• 대한소아치과학회지
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• 제32권1호
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• pp.18-25
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• 2005

외상성 골낭(Traumatic Bone Cyst)은 상피이장이 없는 비치성낭으로 감염의 증거가 없으며 많은 액체가 내장되는 특징을 가지는 병소이다. 외상성 골낭은 자각증상이 없는 병소로 10대에서 20대 사이에 호발하며 주로 남자에서 호발한다. 병소는 방사선학적으로 조개껍질 모양의 명확한 경계를 가지며 방사선 투과상을 보인다. 병소는 해면골에 위치하며 간혹 치밀골을 팽창시키거나 비박화시킨다. 병소 주변의 치아는 생활력을 유지하는 특징이 있다. 일반적으로 외상성 골낭은 방사선학적, 임상적인 기준으로 진단을 내리게 된다. 외상성 골낭의 치료법은 일반적으로 외과적인 적출술과 소파술을 시행한다. 본 두 증례 중 첫 번째 증례에서 환아는 개인치과의원에서 치수치료 도중 방사선 사진에서 방사선 투과상이 발견되어 본원으로 의뢰되었으며 파노라마 방사선 사진촬영 결과 좌측 하악골에 명확한 경계를 보이는 방사선 투과상을 보였다. 두 번째 증례에서 환아는 치외치인 상악 우측 제2소구치의 농양을 동반한 종창을 주소로 내원하였다가 초진시 촬영한 파노라마 방사선 사진에서 우측 하악골에 명확한 경계의 방사선 투과상을 보였다. 두 증례 모두 임상적, 방사선학적 검사결과 외상성 골낭으로 진단받았다. 첫 번째 증례에서는 생활력을 상실한 인접치아의 치근단공에 과기구 조작을 시행하여 병소를 교통시킨 후 지속적인 세척을 시도하여 병소가 치유되는 양상을 보였고, 두 번째 증례에서는 아무런 처치 없이 지속적인 관찰결과 병소의 크기가 감소하는 양상을 보였다. 본 두 증례에서 외과적인 적출술과 소파술을 시행하지 않고 보존적인 처치를 하였음에도 병소가 치유양상을 보이기에 보고하는 바이다.

• 대한치과보철학회지
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• 제32권2호
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• pp.327-353
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• 1994

This study was performed to evaluate the effects of number and alignment of implant fixture and various bar designs on the retention of denture and the stress distribution. Six kinds of photoelastic mandibular models and nine kinds of overdenture specimens were designed. A unilateral vertical load was gradually applied on the right first molar to calculate the maximal dislodgement load of each specimen. A unilateral vertical load of 17 Kgf was applied on the right first molar and a vertical load of 10 Kgf was applied on the interincisal edge region. The stress pattern which developed in each photoelastic model was analyzed by the reflection polariscope. The results obtained were as follows: 1. The maximal dislodgement load reversely increased with the distance from the loading point to the implant fixture, while it linearly increased with that from the most posterior implant fixture to the mesial clip. The maximal dislodgement load also increased with the use of a cantilever bar. 2. Under the posterior vertical load, the stress to the supporting tissue of the denture base increased with the distance from the loading point to the implant future. The stress concentration on the apical area of the implant future reversely increased with the distance from the loading point to the implant future. 3. In the overdentures supported by two implant fixtures under the posterior vertical load. the specimen implanted on lateral incisor areas with a cantilever bar exhibited more favorable stress distribution than that without a cantilever bar. The specimen implanted on the canine areas without a cantilever bar, however, exhibited more favorable stress distribution. 4. In the overdentures supported by three implant fixtures. the specimen implanted ell the midline and canine areas exhibited more favorable stress distribution than that implanted oil the midline and the first premolar areas. 5. In the overdentures supported by four implant fixtures. the specimen implanted with two adjacent implant fixtures exhibited more favorable stress distribution than that implanted at equal distance under the posterior vertical load. 6. Under the anterior vertical load, the overdentures supported by three implant fixtures exhibited stress concentration on the supporting structure of the middle implant future. In overdentures supported by two or four implant futures, no significant difference was noted in stress distribution between the types of bars. These results indicate that the greater the number of implant fixtures, the better the stress distribution is. A favorable stress distribution may be obtained in the overdentures supported by two or three implant fixtures, if the location and the design of the bar are appropriate.

• 대한소아치과학회지
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• 제50권2호
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• pp.179-191
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• 2023

이 연구의 목적은 2010년 1월부터 2021년 2월까지 부산대학교 치과병원에 내원한 8 - 16세 환자를 대상으로 영구치의 선천성 치아 결손 유병률 및 결손 유형을 조사하는 것이다. 총 11,759명(여성 5,548명, 남성 6,211명)의 파노라마 방사선 사진과 전자의무기록을 후향적으로 분석하였다. 선천 결손 유병률은 10.74%였다(여성 11.95%, 남성 9.66%, p < 0.0001). 평균 2.22개의 치아가 결손이 되었으며, 하악(8.39%)의 치아가 결손이 된 경우가 상악(4.52%)에 비해 많았다(p < 0.0001). 가장 빈번하게 결손이 되는 치아는 하악 제2소구치(58.19%)였다. 모든 분악에서 1개의 치아가 결손이 된 경우는 제2소구치가(30.10%, 31.67%, 43.14%, 35.59%), 2개 이상의 치아가 결손이 된 경우는 제1, 2소구치가(11.69%, 11.47%, 5.94%, 5.24%) 가장 많았다. 악궁 간 관계와 전악에서 결손 유형의 1 - 4위는 모두 제1, 2소구치가 연관이 되어 있었다. 이 연구 결과는 선천적 치아 결손 환자의 치료 계획 설립에 임상적 보탬이 될 수 있으며 특정 유전자와의 연관성을 밝혀내기 위한 분자생물학적 연구의 기초자료로 활용될 수 있을 것이다.

• 대한치과보철학회지
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• 제47권2호
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• pp.206-214
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• 2009

연구목적: 하악 우측 제1, 2 대구치가 결손된 Kennedy 분류 II급 증례에서 임상적으로 적용할 수 있는 편측 유리단 가철성 국소의치의 종류에 따른 응력 분포 양상을 비교하는 것이다. 연구 재료 및 방법: Kennedy 분류 II급 증례의 광탄성 모형에서 클라스프를 이용한 국소의치, 코너스 치관을 이용한 국소의치, 완압형 어태치먼트를 이용한 국소의치, 탄성 레진을 이용한 국소의치를 편측성으로 제작하였다. 응력 동결로에서 응력 주기에 맞춰 각 국소의치의 제1 대구치 중심와에 6 kg의 수직하중을 가하면서 응력을 동결하였다. 광탄성 모형을 절단하여 만든 시편을 광탄성 실험 장치로 광탄성 등색선의 흑백 무늬를 관찰하고 디지털 카메라로 촬영하였다. 촬영된 사진에서 8개의 측정점을 정하여 육안으로 무늬차수를 계측하고 비교하였다. 결과: 각 절단 시편의 최대 무늬차수와 하중점 직하방의 잔존 치조제에 발생한 무늬차수는 탄성 레진을 이용한 국소의치, 클라스프를 이용한 국소의치, 완압형 어태치먼트를 이용한 국소의치, 코너스 치관을 이용한 국소의치 순으로 높게 관찰되었다. 제2 소구치 치근단에 발생한 무늬차수는 클라스프를 이용한 국소의치, 탄성 레진을 이용한 국소의치, 코너스 치관을 이용한 국소의치, 완압형 어태치먼트를 이용한 국소의치 순으로 높게 관찰되었다. 결론: 코너스 치관을 이용한 국소의치가 수직하중시 지대치 주위 치조골과 잔존 치조제에 대하여 응력을 가장 균형있게 분산시켰고, 탄성 레진을 이용한 국소의치는 지대치보다 잔존 치조제의 상태가 더 양호한 경우에 적용 가능할 것이다.

• 대한치과교정학회지
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• 제32권6호
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• pp.435-441
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• 2002

교정치료의 고정원으로서 수술용 Microscrew가 소개되고 사용되어 왔다. 몇몇 임상가들은 Miniscrew혹은 Microscrew를 치근의 손상을 피하기 위하여 치근 하방의 기저골에 식립하여 사용하여 왔다 그러나 저자는 Microimplant를 치근 손상없이 치근사이의 치조골에 식립하여 고정원으로 사용하여 왔다. 이렇게 하므로서 치근하방에 식립할때 생기는 문제점인 수직 분력이 커지고 수평 분력이 작아지는 것을 방지하여 상악의 경우 적절한 후상방 교정력을 가할 수 있다 그리고 치조골에 상악의 경우 치아 장축에 대하여 30-40도의 각도로, 하악의 경우 10-20도의 각도로 식립하여 교정력의 방향을 전술한 바와 같이 수평방향으로 바꾸고 긴 Micro-implant를 치근 손상의 위험성을 줄이며 식립하여 안정도를 높일 수 있었다. 그러나 Mciro-implant를 치근사이 치조골에 식립하는데 기준이 되는 어떠한 연구도 이루어 지지 않았다. 본 연구는 Micro-implant식립에 기준이 되는 즉 치근 손상 없이 비교적 안전하게 식립할 수 있는 부위의 선택을 위한 근거 자료를 얻기 위하여 시행되었다. 21명 환자를 대상으로 치조골로부터 5-7mm에 해당하는 CT 절단면을 선택하여 피질골의 두께, 피질골 표면과 치근과의 거리, 치근사이의 거리등을 측정하였다. 각 부위별 피질골의 두께, 골 표면과 치근사이의 거리, 인접 치근사이의 거리등을 구하였다. .피질골의 두께는 전치부에서 구치부로 이행할수록 두꺼웠다. 특히 하악골 구치부에서 가장 두꺼웠다. 인접 치근 사이의 거리 계측 항목에서 상악에서는 제2소구치와 제 1대구치사이, 하악에서는 제 1대구치와 제 2대구치 사이에서 가장 큰 값을 보였다.

• 대한치과교정학회지
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• 제34권4호
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• pp.289-301
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• 2004

It is the purpose of this study to characterize oral symptoms and to comprehend the cause and the relapse possibility of patients with open bite. This case study examines the orthodontic treatment of a group of female patients with open bite and Angle's Class I malocclusion. A cephalograph of the patient was taken and tracing of the radiograph was completed. In addition to Bjork and Ricketts analysis, additional measurements of specific areas were taken. The occlusal plane was determined by drawing a line connecting the mesiobuccal cusp tip of the maxillary first molar and the incisal edge of the maxillary central incisors. Patients were divided into two groups depending on the relationship between the marginal ridge of the maxillayy first premolar and the drawn line. Those patients with marginal ridges above the occlusal plane were placed into Group 1, while Group 2 subjects exhibited marginal ridges lower than the occlusal plane. The common characteristics within each group and the characteristic differences between each group both prior to and after orthodontic treatment were examined, and finally, the functional oral volume of each patient was analyzed. The results of the case study were as follows: 1. An examination of the skeletal relationship and anatomical form for both Group 1 and 2 showed that all subjects exhibited hyperdivergent skeletal forms, but Group 2 subjects generally demonstrated underdevelopment of the mandible and a smaller articular angle, resulting in an anterior positioning tendency of the mandible. 2. An analysis of the maxillary arches of Group 1 subjects prior to and after orthodontic treatment showed that the antero-inferior direction had changed to an antero-superior directional tendency, while the maxillary arches of the Group 2 patients showed a trend from an antero-superior direction to an antero-inferior relationship. The mandibular arches in both groups showed a change to an antero-superior direction. 3. Functional space analysis showed that Group 2 patients exhibited a greater tendency of haying palatal planes that drop in a postero-inferior direction, resulting in a more severe open bite than their Group 1 counterparts. The results of this case study show that although patients belonging to either Group 1 or 2 exhibited few external differences in the appearance of open bite, an examination of the dental and skeletal relationships by analyzing patient cephalographs showed that patients presenting with flat maxillary occlusal planes exhibited more severe open bite relationships than patients with curved occlusal planes.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제41권
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• pp.27.1-27.9
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• 2019

Background: Implants are becoming the first choice of rehabilitation for tooth loss. Even though they have a high success rate, failures still occur for many reasons. The objective of this study is to analyze the reasons for recurring failure at the same site and the results of re-implantation. Methods: Thirteen patients (11 males and 2 females, mean age 60 ± 9.9 years) who experienced implant surgery failure at the same site (same tooth extraction area) two or more times in the Department of Oral and Maxillofacial Surgery, Seoul National University Bundang Hospital, between 2004 and 2017 were selected. The medical records on a type, sites, diameter, and length of implants; time and estimated cause of failure; and radiographs were reviewed. Data were collected and analyzed retrospectively, and the current statuses were evaluated. Results: A total of 14 implants experienced failure in the same site more than two times. Twelve implants were placed in the maxilla, while 2 implants were placed in the mandible. The maxillary molar area was the most common site of failure (57.1%), followed by the mandibular molar, anterior maxilla, and premolar areas (14.3% each). The first failure occurred most commonly after prosthetic treatment (35.7%) with an average period of failure of 3.8 months after loading. Ten cases were treated as immediate re-implantation, while the other 4 were delayed reimplantation after an average of 3.9 months. The second failure occurred most commonly after prosthetic treatment (42.9%), with an average of 31 months after loading; during the healing period (42.9%); and during the ongoing prosthetic period (14.3%). In 3 cases (21.4%), the treatment plan was altered to an implant bridge, while the other 11 cases underwent another implant placement procedure (78.6%). Finally, a total of 9 implants (64.3%) survived, with an average functioning period of 60 months. Conclusions: Implants can fail repeatedly at the same site due to overloading, infection, and other unspecified reasons. The age and sex of the patient and the location of implant placement seem to be associated with recurring failure. Type of implant, bone augmentation, and bone materials used are less relevant.

• Journal of Periodontal and Implant Science
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• 제26권1호
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• pp.1-26
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• 1996

This study was performed to estimate the effects of cultured bone cell inoculated on porous type hydroxyaptite for the regeneration of the artificial alveolar bone defect. In this experiment 3 beagle dogs were used, and each of them were divided into right and left mandible. Every surgical intervention were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium(30mg/Kg). To reduce the gingival bleeding during surgery, operative site was injected with Lidocaine hydrochloride(l:80,000 Epinephrine) as local anesthesia. After surgery experimental animal were feeded with soft dietl Mighty dog, Frisies Co., U.S.A.) for 1 weeks to avoid irritaion to soft tissue by food. 2 months before surgery both side of mandibular 1st premolar were extracted and bone chips from mandibular body were obtained from all animals. Bone cells were cultured from bone chips obtained from mandible with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. Porous type hydroxyapatite were immerse into the high concentrated cell suspension solution, and put 4 hours for attachin the cells on the surface of hydroxyapatite. Graft material were inserted on the artificial bone defect after 3 days of culture. Before insertion of cellinoculated graft material, scanning electronic microscopic observation were performed to confirm the attachment and spreading of cell on the hydroxyapatite surface. 3 artificial bone defects were made with bone trephine drill on the both side of mandible of the experimental animal. First defect was designed without insertion of graft material as negative control, second was filled with porous replamineform hydroxyapatite inoculated with cultured bone marrow cells as expermiental site, and third was filled with graft materials only as positive control. The size of every artificial bone defect was 3mm in diameter and 3mm in depth. After the every surgical intervention of animals, oral hygiene program were performed with 1.0% chlorhexidine digluconate. All of the animals were sacrificed at 2, 4, 6 weeks after surgery. For obtaining histological section, tissus were fixed in 10% Buffered formalin and decalcified with Planko - Rycho Solution for 72hr. Tissue embeding was performed in paraffin and cut parallel to the surface of mandibular body. Section in 8um thickness of tissue was done and stained with Hematoxylin - Eosin. All the specimens were observed under the light microscopy. The following results were obtained : 1. In the case of control site which has no graft material, less inflammatory cell infiltration and rapid new bone forming tendency were revealed compared with experimental groups. But bone surface were observed depression pattern on defect area because of soft tissue invasion into the artificial bone defect during the experimental period. 2. In the porous hydroxyapatite only group, inflammatory cell infiltration was prominet and dense connective tissue were encapsulated around grafted materials. osteoblastic activity in the early stage after surgery was low to compared with grafted with bone cells. 3. In the case of porous hydroxyapatite inoculated with bone cell, less inflammatory cell infiltration and rapid new bone formation activity was revealed than hydroxyapatite only group. Active new bone formation were observed in the early stage of control group. 4. The origin of new bone forming was revealed not from the center of defected area but from the surface of preexisting bony wall on every specimen. 5. In this experiment, osteoclastic cell was not found around grafted materials, and fibrovascular invasion into regions with no noticeable foreign body reaction. Conclusively, the cultured bone cell inoculated onto the porous hydroxyapatite may have an important role of regeneration of artificial bone defects of alveolar bone.

• The Journal of Advanced Prosthodontics
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• 제9권5호
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• pp.341-349
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• 2017

PURPOSE. This study evaluated the accuracies of different bite registration techniques for implant-fixed prostheses using three dimensional file analysis. MATERIALS AND METHODS. Implant fixtures were placed on the mandibular right second premolar, and the first and second molar in a polyurethane model. Aluwax (A), Pattern Resin (P), and Blu-Mousse (B) were used as the bite registration materials on the healing abutments (H) or temporary abutments (T). The groups were classified into HA, HP, HB, TA, TP, and TB according to each combination. The group using the bite impression coping was the BC group; impression taking and bite registration were performed simultaneously. After impression and bite taking, the scan bodies were connected to the lab analogs of the casts. These casts were scanned using a model scanner. The distances between two reference points in three-dimensional files were measured in each group. One-way ANOVA and Duncan's test were used at the 5% significance level. RESULTS. The smallest distance discrepancy was observed in the TB group using the temporary abutments. The Blu-Mousse and HP groups showed the largest distance discrepancy. The TB and BC groups showed a lower distance discrepancy than the HP group (P=.001), and there was no significant difference between the groups using the temporary abutments and healing abutments (P>.05). CONCLUSION. Although this study has limitations as an in-vitro investigation, the groups using the temporary abutments to hold the Blu-Mousse record and bite impression coping showed greater accuracy than the group using the healing abutments to hold the pattern resin record.

• 대한치과교정학회지
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• 제28권3호
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• pp.343-351
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• 1998

본 연구는 비발치로 치료된 I급 부정교합 환자의 형태적 특성을 알아보고자 시행하였다. 비발치로 치료된 I급 부정교합 환자의 치료전과 치료후 안면형태를 평가하고 이를 교정치료를 받지 않은 정상군과 4개의 제 1소구치를 발거하고 치료한 I 급 부정교합 환자군과 비교하였다. Edgewise appliance와 MEAW를 사용하여 비발치로 치료한 환자로 치료후 비교적 양호한 안모와 교합을 갖는 환자 22명을 대상으로 하였다. 이들의 평균 연령은 14.7세 였고 평균 치료기간은 2.6년이었다 치료전과 치료후의 두부계측방사선 사진에서 32개의 계측점을 사용하여 24항목의 각도와 거리를 측정하였다. Student t-test를 시행하여 비발치군의 치료전과 치료후의 변화, 비발치군과 정상군의 차이, 그리고 비발치군과 발치군의 차이를 비교한 결과($p{\leq}0.05$), 다음의 결론을 얻었다. 1. 비발치로 치료한 I 급 부정교합 환자의 치료전 ODI는 $69.9^{\circ}$, APDI는 $82.1^{\circ}$, CF는$152^{\circ}$, EI는 $152^{\circ}$ 였다. 2. 비발치군의 골격형태는 정상군과 유사하였으나 정상군보다 큰 절치간각을 보였다. 3. 발치군은 비발치군보다 돌출된 안모와 작은 절치간각, 그리고 낮은 EI를 가지고 있었다. 4. 비발치군의 치료전,후 골격형태에는 큰 변화가 없었으나 치료후 상,하악 구치의 직립과 절치간각의 감소를 나타내었다.