• 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.

• 한국정보전자통신기술학회논문지
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• 제15권1호
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• pp.62-68
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• 2022

의술과 경제적 발전으로 인해 예쁘고 건강한 치아를 복원 또는 유지하기 위해 다양한 치료 방법들이 연구되고 있으며 특히 치아의 손실을 복원하는 보철치료, 미백과 같은 심미 치료 시술에 대한 관심이 증가하고 있다. 보철 및 심미 치료 분야에 있어 중요한 것 중 하나가 치아의 정확한 색상을 결정하는 것인데 이는 자연치와의 조화가 심미 보철물의 완성도를 결정 짓는 중요한 요소이기 때문이다. 본 연구는 스마트폰을 카메라를 활용하여 치아 측색 위한 측색 애플리케이션 개발에 대한내용으로서, 측색 애플리케이션 UI를 설계하고, 측색 알고리즘을 도출하여 애플리케이션을 구현하였으며, 구현된 애플리케이션에 대한 테스트를 통해 유효성에 대한 검증을 진행했다.

• Restorative Dentistry and Endodontics
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• 제36권6호
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• pp.515-520
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• 2011

전치부 치간이개를 치료할 때 가장 어려운 것은 레진으로 축성 후 치아 사이의 "black triangle"없이 치간공극을 메우는 것이다. 이를 위해서는 치경부 형태와 접촉점의 위치에 기초하여 치은 형태를 결정하는 것이 중요하다. 이 증례보고는 적절한 접촉점을 형성하기 위해 비침습적 방법을 사용하여 접촉점의 위치를 설정하였다. 또한 치은-치아 사이에 위치한 Mylar strip을 이용한 기존의 방법을 바꾸어 자연스러운 형태를 갖도록 변형하였다. Mylar strip을 치은연 상방으로 약 1 mm 정도 되게 치은열구에 위치시키고 작은 면구를 치은과 그 사이에 위치시켜 출현윤곽(emergence contour)을 부여하였다. 이와 같은 변형된 방법은 적절한 출현윤곽과 치은형태를 형성하는데 유용하였으며, 임상적용에 유효하였다.

• 대한심미치과학회지
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• 제24권2호
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• pp.86-100
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• 2015

남아있는 자연치아와 어울릴 수 있도록 치과의사와 치과기공사는 최선의 노력을 다한다. 기능성과 심미성을 완벽하게 재현한 세라믹은 큰 감동을 환자에게 전달해 주고 있다. 그러나 쉽지 않은 문제들을 극복해내야 한다. 서로 다른 두 물체가 완벽하게 같은 스펙트럼 곡선을 가지는 일은 거의 있을 수 없다. 스펙트럼 곡선과 반사율은 물체만의 고유한 특징이다. 지문과 같다고 할 수 있다 그렇기에 우리가 보통 색을 맞춰준다라고 이야기하는 것은 스펙트럼 곡선을 동일화 하는 것이 아니라 우리가 인지하는 색의 조합을 같은 것으로 만들어 주는 조건 등색 과정을 이해해야 한다. 즉, 우리 분야에서 살펴 보자면 색을 맞추려는 환자의 자연치아와 세라믹이 우리 망막의 원추체를 같은 조합으로 자극하게 맞춰주는 과정이다.

• 구강회복응용과학지
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• 제20권1호
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• pp.57-70
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• 2004

The significance of occlusion has regained its popularity in dentistry with the introduction of implant therapy. Literature has reported that the clinical success and longevity of dental implants can be achieved by biomechanically controlled occlusion. Occlusal overload is known to be one of the main causes for implant failure. Evidences have suggested that occlusal overload contribute to early implant bone loss as well as deosseointegration of successfully integrated implants. Unlike natural teeth, osseointegrated implants are ankylosed to surrounding bone without the periodontal ligament (PDL) which provides mechanoreceptors as well as shock-absorbing function. Moreover, the crestal bone around dental implants may act as a fulcrum point for lever action when a force (bending moment) is applied, indicating that implants/implant prosthesis could be more susceptible to crestal bone loss by applying force. Hence, it is essential for clinicians to understand inherent differences between teeth and implants and how force, either normal or excessive force, may influence on implants under occlusal loading. The purposes of this paper are to review the importance of implant occlusion, to establish the optimum implant occlusion with biomechanical rationale, to provide clinical guidelines of implant occlusion and to discuss how to manage complications related to implant occlusion.

• 대한치과보철학회지
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• 제32권2호
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• pp.181-194
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• 1994

The purpose of this study was to compare the retention and fitness of crown treated with various desensitizing agents on natural teeth. Varnish, dentin primer, bonding agent and potassium oxalate treated groups and control group with no treatment were used. The retention test was executed with the Instron test machine(Instron Co.,U.S.A.) on 24 hours after cementation with zinc phosphate cement. After retention test, the teeth and crowns were washed and recemented. The cemented crowns were embedded in clear resin and sectioned with a diamond saw. The occlusal and marginal fitnesses, were measured indirectly with a stereomicroscopic photographs. The result of this study were obtained as follows : 1. The retention of control group was higher than any other desensitizing agent treated group. 2. The differences of retention among varnish, dentin primer, bonding agent and potassium oxalate treated groups were not statistically significant. 3. There were no statistically significant difference in fitness at occlusal surface and margin among control, varnish, dentin primer, bonding agent and potassium oxalate treated groups. According to these results, desensitizing agents used to protect the pulp from irritation of luting agents may adversely affect the retention of castings. Therefore, desensitizing agents should be used in limited areas carefully.

• 대한치과교정학회지
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• 제48권2호
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• pp.125-130
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• 2018

Traumatic dental injury is considered a public dental health problem because of a high childhood incidence, high treatment costs, and prolonged treatment time. Although management guidelines for traumatized teeth have been outlined, tooth loss following trauma is occasionally unavoidable. Here, we describe the successful interdisciplinary management of a traumatized central incisor in an 11-year old boy that was extracted because of a poor prognosis and restored by the autotransplantation of an immature donor tooth into the site. The patient underwent orthodontic treatment in order to close the donor site space and bring the autotransplanted tooth to an ideal position. Postorthodontic treatment radiographs and photographs revealed an esthetic and functional natural tooth replacing the lost tooth. The findings from this case suggest that autotransplantation offers unique advantages as a treatment modality for the restoration of missing teeth, particularly in growing children.

• 대한치과보철학회지
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• 제35권2호
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• pp.255-264
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• 1997

The conventional osseointegration protocol calls for waiting up to 12 months for ossification of an extraction socket to heal before placing an endosseous implant. In this study, the possibility of placing a pure titanium implant directly into an extraction socket immediately after extraction was investigated. And the marginal bone loss of immediate nonsubmerged and submerged endosseous dental implants placed into extraction sockets was also compared. Pure titanium Nobelpharma Branemark implants and solid screw type ITI implants were placed into premolar extraction sockets of two adult dogs and allowed to heal for a period of 3 months, followed by functional loading of the implant. Radiographic examination was performed before implantation, immediately after implantation and 3, 6, 9, 12 months after implantation. The results obtained were as follows : 1. Immediately placed nonsubmerged ITI implants and submerged Branemark implants showed favorable radiographic osseointegration status and there were minimum marginal bone loss. 2. There were no significant differences in radiographic finding of osseointegration between conventional and immediate implantation. 3. Gingival tissue around implants showed more inflammatory signs than that of adjacent natural teeth. This study suggest that pure titanium Branemark implants and submerged ITI implants have the potential to integrate when placed immediatly after extraction of the teeth and warrants further investigation.

• 대한치과보철학회지
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• 제35권3호
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• pp.535-543
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• 1997

In order to compare the accuracy of impression technique using the addition silicone putty and improved heavy body material, impression were taken for the natural 6 maxillary anterior teeth, and for the metal mast model that has full arch shape with 4 cylindrical abutment teeth. Marginal gingiva was retracted by routine method using retraction cord, and two techniques were tried to compare the length of impression materials in the gingival sulcus. This was aimed to see the effect of viscosity and hydraulic pressure of impression materials for the subgingival impression. Impressions for the full arch-shaped metal master model were taken to compare the linear stability of the different impression materials and their related techniques. The conclusions were as belows : 1. The one-step impression technique showed longer extension of impression material in gingival sulcus than two-step impression technique. 2. High viscosity and hydraulic pressure of impression material were useful to take subgingival impression. 3. There was no statistically significant difference for the two-dimensional accuracy of impression technique, but two-step technique showed better trend than one-step technique.

• 구강회복응용과학지
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• 제31권4호
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• pp.364-370
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• 2015

최근 구치부 부분 무치악 환자의 임플란트 보철 수복은 기능적뿐만 아니라 심미적으로도 환자의 만족을 이끌어내야 하는 과제를 안고 있다. 이렇게 환자의 요구가 높아지면서 상실된 자연치아와 유사한 형태의 임플란트 보철을 사용한 구강회복이 보철수복의 중요한 이슈가 되고 있다. 이를 위해서는 기성 지대주 보다는 더 넓은 customized CAD/CAM 지대주를 사용함으로써 자연스러운 출현윤곽을 재현할 수 있다. 넓은 지대주를 지지해주기 위해서는 충분한 폭과 높이를 가지는 각화치은이 존재해야 하는데, 만약 긴 치아상실기간이나 골이식술 등으로 인해 임플란트 주위에 각화치은이 부족한 경우에는 연조직 증대술을 시행하는 것이 추천된다. 이러한 과정을 통해 심미적이고 기능적인 임플란트 보철 제작이 가능하며 구강위생관리를 용이하게 하고 향후 임플란트 주위염의 발생 가능성을 감소시킨다. 본 증례는 구치부 부분 무치악 환자에서 골이식술, 상악동 이식술, 임플란트 식립술 및 연조직 이식술을 사용하여 부족한 치조골과 각화치은 및 협측전정을 회복하였으며, customized CAD/CAM 지대주와 지르코니아 보철물을 이용하여 수복한 증례로 주기적인 내원 및 검사를 통해 기능적, 심미적으로 만족할만한 결과를 얻었기에 이 사례를 보고하고자 한다.