• 치과방사선
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• 제28권1호
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• pp.171-191
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• 1998

The present study was designed to elucidate the effects of the Co-60 γ irradiation and/or calcium-deficient diet on the periodontal tissue formation in rat pups. The pregnant three-week old Sprague-Dawley rats were used for the study. The experimental group was divided into two groups, irradiation/normal diet group (Group 2) and irradiation/calcium-deficient diet group (Group 3). The control group was non-irradiation/normal diet group (Group 1). The abdomen of the rats at the 19th day of pregnancy were irradiated with single absorbed dose of 350 cGy. The rat pups were sacrificed on the 14th day after delivery, and the maxillae including molar tooth germ were taken. The specimens including the 1st molar tooth germ were prepared to make tissue sections for light and transmission electron microscopy. Some of tissue sections for light microscopy were stained immunohistochemically with anti-fibronectin and anti-osteonectin antibodies. The results were as follows; 1. In the periodontal ligament forming area, the fibroblasts of Group Z showed irregular arrangement and low activity. The immunoreactivity between the fibroblasts and collagen fibers was decreased, compared with Group 1. The fibroblasts of Group 3 showed atrophic change and clumped nucleus. The collagen fibers showed cystic change and low immunoreactivity to the fibronectin. 2. In the cementum forming area, the cementoblasts of Group 2 showed decrease of number and atrophic change. The cementoblasts of Group 3 showed edematous change, atrophy of cytoplasm, and clumping of nucleus. 3. In the alveolar bone forming area, the bone of Group 2 was thin and various degree of immunoreactivity to the osteonectin. Group 3 showed edematous osteoblasts, fibrous degeneration of bone marrow, and weak immunoreactivity to the osteonectin.

• 대한치과보철학회지
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• 제18권1호
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• pp.99-109
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• 1980

An investigation was made Into 1,357 fixed bridges which had been performed at the Department of Prosthetic Dentistry, Seoul National University Hospital from 1973 to 1979. The purpose of this investigation was to establish a basic reference of the treatment with fixed bridges by obtaining statistical conclusions from the data concerning the patients who had been treated with fixed bridges. The following conclusions were obtained; 1. The ratio of the fixed bridges made on the maxillae to those made on the mandible was 1:1. 2. The cases of fixed bridges with one pontic were the most frequent, i.e., 946 cases out of total 1,357 cases, which were 69.7% of the total. 3. As the number of missing teeth increased, the number of the relevant cases of fixed bridges decreased. 4. The most frequent age group of the patients who had been treated with fixed bridges was the twenties, which was 40.8% of the total. As the age of the patients increased, the number of corresponding cases of fixed bridges decreased. 5. Most of the fixed bridges with more than three pontics were made at the anterior portion samely on the maxilla and on the mandible. 6. As for the retainers, the porcelain fused to metal crown and the partial veneer crown were frequently used at the anterior portion, while the full veneer crown was frequently used and the inlay and the attachment were used in some cases at the posterior portion. The locations of fixed bridges in the order of their frequency were: canine, lateral incisor, second bicuspid, central incisor, second molar, first bicuspid, first molar, and third molar on the maxilla; second bicuspid, second molar, first bicuspid, first molar, canine, third molar, lateral incisor, and central incisor on the mandible.

• Journal of Periodontal and Implant Science
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• 제37권2호
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• pp.151-164
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• 2007

Objective: The sinus floor elevation procedures have been used to facilitate implant placement in the severely atrophic posterior maxilla. Many variables may have an influence on the outcomes of the sinus floor elevation in combination with implant treatment. The aim of this study was to analyze survival rate of implants placed in the edentulous maxillae of patients in whom sinus floor elevation was undertaken according to variables. Materials and Methods: It consisted of 96 patients(50 male and 46 female), ranging in age from 31 to 70 years(mean 49 years), who underwent sinus floor elevation procedure(94 implants in left side and 106 implants in right side) from 2001 to 2002. A total of 200 implants were placed in the grafted sinus(73 implants in lateral approach and 127 implants in crestal approach). All implants were restored by fixed prosthesis. All patients were healthy. Follow-up periods for implants were between 48 to 60 months. Results: The cumulative survival rate of implants was 91.5%. Gender, age and operation site did not have an influence on the survival rate. There was statistically significant differences for the implants which placed in less than 4 or 5 rom residual bone height, the survival rate was 60%, 81.4% respectively (p<0.05). There was no statistically significant difference of implants survival rate ac- cording to approach technique. The survival rate for 100% autogenous bone grafts was lower with respect to composite grafts containing autogenous bone and 100% substitutes. The survival rate for hydroxyapatite-coated implants was statistically significant lower than other textured group (p<0.05). Conclusion: Residual bone height, surface texture and graft materials have an influence on the survival rate. To use autogenous bone as a part of a composite bone replacement, implant texture which leads to more favorable implant-bone interface were necessary. To determine residual bone height for initial implant stability was important.

• 구강회복응용과학지
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• 제27권2호
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• pp.223-231
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• 2011

본 증례 보고의 목적은 상악 무치악 환자에서 임플란트 지지 피개의치를 위한 $Locator^{(R)}$ attachment가 장착된 새로운 milled titanium bar를 소개하고 새로운 대안으로써의 가능성을 제시하고자 함이다. 56세 남자 환자가 상악 고정성 보철물(10-유닛 브릿지)의 동요도를 주소로 본원에 내원하였다. 악관절 및 치과 치료에 영향을 줄만한 특이한 전신병력은 없었다. 방사선 검사 및 임상 검사 결과, 상악의 경우 모든 잔존치아에서 심한 골흡수와 동요도를 보이고 있어 전악 발치를 시행한 후, 임플란트 지지 피개의치를 제작하기로 하였다. 의치의 안정성과 유지력, 저작효율, 청소의 용이성, 심미성과 발음 그리고 경제적인 측면을 고려하여 $Locator^{(R)}$ 어태치먼트를 CAD/CAM으로 제작된 milled titanium bar에 탭핑(tapping)으로 연결시키는 새로운 디자인을 고안하였으며, 1년 이상 경과 후, 기능과 심미적인 면에서 만족할 만한 성과를 얻었기에 이를 보고하는 바이다.

• Restorative Dentistry and Endodontics
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• 제45권2호
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• pp.20.1-20.14
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• 2020

Objectives: To minimize the tooth sensitivity caused by in-office bleaching, many dentists use non-steroidal anti-inflammatory drugs and topical desensitizing gels containing potassium nitrate and sodium fluoride. This study aimed to evaluate the influence of these substances on inflammation and the expression of substance P and calcitonin gene-related peptide in pulp nerve fibers. Materials and Methods: Seventy-two rats were divided into 6 groups as follows: GI, control; GII, only dental bleaching; GIII, only ibuprofen; GIV, ibuprofen administered 30 minutes before and after the bleaching treatment and every 12 hours until the analysis; GV, only topical application of a desensitizing agent; and GVI, topical application of a desensitizing agent before dental bleaching. Placebo gel was applied to the upper left jaw and the bleaching agent was applied to the upper right jaw in all groups. Subsequently, the groups were divided into 3 subgroups based on the time of analysis: 0, 24, and 48 hours after bleaching (n = 8). The rats were euthanized and the maxillae were processed and evaluated by histopathological and immunohistochemical analyses. The data were analyzed using the Kruskal-Wallis test, followed by the Dunn test (p < 0.05). Results: In the bleaching groups, the inflammatory process and expression of neuropeptides decreased over time. The animals in which a desensitizing agent was applied showed better results within 24 hours. Conclusions: The use of a desensitizing agent had positive effects on inflammation and pain-related neuropeptide expression, minimizing the painful effects of dental bleaching treatment.

• Applied Microscopy
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• 제26권1호
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• pp.59-65
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• 1996

누에의 사료에 대한 섭식성 반응이 다른 2계통에 대한 두부의 형태적 차이를 전자현미경적 관찰을 하였다 이들 2계통의 두부와 촉각의 형태적 차이는 변이가 심하고 다양하다. 섭식성 반응이 높은 계통에 있어서는 소시지의 돌기가 매우 잘 발달되어 있는 반면 섭식성 반응이 낮은 계통에 있어서는 형태적으로 퇴화되어 있다. 또한 촉각의 셋째마디의 유병돌기가 발달되어 있지 않으며 사료에 대한 섭식 반응이 낮고 극단적으로 퇴화되어 있는 개체는 사료를 감지하지 못하여 결국에는 굶어 죽은 것으로 사료된다.

• The Journal of Advanced Prosthodontics
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• 제11권2호
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• pp.88-94
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• 2019

PURPOSE. This study was conducted to investigate patterns of adjacent tooth displacement in the posterior implant with interproximal contact loss (ICL) by 3-D digital superimposition method. MATERIALS AND METHODS. Posterior partially edentulous patients, restored with implant fixed partial prostheses before 2011 and suffered from food impaction of ICL between 2009 and 2011, were included. Two dental casts, at the time of delivery and at the time of food impaction in a same patient, was converted into 3-D digital models through scanning and superimposition was performed to assess chronologic changes of the dentition. Directions of tooth displacement were evaluated and the amount of ICL was calculated. Correlations between the amount of ICL and elapsed time, or between the amount of ICL and age after function, were assessed at a significance level of P<.05. RESULTS. A total number of 13 patients (8 males, 5 females) with a mean age of $65.76{\pm}9.94years$ and 17 areas (4 maxillae, 13 mandibles) were included in this retrospective study. Teeth adjacent to the implant restoration showed complex displacements but characteristic tendency according to the location of the arch. The mean amount of ICL was $0.33{\pm}0.14mm$. Elapsed time from function to ICL was $61.47{\pm}31.27months$. There were no significant differences between the amount of ICL and elapsed time, or age (P>.05). CONCLUSION. Natural teeth showed various directional movements to result in occlusal change in the arch. The 3-D superimposition of chronologic digital models was a helpful method to analyze the changes of dentition and individual tooth displacement adjacent to implant restoration.

• 구강회복응용과학지
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• 제36권4호
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• pp.289-295
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• 2020

비심미적인 임플란트유지형 보철물의 심미성 개선은 매우 어려운 문제이며 특히, 상악 전치부 임플란트와 관련되어 있는 경우는 더욱 그러하다. 본 증례는 상악전치부 임플란트의 주기적 배농과 비심미성을 주소로 보철과의사로부터 의뢰된 69세 남자 환자의 심미성 개선에 관한 보고이다. 임플란트는 다소 깊게 식립되어 긴 임상치관길이를 보였으며, 주변 연조직 양도 부족하였다. 임상 검사와 방사선검사 후, 깊게 식립된 임플란트의 제거 대신 예후가 불량한 인접 치아의 발치 후 임플란트를 추가 식립하여 임플란트 유지형 고정성보철물을 제작하고, 깊게 식립된 임플란트는 제거 대신 치조제 증대에 도움을 주기 위해 침수(submergence)시켜 치조제를 증대시키는 방식을 선택하였다. 적절한 진단이 동반된 임플란트 침수가 전치부의 임플란트 비심미성을 개선시킬 수 있는 또다른 대안이 될 수 있을 것이다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권6호
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• pp.644-651
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• 2000

In cases of severe alveolar bony resorption in the edentulous posterior maxillae, implant placement is limited anatomically due to maxillary sinus. If the ridge is atrophic, the various bone grafting methods are required for the ridge augmentation. But the result of the onlay grafting procedure is not always promising. On the posterior maxilla, maxillary sinus mucosa lifting and bone grafting into the sinus floor, subantral augmentation(SA) technique are recommended. Various SA procedures have been developed for implant installation. We perfer to simultaneous block bone graft and implant installation through the residual alveolar ridge into the grafted block bone to fix the grafted bone and to gain the primary stability of the installed fixture. When a sagittal skeletal discrepancy in present due to the severe alveolar bony resorption of the maxilla, the advancement of the maxilla by Le Fort I osteotomy simultaneously with installation of implant fixtures combined with sinus lifting and interpositional bone graft procedure can be indicated. We applied various SA techniques for implant installtion to the 46 edentulous posterior maxillae, and total 154 implants were installed at our department from 1992 to 1999. Various SA techniques were classified in detail and the indications of each techniques were discussed. The changes of residual bony height following SA procedure were studied. The results were as follows. 1. The SA procedure combined with bone graft and simultaneous fixture installation were performed in 41 cases, 126 fixtures were installed and 5 fixtures were removed out of them. Le Fort I osteotomy procedure combined with sinus lifting and interpositional bone graft simultaneous with fixture installation were performed in 5 cases. Total 28 fixtures were installed and 2 fixtures were removed so far. 2. Autogenous block bone graft into sinus floor were performed in 35 cases, autogenous particulated marrow cancellous bone(PMCB) graft in 9 cases, and demineralized human bone powder in 2 cases. The donor site for bone graft were anterior iliac bone in 39 cases, posterior iliac bone in 3 cases and mandibular symphysis in 1 case and mandibular ramus in 1 case. 3. In 9 cases with which SA procedure had been performed with the block bone graft, the change of pre- and postoperative residual bony height were measured using MPR(multiplanar reformatted)-CT. The mean residual bony height was 8.0mm preoperatively, 20.2mm at 6 months following up operation and we gained average 12.2mm alveolar bony height. So, we can recommend this one-stage subantral augmentation and fixture installation technique as a time conserving, safe and useful method for compromised posterior edentulous maxilla.

• 대한치과교정학회지
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• 제32권6호
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• pp.413-424
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• 2002

성장기 아동에서 상악골 열성장을 보이는 제III급 부정교합은 상악골 전방 견인 장치의 적응증이 된다. 상악골 전방 견인장치의 바람직한 효과는 상악골의 전방 이동이지만, 실제로는 상악 치아의 전방 이동, 하악골의 후하방 회전, 하악 전치의 설측 이동 등의 복합적인 결과로 III급 관계가 개선된다고 알려져 있다. 그러나 수직적 안모 유형별로는 상악골 전방 견인 장치의 효과에 대한 차이는 잘 알려진 바가 없다 본 연구는 1998년-2000년 사이에 연세대학교 치과병원 교정과에 내원한 환자들 중 초진시 나이는 6세 6개월에서 13세 3개월 사이의 상악골 열성장을 동반한 제 III급 부정교합으로 진단된 67명 (남 36, 여 31)을 대상으로, 안모유형별로 SNMP군과 Gonial angle군에서 low, average, high로 세부군을 나누어 치료전 측모 두부방사선 규격사진을 통해 상악골 전방견인 장치의 효과를 비교하여 다음과 같은 결과를 얻었다. 1) SNMP군의 low angle에서 B point의 후방이동량이 많았으며, High angle에서는 A point의 전방이동량이 컸다. 2) Genial angle군의 low angle에서 A point의 전방이동양이 가장 적었으며, high angle에서는 A point의 전방이동량이 상대적으로 많았다. 3) A point에 대한 arcTan를 구한 결과 A point의 이동 각도는 장안모 군에서 더 수평적인 이동 양상을 보였고, 단안모 군에서는 수직적 이동양상이 강했다. 4) SNMP군과 Gonial angle의 세부군에서 치료기간별 유의성은 없었다.