• Restorative Dentistry and Endodontics
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• 제38권2호
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• pp.59-64
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• 2013

Apical surgery cuts off the apical root and the crown-to-root ratio becomes unfavorable. Crown-to-root ratio has been applied to periodontally compromised teeth. Apical root resection is a different matter from periodontal bone loss. The purpose of this paper is to review the validity of crown-to-root ratio in the apically resected teeth. Most roots have conical shape and the root surface area of coronal part is wider than apical part of the same length. Therefore loss of alveolar bone support from apical resection is much less than its linear length.The maximum stress from mastication concentrates on the cervical area and the minimum stress was found on the apical 1/3 area. Therefore apical root resection is not so harmful as periodontal bone loss. Osteotomy for apical resection reduces longitudinal width of the buccal bone and increases the risk of endo-perio communication which leads to failure. Endodontic microsurgery is able to realize 0 degree or shallow bevel and precise length of root resection, and minimize the longitudinal width of osteotomy. The crown-to-root ratio is not valid in evaluating the prosthodontic prognosis of the apically resected teeth. Accurate execution of endodontic microsurgery to preserve the buccal bone is essential to avoid endo-perio communication.

• 구강회복응용과학지
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• 제31권4호
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• pp.349-357
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• 2015

무치악 환자에 있어서 골유착 임플란트는 통상의 다른 보철수복방법과 비교했을 때, 기능적으로나 환자의 만족도 면에 있어서 아주 좋은 결과를 보이며, 삶의 질 향상에도 가장 우수한 것으로 알려져 있다. 골질이 양호하고 골량이 충분한 부위에 외과적으로 많은 수의 임플란트를 적절히 식립하여, 최상의 임플란트 보철물 설계가 가능하게 배열되는 것이 바람직하나, 아직까지는 환자와 치과의사 모두에게 합병증과 여러 문제들이 한계로 남아 있다. 골유착에 관한 보철적인 문제, 즉 임플란트 실패, 보철물의 부적합, 임플란트 구성요소의 파절, 그리고 나사 풀림 등 합병증에 관해 분석하고 그에 관한 증례를 보고하고자 한다.

• The Journal of Advanced Prosthodontics
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• 제2권2호
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• pp.58-60
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• 2010

Presurgical prosthetic treatment planning is critical for the success of the implant prosthesis. Inadequate treatment plan, due to insufficient discussion between prosthodontist, and surgeon, may result in poor prognosis. A 26-year-old male patient was referred for prosthodontic treatment after implant was placed in the area of teeth #17,16, 22, 25 and 27, without adequate discussion nor the treatment planning between oral surgeon and prosthodontist. It was found that the patient had two hopeless teeth, and a severely resorbed alveolar ridge. Additional tooth extraction was needed and the type of definitive prosthesis was shifted from fixed type to removable one. Proper pre-surgical treatment planning is essential for the good prognosis. Implant-supported removable prosthesis on milled bars may be a useful treatment option in patients with incorrect angled placement on severely resorbed alveolar ridge.

• 대한치과보철학회지
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• 제51권4호
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• pp.339-346
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• 2013

외상이나 선천적 결손에 의한 영구치아의 결손은 치료 방법과 적용 시기의 결정이 치료의 예후에 중요한 영향을 미친다. 본 증례는 성장기 환자로서 치아와 두개안면골 상태에 대한 정확한 진단 및 적절한 치료방법을 선택하고 성장 양식을 고려해서 일정기간 임시수복물과 임시 가철성 보철물을 사용하였으며, 성장 완료 후 임플란트 등을 이용한 고정성 보철수복 치료를 시행한 경우로써 교정과와 보철과의 협진 진료, 붕괴된 교합고경의 재확립 과정, 임플란트 보철치료 시 고려해야할 사항들에 대해 발표하고자 한다.

• 대한치과보철학회지
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• 제51권4호
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• pp.332-338
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• 2013

성공적인 보철 치료를 위해서는 정확한 진단이 근거가 되어야 한다. 즉, 처음 환자가 내원하였을 때, 환자의 주소를 바탕으로 한 문제점을 찾고, 그 원인을 분석하여 이에 입각한 치료 계획을 세웠을 때, 만족스러운 결과를 기대할 수 있을 것이다. 본 증례의 환자는 77세 여성으로, 저작 시 상 하악 좌측 소구치 부위의 통증 및 기존 보철물의 비심미성을 주소로 내원하였다. 임상적, 방사선학적 검사 및 모형 분석을 통해 문제점을 파악하였고, 여러 문헌에 근거하여 지대치 평가, 보철물의 여러 가지 디자인에 따른 예후 및 최종 보철물의 장착 시 유지 관리의 용이성 등을 고려하여 치료 계획을 수립하기로 하였다. 심미적 문제, 보철을 위한 악간 공간의 부족을 해소하고자 최소한의 수직 고경 증가를 동반한 전악 수복을 시행하기로 결정하였다. 기능, 심미성 및 교합의 안정을 통한 환자의 적응도를 평가하여 치료 계획의 적절성 여부를 판단할 수 있었다. 따라서, 최종적인 고정성 국소 의치를 제작하고 장착하여 만족스러운 결과를 얻었기에 이를 보고하는 바이다.

• 대한소아치과학회지
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• 제28권1호
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• pp.8-11
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• 2001

Langerhans Cell Histiocytosis는 Langerhans cell의 비정상적인 증식을 특징으로 하는 질환이다. 임상적 양상은 단독 골병소에서부터 여러 장기를 침범하여 치명적인 경우까지 매우 다양하게 나타나며, 나이가 어릴수록, 침범된 장기의 수가 많을수록 예후는 좋지 않다. 악골의 경우는 전체 Langerhans Cell Histiocytosis 환자의 $10\sim20%$에서 나타나며, 주로 초기에 이환된다. 본 환아는 만 3세 때 하악골 전반에 걸친 동통으로 본 치과병원에 내원하여 조직학적 검사를 통해 Langerhans Cell Histiocytosis임을 확진 받은 후 소아과에 의뢰되어 화학요법에 의해 치료되었다. 재발의 가능성이 있어 현재 주기적 검사 중이며, 하악 좌측 제2소구치배의 상실로 인해 향후 교정치료 및 보철치료가 필요하리라 사료된다. 본 증례는 치과병원에서 Langerhans Cell Histiocytosis임을 확진한 후 조기치료를 시행해 주어 양호한 결과를 얻었기에 보고하는 바이다.

• 대한심미치과학회지
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• 제8권1호
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• pp.36-44
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• 1999

No one really doubts that the hottest area of dentistry in 21st century would most likely be 'implant'. With the support of a vast amount of research, implant has been successfully and rapidly absorbed into the field of general dentistry including private practitioners. For teeth with hopeless(or refractory) periodontitis or periapical pathosis, with no hesitation most dentists would think extraction as the sole treatment option followed by prosthodontic replacement possibly including implant. Not many dentists would take Trasplantation/Replantation as another treatment option for a particular condition. Dentistry is often more focused on 'Restoration' than 'Preservation' of natural dentition. 'Biologic Implant' is obviously much closer to the concept of 'Preservation'. Many different types of biologic implant system have been introduced to clinical dentistry so far. Many of those have failed to earn reasonable acknowledgement despite of the clinical success they brought. For some reason biologic implant has rather been alienated for long time. RPI(Ring Pin Implant) is designed to improve the prognosis and success rate of transplanted/replanted teeth. RPI is a Ti-based custom made implant system. It is fabricated either by electric casting or milling process. The major feature RPI gas is the 'ring & hole' structure. The hole should be no less than 1mm diameter to allow bone bridge formation thru it. The ring structure and bone bridge formation creates anti-torque activity, which largely increases the 'initial stability' of the transplanted/replanted teeth. It is also reported that RPI is beneficial in the aspect of resisting root resorption following replantation/transplantation procedure.

• 한국표면공학회지
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• 제40권4호
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• pp.197-202
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• 2007

Fit of the restoration and its cementation procedure is crucial to both its short and long term prognosis. Marginal fit is affected by many variables during the fabrication process. These variables, being intrinsic properties of the materials or the clinical technique used, can cause changes in the size and shape of the definitive restoration. Even if all variables are controlled carefully, the seating of a restoration can still be affected due to insufficient space for the luting agent. The use of die spacer can reduce the elevation of a cast restoration of a prepared tooth, decreased seating time, improve the outflow of excess cement, and lower the seating forces. The purpose of this study was to evaluate the marginal fidelity according to die spacer application times and measurement site. Casting alloys were prepared and fabricated using non-precious metal at $950^{\circ}C$. Specimens are divided into four groups: I(die spacer painted casting for wax pattern), II(die spacer non painted casting for wax pattern). The specimens were cut and polished for marginal gap observation. The marginal gap was observed using scanning electron microscopy (SEM).

• Maxillofacial Plastic and Reconstructive Surgery
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• 제33권4호
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• pp.352-358
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• 2011

Purpose: This study evaluated the prognosis and survival rate of SLA (Sandblasted, Large-grit and Acid-etched) implants and it also evaluated the prosthodontic complications and the associated factors. Methods: Twenty seven patients (14 men and 13 women, mean age: 54.9) who visited Chosun University Hospital Implant Center with the chief desire for placement of an implant in an edentulous area from March, 2008 to December 2008 and who received placement of a SLA implant ($Implantium^{(R)}$, Dentium Co., Korea) were selected for this study. Results: The average follow-up period was 15 months and the study was based on the treatment records, radiographs and clinical examinations. A total of 69 implant cases were retrospectively assessed for the width and length of the implant, the primary and secondary stability, the combined surgery, the employed bone graft material and barrier membrane, the status of the opposing tooth, implant failure and the prosthetic complications. During the follow-up period (average: 15 months), the accumulative survival rate of the 69 implants in 27 patients was 100%. Complications such as infection, sinusitis and fixture exposure after surgery were seen for 5 implants in 4 patients. Complications such as screw loosening, contact loosening and peri-implant gingivitis after prosthodontic treatment occurred in 7 cases (10.14%). Conclusion: This study reports placement of SLA implants may cause various complications, yet the final accumulative survival rate was 100%. The SLA implant ($Implantium^{(R)}$) has an excellent clinical survival rate and outcome.

• 구강회복응용과학지
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• 제16권2호
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• pp.149-159
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• 2000

Occlusal disease is comparable to periodontitis in that it is generally not reversible. Occlusal disease, however, like periodontitis, often maintainable. It does itself to treatment and when restorative dentistry is utilized it becomes, in that sense, reversible. Moreover, a systematized and integrated approach will lead to a prognosis that is favorable and predictable. This approach facilitates development of optimum oral function, comfort, and esthetics, resulting in a satisfied patient. Such a systematized approach consists of four logical phase : (1) patient evaluation, (2) comprehensive analysis and treatment planning, (3) integrated and systematic reconstruction, and (4) postoperative maintenance. An integrated treatment plan is first developed on one set of diagnostic casts, properly mounted on a semiadjustable articulator using jaw relationship records. This is accomplished by using wax to make reconstructive modifications to the casts. These modified casts become the blueprint for planned occlusal changes and the fabrication of provisional restorations. The treatment goals are : (1) comfortably functioning temporomandibular joints and stomatognathic musculature, (2) adherence to the basic principle of occlusion advocated by Schuyler, (3) anterior guidance that is in harmony with the envelope of function, (4) restorations that will not violate the patient's neutral zone. This report shows the treatment procedures for a patient whose mandibular position has been altered due to posterior bite collapse. Migration of the maxillary anterior teeth had occurred, and the posterior occlusal contacts showed pathologic interference. Precise diagnosis using mounted casts was executed and prosthodontic reconstruction by the aid of an unconventional orthodontic correction on maxillary flaring was planned. An unconventional orthodontic correction can be accomplished by using preexisting natural teeth, which can be modified for use in active tooth movement or splinted together for orthodontic anchorage. This technique has an advantage over conventional fixed appliance orthodontic therapy because it can accomplish tooth movement concurrently with restorative and periodontal therapy. On occasion, minor tooth movement can be necessary to achieve the optimum occlusal scheme, crown form, and tooth position for the forces of occlusion to be displaced down the long axis of the periodontally compromised teeth. Once the occlusion, periodontal health, and crown contours for the provisional splinted restoration are acceptable, the final splinted restoration can be similarly fabricated, and it becomes an excellent orthodontic retainer.