유약 영구 전치의 함입성 탈구에 관한 고찰과 치험례

전경현,김용기,김종수 大韓小兒齒科學會 1997 大韓小兒齒科學會誌 Vol.24 No.2

In the Pediatric Dentalc profession the occurrence rate intrusion of young permanent teeth is rather low, and the treatment method varies from one another. Intrusion of the teeth bring complications to the pulp and periodontal ligament, and thus the possibility of endodontic treatment increases. For the formation of calcific barriers, calcium hydroxide is used in young permanent teeth and this makes the final canal filling possible. In this case report, we will show two cases of young permanent teeth intrusion and the treatment methods to help assess the recognition of treatment for young permanent teeth intrusion.

분산처리 환경을 위한 효과적 오류수정에 관한 연구

전용기 慶尙大學校 1990 論文集 Vol.29 No.1

As a tool of the computation analysis which has done in either way of static or dynamic, the debugging sytem has been an important tool for a dynamic analysis through the actual executions of distributed computations. This paper discusses an approach to effective debugging aids for distributed computations through an event-based behavioral monitoring. With some assumptions of distributed debugging, it summerized primitive events which occurrs at the level of operating system kernel in a distributed computation. For the monitoring the bugs of distributed computations, a kernel facility and its interface are proposed, and integrated with a recognition subsystem which permits effective reasonings by behavioral abstraction approach.

유치와 영구치에 수복된 레진과 글라스 아이오노머 수복물의 미세누출 양상에 관한 비교연구

전경현,김종수,김용기 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.1

The purpose of this study was to compare the microleakage pattern of glass ionomer with resin restoration in microleakage pattern of primary and permanent teeth. Micreoscopical observation of interface between tooth structure and restoration was also performed. 80 and 8 sound molar teeth were used for the microleakage test and SEM study respectively. Data were analyzed statistically using ANOVA test and/or t-Test. The results of the present study were as follows: 1. According to the result of microleakage pattern between primary and permanent tooth, primary tooth generally showed more microleakage than permanent tooth in all groups(p<.05). 2. In the resin-filled groups, occlusal margin was shown to have more micreliakage than gingival margin(p<.05). Whereas the glass ionomer-filled groups showed no statestically significant differences between them(p>.05). 3. No statistically significant differences in microleakage could be found between two different resin groups(p>.05). while FujiⅡ LC group showed less microleakage than Ketac-Fil group(p>.05). 4. The various type hybrid layer was evident under SEM in resin-filled groups both in primary and permanent teeth with generally thicker layer in primary group. Among glass-ionomer group, FujiⅡ LC group showed more intact adhesion to tooth surface than Ketac-Fil group.

프로세스 수준의 추상에 의한 분산오류의 자동적 탐지기법

전용기 慶尙大學校 1990 論文集 Vol.29 No.2

The paper discuses a behavioral monitoring approach to effective debugging aids for distributed computations through an event-based automatic error detection. It investigates a debugging methodology for the approach and its relevant technique using behavior specifications and process-level abstrations. It describes the technique that behavior specifications dreven by users are automatically transformed and structured into the internal behavior representations which are then used as the global process-level abstraction against the inefficiency, the error latency, and the side effects that may be produced by the debugging procedure.

가시광선과 아르곤 레이저에 의한 복합레진 중합 효과의 비교 연구

전상언,김용기 大韓小兒齒科學會 1996 大韓小兒齒科學會誌 Vol.23 No.2

The purpose of this study was to evaluate the shear bond strengths,microhardness,compressive strength and contraction gap at the resin-tooth interface of two types of composite resins polymerized with visible light and argon laser sourse. The results from the present study can be summarized as follows: 1.Resin sample polymerized either by argon laser or visible light did not show significant difference in their physical properities tested(p>.05). 2.The contraction gap at the resin tooth interface was found to be present in all samples but any significant difference between groups could not be established due to their variability.Although the superiority of argon laser over visible light in enhancing the physical properities of resin could not be elucidated in the present study,continous efforts are deemed to be worthwhile to investigate this using different conditions and materials of experiment.

Mineral trioxide aggregate가 인간치수세포에서 유전자 발현에 미치는 영향

김용범,손원준,이우철,금기연,백승호,배광식 大韓齒科保存學會 2010 Restorative Dentistry & Endodontics Vol.35 No.3

이 연구에서는 mineral trioxide aggregate (MTA)를 in vitro로 인간치수세포에 적용하였을 때 유전자들의 변화를 조사하였다. 실험군은 MTA를 teflon tube (직경 10 mm 길이 2 mm)에 담아 4시간 경화시킨 후HDPCs에 적용하였고, 대조군은 빈 tub만을 적용하였다. 6, 24, 72시간 후 total RNA를 추출하여 microarray를 이용하여 분석하여, 2배 이상 또는 절반 이하의 변화를 보이는 유전자 중 선택적으로 역전사 중합효소 연쇄반응(reverse transcriptase polymerase chain reaction)을 사용하여 발현을 확인하였다. 24,546개의 유전자 중에서 109개의 유전자가 2배 이상 up-regulation되었으며(예. FOSB, THBS1, BHLHB2, EDN1, IL11, FN1, COL10A1, TUFT1) 69개의 유전자가 50%이하로 down-regulation되었다(예. SMAD6, DCN). MTA는 bio-inert한 재료라기 보다는 치수세포에 다양한 경로로 영향을 주는 재료로 사료된다. 특히 치수세포의 분화와 증식에 관여하는 유전자의 변화에 영향을 주며 석회화 과정에 관여하는 유전자의 변화에 직접적인 영향을 주리라 사료된다. This study investigated the changes in gene expression when mineral trioxide aggregate (MTA) was applied in vitro to human dental pulp cells (HDPCs). MTA in a teflon tube (diameter 10 mm, height 2mm) was applied to HDPCs. Empty tube-applied HDPCs were used as negative control. For microarray analysis, total RNA was extracted at 6, 24, and 72 hrs after MTA application. The results were confirmed selectively by performing reverse transcriptase polymerase chain reaction for genes that showed changes of more than two-fold or less than half. Of the 24,546 genes, 109 genes were up-regulated greater than twofold (e.g., FOSB, THBS1, BHLHB2, EDN1, IL11, FN1, COL10A1, and TUFT1) and 69 genes were downregulated below 50% (e.g., SMAD6 and DCN). These results suggest that MTA, rather than being a bioinert material, may have potential to affect the proliferation and differentiation of pulp cells in various ways.

감압증과 과폐압 사고

신용규,이상준,박영민,이인기 공군본부 의무감실 1991 항공의학 Vol.39 No.1-2

사춘기전 Ⅰ,Ⅱ급 부정교합 아동의 기도 면적, 혀의 위치와 안면 형태에 관한 연구

황용인,이규홍,이기준,김상철,조형준,천세환,박양호 대한치과교정학회 2008 대한치과교정학회지 Vol.38 No.2

본 연구는 사춘기 성장 이전의 I, II급 부정교합을 갖는 아동 환자들의 측모 두부 규격 방사선사진을 이용하여 두개 안면 형태를 조사하고 이들과 혀의 위치 및 면적, 기도의 면적과의 관계를 조사하여 비인두 기도 및 혀의 형태가 악골 및 부정 교합의 형태에 미치는 영향을 알아보았다. 9 - 11세의 교정환자 76명을 대상으로 측모 두부 규격 방사선사진상 ANB difference를 기준으로 대조군(I급 부정교합군: 0 ≤ ANB difference < 4.0)과 실험군(II급 부정교합군: ANB difference ≥ 4.0)으로 분류하였다. 혀 면적, 혀와 구개 사이의 면적, 비인두 기도 면적과 두개안면형태 항목을 측정하고 비교하여 다음과 같은 결과를 얻었다. 혀 면적, 혀와 구개 사이의 면적, 비인두 기도 면적은 II급 부정교합군과 I급 부정교합군 간에 유의한 차이를 보이지 않았다. Hyperdivergent안면 형태일수록 비인두 기도 면적이 좁았다. 안모의 전후방 수직 길이가 길수록 혀의 면적이 넓었고, 전안면 고경이 길수록 혀는 하방위치 하였다. 비인두기도 면적이 좁을수록 혀의 면적도 좁아졌다. 이상의 연구 결과 혀의 면적과 위치, 비인두 기도의 면적은 I급, II급 부정교합 간에 차이를 보이지 않으며 hyperdivergent 안면 형태 및 안모의 전후방 수직 길이와 관련이 있는 것으로 사료된다. Objective: This study examined the craniofacial morphology of young patients in their prepubertal stage showing class I, II malocclusion, by analyzing lateral cephalograms, and analyzed its relationship with tongue position, tongue space, and airway space in order to ascertain the effects of nasopharyngeal airway and tongue morphology on the form of the malocclusion. Methods: Seventy-six patients aging from 9 to 11 were divided into two groups depending on the ANB difference on the lateral cephalogram: Experimental grouP (CI II malocclusion group) showing 0 ≤ ANB difference < 4.0; Control group (CI I malocclusion group) showing 0 ≤ ANB difference < 4.0. The tongue space, space between palate and tongue, nasopharyngeal airway space and craniofacial morphology were compared between the two groups. Results: Tongue space, Palate-tongue space, nasopharyngeal airway space showed no significant differences between class I and class II malocclusion groups. Hyperdivergent faces were associated with smaller nasopharyngeal airway space. Longer anterior facial height and posterior facial height were associated with larger tongue space, and greater anterior facial height were associated with lower tongue position, Smaller nasopharyngeal airway space showed smaller tongue space. Conclusions: Tongue space and nasopharyngeal airway space showed no significant differences between class I malocclusion group and class II malocclusion group. Only anterior facial height and posterior facial height had an influence on tongue space and nasopharyngeal airway space.

상실된 영구 중절치의 교정적 치료와 심미적 수복 치험례

김용기,전상언 大韓小兒齒科學會 1994 大韓小兒齒科學會誌 Vol.21 No.2

A major cause of missing permanent incisors is congenital abscence and extraction because of trauma and pathologic condition. The request for restoration of missing or spaced anterior teeth is common in dental practice. Problems, such as the tilting, drifting, and rotation of teeth adjacent to the space, complicate the restoration of apperance, and a normally simple restorative dental procedure may become difficult. There are two primary treatment alternatives to improving a dentition's irregular and spaced apperance-closing the space by orthodontic means or providing a prosthesis to disguise the space. The treatment choice depends on many variables, but, as a general rule, patients with a normal overbite, overjet, and buccal relationship are better treated by maintaining the space and providing a prosthesis, either fixed or removable. This case report presents two cases : Traumatic loss of maxillary right and left central incisors, Extraction of malformed mandibular right central inciosr. The loss of central incisor space was regained by the fixed-removable and fixed orthodontic appliance, and then Mary-land bridge was cemented.

세마포아 연산을 포함한 병렬 프로그램의 오류수정을 위한 추적 화일 분석

김동국,전용기 慶尙大學校 1992 論文集 Vol.31 No.2

Parallel programs may show errors generated by incorrect interactions between concurrintly executing processes, as well as logical ones which are similar to in sequential programs. Specifically, it shows nondeterministic executions by races for shared variables during program executions with anonymous synchronizations. To analyze the races, we can obtain the safe orders which are deterministic execution orders through observing the partical orders of events in a sequential trace. The main goal of the paper is an implemintation of the algorithms which determine a set of the safe orders in a given trace file.