• Journal of Oral Medicine and Pain
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• 제23권2호
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• pp.193-209
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• 1998

In identifying bodies that are severely decayed or damaged, methods using fingerprints and various biochemical tests are known to have its limits. To overcome this, forensic odontological method which is based on the analysis of the cranium, tooth and dental restoration is used to enhance the accuracey of individual identification. For this reason, I have come to analysis of the dental materials that exists between the teeth that is perceived to have been previously restored and the one adjacent to it. By analyzing the constituents of gold crown-restored, non-precious metal-restored, gold inlay-restored and amalgam -restored teeth, and adjacent teeth using EDX(energy dispersive X-ray microanalysis) which was invented to analyze very small amount of elements, the nature of the restoration could be predicted and the results obtained were as follows. 1. Some of constitute of gold alloy was extracted from residual cement of gold crown restoration, but that was not extracted from the restored tooth and the one adjacent to it. 2. Some of constituents of non-precious metal alloy was extracted both in the residual cement on the tooth with no-precious metal restoration and in the tooth with the restoration itself. However, none of its constituents were found in the tooth adjacent to it. 3. Some of constituents of gold alloy were found in the residual cement of gold inlay, but they were not found in the restored tooth and the adjacent tooth. 4. Some of constituents of amalgam alloy were found both in tooth restored with amalgam and in the adjacent tooth. From the results obtained above, it is possible to utilize the data obtained from analyizing residual dental materials in a more effective way. This data compensates for the lost data due to any harm done to the restorations prior to individual identification and further enhances the accuracy. Therefore, it could be concluded that this process of analyzing residual dental materials could be beneficial to individual identification in the area of forensic odontoldogy.

• 대한소아치과학회지
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• 제24권4호
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• pp.781-787
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• 1997

In spite of the improvements of the techniques in the field of preventive dentistry, many children still present with extensive destruction of primary anterior teeth. Not only the practioner must consider the pulp state of the primary incisor, but also restore the form, function and esthetics of the tooth. Restorative treatment of primary incisor tooth requires durability, retention and esthetics. Stainless steel crowns used in restoring primary anterior teeth is retentive and durable in comparison with the composite resin, celluloid crown. But they are not esthetic. To enhance the esthetics of the anterior stainless steel crown without reducing its superior retention, an open-face stainless steel crown has been suggested. Several authors have suggested cutting away the labial portion of the stainless steel crown and placing the composite resin in that area. By following this technique, the practioner can prepare a retentive, durable, and esthetic restoration for primary teeth which have suffered from extensive loss of teeth structure. In addition, the single missing primary anterior teeth can be successfully restored by soldering the stainless steel crown together. Open-face stainless steel crown is indicated in the areas of large interproximal lesions involving incisal edge, crown fracture with pulp exposure and congenital malformation of the teeth. By this technique, the practioner can restore primary anterior teeth successfully regardless of the amount of remaining tooth structure, bruxism habit and presence of attrition. In this case, rampant caries with extensive loss of tooth structure and single missing of primary anterior tooth hart been successfully treated with open-face stainless steel crown.

• 한국환경복원기술학회지
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• 제15권3호
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• pp.45-54
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• 2012

This study intended to analyze growth condition of each object by protected tree's ground for 45 places registered to Pyeongtaek protected tree list in locational characteristics, conduct exchange analysis for impediment extent rate in crown area and tree type to the result and suggest the measures to manage artificial impediment which is an effect on protected tree condition. In this study, the tree whose area of impediment for crown area is less than 21% is tree condition of grade 1~2, less than 21~50% is grade 2~3 and more than 50% is grade 3~5. The more impediment is, the more inconvenience causes on growth and development. So, it verified that the area rate must maintain less than 21% for the root system management of protected tree. For the standard of managing artificial impediment which is an effect on the tree condition of protected trees, the below matters intend to be suggested. The first, the impediment in crown area should be less than 21%. But, if there is not artificial impediment out of crown area, the rate of impediment area is considered to increase somewhat. The second, growth space of protected tree should be maintained by crown area at least and impediment should be established out of the crown area. The third, during the national project and land development, surroundings of protected tree must be applied as park, resting place, etc. and the establishment area of impediment (artificial impediment and natural impediment) in crown area must be limited. The forth, publicity for regional people (especially, land owner) is necessary for the protection of natural inheritance and the value of dependence on local government and village which are the subject of management must be announced widely through the internet media, etc, so its importance must be recognized. The fifth, the matters related to protected tree management must be able to limit artificial damage which is for surroundings of protected tree through the mutual connection among the local governments; construction, civil engineering, architecture, water and sewage, agriculture and forest and others. Also, following studies on the effects of kinds, thickness, etc. of impediment around the protected tree on trees should be continued.

• 대한소아치과학회지
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• 제39권1호
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• pp.58-65
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• 2012

치관-치근 파절은 법랑질, 상아질, 백악질이 모두 포함된 치아의 파절로, 파절선이 대부분 절단연이나 순측의 변연부 치은에서 구개측 치은열구 하방으로 사선으로 진행된다. 파절선의 위치가 치은 연상이라면 파절편의 제거 및 치은연상 수복을 시행하고, 치은 연하라면 파절면의 외과적 노출술, 교정적 정출술, 외과적 정출술을 이용한 치아의 수복이 이루어진다. 그 외에 섬유 강화형 포스트를 삽입하여 치관 수복물의 유지력을 높이고, 레진 접착 시스템을 사용하여 치관 파절편을 재부착함으로써 생물학적으로 최소한으로 침습적인 치료를 하는 방법도 있다. 만약 파절의 정도가 치은 연하로 깊은 경우 발치나 치관절제술을 이용한 치근의 유지 등을 고려할 수 있다. 본 증례는 치관-치근파절로 내원한 12세 환아로 섬유강화형 포스트를 사용하여 치관 파절편 재부착을 시행하였으며 양호한 경과를 보여 이를 보고하는 바이다.

• 대한소아치과학회지
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• 제50권1호
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• pp.104-112
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• 2023

3D 프린터로 출력된 레진 크라운은 유치의 심미 수복을 위한 크라운으로 사용될 수 있으며, 접착에는 주로 레진 시멘트가 사용된다. 본 연구의 목적은 크라운 제작용 3D 프린팅 레진의 접착 능력을 평가하고, 이를 다른 레진 간접 수복용 재료들과 비교하는 것이었다. 3D 프린팅 레진인 Graphy (GP)와 NextDent (NXT), 레진 간접 수복용 재료인 MAZIC Duro (MZ)와 VIPI Block (VIPI)의 전단결합강도가 본 연구에서 비교되었다. GP, NXT, MZ, VIPI군의 평균 전단결합강도는 각각 23.29 ± 3.88, 26.14 ± 4.67, 25.41 ± 4.03, 18.79 ± 4.26 MPa였다. VIPI군을 제외한 GP, NXT, MZ군의 평균 전단결합강도 값에는 유의미한 차이가 없었다. 본 연구 결과 3D 프린팅 레진은 레진 시멘트와 임상적으로 허용 가능한 수준의 접착 강도를 나타냈으며, 이에 따라 유치 수복을 위한 크라운 재료로서 적합한 조건을 갖추고 있음을 확인하였다.

• 대한소아치과학회지
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• 제43권1호
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• pp.60-69
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• 2016

영구 전치의 복합 치관-치근 파절은 심미적, 기능적 문제 뿐 아니라 심리적 문제도 발생시킨다. 그러므로 파절에 대한 치료는 매우 중요하며, 여러 분야에 걸친 종합적 치료가 요구된다. 본 증례는 두 환자에서의 외상으로 인한 상악 전치의 복합 치관-치근 파절에 대한 임상적 치료 과정을 서술하였다. 근관치료와 근첨형성술이 각 환자에게 시행되었으며, 파절선을 치은 상방으로 노출시키고 생물학적 폭경을 재확립하기 위해 교정적 정출을 시행하였다. 이후 유지기간을 두었고, 그 기간 동안 치아에 임시수복을 시행하였다. 최종적으로 CAD/CAM을 이용한 세라믹 크라운 수복을 시행하였다. 이후 정기 검진 때에도 해당 치아들은 만족스러운 기능적, 심미적 결과를 보였으며, 두 환자 모두에서 재발은 나타나지 않았다. 치주조직 또한 건강한 상태를 보였다.

• 구강회복응용과학지
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• 제34권4호
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• pp.317-323
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• 2018

구강암이 상악에 발생하게 되면 원발 부위의 제거를 포함한 외과적 처치 후 비구강 개통(oro-nasal communication)이 발생하게 된다. 비구강 개통으로 인한 음식물의 저류를 막고 및 원할한 발음 및 심미적 회복을 위해서는 구강 폐색장치(Obturator)를 통한 수복이 필요하다.본 증례에서는 구강암으로 인해 우측 상악 편측절제술(hemi-maxillectomy) 시행하고 두경부 방사선 치료의 영향으로 인해 잔존 지대치의 우식과 불량한 치주지지를 보이는 환자에서 구강폐색장치(obturator)를 하이브리드형 이중관의치(hybrid telescopic double crown denture)로 수복하였다. 18개월 간 경과관찰에서 성공적인 예후를 보여 이를 보고하고자 한다.

• The Journal of Advanced Prosthodontics
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• 제16권2호
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• pp.77-90
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• 2024

PURPOSE. The study aims to investigate the influence of the ferrule effect and types of posts on the stress distribution in three morphological types of the maxillary central incisor. MATERIALS AND METHODS. Nine models were created for 3 maxillary central incisor morphology types: "Fat" type - crown 12.5 mm, root 13 mm, and buccolingual cervical diameter 7.5 mm, "Medium" type - crown 11 mm, root 14 mm, and buccolingual cervical diameter 6.5 mm, and "Slim" type - crown 9.5 mm, root 15 mm, and buccolingual cervical diameter 5.5 mm. Each model received an anatomical castable post-and-core or glass-fiber post with resin composite core and three ferrule heights (nonexistent, 1 mm, and 2 mm). Then, a load of 14 N was applied at the cingulum with a 45° slope to the long axis of the tooth. The Maximum Principal Stress and the Minimum Principal Stress were calculated in the root dentin, crown, and core. RESULTS. Higher tensile and compression stress values were observed in root dentin using the metallic post compared to the fiber post, being higher in the slim type maxillary central incisor than in the medium and fat types. Concerning the three anatomical types of maxillary central incisors, the slim type without ferrule height in mm presented the highest tensile stress in the dentin, for both types of metal and fiber posts. CONCLUSION. Post system and tooth morphology were able to modify the biomechanical response of restored endodontically-treated incisors, showing the importance of personalized dental treatment for each case.

• 대한소아치과학회지
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• 제25권4호
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• pp.717-730
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• 1998

The Finite Element Analysis has been used for stress analysis of prosthesis, orthodontic or orthopedic appliances and filling materials. The primary purpose of the present studying was to evaluate the effectiveness of needle post in promoting the retention and integrity of composite crown restored on the pulpotomized primary central incisor. Three finite element models-natural tooth (Sample I), composite crown with (Sample II) and without (Sample III) needle post-were constructed and the stress distribution within each model were analyzed and compared one another. The results can be summarized as follows: 1. In sample I, the stress was shown to have distributed uniformly throughout the whole tooth even to the alveolar bone. 2. In sample II, the transmission of stress from the crown to the root area was shown to be very poor and irregular. 3. In sample III, the needle post was proved to be very effective in distributing the stress well to the aveolar bone which might help in maintaining the stability of crown restoration.

• Restorative Dentistry and Endodontics
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• 제8권1호
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• pp.53-59
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• 1982

An in vitro study was performed in order to evaluate the restoring methods in the endodontically treated molar teeth. 68 extracted teeth were divided into 4 groups according to the restoring techniques. The teeth of first group were restored by amalgam. Those of second group were restored by the stainless steel post and amalgam. The teeth of the third group were restored by the amalgam with crown. The teeth of the fourth group were restored by the stainless steel post and amalgam core with crown. All the specimens were tested and measured for the fracture load by means of the Instron (UTM-111-500 Toyo Baldwin Co., LTD. Japan) and the Pressure Instrument (Yonsei University, Department of Metal Engineering.) The results were as follows; 1. There were no statistical differences in the fracture loads between the amalgam restoration and post-amalgam core restorative techniques. 2. The techniques of amalgam core with crown showed lower fracture loads those of post and amalgam core with crown. 3. In the crowned teeth, they presented higher fracture loads than those without crown.