• 치위생과학회지
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• 제19권4호
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• pp.213-219
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• 2019

Background: Smoking exerts an adverse effect on the periodontal tissue by reorganizing the ecosystem of oral microorganisms and is considered to be an important factor in the development of periodontal disease. Although cross-sectional studies on smokers and non-smokers have been attempted to investigate the microbial differences in periodontal oral cavity, only few studies have been conducted to investigate the changes in oral microorganisms during smoking cessation. The purpose of this study was to investigate the changes of bacteria in saliva and gingival crevicular fluid (GCF) over a period of one year among 11 smokers trying to quit smoking. Methods: Eleven smokers trying to quit smoking visited the clinic at baseline, two weeks, two months, four months, six months, and 12 months to give saliva and GCF samples. The amounts of 16S rRNA, Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum subsp. nucleatum, Streptococcus mutans, and Streptococcus sobrinus in saliva and GCF were quantified using real-time polymerase chain reaction TaqMan probe assay. The results were analyzed by nonparametric statistical analysis using Friedman test and Spearman correlation coefficient. Results: After cessation of smoking, the amounts of 16S rRNA corresponding to P. gingivalis, F. nucleatum, P. intermedia, and T. denticola in saliva decreased and then again increased significantly. The amount of F. nucleatum 16S rRNA in GCF decreased significantly after smoking cessation. Positive correlations were observed between 16S rRNA and F. nucleatum and between F. nucleatum and T. denticola in saliva and GCF. Conclusion: Even if the number of subjects in this study was small, we suggest that smoking cessation may reduce the total bacterial amount and F. nucleatum in GCF. However, the results regarding changes in the microbial ecosystem due to smoking or smoking cessation were inconsistent. Therefore, further in-depth studies need to be carried out.

• The Journal of Advanced Prosthodontics
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• 제9권3호
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• pp.159-169
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• 2017

PURPOSE. The purposes of this study were to evaluate the marginal and internal gaps, and the potential clinical applications of three different methods of dental prostheses fabrication, and to compare the prostheses prepared using the silicone replica technique (SRT) and those prepared using the three-dimensional superimposition analysis (3DSA). MATERIALS AND METHODS. Five Pekkton, lithium disilicate, and zirconia crowns were each manufactured and tested using both the SRT and the two-dimensional section of the 3DSA. The data were analyzed with the nonparametric version of a two-way analysis of variance using rank-transformed values and the Tukey's post-hoc test (${\alpha}=.05$). RESULTS. Significant differences were observed between the fabrication methods in the marginal gap (P < .010), deep chamfer (P < .001), axial wall (P < .001), and occlusal area (P < .001). A significant difference in the occlusal area was found between the two measurement methods (P < .030), whereas no significant differences were found in the marginal gap (P > .350), deep chamfer (P > .719), and axial wall (P > .150). As the 3DSA method is three-dimensional, it allows for the measurement of arbitrary points. CONCLUSION. All of the three fabrication methods are valid for measuring clinical objectives because they produced prostheses within the clinically acceptable range. Furthermore, a three-dimensional superimposition analysis verification method such as the silicone replica technique is also applicable in clinical settings.

• Journal of Preventive Medicine and Public Health
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• 제44권3호
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• pp.101-110
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• 2011

Objectives: Screening for colorectal cancer is considered cost effective, but is underutilized in the U.S. Information on the efficiency of "tailored interventions" to promote colorectal cancer screening in primary care settings is limited. The paper reports the results of a cost effectiveness analysis that compared a survey-only control group to a Centers for Disease Control (CDC) web-based intervention (screen for life) and to a tailored interactive computer-based intervention. Methods: A randomized controlled trial of people 50 and over, was conducted to test the interventions. The sample was 1224 partcipants 50-70 years of age, recruited from Kelsey-Seybold Clinic, a large multi-specialty clinic in Houston, Texas. Screening status was obtained by medical chart review after a 12-month follow-up period. An "intention to treat" analysis and micro costing from the patient and provider perspectives were used to estimate the costs and effects. Analysis of statistical uncertainty was conducted using nonparametric bootstrapping. Results: The estimated cost of implementing the web-based intervention was $40 per person and the cost of the tailored intervention was $45 per person. The additional cost per person screened for the web-based intervention compared to no intervention was $2602 and the tailored intervention was no more effective than the web-based strategy. Conclusions: The tailored intervention was less cost-effective than the web-based intervention for colorectal cancer screening promotion. The web-based intervention was less cost-effective than previous studies of in-reach colorectal cancer screening promotion. Researchers need to continue developing and evaluating the effectiveness and costeffectiveness of interventions to increase colorectal cancer screening.

• 영재교육연구
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• 제21권3호
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• pp.703-718
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• 2011

팀기반학습은 짜임새 있는 팀활동을 통해 구성원들의 의사결정능력, 조정능력, 협동심, 문제해결력을 향상시켜주기 때문에 영재교육에 있어 중요한 역할을 할 수 있다. 그래서 팀기반학습에 기초한 프로그램을 개발하고, 이를 영재학생들에게 적용시켰을 때 창의적 문제 해결력의 향상 효과에 대해 연구하였다. 경남 산청군의 S 초등학교 4, 5학년 영재학급 학생 13명(남 3명, 여 10명)을 대상으로 실시하였고, 총 10차시 분량의 프로그램을 개발하였다. 창의적 문제해결력의 향상 정도를 파악하기 위해 자기보고식 형태의 검사도구를 사용하였다. 적은 학생 수로 인하여 사전사후 결과를 비모수통계처리한 결과 유의수준 5% 이내에서 유의미한 향상효과가 있었다. 특히 확산적 사고, 비판적 논리적 사고에서 크게 향상되었다. 이처럼 팀기반학습에 기초한 프로그램은 영재학생들의 창의적 문제해결력 향상에 효과적이므로, 창의적 문제해결력 향상을 필요로 하는 영재학급에서 널리 사용될 수 있다.

• 응용통계연구
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• 제24권2호
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• pp.269-278
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• 2011

스코어 변수의 민감도와 특이도와의 관계로 표현한 ROC 곡선을 더욱 정확한 진단을 위하여 분포함수와 공변량을 고려한 연구가 많이 진행되었다. 공변량을 고려하는 회귀분석 방법을 사용하였으며 이때 분포함수를 정규분포로 가정하거나 잔차의 분포함수를 추정하여 ROC 분석을 하였다. 본 연구는 분포함수가 주어지지 않으며 진단에 영향을 주는 공변량을 모르는 일반적인 상황에서 논의하였다. 확률변수인 스코어와 두 개의 보모집단으로 구성된 신용평가 자료에 적합한 분포함수를 추정하기 위하여 여러 개의 정규분포가 혼합된 정규혼합분포를 사용하여 ROC 분석을 한다. 고전적인 비모수적이고 경험적인 ROC 곡선에 적합한지를 파악하기 위하여 AUC 통계량을 사용하여 비교하며, 본 연구에서 제안한 정규혼합분포를 이용한 ROC 곡선이 다른 방법으로 구한 ROC 곡선보다 적합함을 보였다.

• 응용통계연구
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• 제19권1호
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• pp.149-161
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• 2006

CART로 대표되는 의사결정나무의 알고리즘에서 가장 중요한 요소는 분리변수의 선택방법이다. 대부분의 알고리즘은 변수의 형태가 연속형인지, 혹은 명목형(nominal)인지에 따라 별개의 변수선택방법을 적용한다. 하지만 변수의 형태가 순서형(ordinal)인 경우에는 그 변수를 연속형으로 취급하여 연속형 변수선택방법을 적용하는 것이 대부분이다. 이것은 CART와 같은 Greedy탐색을 이용하는 방법에는 문제점이 발생하지 않는다. 하지만 Greedy탐색의 약점을 보완하기 위해 통계이론을 이용하여 개발된 최근의 방법들에는 최선의 대처방법이 아니다. 따라서 본 연구에서는 의사결정 나무에서 분리변수를 선택하는데 있어서 비모수적 접근 방법인 Clamor-von Mises 검정을 이용한 방법을 순서형 변수에 사용하는 것을 제안하고, CART, C4.5, QUEST, CRUISE등 기존 알고리즘과 본 연구에서 제안하는 방법의 순서형 변수 선택력을 비교하였다. 모의실험의 결과, Clamor-von Mises 검정을 이용한 변수선택방법은 순서형 변수의 분류력을 기존 방법들에 비해 더 정확히 예측하는 좋은 성과를 보여주었다.

• Journal of Periodontal and Implant Science
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• 제43권6호
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• pp.269-275
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• 2013

Purpose: In this study, the effect of calcium sodium phosphosilicate (NovaMin) desensitizing agent, which is a powder-based system, and hydroxyethyl methacrylate and glutaraldehyde (Gluma desensitizer), which is liquid-based system, on dentinal tubule occlusion was analyzed by scanning electron microscope. The effects of the above two along with one control group were compared to determine the more effective method of sealing the dentinal tubules after initial application. Methods: Twenty specimens were allocated to each of 3 groups: Control, Gluma desensitizer, and NovaMin. Two additional samples were also prepared and treated with Gluma and NovaMin; these samples were longitudinally fractured. The specimens were prepared from extracted sound human premolars and were stored in 10% formalin at room temperature. The teeth were cleaned of gross debris and then sectioned to provide one to two dentin specimens. The dentin specimens were etched with 6% citric acid for 2 minutes and rinsed in distilled water. Control discs were dried, and the test discs were treated with the desensitizing agents as per the manufacturer's instructions. The discs as well as longitudinal sections were later analyzed under the scanning electron microscope. The proportions of completely occluded, partially occluded, and open tubules within each group were calculated. The ratios of completely and partially occluded tubules to the total tubules for all the groups was determined, and the data was statistically analyzed using nonparametric tests and statistical significance was calculated. Results: NovaMin showed more completely occluded tubules ($0.545{\pm}0.051$) while Gluma desensitizer showed more partially occluded tubules ($0.532{\pm}0.075$). The differences among all the groups were statistically significant ($P{\leq}0.05$). Conclusion: Both materials were effective in occluding dentinal tubules but NovaMin appeared more promising in occluding tubules completely after initial application.

• The Journal of Advanced Prosthodontics
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• 제10권5호
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• pp.347-353
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• 2018

PURPOSE. The purpose of this study was to evaluate the marginal discrepancy of heat-pressed ceramic veneers manufactured using a CAD/CAM system. MATERIALS AND METHODS. The ceramic veneers for the abutment of a maxillary left central incisor were designed using a CAD/CAM software program. Ten veneers using a microstereolithography apparatus (AM group), ten veneers using a five-axis milling machine (SM group), and ten veneers using a traditional free-hand wax technique (TW group) were prepared according to the respective manufacturing method. The ceramic veneers were also fabricated using a heat-press technique, and a silicone replica was used to measure their marginal discrepancy. The marginal discrepancies were measured using a digital microscope (${\times}160$ magnification). The data were analyzed using a nonparametric Kruskal-Wallis H test. Finally, post-hoc comparisons were conducted using Bonferroni-corrected Mann-Whitney U tests (${\alpha}=.05$). RESULTS. The $mean{\pm}SD$ of the total marginal discrepancy was $99.68{\pm}28.01{\mu}m$ for the AM group, $76.60{\pm}28.76{\mu}m$ for the SM group, and $83.08{\pm}39.74{\mu}m$ for the TW group. There were significant differences in the total marginal discrepancies of the ceramic veneers (P<.05). CONCLUSION. The SM group showed a better fit than the AM and TW groups. However, all values were within the clinical tolerance. Therefore, CAD/CAM manufacturing methods can replace the traditional free-hand wax technique.

• 대한한의진단학회지
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• 제20권2호
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• pp.67-75
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• 2016

Objectives There was a correlation between respiratory index and Profile of Mood States (POMS). However, no study has examined the relationship between hyperventilation and POMS. Therefore, this study showed differences in POMS subscales and respiratory patterns between hyperventilation group and normal group. Methods 20 healthy men and women were to complete Nijmegen and Korean-Profile of Mood States(K-POMS) questionnaire aimed at subjects (13 men, 12 women). By attaching a capnometer to the nasal cavity portion, end-tidal $PCO_2$ was measured. Also, marker was attached at Zhangmen, Juque, Shuifen. The movement of the marker was taken as a web cam. Statistical analysis Mann Whitney U test was used for the nonparametric methods. Results In the subscale of K-POMS were significant differences(Tension-0.001, Anger-0.007, Fatigue-0.002, Depression -0.004) between the normal group and the group with the hyperventilation. In addition, between the two groups were obtained a significant result(0.046) in the movement of the Shuifen acupoint. Conclusions Nijmegen questionnaire score is higher, the higher negative subscale scores of K-POMS. Also, differences in Nijmegen questionnaire score may help to determine the presence or absence of the abdominal breathing.

• 영재교육연구
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• 제21권1호
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• pp.19-38
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• 2011

이 연구에서는 현재 학생들의 인지양식에 부합되는 UCC 활용 교수 학습 모형(4C 모형)을 영재학생들에게 적용하였을 때 과학 관련 정의적 특성의 효과 면에서 어떤 성별 특성이 있는지 알아보고자 하였다. 이를 위해 영재학급 학생들을 대상으로 UCC 활용 프로젝트학습을 실시한 후 그에 대한 인식을 조사하였고, 과학 관련 정의적 특성에서의 사전 사후 검사 결과를 비모수 검정을 통해 분석해 보았다. 그 결과, 영재학급 학생들은 UCC 활용 프로젝트 학습에 매우 적극적으로 임하였으며 남학생보다 여학생의 흥미와 참여도가 더 높았고, UCC 제작에 관한 어려움은 남학생이 더 많이 느끼는 것으로 나타났다. 또한 남학생들의 경우 유의미한 변화가 없었지만 여학생들의 창의성이 향상되었고, 과학 불안이 감소되었다. 따라서 UCC 활용 프로젝트학습은 남학생보다 여학생에게 더 효과적임을 알 수 있었다.