• Journal of Chest Surgery
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• 제28권5호
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• pp.443-446
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• 1995

The present study was designed to determine whether cyclosporine A inhibits Major Histocompatibility Complex Class II antigen[MHC II expression in the allograft rat heart myocardium. In this rat allograft study we also tried to elucidate whether CSA inhibits MHC II in a dose dependent way. Hearts were isolated from LBN rats weighing 200-250 grams and heterotopically transplantated into the abdomen of weight-matched ACI rats. The ACI rats were randomly assigned to one of the three experimental groups according to cyclosporine dosage: {1}control [no CSA , n=6 {2}CSA 5 mg/day , n=5 {3}CSA 10 mg/day, n=5. The transplanted hearts were harvested 5 days postoperatively and analyzed. MHC II expression was detected by indirect immunoperoxidase staining and quantified via computer image analysis system. The % positive area reading was obtained in each slide [50 areas per group and compared to other groups. Significant differences were noted between three groups [p<0.05 . We conclude that CSA inhibits MHC II in heterotopically transplanted allograft rat heart in a dose dependent way.

• 대한치과교정학회지
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• 제19권1호
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• pp.201-218
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• 1989

This study was focused on the distribution of different facial types of the Class II division I malocclusion groups and skeletal characteristics of the each group and those that anteropsterior relationship of the maxilla and mandible calculated from the analysis of ANB angle and Wits appraisal was quite different from each other, as well. Cephalometric headplates of 140 persons of Class II division 1 malocclusion whose mean age was 11.2 years and 69 persons of normal occlusion whose mean age was 12.2 years were utilize as materials. Measurements were recorded, tabulated and statistically analyzed employing the tracings of the lateral cephalograms, then Class II division 1 malocclusion group was divided into 9 Types according to the angle of SNA and SNB for the anteroposterior relationship of the maxilla and mandible, another 9 Types according to the FH-NPog and SN-MP for the horisontal and vertical relationship, and the other 9 Types according to the ANB and Wits appraisal for intermaxillary relationship as well, with which was based on $Mean{\pm}$ 1SD of those of normal occlusion. The result allowed the following conclusion: 1. $37.1\%$ of population demonstrated maxilla within nounal range and retrognathic mandible to the cranial base, $30\%$ for both maxilla and mandible within normal range, $20\%$ for retrognathic maxilla and mandible and $12.9\%$ of the rest were ananged in Class II division 1 maloccusion groups. 2. Retrognathic mandible and hyperdivergent face accounted for $30.7\%$, mesognathic mandible and neutrodivergent face for $29.3\%$, mesognathic mandible and hyperdivergent face for $16.4\%$, retrognathic mandible and neutrodivergent face for $13.6\%$, mesognathic mandible and hypodivergent face for $10\%$ of population were computed in Class II division 1 malocclusion groups. 3. It was suggested that skeletal Class II malocclusion might be due to anomaly in size and shape of cranial base, underdevelopment of mandible, retropositioning of mandible, underdevelopment of posterior face against anterior face, or any combination of these factors. 4. Population with underdevelopment and / or retropositioning of the mandible showed hyperdivergent tendency of facia profile. 5. The ANB angle and Wits appraisal did not coincide the severity of anteroposterior dysplasia in $35.7\%$ of Class II division 1 malocclusion group each other, and this inconsistency was suggested to be related with mandibular rotation, inclination of cranial base, and anteroposterior position of the maxilla.

• 대한치과교정학회지
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• 제54권3호
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• pp.171-184
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• 2024

Objective: This study aimed to determine the maxillary and mandibular basal bone regions and explore the three-dimensional positional relationship between the dentition and basal bone regions in patients with skeletal Class I and Class II malocclusions with mandibular retrusion. Methods: Eighty patients (40 each with Class I and Class II malocclusion) were enrolled. Maxillary and mandibular basal bone regions were determined using cone-beam computed tomography images. To measure the relationship between the dentition and basal bone region, the root position and root inclination were calculated using the coordinates of specific fixed points by a computer program written in Python. Results: In the Class II group, the mandibular anterior teeth inclined more labially (P < 0.05), with their apices positioned closer to the external boundary. The apex of the maxillary anterior root was positioned closer to the external boundary in both groups. Considering the molar region, the maxillary first molars tended to be more lingually inclined in females (P = 0.037), whereas the mandibular first molars were significantly more labially inclined in the Class II group (P < 0.05). Conclusions: Mandibular anterior teeth in Class II malocclusion exhibit a compensatory labial inclination trend with the crown and apex relative to the basal bone region when mandibular retrusion occurs. Moreover, as the root apices of the maxillary anterior teeth are much closer to the labial side in Class I and Class II malocclusion, the range of movement at the root apex should be limited to avoid extensive labial movement.

• 대한치과교정학회지
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• 제50권3호
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• pp.170-180
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• 2020

Objective: To compare short- and long-term dentoalveolar, skeletal, and rotational changes evaluated by Björk's structural method of superimposition between children with Class II malocclusion treated by functional appliances and untreated matched controls. Methods: Seventy-nine prepubertal or pubertal children (mean age, 11.57 ± 1.40 years) with Class II malocclusion were included. Thirty-four children were treated using an activator with a high-pull headgear (Z-activator), while 28 were treated using an activator without a headgear (E-activator). Seventeen untreated children were included as controls. Lateral cephalograms were obtained before treatment (T1), after functional appliance treatment (T2), and after retention in the postpubertal phase (T3). Changes from T1 to T2 and T1 to T3 were compared between the treated groups and control group using multiple linear regression analysis. Results: Relative to the findings in the control group at T2, the sagittal jaw relationship (subspinale-nasion-pogonion, p < 0.001), maxillary prognathism (sella-nasion-subspinale, p < 0.05), and condylar growth (p < 0.001) exhibited significant improvements in the Z- and E-activator groups, which also showed a significantly increased maxillary incisor retraction (p < 0.001) and decreased overjet (p < 0.001). Only the E-activator group exhibited significant backward rotation of the maxilla at T2 (p < 0.01). The improvements in the sagittal jaw relationship (p < 0.01) and dental relationship (p < 0.001) remained significant at T3. Condylar growth and jaw rotations were not significant at T3. Conclusions: Functional appliance treatment in children with Class II malocclusion can significantly improve the sagittal jaw relationship and dental relationships in the long term.

• Restorative Dentistry and Endodontics
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• 제26권6호
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• pp.492-498
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• 2001

The purpose of this study was to evaluate four different composite resins in vitro for microleakage in Class II box type restorations that have gingival margins apical to the cementoenamel junction. Forty caries free extracted human molars were used in this study. The Class II cavities were prepared 1.0mm below cementoenamel junction with a #701 carbide bur. The teeth were randomly divided into four groups, each group comprising 20 treated cavities according to adhesives and filling materials ; Group 1: Scotchbond Multipurpose/Z 100. Group 2: Ariston Liner/Ariston pHc, Group 3: One Step/Pyramid, Group 4: Prime & Bond NT/SureFil. To simulate the clinical situation during restoration placement, a restoration template was fabricated and composite resin was filled using a three sited light-curing incremental technique. The specimens were stored in the 100% humidity for 7 days prior to thermocycling. The specimens were immersed in 2% methylene blue dye solution for 24 hours and then embeded in transparent acrylic resin and sectioned mesiodistally with a diamond wheel saw. The degree of marginal leakage was scored under the stereomicroscope($\times$20) and the data were analyzed by Kruskal Wallis test and Mann Whitney test. (omitted)

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.288-295
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• 1998

The microleakage of direct-access Class 2 restorations was evaluated. Cavities were prepared at mesial and distal proximal enamel surfaces of 20 extracted human molars through buccal window. Prepared cavities were filled with Ketac-Fil, Ketac-Silver, and Fuji II LC, following manufacturer's instructions. 4 specimens of each restorations were made through sectioning 1/4 of bucco-lingual length mesio-distally after thermocycling between $5^{\circ}C$ and $60^{\circ}C$ and imerging 0.5% basic-fuchsin dye solution. Leakage at both occlusal and gingival margin of each specimen was scored 0 to 3 with stereomicroscope. The results were as follows: 1. At occlusal margin, leakage in Ketac-Fil group was more than Ketac-Silver and Fuji II LC group (ANOVA p<0.05) and there was no significant difference between Ketac-Silver and Fuji II LC group(p>0.05), and at gingival margin, there was no significant difference amang materials (p>0.05). 2. Occlusal margin leaked more than gingival margin in Ketac-Silver and Fuji II LC group (t-test p<0.05). 3. Leakage was different according to bucco-lingual location in Ketac-Fil and Fuji II LC group, and lingaul specimen exhibited more leakage(ANOVA p<0.05).

• 구강회복응용과학지
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• 제30권2호
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• pp.145-151
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• 2014

목적: 본 연구는 두가지 다른 방법에 의한 레진강화형 글래스 아이오노머(RMGI) 이장재의 적용이 2급와동 복합레진수복의 미세누출에 미치는 영향을 조사하고자 하였다. 연구 재료 및 방법: 36개의 발치한 치아에 2급 와동을 형성한 뒤 무작위로 3개의 군으로 나누었다. 1군은 대조군으로 이장재를 적용하지 않았으며, 2군은 치과용 탐침으로 RMGI 이장재 적용, 3군은 특별히 고안된 버로 RMGI 이장재를 적용한 뒤 복합레진은 똑같이 통상적인 방법으로 적층수복하였다. 2% 메틸렌 블루 염색한 뒤 치아장축과 평행하게 순설 방향으로 절단하여 미세누출을 현미경과 컴퓨터 프로그램을 사용하여 분석을 하였다. 데이터는 Kruskal-Wallis test와 Mann-Whitney U-test (P < 0.05)로 분석하였다. 결과: RMGI 이장재가 적용된 군은 그렇지 않은 군보다 월등히 적은 미세누출을 보였으며, 특히 특수 고안된 버를 사용한 군의 50%에서는 전혀 미세누출을 보이지 않았다. 그러나, 2군과 3군의 결과에서 통계적으로 유의한 차이는 관찰되지 않았다. 결론: 2급와동의 복합레진 수복에서 RMGI 이장재는 그 적용 방법에 관계없이 미세누출을 감소시키는데 효과적인 재료이다.

• 대한치과교정학회지
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• 제52권5호
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• pp.324-333
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• 2022

Objective: The aim of this study was 1) to investigate the prevalence and pattern of dental anomalies (DAs), 2) to compare DAs according to the type of malocclusion, and 3) to investigate the correlation between tooth impaction and other DAs in the Korean orthodontic population. Methods: A total of 3,240 orthodontic patients were classified as Class I, Class II, or Class III malocclusion groups. The presence and location of common DAs, including impaction, microdontia, agenesis, supernumerary tooth, transposition, and fusion, were identified by examining diagnostic records. Furthermore, samples were classified as Group 1 without impaction or Group 2 with impaction. The prevalence of other DAs concurrent with impaction was investigated and compared to Group 1. Results: Impaction was the most prevalent DA, followed by microdontia, agenesis, and supernumerary. Class I and Class III groups showed the same order of prevalence, but agenesis was more frequent than microdontia in the Class II group. The prevalence of the four DAs was lowest in the Class III group. Overall, 8.6% of patients were classified into Group 2. The incidence of DAs other than impaction and the prevalence of multiple concurrent DAs were significantly higher in Group 2. Impaction showed a significant relationship with supernumerary tooth, transposition, and fusion. Conclusions: The prevalence and pattern of DAs varied depending on the type of malocclusion. As there was a higher risk of other DAs in patients with impacted teeth, early detection of the impacted tooth and a detailed diagnosis of other possible DAs may be essential.

• 대한치과교정학회지
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• 제26권1호
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• pp.95-104
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• 1996

본 연구의 목적은 T-Scan system과 근전도를 이용하여 정상교합자와 과개교합자의 최대교합력과 근활성도간의 상관관계를 조사하기 위함이다. 연구대상은 두 집단으로 구성 되었다. 한 집단은 20명의 정상교합자이고 다른 집단은 30명의 과개교합자이다. 과개교합자는 Class I deepbite(9명의 남자와 7명의 여자)와 Class II div. 1 deepbite(8명의 남자와 6명의 여자)로 구성되었다. 이 연구로부터 얻어진 결과는 다음과 같다. 1. 최대교합력은 정상교합군에서 155.93 N, I급 과개교합군에서 165.11 N, II 1류 과개교합군에선 111.55 N이었으며, II급 1류 과개교합군의 최대교합력은 정상교합군에 비해 유의성 있게 낮았다(P<0.01). 2. 정상교합군과 과개교합군 모두에서 치야접촉점이 증가할수록 교합력은 증가하였다(표 3). 3. 최대교합시 II급 1류 과개교합군의 교근 및 전측두근의 근활성도는 전상교합군에 비해 현저히 낮았고(P<0.01),모든 군에서 교근의 활성도가 전측두근보다 높았다(P<0.05). 4. 모든 군에서 교합력과 근활성도, 치아접촉점의 수와 근활성도는 높은 상관관계를 보였다(표 5).

• 대한치과교정학회지
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• 제40권5호
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• pp.314-324
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• 2010

본 연구는 성인 환자를 대상으로 안면골의 수평적, 수직적 골격 형태에 따른 하악 전치부 치조골의 순설측 두께를 하악 전치 치축을 기준으로 계측하고, 하악 이부 치조골의 단면적을 비교해 형태학적 차이를 확인해 보기 위하여 시행되었다. 20세 이상 성인 환자들의 초진 시 측모두부 방사선 사진을 사용하여, 수평적, 수직적 분류 기준에 따라 9군으로 분류하여 무작위로 30명(남자 15명, 여자 15명)씩, 총 270명을 추출하였다. 수평적 골격 형태를 판단하는 기준으로 ANB 각도가 사용되었으며, 수직적 골격 형태를 판단하는 기준으로는 하악평면각(SN-MP 각도)을 사용하였다. 측모두부 방사선 사진에서 하악 전치부 치조골의 협설측 두께와 하악 이부 치조골의 단면적을 계측하여 형태학적 차이를 확인해 보았다. 연구 결과로 high angle group은 low angle group과 average group에 비해 CEJ 하방 2 mm 부위 아래의 협설측 치조골과 모든 부위의 설측 치조골에서 통계적으로 유의하게 얇은 두께를 보였으며 ($p$ < 0.05), low angle group과 average group 중에서 Class I, II group은 모든 부위에서 Class I average group에 비해 유사하거나 통계적으로 유의하게 두꺼운 치조골 두께를 보였다 ($p$ < 0.05). Average group 내에서 Class III group은 Class I, II group에 비해 치근 중간 부위의 협설측과 설측에서 통계적으로 유의하게 얇은 치조골 두께를 보였으며 ($p$ < 0.05), high angle group 중에서도 특히 Class III인 high angle group에서 더 얇은 평균 치조골 두께를 보였다. 수직적 안면 골격 형태에 따라 하악 이부 치조골의 단면적은 통계적으로 유의한 차이를 보이지 않았다 ($p$ > 0.05). 이상의 결과에서 성인의 교정 치료 시 Class III이면서도 high angle을 보이는 환자에서는 하악 전치부에서 얇은 치조골 두께를 가지게 되는 경우가 많으므로, 하악 전치의 위치를 결정할 때 주의를 기울여야 할 것으로 생각한다.