. The previous studies of the mandibular anatomy for SSRO have mostly been used in dry skull without consideration of age, sex or jaw relationship of patients. This study was performed to evaluate the location of mandibular canal and the anatomy of ramus, such as the location of mandibular lingula and the ramal bone marrow, which were associated with SSRO procedures, in the patients with mandibular prognathism and normal young adults by using computerized tomographs(CT) and 3D images. The young adults at their twenties, who were considered to complete their skeletal growth, and seen in the Department of Orthodontics and Oral and Maxillofacial Surgery in Chonnam National University Hospital between March 2000 and May 2003, were selected. This study was performed in 30 patients (15men, 15women) who were diagnosed as skeletal class I normal relationship, and another 30 patients (15men, 15women) who were diagnosed as skeletal class III relationship upon clinical examination and lateral cephalometric radiographs. The patients were divided into 2 groups : Class I group, the patients who had skeletal class Ⅰ normal relationship(n=30, 15men, 15women), and Class III group, the patients who had skeletal class III relationship(n=30, 15men, 15women). Facial CT was taken in all patients, and pure 3D mandibular model was constructed by V-works version 4.0. The occlusal plane was designed by three points, such as the mesiobuccal cusp of both mandibular 1st molar and the incisal edge of the right mandibular central incisor, and used as a reference plane. Distances between the tip of mandibular lingula and the occlusal plane, the sigmoid notch, the anterior and the posterior borders of ramus were measured. The height of ramal bone marrow from the occlusal plane and the distance between mid-point of mandibular canal and the buccal or lingual cortex of the mandible in the 1st and 2nd molars were measured by V-works version 4.0. Distance(Li-OP) between the occlusal plane and the tip of mandibular lingula of Class III Group was longer than that of Class I Group in men(p<0.01), but there was no significant difference in women between both groups. Distance(Li-SN) between the sigmoid notch and the tip of mandibular ligula of Class III group was longer than that of Class I Group in men(p<0.05), but there was no significant difference in women between both groups. Distance(Li-RA) between the anterior border of ramus and the tip of mandibular lingula of Class III Group was shorter than that of Class I Group in men and women(p<0.01). Distance(Li-RP) between the posterior border of ramus and the tip of mandibular lingula of Class III Group was slightly shorter than that of Class I Group in men(p<0.05), but there was no significant difference in women between both groups. Distance(RA-RP) between the anterior and the posterior borders of ramus of Class III Group was shorter than that of Class I Group in men and women(p<0.01). Longer the distance(SN-AN) between the sigmoid notch and the antegonial notch was, longer the vertical ramal length above occlusal plane, higher the location of mandibular lingula, and shorter the antero-posterior ramal length were observed(p<0.01). Height of ramal bone marrow of Class III Group was higher than that of Class I Group in men and women(p<0.01). Distance between mandibular canal and buccal cortex of Class III Group in 1st and 2nd lower molars was shorter than that of Class I Group in men and women (p<0.05 in 1st lower molar in men, p<0.01 in others). These results indicate that there are some anatomical differences between the normal occlusal patients and the mandibular prognathic patients, such as the anterior-posterior length of ramus, the height of ramal bone marrow, and the location of mandibular canal.

• 대한치과교정학회지
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• 제25권4호
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• pp.375-401
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• 1995

성장기 골격성 제III급 부정교합의 원인은 상악 열성장, 하악 과성장과 두 양상의 조합형태로 나뉠 수 있다. 이중 상악 열성장을 동반한 성장기 골격성 제III급 부정교합의 경우, 상악골 전방견인 장치의 사용이 추천되고 있는데, 이러한 장치의 치료효과는 상악골의 전하방 이동과 하악골의 후하방 회전으로 알려져 있다. 국내외 선학들에 의해 상악골 전방견인 장치의 치료효과에 대한 많은 동물실험과 임상실험 결과가 발표되었으나, 연조직 측모 변화에 대한 연구는 미비한 상태이고, 또한 치료를 받은 환자간의 치료효과에 대한 비교도 부족한 상태이다. 이에 저자는 상악골 열성장으로 인한 성장기 골격성 제III급 부정교합으로 진단받고, 상악골 전방견인 장치로 치료 받은 93명의 환자를 성별, 치료개시 나이별, 구개봉합 opening여부(구강내 장치), 안모성장 형태에 따라 분류하여, 각 유형에 따라 어떠한 경조직과 연조직 측모의 변화가 관찰되는지 여부와, Angle씨 제 I 급 부정교합의 정상군 20명과 상악골 전방견인 장치로 치료받은 환자 사이에 경조직과 연조직에 있어서 성장량과 치료량에 어떠한 관계가 있는지 비교하여 다음의 결론을 얻었다. 1. 상악골 전방견인 장치 사용시 골격적 계측항목과 치아와 연조직 계측항목에서 성장량보다 많은 치료에 의한 변화량을 관찰할 수 있었다. 2. 남녀별 치료개시 나이에 따른 상악골 전방이동량과 하악골의 후하방 회전량에는 유의차가 없었다. 3. R.P.E.에서 La-Li보다 유의성 있는 상악골(A point)의 전방이동을 보였으며, 상악 전치의 순측 돌출이 La-Li를 사용하였을때 보다 감소되었다. 4. 안모성장 형태에 따라서는 상악골 전방이동량에는 유의차가 없었으나, 하악골의 후하방 회전을 나타내는 계측치에서 counterclockwise군이 clockwise군보다 많은 변화를 나타냈다. 5. 상순과 하순의 후경변화는 하부 골조직과 상하악 치아의 위치변화와 높은 상관관계를 보였으며, 상순의 고경과 nasolabial angle이 증가하고, mentolabial angle이 감소되었다.

• 대한치과교정학회지
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• 제38권2호
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• pp.104-120
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• 2008

본 연구는 전진이부성형술을 동반한 하악지 시상분할골절단술을 시행한 하악 전돌증을 가진 환자에서 하안면부, 특히 이부의 경조직과 연조직의 변화를 예측하는 데 있어서, 전후관계와 수직적 계측치를 통하여, 경조직의 변화에 따른 연조직의 상대적 변화량에 대해 비교, 분석하여 한국인의 골격성 III급 부정교합자의 악교정 수술시 전진이부성형술이 연조직 외형에 미치는 영향을 알아보고자 시행하였다. 교정치료와 악교정수술을 시행한 골격성 III급 부정교 합자 40명을 전진이부성형술을 시행하지 않고 하악지 시상분할골절단술만 시행한 환자 20명(BSSO group, 남자 10 명, 여자 10명)과 하악지 시상분할골절단술과 동시에 전진이부성형술을 시행한 환자 20명(Genie group, 남자 10명, 여자10명)으로 분류하여 수술직전(T1)과 수술직후(T2), 수술 최소 6개월 후(T3)의 측모 두부 방사선계측사진을 채득하여 계측 항목의 변화량을 분석하였다. BSSO군에서는 수술후 경조직 B점, Pogonion, Menton에 대하여 연조직 B점, Pogonion, Menton이 각각 수평적으로 0.997, 0.965, 1.022의 변화율을 보였으며, Genie군에서는 각각 0.824, 0.602, 0.887의 수평적 변화율을 보여서, Genie 군에서 연조직 B점, 연조직 Pogonion의 연조직 두께의 감소량이 더 크게 나타났다. 경조직 Pogonion(Pg)의 악교정수술 전과 후의 수평적 변화에 따른 하순의 하방점(Li), 연조직 B점 (B')의 변화간의 상관관계계수는 BSSO군에서는 각각 0.833, 0.922인 반면에, Genie 군에서는 각각 0.775, 0.799로 BSSO군에 비해서 상관관계가 다소 작은 것으로 나타났다. 이상의 결과에서 하악지 시상분할골절단술을 시행하는 환자에서 전진이부성형술을 동반할 경우에는 골격의 변화에 대해서 연조직의 두께 변화가 다소 적게 나타나므로 수술시에 이를 고려하여 전진이부성형술을 시행하여야 할 것이다.