• Imaging Science in Dentistry
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• 제31권3호
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• pp.165-173
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• 2001

Objectives : To evaluate the absorbed and effective doses of spiral and computed tomography for the dental implant planning. Materials and Methods: For radiographic projection, TLD chips were placed in 22 sites of humanoid phantom to record the exposure to skin and the mean absorbed dose to bone marrow, thyroid, pituitary, parotid and submandibular glands and nesophagus. Effective dose was calculated, using the method suggested by Frederiksen et al.. Patient situations of a single tooth gap in upper and lower midline region, edentulous maxilla and mandible were simulated for spiral tomography. 35 axial slices (maxilla) and 40 axial slices (mandible) with low and standard dose setting were used for computed tomography. All the radiographic procedures were repeated three times. Results: The mean effective dose in case of maxilla was 0.865 mSv, 0.452 mSv, 0.136 mSv and 0.025 mSv, in spiral tomography of complete edentulous maxilla, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). That in case of mandible was 0.614 mSv, 0.448 mSv, 0.137 mSv and 0.036 mSv, in spiral tomography of complete edentulous mandible, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). Conclusions: Based on these results, it can be concluded that low mAs computed tomography is recommended instead of spiral tomography for the complete edentulous maxilla and mandible dental implant treatment planning.

• The Journal of Advanced Prosthodontics
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• 제6권1호
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• pp.53-59
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• 2014

PURPOSE. The aim of this study was to obtain statistical data on the residual bone height at different natural tooth positions by panoramic radiography in edentulous Korean patients aged 60-90 years. MATERIALS AND METHODS. The study included the diagnostic panoramic radiographs of 180 randomly selected edentulous patients without systemic diseases affecting bone. The radiographic selection criteria included absence of obvious facial asymmetry, clearly visible anatomic structures, and no surgical and fracture history. The panoramic radiographs of 79 patients met these criteria and were used in the analysis. The same researcher processed all the radiographs by using a standardized method. The height of the residual bone was measured at 18 predetermined sites (7 in the maxilla and 11 in the mandible) on digitized and printed radiographs by using a Digimatic caliper, triangle, and ruler. Gender- and age-related differences were statistically analyzed by using the t-test and rank-sum test (${\alpha}=0.05$). RESULTS. The maxillary residual bone height did not show significant gender-related differences, but male patients had significantly higher residual bone in the mandible(P<.05). No significant height differences at the measured sites were noted among the 60s, 70s, and 80s age groups. CONCLUSION. Dentists should pay greater attention to older female edentulous patients because they are more prone to rapid residual bone resorption. Residual bone resorption may not be affected by age.

• 대한치과보철학회지
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• 제32권2호
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• pp.235-248
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• 1994

There were many studies that distribute the partial edentulous states and examine the removable partial denture designs in the planning of removable partial denture treatment. This study was performed in the point of removable partial denture prescription to evaluate partial edentulism and its removable partial denture designs. The data was collected from the dental laboratory of each three dental colleges in Seoul and from two dental laboratories only for removable partial dentures as a prescription form. A total of 1411 cases with prescription form collected from dental laboratories were distributed for this study, then 788 cases were selected for this study. The case selection was done according to the contents of prescription form. The selected cases were divided into maxillary arch and mandibular and classified in terms of types of major connector and direct retainer, unbroken anterior teeth, Kennedy classification, the number of remaining teeth, and distribution of age and sex. The analyzed results were as follows : 1. The Kennedy classification I showed highest frequency both in maxilla and mandible. 2. The arch distribution of removable partial denture was 50.08% for maxilla and 49.92% for mandible. 3. The highest frequency in the distribution of direct retainer was the RPA clasp design. 4. The frequency of unbroken anterior 6 was 73.36% for maxilla and 82.30% for mandible. 5. The design of broad palatal strap and lingual bar revealed the highest prevalence in the major connector construction. 6. The mean number of remaining teeth per arch was 8.25 for maxilla and 8.37 for mandible. 7. The mean age of the patients supplied with removable partial denture was 52.25 years for men, 51.68 years for women, 52.11 years for maxilla, and 51.76 years for mandible and women showed more prevalence.

• 대한치과보철학회지
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• 제40권1호
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• pp.88-97
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• 2002

The purpose of this study was to evaluate a cases which was treated with magnetic attachments on the patients in edentulous mandible and maxilla. Author made magnetic overdenture for two patients and then clinical examination were used for evaluation of the function and change in retention during 30months. Patients showed difficulty in oral hygiene care at the beginning but they go used to it soon. It was effective in promotion of denture retention and stability and also gave patient emotionally uplifting psychologic state. This study suggest that magnetic attachment was effective for the treatment of patients presenting a few remaining teeth or teeth under severe caries or mobility.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권6호
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• pp.481-485
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• 2009

Cemento-osseous dysplasias are a group of disorders known to originate from periodontal ligament tissues and involve, essentially, the same pathological process. They are usually classified, depending on their extent and radiographic appearances, into three main groups. Periapical cemental dysplasia predominantly involves the periapical region of the anterior mandible. Florid cemento-osseous dysplasia presents with multifocal lesions in the tooth bearing or edentulous areas of the maxilla and mandible, often occurring bilaterally with symmetric involvement. Focal cemento-osseous dysplasia exhibits a single site of involvement in any tooth bearing or edentulous area of the mandible or maxilla, with the posterior mandible representing the most common site. We report the clinical, radiographic and histological findings of 3 types of cemento-osseous dysplasia with a review of literatures.

• 대한치과보철학회지
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• 제56권1호
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• pp.25-30
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• 2018

무치악 환자에서 임플란트 고정성 보철 수복의 장점은 안정성, 편안함을 들 수 있으며, 생물학적 측면으로는 하악골 흡수를 방지할 수 있고 저작기능이 향상된다는 이점이 있다. 그중 하이브리드형 보철 수복은 하악골 이공사이에 4 - 6개의 임플란트를 식립하고 양쪽 원심으로 캔틸레버를 만들어 구치부 치아를 대체하게 된다. 본 증례는 85세 여성 환자로 상하악의 무치악 상태로 본원에 내원하였다. 상악의 가철성 총의치, 하악의 임플란트 하이브리드형 보철물로 최종 치료하여 치료 후 기능적, 심미적으로 만족스러운 결과를 얻었기에 이를 보고하고자 한다.

• 대한심미치과학회지
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• 제8권1호
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• pp.46-59
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• 1999

A fixed bridge is preferred as a prosthetic option supported by oral implants. However, it is very difficult to re tore edentulous maxilla with fixed prosthesis in cases with improper position and angulation of fixtures, abnormal jaw relation, and need for proper lip support. Six Br${\aa}$nemark implants were installed in edentulous maxilla opposing mandible with natural dentition. A removable hybrid prosthesis attached to a bar milled by 6 degrees was therefore designed to overcome such disadvantages of fixed prosthesis. Lateral stabilization of removable prosthesis was obtained by framework closely fitting the milled bar. Support for the prosthesis was ensured by three elevated areas on the bar. Two precision attachments(CEKA REVAX) provided appropriate direct and indirect retention without influencing support. A clinical and laboratory procedure was presented.

• 대한치과보철학회지
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• 제59권1호
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• pp.55-62
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• 2021

하악은 상악보다 지지 면적이 적고, 특히 전반적인 치조골 흡수가 진행된 환자에서는 혀와 하악골의 움직임으로 인해 통상적인 총의치의 경우 의치의 안정성과 저작 효율이 현저히 낮다. 이러한 환자에 있어 소수의 임플란트를 이용한 임플란트 피개의치는 유지력과 안정성이 높고 발음이나 저작력 면에서도 우수한 예지성 있는 치료방법으로 평가되고 있다. 본 증례에서는 상악의 무치악, 하악의 전반적인 치조골 흡수를 보이는 환자에 있어 상악에는 총의치, 하악에는 4개의 임플란트를 식립하여 milled bar를 이용한 임플란트 피개의치를 제작하였다. 이후 12년 동안 임플란트 주변의 치주조직의 변화를 지속적으로 관리 및 관찰하였고, 변화 사항 및 보철물의 정기적인 관리에 대해서 보고하고자 한다.

• 대한치과보철학회지
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• 제35권1호
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• pp.95-102
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• 1997

Ameloblastoma is the most agrressive ofht odontogenic tumors and it arises from the dental lamina or the derivatives of lamina. Ameloblastoma is a benign but locally invasive neoplasm consisting of proliferating odontogenic epithelium lying in a fibrous stroma. Usually the ameloblastomas are diagnosed in the forth and fifth decardes. Over 80% of them occur in the mandible, the remainder in the maxilla. The preferred treatment for ameloblastoma is radical excision, conserving(when possible. the inferior border of the mandible. The functional and esthetic rehabilitation of the partially edentulous patient may prevent the remaining structures from supporting conventional prosthetic treatment. Patients with long edentulous spans, malpositioned teeth, residual ridges defects and high muscle attachments may be offered an osseointegrated fixed prosthesis. Osseointegrated dental implants provide a viable alternative of tooth replacement. This is a case report of 16 year old female with ameloblastoma. We treated patient with radical excision, conserving the inferior border of the mandible and allogenous bone graft. The defected residual ridge area was reconstructed implants(Steri-Oss Implant System). the result was satisfactory.

• 대한치과보철학회지
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• 제45권6호
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• pp.760-768
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• 2007

Statement of problem. Conventional denture treatment for totally edentulous patients is associated with a variety of functional and psychosocial problems. The placement of implants in the anterior region of the maxilla and mandible and the fabrication of an implant-retained overdenture might solve these problems. Purpose. This study compared the marginal bone loss around the implant and evaluated the implant survival rate and complications in patients treated with overdentures retained by implants for 2 years. Material and methods. Patients who had received implant-retained overdentures using a Dolder bar at Samsung Medical Center from January 1999 to June 2005 and had participated in the annual recall programs for two years were selected for this study. A total of 18 patients and 56 $Br{\aa}ne-mark\;system^{(R)}$ implants were used, and their data were reviewed. Evaluations of the survival rate, bone quality, marginal bone loss, and complications were performed. The data on the Dolder bar length and clip length were measured. The change in marginal bone loss and the correlation between the marginal bone loss and bar length, clip length, or bone quality were investigated. Results. Implants placed in this study showed a 100% survival rate. The average annual bone loss was 1.12mm in the first year and 0.27mm in the second year in the maxilla, and 0.58mm in the first year and 0.22mm in the second year in the mandible. The marginal bone loss in the maxilla showed no significant association with those in the mandible. (P>.05). There was no significant difference in marginal bone loss around implants between the first and second year. (P>.05) There was no statistically significant relationship (P>.05) between the marginal bone loss and bone quality, clip length, or Dolder bar length. The Dolder bar length showed a high correlation with the clip length. (P<.05) Various complications were noted. Conclusion. These results confirmed the favorable outcome for patients treated with implant-retained overdentures.