• 제목/요약/키워드: divided difference of order one-two

검색결과 83건 처리시간 0.029초

산부식후 상아질 표면의 습윤 또는 건조가 상아질 결합에 미치는 영향 (EFFECTS OF DENTIN SURFACE WETNESS OR DESICCATION AFTER ACID ETCHING ON DENTIN BONDING)

  • 양원경;권혁춘;손호현
    • Restorative Dentistry and Endodontics
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    • 제25권2호
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    • pp.243-253
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    • 2000
  • The purpose of this in vitro study was to evaluate dentin bonding by two different dentin bonding systems(DBS) using acetone based primer or adhesive [All Bond 2(AB2), One Step(OS)] when they were applied by wet or dry bonding technique. Morphology of resin-dentin interface and hybrid layer thickness(HLT) were investigated using Confocal Laser Scanning Microscope(CLSM) and compared to shear bond strength(SBS). 72 extracted sound human molars were randomly divided into 4 groups of 18 teeth each - Group 1.(AW); AB2 by wet bonding. Group 2(AD); AB2 by dry bonding. Group 3.(OW); OS by wet bonding, Group 4.(OD); OS by dry bonding. In 6 teeth of each group, notch-shaped class V cavities(depth 2mm) were prepared on buccal and lingual surface at the cementoenamel juction(12 cavities per group). To obtain color contrast in CLSM observation, bonding resins of each DBS were mixed with rhodamine B and primer of AB2 was mixed with sodium fluorescein. Prepared teeth of each group were treated with AB2, OS, respectively according to the manufacturer's instructions except for dentin surface moisture treatment after acid etching. In group 1 and 3, after acid etching, excess water was removed with wet tissue(Kimwipes), leaving consistently shiny, visibly hydrated dentin surface. In group 2 and 4, dentin surface was dried for 10 seconds at 1 inch distance. The treated teeth were then packed with composite resin(${\AE}$litefil) and light-cured. 12 microscopic samples($60{\sim}80{\mu}m$ thickness) of each group were obtained after longitudinal section and grinding(Exakt cutting and grinding system). Morphological investigation of resin-dentin interface and HLT measurement using CLSM were done. For measurement of SBS, remaining 12 teeth of each group were flattened occlusally to remove all enamel and grinded to 500 grit SiC(Pedemet Specimen Preparation Equipment). After applying DBS on the exposed dentin surface, composite resin was applied in the shape of cylinder, which has 5mm diameter, 1.5mm thickness, and light cured. SBS was measured using Instron with a crosshead speed of 0.5mm/min. It was concluded as follows, 1. HLT of AW(mean: $2.59{\mu}m$) was thicker than any other group, and followed by AD, OW, OD in descending order(mean; 2.37, 2.28, $1.92{\mu}m$). Only OD had statistically significant differences(p<0.05) to AW and AD. 2. There were intimate contact of resin and dentin at the interface in wet bonding groups, but gaps or irregular interfaces were observed in dry bonding groups. 3. The length, diameter, density of resin tags were various even in the same group without significant differences between groups and lots of adhesive lateral branches were observed. 4. There were no statistically significant difference of SBS between AB2 and OS, but SBS of wet bonding groups were significantly higher(p<0.05) than dry bonding groups. 5. There were no consistent relationships between HLT and SBS.

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3D프린터를 활용한 융합교육이 초등학생의 컴퓨팅 사고력에 미치는 영향 (The Effect of the Integrative Education Using a 3D Printer on the Computational Thinking Ability of Elementary School Students)

  • 임동훈;김태영
    • 정보교육학회논문지
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    • 제23권5호
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    • pp.469-480
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    • 2019
  • 새로운 2015 개정 교육과정이 추구하고 있는 목적 중의 하나는 4차 산업혁명 시대에 살아갈 학생들이 기본 학습 능력의 바탕 위에 다양한 발상과 도전으로 새로운 것을 창출하는 창의성을 기르는 것이다. 이에 따라 주어진 문제들을 합리적으로 해결하기 위하여 다양한 영역의 지식과 정보를 처리하고 활용할 수 있는 융합적 문제해결 역량이 중요시되고 있다. 이에 본 연구에서는 틴커캐드(Tinkercad) 모델링을 기반으로 하여 3D프린터를 활용한 융합교육을 설계하고 이를 수업에 적용하여 초등학생의 컴퓨팅 사고력 증진에 미치는 영향을 알아보았다. 연구 내용을 검증하기 위해 초등학교 6학년 25명 2개 반을 실험집단과 통제집단으로 나누고 실험집단에는 약 3개월간 3D프린터를 활용한 융합교육 프로그램 12차시를 적용하고, 통제집단에는 같은 시기 동안 동일 주제의 강의식 교과 수업을 진행하였다. 그 후에 컴퓨팅 사고력 검사 도구를 투입하여 사전-사후 검사로 t-검정을 실시하고 그 효과성을 알아보았다. 프로그램 적용 후 사후 검사에서 실험집단은 컴퓨팅 사고력이 통계적으로 유의하게 향상 되었으나, 통제집단은 통계적으로 유의한 차이가 없었다. 이 결과를 통해 틴커캐드 모델링 기반의 3D프린터를 활용한 융합교육이 초등학생의 컴퓨팅 사고력 증진에 긍정적인 영향을 미치는 것으로 보인다.

흡연예방교육이 5학년 초등학생의 흡연에 대한 지식과 태도에 미치는 효과 (The Effects on Knowledge and Attitudes of Smoking by Preventive Education for the Fifth Grade Student in Elementary School)

  • 이미경;문희자
    • 한국보건간호학회지
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    • 제16권2호
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    • pp.388-399
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    • 2002
  • This study would tend to clarify effects on knowledge and attitudes of smoking by preventive education for the fifth grade student in elementary school. It would also hope to contribute to activate smoking preventive education, improvement of health quality for the young and reduce school children's misdeeds. One hundred and sixty-eight school children, the fifth grade student in K city's elementary school have been gathered as testees and divided into two groups : 84 in an experimental group and other 84 in a group for comparison.. Data has been collected between 27th November, 2001 and 8th February, 2002 and methods, which were based on literature study, have been developed by myself and used after reliability test. The process has been formed in this order - pre-survey, experiment (smoking preventive education), the first post-survey and the second post-survey. The pre-survey was to fill the questionnaire and the post survey has done with the same way in 2 and 9 weeks later. The smoking preventive education has been carried out 4 times and the time for each experiment was 40 minutes. The collected data has been analysed by the purpose into $\chi^2-test$, t-test,. F-test, Duncan multiple range test with SPSS. The results of study would be as follows 1. The rate of smoking experience is $17.3\%$ and the biggest motive $(75\%)$ is curiosity. Also $5.4\%$ of respondents reply to have friends smoking a little. 2. The first hypothesis - the group with smoking preventive education would have much knowledge about smoking than comparison group - would be supported with statistical data (t=-3.329, p=.000). 3. The second hypothesis - the group with smoking preventive education would show higher attitude than the other group - would also be backed by statistically meaningful difference (t=-3.856, p=.000). 4. The variables of extent for smoking knowledge would be school record and the variables of extent for smoking attitude is friends' smoking, parents' reaction, experience until now and plan from now on.

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지르코니아 코어의 표면처리 방법에 따른 도재 축성의 전단결합강도 (Shear Bond Strength of Veneering Ceramic and Zirconia Core according to the Surface Treatments)

  • 신천호;황성식;한경순
    • 치위생과학회지
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    • 제13권4호
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    • pp.487-492
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    • 2013
  • 본 연구는 지르코니아 코어 표면처리 방법에 따른 코어와 도재와의 결합기전을 파악하여 도재 수복물의 문제점을 개선하고자 도재와 동일한 구조의 코어를 제작한 후 코어 표면의 거칠기 처리와 liner 적용 방법을 각각 달리한 4개 군의 전단결합강도의 차이를 분석한 바 다음과 같은 결론을 얻었다. 1. 코어의 표면 거칠기 처리 여부는 표면조도에 영향을 주었다(p<0.001). 2. 지르코니아 코어 표면을 표면 거칠기와 liner를 도포한 군(SLT군)이 23.19 MPa로 가장 높았고, 표면 거칠기만 적용한 군(ST군)이 21.17 MPa였으며, liner만 적용한 군(LT군)은 20.53 MPa였고, 표면 비처리 군(NT군)이 16.46 MPa으로 가장 낮은 값을 나타내(p=0.176) 표면처리에 따른 전단 결합강도에 차이가 있을 가능성을 나타냈다. 또한 표면 거칠기와 liner를 도포한 군(SLT군)과 표면 비처리 군(NT군)에서 두 군 간의 차이는 통계적으로 유의하였다(p<0.05). 3. 계면상태는 SLT군이 ST군과 LT군, NT군에 비해 도재결합의 응집된 상태를 나타냈다. 코어의 표면처리 특히 거칠기 처리는 지르코니아 코어와 도재의 물리적 결합 즉, 전단결합강도를 높일 수 있는 의미있는 과정임을 확인하였다.

도시철도역사에서 화재유동에 대한 병렬계산방법연구 (The development of parallel computation method for the fire-driven-flow in the subway station)

  • 장용준;이창현;김학범;박원희
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 춘계학술대회 논문집
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    • pp.1809-1815
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    • 2008
  • 본 연구는 병렬처리기법을 이용하여 지하역사 화재유동을 시뮬레이션 하였다. 화재해석 프로그램으로는 LES(Large Eddy Simulation)화재해석 프로그램 중 하나인 FDS(Fire Dynamics Simulation)를 사용하여 연구를 진행하였으며, 각 Node당 3.0Ghz_2set이 탑재된 6-node parallel Cluster장비를 사용하여 병렬계산을 수행하였다. 시뮬레이션 모델은 광주 금난로 4가 지하역사를 대상으로 하였으며, 총 시뮬레이션 시간은 600s로 하였다. 먼저 Single-CPU와 Multi-CPU를 이용한 병렬계산과의 결과 비교를 위하여 전체역사를 1-Mesh와 8-Mesh로 나누어 각각 Single-CPU계산과 Multi-CPU를 이용하여 계산결과를 비교분석 하였으며, Single-CPU에서 처리가 불가능한 격자수($15{\times}10^6$)를 가지고 승강장 중앙에서의 화재와 객차 내에서의 화재유동분석 하였다. 연구결과 Single-CPU 해석과 Multi-CPU를 이용한 병렬계산에 있어서, 해석결과의 차이는 거의 없는 것으로 나타났다. 또한 계산시간의 비교에서도 14개의 Mesh를 가지고 약 300만개의 격자를 사용한 경우에 있어서 2CPU(4core)와 7CPU(14core)의 계산시간은 1CPU에 비하여 각각, 2배, 5배의 차이를 보였다. 병렬처리기법의 도입으로 Single-CPU의 한계를 극복하여 보다 빠르고 정확한 결과값을 얻을 수 있을 것으로 기대된다. 향후 병렬처리기법연구에 있어서 계산효율성 증대를 위한 연구가 계속적으로 진행되어야 할 것이다.

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Modified Continuous Wave Technique을 이용한 근관충전시 형성된 치근단 크기가 치근단 폐쇄에 미치는 영향 (EVALUATION OF THE INFLUENCE OF APICAL SIZES ON THE APICAL SEALING ABILITY OF THE MODIFIED CONTINUOUS WAVE TECHNIQUE)

  • 류무현;정일영;이승종;신수정;김의성
    • Restorative Dentistry and Endodontics
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    • 제33권1호
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    • pp.66-75
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    • 2008
  • 본 연구에서는 근관형성의 치근단 크기가 근관 충전의 치근단 폐쇄에 미치는 영향에 대해 알아보고자 하였다. 36개의 단근관, 단근치를 대상으로 3가지 치근단 크기 (Master apical file : #25, #40, #60)에 따라 3가지 실험군으로 나누어 $Profile^{(R)}$$LightSpeed^{(R)}$를 이용하여 근관을 확대하고, Modified continuous wave technique으로 근관충전을 시행하였다. 미세누출의 측정을 위해 실험군당 10개의 치아를 1주일간 India ink에 넣어 색소 침투를 일으키고 치아를 투명화시켜 미세누출의 정도를 측정하였다. 미세누출에 치근단 크기가 미치는 영향을 분석하기 위하여 Kruskal-Wallis one-way ANOVA를 시행하였고, 사후 검정을 위하여 Student-Newman-Keuls method를 시행하였다. 또한, 치아 단면의 형태를 관찰하기 위하여 색소 침투까지 실행된 각 실험군당 2개의 치아를 근첨 1 mm에서 4 mm까지 1 mm간격으로 수평 절단하고 사진 촬영하였다. 각 실험군에서 측정된 미세누출양을 Krustal-Wallis one-way ANOVA에서 분석한 결과 치근단 크기는 유의성 있게 (P < 0.05) 미세누출에 영향을 미쳤으며 치근단 크기가 클수록 미세누출의 평균간과 표준편차 값은 감소하는 경향을 보였다. Student-Newman-Keuls method를 통한 사후 검정에서 치근단 크기가 #25 - #40, #25 - #60에서 유의 한 차이를 보였으며 #40 - #60간에는 통계적인 유의차는 없었다. 단면형태에서는 대부분의 치아에서 난원형의 근관 형태를 관찰 할 수 있었고, 치근단의 크기가 작을수록 성형된 근관에 불규칙한 내면이 존재하였고 gutta-percha나 sealer로 충전되지 않는 recess의 면적이 증가함을 알 수 있었으며 이러한 recess는 미세누출의 통로가 됨을 확인 할 수 있었다. 본 연구 결과, Modified continuous wave technique으로 근관충전시 근관 형성된 치근단 크기가 커질수록 보다 일관되고 성공적 인 결과를 예상할 수 있는 근관충전을 시행할 수 있음을 알 수 있었다.

중학생의 인터넷음란물 접속과 성 의식의 관계 (Relationship between Access to Lewd Internet Contents by Middle School Students and Their Awareness of Sex)

  • 임종인;최인숙
    • 한국학교ㆍ지역보건교육학회지
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    • 제4권
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    • pp.117-139
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    • 2003
  • The purpose of this research lies in presenting logical viability for the measures that curtail access to lewd Internet contents by middle school students amidst the reality in which lewd contents are circulated freely through the Internet, a medium that the middle school students find most easy to access. In order to establish right form of awareness towards sex, this research identified the ways they access the lewd Internet contents, their reaction after the exposure to those contents, their knowledge of sex, their concerns regarding sex and their accessibility to sexual activities in order to conduct a comparative analysis on the relationship between lewd Internet contents and their awareness of sex. First, realities of accessing lewd Internet contents and reactions according to the demographics of middle school students There isa significant difference in the experience of accessing lewd Internet contents in terms of gender. Mostly, male students tend to access the contents more. As for the way they access the lewd Internet contents, both male and female students replied that they access through spam mail of lewd nature. Thus, measures to address this problem are needed urgently. As to when they first accessed the lewd contents, most of the research subjects replied that they accessed either in elementary school period or in the early middle school period. This shows that most of the students got exposed to lewd contents even before they could establish positive, correct awareness of sex. Thus, there is a risk that they may formulate wrong kind of sexual awareness. Accordingly, it is necessary to develop measures through focused sex education. Students are divided into two groups according to the time they spend on the contents averagely: those who spend over one hour and those who spend less than an hour on the lewd contents. If the students spending longer hours are not to be checked and properly guided, it may lead to increasing cases of sexual delinquencies due to their wrongly formed awareness of sex. When the question of existence(non-existence) of guardian was addressed, students with both parents tend to access the lewd Internet contents in a more diverse manner and tend to access more compared to those students from single parent or no-parent families. Accordingly, guardians need to pay attention to how their children are using the Internet. Second, awareness of sex depending on the middle school students' demographics In case of sexual knowledge, middle school students shows relatively high level of knowledge. In particular, female students are found more knowledgeable than male students, and the students in upper years are more knowledgeable as well. As a result, this research recommends that the students in lower years should be guided with more basc and detailed information, while those in upper years need to be taught to form and express their own thoughts and attitudes and to build up independence on this matter. In case of worries about sex, both male and female students don't worry too much about it. However, male students are more concerned about sex than female students in a more diverse ways. As for the differences by academic year, concerns for sex increase, as students get older. Accordingly, sex education that helps establish sound perception of the opposite sex and that focuses on the etiquettes that one must adhere to at the presence of the opposite sex need to be conducted against middle school students. In case of accessibility to sex, male students manifest higher tendency than female students. As for the differences by academic year, those in the first and second years show higher accessibility than those in their third year. In general, younger students tend to be more open-minded toward sex. Accordingly, students in lower academic years need to undergo basic knowledge oriented sex education, whereas those in upper academic years need to undergo discussion centered sex education where they subject to questions regarding their attitude and opinion. Third, relationship between the reactions after the exposure to the lewd Internet contents and their awareness of sex As the frequency of contact with lewd Internet contents increases, awareness of sex increases as well. Thus, the lewd Internet contents contribute to the increase in students' concern for sex as well as increase in accessibility to sex, which eventually become barriers to students' establishment of a healthy perception of sex. Reactions to sex after the exposure to lewd Internet contents and awareness of sex indicate a significant correlation. However, negative correlation is manifested with knowledge of sex. Thus, it is possible to know that the greater access to lewd Internet contents does not necessarily translate into increase in knowledge of sex. However, the study showed there is a correlation between concerns for sex and the level of accessibility to sex. In more detail, the more reactions to the contents they show, the more concerns for sex they have and the more positively they take acceptability to sex. Moreover, it is necessary to develop necessary measures since textbooks today do not include measures needed to address the lewd Internet contents. Given the above findings, it is necessary to continue to complement structural measures in order to prevent easy access of lewd Internet contents by middle school students. Moreover, it is necessary to be considerate of the students so that they themselves can form a healthy Internet culture and grow up within positive framework for the sex education.

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지르코니아의 다양한 표면처리 방법과 레진시멘트 종류에 따른 전단결합강도 비교 (Comparison of shear bond strength according to various surface treatment methods of zirconia and resin cement types)

  • 배지현;배강호;박태석;허중보;최재원
    • 대한치과보철학회지
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    • 제59권2호
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    • pp.153-163
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    • 2021
  • 목적: 본 연구는 지르코니아의 거칠기 증가를 위한 4가지 표면처리 방법과 3종의 레진시멘트가 전단결합강도에 미치는 영향을 알아보고자 하였다. 재료 및 방법: 총 120개의 지르코니아 시편을 표면처리 방법에 따라 4개의 군으로 나누었다: 대조군, 아무 처리를 하지 않은 군; APA50군, 50 ㎛ 크기의 Al2O3로 Airborne-particle abrasion (APA) 처리를 시행한 군; APA125군, 125 ㎛ 크기의 Al2O3로 APA 처리를 시행한 군; ZA군, ZrO2 slurry를 적용한 군. 각 군에 3종의 레진시멘트(Panavia F 2.0, Superbond C&B, Variolink N)를 접착하고, 만능시험기를 이용하여 전단결합강도를 측정하였다. 주사전자현미경을 이용해 각 군의 대표 표본의 표면을 관찰하였다. 표면처리 방법과 레진시멘트 종류에 따른 상호작용이 존재하는지 알아보기 위하여 Two-way ANOVA를 실시하였고, 각 군 간의 통계적 차이를 알아보기 위해 One-way ANOVA를 시행하였다. 사후검정으로 Tukey HSD test를 실시하였다(α = .05). 결과: 표면처리에 따른 전단결합강도 비교에서, APA125군, APA50군, ZA군, 대조군 순으로 높은 값을 보였고, APA처리를 시행한 군(APA50군, APA125군) 간에는 통계적으로 유의한 차이가 없었다(P > .05). 또한, ZA군은 대조군보다 유의성 있게 높은 값을 보였다(P < .05). 레진시멘트 종류에 따라서는 Panavia F 2.0, Superbond C&B, Variolink N 순으로 높은 전단결합강도를 보였다(P < .05). APA50군과 APA125군에서는 거칠고 불규칙한 표면이 관찰되었고, ZA군에서는 작고 불규칙한 다공성과 거친 표면이 관찰되었다. 결론: 본 연구의 한계내에서, APA 처리와 ZrO2 slurry를 적용했을 때 지르코니아의 표면 거칠기가 증가됨을 확인할 수 있었고, MDP를 함유한 Panavia F 2.0가 지르코니아와의 가장 높은 전단결합강도를 보였다.

저칼슘식이와 방사선조사가 백서 악골에 미치는 영향의 실험적 연구 (THE EFFECT OF LOW DIETARY CALCIUM AND IRRADIATION ON MANDIBLE IN RATS)

  • 이선기;이상래
    • 치과방사선
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    • 제23권2호
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    • pp.229-250
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    • 1993
  • This study was performed to investigate the morphological and structural changes of bone tissues and the effects of irradiation on the mandibular bodies of rats which were fed low calcium diets. In order to carry out this experiment, 160 seven-week old Sprague-Dawley strain rats weighing about 150 gm were selected and equally divided into one normal diet group of 80 rats and one low calcium diet group with the remainder. These groups were then subdivided into two groups, 40 were assigned rats for each subdivided group, exposed to radiation. The Group 1 was composed of forty non-irradiated rats with normal diet, Group 2 of forty irradiated rats with normal diet, Group 3 forty non-irradiated rats with low calcium diet, and Group 4 forty irradiated rats with low calcium diet. The two irradiation groups received a single dose of 20 Gy on the jaw area only and irradiated with a cobalt-50 teletherapy unit. The rats with normal and low calcium diet groups were serially terminated by ten on the 3rd, the 7th, the 14th, and the 21st day after irradiation. After termination, both sides of the dead rats mandible were removed and fixed with 10% neutral formalin. The bone density of mandibular body was measured by use of bone mineral densitometer(Model DPX -alpha, Lunar Corp., U.SA). Triga Mark ill nuclear reactor in Korea Atomic Research Institute was used for neutron activation and then calcium contents of mandibular body were measured by using a 4096 multichannel analyzer (EG and G ORTEC 919 MCA, U.SA). Also the mandibular body was radiographed with a soft X-ray apparatus(Hitex Co., Ltd., Japan). Thereafter, the obtained microradiograms were observed by a light microscope and were used for the morphometric analysis using a image analyzer(Leco 2001 System, Leco Co., Canada). The morphometric analysis was performed for parameters such as the total area, the bone area, the inner and outer perimeters of the bone. The obtained results were as follows: 1. In the morphometric analysis, total area and outer perimeter of the mandibular bodies of Group 3 were a little smaller than that of Group 1. The mean bone width and bone area were much smaller than that of Group 1 and the inner perimeter of Group 3 was much longer than that of Group 1. The total area and outer perimeter of Group 2 and Group 4 showed little difference. The mean bone width and bone area of Group 4 were smaller than that of Group 2 and the inner perimeter of Group 4 was longer than that of Group 2. 2. The remarkable decreases of the number and thickness of trabeculae and also the resorption of endosteal surface of cortical bone could be seen in the microradiogram of Group 3, Group 4 since the 3rd day of experiment. On the 21st day of experiment, the above findings could be more clearly seen in Group 4 than in Group 3. 3. The bone mineral density of Group 3 was lesser than that of Group 1 and the bone mineral density of Group 4 was lesser than that of Group 2 on the 7th, 14th, 21st days. The irradiation caused the bone mineral density to be decreased regardless of diet. In the case of Groups with low calcium diet, the bone mineral density was much decreased on the 21st day than on the 3rd day of experiment. 4. The calcium content in mandible of Group 3 was smaller than that of Group 1 throughout the experiment. roup 4 showed the least amount of calcium content. The irradiation caused the calcium content to be decreased regardless of diet. In the case of Groups with low calcium diet, the calcium content was much decreased on the 21st day than on the 3rd day of experiment. In conclusion, the present study demonstrated that morphological changs and decrease of bone mass due to resorption of bone by low calcium diet, and that the resorption of bone could be found in the spongeous bone and endosteal surface of cortical bone. So the problem of resorption of bone must be considered when the old and the postmenopausal women are taken radiotherapy because the irradiation seems to be accelerated the resorption of osteoporotic bone.

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치과용 복합레진으로 수리된 CAD-CAM hybrid 수복물의 전단결합강도 (Shear bond strength of dental CAD-CAM hybrid restorative materials repaired with composite resin)

  • 문윤희;이종혁;이명구
    • 대한치과보철학회지
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    • 제54권3호
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    • pp.193-202
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    • 2016
  • 목적: 본 연구에서는 치과용 CAD-CAM (computer aided design-computer aided manufacturing) hybrid 수복재료인 LAVA Ultimate와 VITA ENAMIC을 광중합 복합레진을 사용하여 수리할 때 표면처리방법(grinding, air abrasion with aluminum oxide, HF acid)과 접착재료(Adper Single Bond 2, Single Bond Universal)의 종류가 두 재료 사이의 전단결합강도에 어떠한 영향을 미치는지 알아보고자 하였다. 재료 및 방법: LAVA Ultimate와 VITA ENAMIC 시편을 30일간 $37^{\circ}C$의 인공타액(Xerova solution)에 보관하여 시효처리를 실시한 후 각각 SiC paper grinding한 것, grinding 후 air abrasion처리를 추가한 것, grinding 후 HF 처리한 것으로 분류하고 각각 no bonding, Adper Single Bond 2, 또는, Single Bond Universal 도포로 세분하여 9개의 group, 총 18개의 subgroup으로 나누어 실험을 실시하였다(N=10). HF 처리group에서는 도재시편을 대조군으로 추가하였다(N=10). 표면 처리 후 광중합 복합레진(Filtek Z250)을 각각의 시편에 부착하고 이를 1주일간 실온의 물에 침적시켰고 이후 전단결합강도를 측정하고 파절양상 및 표면처리 효과를 SEM으로 확인하였다. One-way ANOVA를 이용하여 group 간의 유의성을 분석하였고 사후 분석으로 Scheffe test를 실시하였다(${\alpha}=.05$). 결과: 실험 결과 접착재료 처리를 한 group들이 접착재료 처리를 하지 않은 group에 비해 모든 표면처리에서 더 높은 전단결합력을 나타내었으며, 표면처리만 시행한 group에서는 aluminum oxide air abrasion이 전단결합력의 증가에 약간의 영향을 미치는 것으로 나타났으나 통계적 유의성은 보이지 않았다. 결론: LAVA Ultimate와 VITA ENAMIC의 두 재료를 광중합 복합레진을 이용하여 수리를 실시할 경우 각각의 재료에 적합한 표면처리방법과 접착재료의 선택에 대한 연구가 더 필요할 것으로 사료된다. 특히 LAVA Ultimate의 경우 접착재료의 사용은 추천된다고 사료되었다.