• Imaging Science in Dentistry
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• 제33권2호
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• pp.79-83
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• 2003

Purpose : To assess the relationship between the direction of the indicating rod of the radiographic stent for ideal prosthetic design and the actual possible path of implant fixture placement when residual ridge resorption is considered. Materials and Methods: The study materials consisted of 326 implant sites (male 214 cases and female 112 cases) from a total of 106 patients (male 65 patients and female 41 patients) who desired implant prostheses. Computed tomography of patients were taken and reformatted using ToothPix/sup (R)/ software. Bony defects, bony sclerosis, the change of the direction of indicating rod, and root proximity of the adjacent teeth were examined on the CT-derived images. Results: The rate of the irregular crestal cortex was relatively high on premolar and molar area of maxilla. Mandibular molar area showed relatively high rate of focal sclerosis on the area of implant fixture insertion. The position of the indicating rods were relatively acceptable on the molar areas of both jaws. However, the position of the indicating rods should be shifted to buccal side with lingual rotation of the apical end on maxillary anterior teeth and premolar area. Conclusion: Clinically determined rod direction and position of the indicating rod for implant placement was not always acceptable for insertion according to the reformatted CT images. The pre-operative treatment plan for implant should be determined carefully, considering the state of the alveolar bone using the reformatted CT images.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권4호
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• pp.272-277
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• 2011

Purpose: The aim of this study was to compare the estimated blood loss and determine the change in hemoglobin depending on the combination of each orthognathic surgery. Subjects and Methods: The subjects of this study were patients who underwent orthognathic surgery among those diagnosed with a dentofaical deformity in Mok-Dong hospital, Ewha Womans University from 2002 to 2009. One hundred patients (men - 36, women - 64, mean age of $24.5{\pm}4.6$) participated in the study and were divided into four groups (group 1 - bilateral sagittal ramus osteotomy [BSSRO], group 2 - BSSRO+Genioplasty, group 3 - Lefort 1+BSSRO+genioplasty, group 4 - anterior segmental osteotomy on maxilla and mandible). A comparative study on the estimated blood loss (EBL), operation time, peri-operative changes in hemoglobin was performed using anesthesia records. The results were analyzed statistically using a Mann-Whitney U-test and Spearman's Rho test - SPSS 12.0 (SPSS Inc. Chicago, IL, USA). Results: In group 1 (BSSRO), the mean EBL, operation time and change in hemoglobin was $394.43{\pm}52.69$ ml, $184{\pm}42.33$ minutes, and 1.43, respectively, In group 2 (BSSRO+genioplasty), it was $556.32{\pm}63.42$ ml, $231{\pm}37.45$ minutes, and 1.80, respectively. In group 3 (Lefort 1+BSSRO+Genioplasty), it was $820.55{\pm}105.54$ ml, $320{\pm}15.41$ minutes, and 2.73, respectively. In group 4 (segmental osteotomy), it was $1025.39{\pm}160.21$ ml, $355{\pm}20.10$ minutes, and 3.33, respectively. In particular, in group 3, significant differences were observed depending on the method of the orthognathic surgery. The mean EBL in a Lefort 1 osteotomy with advancement was only 687 ml, whereas Lefort 1 osteotomy with canting correction (992 ml), even impaction (764 ml), and posterior nasal spine impaction (100 ml) showed a much higher EBL. Conclusion: From these results, the EBL and peri-operation hemoglobin increased as treatment plans became more complicated and increasing operation time. Safe orthognathic surgery should be performed by applying proper autologous transfusion plans based on the average EBL of each orthognathic surgery type.

• Journal of Periodontal and Implant Science
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• 제31권3호
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• pp.565-571
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• 2001

The purpose of this study is to determine if a relationship exists among osteoporosis, alveolar bone density and periodontal disease in postmenopausal osteoporotic women and postmenopausal healthy women. Twenty-two women were evaluated for this study. They were attending the postmenopausal clinic, Seoul National University Hospital and generally healthy except osteoporosis. They had experienced menopause not less than one year when we began to examine them. Bone densities of lumbar area(L2-L4) was determined by DEXA(LUNAR-expert Co,. U.S.A). We diagnosed osteoporosis when T-score was below -2.5 and healthy state when T-score was over -1. Osteoporotic(10 female), not hormone-treated group and healthy control group(12 female) were asked for their age, menopausal age, menopausal period and the number of remaining teeth and examined clinically for plaque index(PI), gingival index(GI), clinical attachment loss(CAL) on their 6 Ramfjord index teeth. Intraoral radiographs were taken in maxillary anterior zone. All films were equally exposed and developed. Each films was digitized and analysed using image processing software, Scion image. Alveolar bone regions of interest were selected and Intensity of each pixel was quantized in the array ranging from 0(white) to 255(black). The two groups were comparable with respect age, menopausal age, menopausal period and number of remaining teeth. The osteoporotic women had significantly lower alveolar bone density than controls in maxilla. But no significant difference was found with respect clinical attachment loss, plaque index and gingival index. Supported by the Ministry of Public Health and Welfare, Korea (HMP-00-CH-10-0009).

• Journal of Periodontal and Implant Science
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• 제36권1호
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• pp.147-154
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• 2006

Surgical intervention in the posterior maxillary region requires detailed knowledge of maxillary sinus anatomy and the possible anatomical variations. This study evaluated the incidence, location of maxillary sinus septa by using radiographic (panoramic radiography and computed tomography) findings and comparison of panoramic radography with CT in antral anatomical variation. This study was based on data from 70 sinuses in partial dentate maxilla. The sample consisted of 61 patients(25 women and 36 men, with ages ranging between 19 and 77 years and a mean age of $49.4{\pm}11.3$ years) who were being treatment-planned to receive implant-supported restorations. First, the panoramic images were examined for the presence of antral septa by radiologist and examiner who don't know about CT findings. And incidence of antral septa was evaluated using an axial plane of CT image. The incidence of septa was compared between panoramic radiography and CT. The accuracy of the incidence was compared between radiologists and dentists. A total of 20 septa were found in 70 sinuses on CT image and the prevalence of one or more septa per sinus was found to be 28.6%. The assumed incidence of septa on panoramic radiography was $27.6%{\pm}2.2%$ in radiologist and $31.9%{\pm}5.8%$ in dentists. Erroneous diagnosis rate was 11.42% in radiologist and 15.96% in dentists. 40% of antral septa were located in the anterior(premolar) region, 30% of septa were located in the middle(first molar) and posterior(second molar) region separately. Prior to implant placement, it seems appropriate to consider panoramic radiography as a standard radiographic examination and periapical radiographs may be used to complete the findings in regions not sharply depicted in the panoramic radiograph. And cross-sectional imaging should be used in sites with severe bone loss and close proximity of the maxillary sinus.

• 대한치과교정학회지
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• 제34권5호
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• pp.380-393
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• 2004

본 연구의 목적은 정상교합자에서 전후방적 악골 관계에 따라 치아치조부 보상이 나타나는 양상을 알아보고 교정치료에 사용되는 여러 계측 항목에서 이들이 반영되는 정도를 분석하기 위한 것이다 악골 관계에 대한 치아치조성 보상을 분석하기 위하여 정상 교합자 90명(남자 50명, 여자 40명)의 측모 두부 X-선 사진을 계측하여 전후방적 악골 관계에 따라 각각 세 군으로 분류하였다. 6개의 골격 계측 항목과 19개의 치아 계측 항목에 대해 independent t-test, 상관분석과 회귀분석을 실시한 결과, 다음과 같은 결론을 얻었다. 악골 관계에 대한 치아치조부 보상으로 하악골이 상악골에 비해 전방 위치할수록 상악 전치는 순측 경사되고 하악 전치는 설측 경사되며 교합 평면은 경사가 완만해졌다. 치아 계측 항목 중 L1 to SN과 L1 to FH에서 전후방적 악골 관계에 대한 보상적 변화가 가장 유의성 있게 나타나 상악 전치보다 하악 전치가 치아치조부 보상과 더 관련이 있었다. 치아 계측 항목 중 U1 to PtGu과 L1 to APog은 전후방적 악골 관계와 무관하게 거의 일정한 값을 보였다.

• 치과방사선
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• 제28권1호
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• pp.27-36
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• 1998

The purpose of this study was to obtain information on the clinical and radiographic features of the fibro-osseous lesions in the jaws. For this study, the author examined and analysed the clinical records and radiographs of 71 cases of 68 patients in fibrous dysplasia, 35 cases of ossifying fibroma and 30 cases of 16 patients of periapical cemental dysplasia diagnosed by clinical and radiographic or histopathological examinations. The obtained results were as followings: L Fibrous dysplasia occurred most frequently in the 2nd decade (30.0％), ossifying fibroma in the 3rd-4th decades, periapical cemental dysplasia in the 4th decade, and all of three lesions showed slight predilection in females. In most cases, chief complaints were painless facial swelling in fibrous dysplasia and ossifying fibroma, and periapical cemental dysplasia was found accidentally in radiographs. 2. Fibrous dysplasia was occurred more frequently in maxilla, ossifying fibroma in mandible and both lesions in premolar-molar area. Periapical cemental dysplasia was occurred most frequently in the mandibular anterior area. The size of fibrous dysplasia was larger than that of ossifying fibroma, and the shape of ossifying fibroma was more round and elliptical than fibrous dysplasia whose was fusiform. 3. Fibrous dysplasia was shown homogeneous radiopaque shadow of 57.6％ and ossifying fibroma & periapical cemental dysplasia were shown mixed appearance of radiolucency and radiopacity shadows at 74.2％, 60.0％, respectively. 4. Fibrous dysplasia was entirely shown poorly defined at 87.7％, but ossifying fibroma & periapical cemental dysplasia were shown well outlined at 60.0％, 70.0％, respectively. 5. Cortical thinning and expansion were observed in fibrous dysplasia and ossifying fibroma, and severe in ossifying fibroma than fibrous dysplasia, and those signs were not seen in periapical cemental dysplasia. Loss of lamina dura was dominant in fibrous dysplasia and root resorption was dominant in ossifying fibroma. Displacement of mandibular canal and the degree of the increase of vertical dimension were alike in both lesions. Displacement of maxillary sinus or nasal cavity, thinning & expansion of the maxillary sinus were dominant in fibrous dysplasia. 6. Polyostotic fibrous dysplasia was occurred at 5.9％, Multiple periapical cemental dysplasia at 43.7％. Occurrence rate in the edentulous area of fibrous dysplasia and ossifying fibroma were 7.0％, 8.6％, respectively.

• 대한소아치과학회지
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• 제24권2호
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• pp.352-360
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• 1997

구순 구개열 신생아는 출생시부터 수유의 어려움을 비롯하여 중이염, 언어장애, 부정교합, 부적절한 악안면 성장과 이로 인한 정신적 손상등에 직면하게 된다. 이런 복합적인 문제를 갖고 있는 신생아의 전반적인 치료를 위해서는 여러 관련분야 전문가들의 포괄적인 관리가 필요하다. 특히 수유의 어려움은 유아의 영양 상태를 좌우할 수 있는 중요한 문제이므로 가장 먼저 관리하여야 할 부분이다. Obturator의 사용은 수유보조의 역할 뿐만 아니라 구강과 비강을 구분하여 중이염의 발생빈도를 감소시키고, 구개판의 성장을 촉진시키며, 정상적인 구강 안면조직의 발달을 유도할 수 있다. 소아치과의사는 구순 구개열 신생아의 정상적인 성장, 발육을 위해 출생 직후 부모에게 적절한 수유방법의 조언과 함께 obturator 를 장착해 주고, 다른 team과 긴밀한 협진을 통해 유치열기, 혼합치열기까지 지속적으로 치과적 관리를 제공하여야 한다.

• 대한치과의사협회지
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• 제47권11호
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• pp.758-768
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• 2009

Purpose : Schulte introduced immediate implant cases in 1970s, since then many patients have been treated by immediate implants. The aim of this study was to evaluate the cumulative survival rate of immediate implant and to analyze various factors associated with survival of immediate implant in a 8-year period retrospectively. Materials and methods : From May, 2000 to October, 2007, 77 implants were placed in 63 patients immediately after tooth extraction at Department of Periodontology, Yonsei University Hospital. The implant survival rate was analyzed using a life-table analysis. After delivery of prosthesis, along 1 year of observation period, all implants were evaluated clinically and radiographically. Results : Among 77 implants, 59 were placed in maxilla and 18 in mandible. The most common site of the implantation was Mx anterior (65%). The overall survival rate was 94.8% over a mean follow-up period of $44.2{\pm}21$ months and the 8-year cumulative survival rate was 94.6%. Failure occurred in 4 implants, all of which were due to early failures. None of the following factors were significantly associated with the survival of immediate implants: advanced surgical technique including bone graft and guided bone regeneration, the types of implants, causes of tooth loss, and types of prosthesis. Conclusion : On the basis of 8-year life time analysis, immediate implant placement can be considered a safe and predictable treatment mordality.

• 대한치과보철학회지
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• 제57권4호
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• pp.374-381
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• 2019

넓은 영역의 무치악 부위를 수복하기 위한 전통적인 방법은 의치를 이용한 치료다. 하지만, 임플란트를 활용할 경우 보철물의 안정과 유지, 그리고 지지의 측면에서 더 유리하며, 저작효율이 향상되는 등 기능적으로 더 양호한 결과를 얻을 수 있다. 이 같은 임플란트를 이용한 치료방법은 크게 가철성과 고정성 방식으로 분류될 수 있으며, 치조골의 흡수정도, 악간관계, 환자의 선호도, 사회 경제적 요인 등을 고려하여 적절한 접근 방식을 선택하여야 한다. 한편, 지르코니아의 물성이 크게 개선됨에 따라, 임플란트 지지형 고정성 보철물의 재료로서 단일구조 지르코니아가 각광을 받고 있다. 단일구조 지르코니아는 지르코니아 코어에 세라믹을 비니어링 한 보철물이나 금속 도재관보다 파절과 chipping의 빈도가 적으며 지르코니아 자체가 충분한 두께를 가질 수 있어 구조적으로 좋은 물성을 지닐 수 있다. 최근에는 투명도가 증진된 단일구조 지르코니아도 출시되어, 전치부 보철물을 위한 재료로도 널리 사용되고 있다. 본 증례의 남환은 상악 양측 구치부의 결손 및 다수 잔존치의 중등도 이상의 전반적 만성 치주염 이환으로 인해, 하악 양측 견치 및 좌측 제1, 2 소구치를 제외한 모든 치아를 발치한 후, 상악 8개 및 하악 3개의 임플란트 식립을 동반한 전악 수복 치료를 받았다. 보철물 장착 후 1년 간의 경과 관찰 기간 동안 기능적, 심미적으로 만족할만한 결과를 얻어 이를 보고하는 바이다.

• 대한치과보철학회지
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• 제57권1호
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• pp.81-87
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• 2019

다운증후군은 영구치의 법랑질과 상아질 층이 얇아서 치아가 작고, 부정교합의 발생가능성이 높다. 특히 치주염의 빈도가 높으며 작고 불규칙한 치아 및 좁은 구개로 인한 부정교합의 발생가능성이 높고, 발치 지연이나 유치잔존의 가능성이 있다. 이런 다운증후군 환자에게 있어서 상악 이중관을 이용한 의치는 한가지 좋은 치료선택이 될 수 있다. 상악 이중관을 이용하면 교차교합을 해결해 줄 수 있을 뿐만 아니라 의치의 지지 및 유지에도 도움이 된다. 또한 향후 지대치 발치시에 수리가 쉬운 장점이 있다. 본 증례에서 다운증후군과 치과공포증을 가진 26세 여자 환자에서 상악에 잔존유치가 존재하고, 치아 갯수가 작으며, 잔존치아 대부분의 경우 법랑질저형성증(Enamel hypoplasia)을 보여주고 있었다. 또한 좁은 구개로 인한 전후 및 측방으로 교차교합 상태였다. 상악에는 전후 및 좌우 반대교합(Cross bite)을 극복하기 위해서 이중관을 이용한 가철성의치로 수복을 하였고, 하악의 경우는 마취없이 가능한 법랑질에 변연을 형성하여 전치부는 라이네이트로 구치부는 지르코니아로 수복을 시행하였다. 그 결과 발치와 마취없이 반대교합을 해결하였으며, 심미성과 기능성의 개선 및 환자의 삶의 질을 개선할 수 있었다.