• Journal of the Institute of Electronics Engineers of Korea SP
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• 제42권5호
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• pp.29-40
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• 2005

According as base of digital hologram has been magnified, discussion of compression technology is expected as a international standard which defines the compression technique of 3D image and video has been progressed in form of 3DAV which is a part of MPEG. As we can identify in case of 3DAV, the coding technique has high possibility to be formed into the hybrid type which is a merged, refined, or mixid with the various previous technique. Therefore, we wish to present the relationship between various image/video coding techniques and digital hologram In this paper, we propose an efficient coding method of digital hologram using standard compression tools for video and image. At first, we convert fringe patterns into video data using a principle of CGH(Computer Generated Hologram), and then encode it. In this research, we propose a compression algorithm is made up of various method such as pre-processing for transform, local segmentation with global information of object image, frequency transform for coding, scanning to make fringe to video stream, classification of coefficients, and hybrid video coding. Finally the proposed hybrid compression algorithm is all of these methods. The tool for still image coding is JPEG2000, and the toots for video coding include various international compression algorithm such as MPEG-2, MPEG-4, and H.264 and various lossless compression algorithm. The proposed algorithm illustrated that it have better properties for reconstruction than the previous researches on far greater compression rate above from four times to eight times as much. Therefore we expect that the proposed technique for digital hologram coding is to be a good preceding research.

• Research in Community and Public Health Nursing
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• 제15권4호
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• pp.587-599
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• 2004

Purpose: The purpose of this study is to compare abdomen-fat rate, life style and social-support between normal weight women and obese women. Method: 304 women objectives from their 30 to 59 years of age were selected living in Je-chon city, Chung-Buck province and their height and weight were measured from April 1st to June 30th, 2003. Data were classified into low-weight group ($18.5kg/m^2$), normal-weight group ($18.5{\sim}22.9kg/m^2$), over weight group ($23{\sim}24.9kg/m^2$), and obese group ($25kg/m^2$) following the Korean Conference of Obesity, 2001. in which 119 people in the normal weight group and 91 people in the obese group, i.e. total 210 people were analyzed in sequence. Using SPSS Win 10.1 Program, frequency and percentile, and by ANOVA, $X^2-test$ and t-test were treated. Results: The average age of obese women was 46.68 distributing 40.7% of forties and 39.6% of fifties while normal-weight women were average 41.73-year old distributing 53.8% of forties and 34.5% of thirties, which revealed aged in obese women. The body fat rate of obese women averaged $37.52{\pm}4.17%$, in which 98.9% of obese women and 21.0% of normal weight women with a more than 30% of body-fat rate resulted in a higher body-fat rate in obese women. The waists of obese women averaged $88.37{\pm}8.22cm$, in which more than 85cm showed in obese women of 68.2% and normal weight women of 7.6% indicating a higher waist-fat rate in obese women. The abdomen-fat rate of more than 0.85 of waist vs hip-fat showed 74.7% in obese women and 58.4% in normal weight women, indicating a higher abdomen-fat rate in obese women. Obese women and normal weight women showed significant differences in education level, number of children, religion, menstrual status, and mother's weight. Especially, obese women ate hotter or saltier food than normal weight women preferring meat. However, no significant differences appeared in marital status, social economic status. occupation. eating habits. smoking. drinking and physical exercise. Social support levels showed a lower rate in obese women than in normal weight women, indicating a statistically significant difference (p<.05). Observing areas of social support, obese women showed lower rates in attachment/intimacy, social integrity, opportunity of foster and confidence in value except help and instruction, which indicated a statistically significant difference (p<.05). Social support for obese women showed significant differences in age, education level, social hierarchy, religion and menstrual status. Obese women were more negative than normal weight women in health recognition, indicating a statistically significant difference (p<.01). Normal weight women showed higher health recognition when provided high social support and significantly low (p<.01) health recognition when provided low social support. However, there was no significant difference in health recognition in obese women whether high or low social support was given. The health recognition of obese women showed significant differences in age, education level, social hierarchy, number of children, menstrual status, physical exercise, eating habits, eating taste and preference of food. Conclusion: Obese women showed elder than normal-weight women, higher body-fat rate and abdomen-fat rate, lower social support, and a tendency to more negative health recognition. Therefore, providing weight-control programs for the treatment of obesity and prevention of recurrence for obese women to prevent progressing to adult disease and promote a healthy life, we suggest that better eating habits and the encouragement of regular physical exercise should be included, as well as total approachment on change of health recognition and social support would be needed.

• Journal of Korean Public Health Nursing
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• 제4권1호
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• pp.37-55
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• 1990

Every country in the world has been trying to expand the basic health right for the peoples as W.H.O has established the goal 'health for AU' by the year of 2000. Related to this goal, our government authority has establish the policy 'the insurance of health for all' into effect from July 198\). Recently hospitalshave been making a ceaseless effort for the plan for the rationalization of its management the academic World is making it a subject of discussion by doing the secure of manpower at a resonable level and the increase of productivity by the manpower. As a result of the efforts the study was established to secure the numbers of nursing manpower at a resonable level and use the unskilled persons at the utilizing field and seek the possible area of their activity for more efficient service through the investigation of ablity of simple nursing activities of regiestered nurses and nurse aides for rational function according to the educational levels and talents. The method of study was established by the registered nurses and nurse and nurse aides(R.N 229, N.A 226) who are working in 15 hospitals with over 200 beds. This surrey was conducted from Mar 29, 1989 to April 8, 1989. The method to test the degree of importance, difficulties, and the abillity of performance of a simple nursing activities was classified into 35 activities on the basis of references on this field. The degree of importance was composed from point l(Not so important) to 5(Very important). the degree of difficulties. was composed as follows; very easy - Point 1 very difficult and complicated - Point 5. and the ability of performance was composed from point 1 to 5. The materials gathered through the survey were analyzed with frequency, mean standard deviation, percentage. t-test, Anova, pearson's coefficient of correlation, stepwise multiple regression. factor analysis, discriminant analysis. The obtained results are summarized as follows: 1. The recognition values of the simple nursing activities of each group of registered nurse and nurse aides show; The degree of importance; 4.04 and 4.26 The degree of difficulties; 2.72 and 2.94 The ability of performance; 2.07 and 2.38 The brief summary shows there are little differences between who two groups the simple nursing activities turned out to be easy and simple work. 2. Regardless of the degree of importance, and difficulties, the ability of performance the important in fluencing of the degree of the simple nursing activities between the registered nurses and nurse aides was the order of educational level, hospital career, working career in wards and ages of the registered nurses and ages and hospital creer of nurse aides. The result was that the simple nursing activities could easily be familiar through the training of their working environment and period of experience. 3. Among the 35 simple nursing activities the items capable of resonable entrusting to the nurse aides are 5 that is helping bed-bathing, 8itz Bath, using bed pan, care while delivering patient, accompaying patient when visitor's check. There wasn't and differences between RN and nurse aides in performing the above 5 items. In anywhere. so we can say obviosuly that this nursing activities should be performed under the nursing system of which chief of nurse are supposed to supervise nurse aides as a possible function to be entrusted. In view of the above mentioned results, therefore, this partial functional job of the simple nursing activities can able be entrusted to the nurse aides through the regular training course. In case of these functional activities could be entrusted under, the responsibility of registered nurse, we can able suggest to for that there are the following advantages: 1.. In the nursing activities-affairs, the qualified guarantee of the nursing services can be kept and increased or promotoed with accommodation of the required nursing service and roles being expanded presently. 2. In the productivity of the hospital manpower, therefore, we have comt to view and consider in favourly that when an automational administration times would be come in the near future time to hospital affairs as a reality, to utilize the existing nures aides is better rather than investing so as to develop the other source manpowers or seek its for the efficient business management in the operational strategy or its policy.

• Journal of the Korean earth science society
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• 제22권4호
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• pp.327-338
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• 2001

In this study, the short-term variability of methane concentrations were investigated over 24-hr scale. The data obtained form the Moo-Ahn (MAN) station located in the western coastal area of Korea were analyzed from various respects to describe its distribution characteristics over short term scale. The MAN data were compared with those obtained from the two major background observatory sites: Point Barrow (Alaska) and Mauna Loa (Hawaii). The mean concentration of methane for the whole study period, when computed using the daily mean values, was found to be 1898${\pm}$85.3ppb (N=812). The mean values for the two comparable sites were observed to be 1832${\pm}$29.6ppb (N=823) for Point Barrow and 1745${\pm}$14.8ppb (N=818) for Mauna Loa. According to the analysis of frequency distribution. the mode value for the MAN area is found to be 1900ppb, but the mean concentration for Point Barrow and Mauna Loa are shown to have relatively low values of 1850 and 1750ppb, respectively. When examined over diurnal scale, the CH$_4$data for the MAN area exhibit a rather consistent trend; CH$_4$level is low during the daytime (after 6:00 A.M) and rises during the nighttime. The findings of the generally enhanced methane concentration in the MAN station may be explained form various respects. One of the most important reasons is that the MAN area is under the influence of various source processes relative to all the other stations under consideration. The short-term distribution patterns for the MAN station are hence characterized not only by the high methane concentration but also by the high oscillation in its CH$_4$concentration level.

• Journal of the Korean earth science society
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• 제38권1호
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• pp.24-34
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• 2017

The westerly waves generation is described in the advanced earth science textbook used at high school as follows: as westerly wind approaches and blows over large mountains, the air flow shows wave motions in downwind side, which can be explained by the conservation of potential vorticity. However, there has been no case study showing the phenomena of the mesoscale westerly waves with observational data in the area of small mountains in Korea. And thus the wind speed and time persistency of westerly winds along with the width and length of mountains have never been studied to explain the generation of the westerly waves. As a first step, we assured the westerly waves generated in the downwind side of Sobaek mountains based on surface station wind data nearby. Furthermore, the critical or minimum wind velocity of the westerly wind over Sobaek mountains to generate the downwind wave were derived and calcuated tobe about $0.6m\;s^{-1}$ for Sobaek mountains, which means that the westerly waves could be generated in most cases of westerly blowing over the mountains. Using surface station data and 4-dimensional assimilation data of RDAPS (Regional Data Assimilation and Prediction System) provided by Korea Meteorological Agency, we also analyzed cases of westerly waves occurrence and life cycle in the downwind side of Sobaek mountains for a year of 2014. The westerly waves occurred in meso-${\beta}$ or -${\gamma}$ scales. The westerly waves generated by the mountains disappeared gradually with wind speed decreasing. The occurrence frequency of the vorticity with meso-${\beta}$ scale got to be higher when the stronger westerly wind blew. When we extended the spatial range of the analysis, phenomena of westerly waves were also observed in the downwind side of Yensan mountains in Northeastern China. Our current work will be a study material to help students understand the atmospheric phenomena perturbed by mountains.

• Journal of Korean Academy of Nursing
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• 제22권1호
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• pp.49-67
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• 1992

Most hospitalized children will experience physical pain as well as psychological distress. Preschool children's pain perception related to painful procedures can increase due to elevated anxiety and fear because they do not have understanding logical of their disease and hospitalization. In particular, they are distressed about needle - related procedures which are feared because they are seen to be a cause of bodily damage. This descriptive study attempted to identify pain perception levels in preschool children and their mothers. A self-reporting measurement and behavioral observation were used to collect the data. A total of 25 hospitalized preschool children and their mothers were investigated and data were collected about 60 painful procedures. Data collection was carried out by the researcher and two trained investigators from November first to December tenth. Three insruments were used to collect the data : Faces Pain Rating Scale(FPRS) developed by Beyer was used to measure the degree of preschool children's pain perception about painful procedures. The Visual Analogue Scale(VAS) devised by Huskisson was used to assess the degree of mothers' pain perception about their children's painful procedures. A Pain Behavioral Checklist based on the Procedure Behavior Check List by LeBaron and Zelter and modified by the researcher was used to observe behaviors of preschool children, their mothers, and nurses when the painful procedures took place. The data were analyzed by an SPSS program, and were tested using real numbers, percentages, Pearson correlation coefficient, t-test, and ANOVA. The results of this study are as follows : 1. Of all the painful procedures, the mean score for the FPRS for the preschool children's pain perception was 4.02 points, and the mean score for the VAS of mothers' pain perception was 10.92 points. 2. A Positive correlation which was statistically significant was found between the pain perception of preschool children and their mothers (r＝.53, p＜.01). that is, the higher the children's pain perception was, the higher their mothers' pain perception was. 3. The characteristics of the painful procedures related with children's pain perception as follows : The type of painful procedure was found to be statistically significant (F＝23.44, p＜.01), Among the three procedures Ⅳ starting was found to be perceived as the most painful procedures to the children. The greater the number of times that the procedure had been done, the higher the pain perception was (F＝4.44, p＜.01), and the longer the duration of the procedure, the higher the pain perception wa(r＝.30, p＜.05). Pain perception in the treatment room was higher than in the children's room(t＝6.30, ＜.01), pain perception in the mother's presence was the higher than when the mother was not present (t＝2.91, p＜.01). 4. The characteristics of the painful procedures related with the mothers' pain perception as follows : The type of painful procedure was found to be statistically significant(F＝6.01, p＜.01). Among the three procedures Ⅳ sampling was found to be perceived as the most painful procedures to the mothers. The greater the number of times that the procedure had been done, the higher the pain perception was (F＝5.95, p＜.01), and the longer the duration of the procedure, the higher the pain perception was (r＝.31, p＜.05). Pain perception in the treatment room was higher than in the children's room (t＝3.51, p＜.01), but pain perception in the mother's presence showed statistically significant no difference. 5. Of all of the 19 children's behaviors during the painful procedures, the most frequent behaviors observed Were as follows in order of frequency “crying”, “screamirig”, “facial grimacing”, “physical resistance”, Of all of the nine methers' behaviors, the most frequent by observed in “console children”, “hold children”, “applaud children”, Of all of the 11 nurses' behaviors during the painful procedures, the mast frequent in order were “smiling”, “physical restraint”, “console children”, “praise children”. 6. A positive correlation between children's and mothers' pain perception and children's behaviors was found to be statistically significant (r＝.65, p＜.01, r＝67, p＜.01). Also the relationship between children's and mothers' pain percertion, and mothers' behavior was found to be statistically significant (r＝.57, p＜. 01, 4＝.60, p＜.01). The relationship between children's pain perception and nurses' behaviors was also found to be statistically significant (r＝.46, p＜.01), but there was difference between mothers' pain perception and nurses' behaviors.

• Journal of Korean Academy of Nursing Administration
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• 제3권2호
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• pp.41-59
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• 1997

This study surveyed nurses' value of reward and recognition level of organizational reward, and measured the fit of both. It also looked into the relationship between the reward fit and attitude of nurses toward their job and organization (job involvement${\cdot}$organizational commitment). It was planned to suggest the alternative of a future reward system. The sample consisted of 625 nurses of 8 private University Hospitals. Data for this study was collected from Mar. 25 to Apr. 17 by structured questionnaire. This study examined the differences of nurses' value of reward by their demographic characteristics, and looked into the relationship between the reward fit and job involvement${\cdot}$organizational commitment. Four instruments and a demographic questionnair were used to collect the data. Developed for myself and repaired by panel of judges, the value of reward scale and organizational reward scale consisted of 34 items on five points Likert-type scale. Developed by Kanungo and repaired by panel of judges, the job involvement scale measured overall job involvement on 7 items. The organizational commitment scale was developed by Mowday et al and repaired by panel of judges on 10 items. The data was analyzed by frequency, percentage, ranking, one-way ANOVA, Pearson's correlation coefficient, Chronbach alpha coefficient, t-test, SNK test, factor analysis with SPSS/PC+ progra,.Major findings are as follows 1. The mean of nurses' value of reward is 4.2435 and job content rewards are seen as the most important(M=4.5532). The following orders are seen as follows; financial rewards(M=4.4181), human realtion rewards(M=4.4130), establishment ${\cdot}$ facilities rewards(M=4.1632), professional rewards(M=4.1117), social status or prestige rewards(M=3.9228), career rewards(M=3.8816). Of 34 indivisual reward factors, the retainment allowance is seen to be thought of as the most important thing. 2. The mean of nurses' actual reward is 2.6035. The actual reward responded to the most extremely offered is job content rewards. The following orders are seen as follows ; human relation rewards(M=2.9420), financial rewards(M=2.7682), professional rewards(M=2.4601), social status or prestige rewards(M=2.3696), career rewards(M=2.3466), establishment ${\cdot}$ facilities rewards(M=1.9364). Of 34 indivisual reward factors, medical insurance benefits are felt to be most extremely offered. 3. The mean of fit of reward is -1.6874 and that means actual reward doesn't egual the value of the reward. What is offered mostly to nurses' value of reward is human relation rewards. The following orders are seen as follows; job content rewards(M=-1.5938), career rewards(M=-1.6381), social status of prestige rewards(M=-1.6382), financial rewards(M=-1.6836), professional rewards(M=-1.6854), establishment${\cdot}$facilities rewards(M=-2.3130). Of 34 indivisual factors, the item of fered most closely to nurses' value of reward is seen as the participation in educational programs at the nursing department of the hospital. 4. The mean of nurses' job involvement is 3.1987 and SD is 0.5667. 5. The mean of murses' organizational commitment is 2.9348 and SD is 0.6124, that is seen as a little lower than job involvement. 6. Significant value of reward differences were found among nurses by their demographic characteristics such as married status, tenure, academic career. 7. The fit of reward was significant related to job involvement and organizational commitment. When generalizing the result of this study, the value of reward, which nurses consider important and appropriate offers a reward that corresponds to the nurses' value of reward. This increases nurses' job and organization devotion further, as well as hospital effectiveness. It appears that nurses have recognized that the present reward offered in hospitals doesn't come up to their expectations so I think it is urgent to plan and perform the new reward system which is in accord with the nurses' reward fit.

• The korean journal of orthodontics
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• 제34권2호
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• pp.177-188
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• 2004

This study is aimed at providing the variables associated with adolescent compliance In orthodontic treatment, and identifies the salient predictors of cooperative behaviors over the course of treatment. Orthodontic attitude scale, orthodontic locus of control scale and demographics data were obtained for 60 adolescent orthodontic patients who had been in treatment a minimum of 10 months. This data was then analyzed in relation to their sex, school age and treatment compliance. The following results were obtained. 1. The scoring of external-powerful others-parents, subscale of the Orthodontic Locus of Control scale, found a statistically significant difference between sex differences (p<0.05). The score of boys was higher than that of girls. 2. The external-powerful others-parents score from the Orthodontic Locus of Control scale showed a significantly positive correlation (p<0.05) with the level of compliance. 3. The salient factors associated with compliance were the adolescent patients' own cognition and decisions. 4. There was a statistically significant correlation between the length of treatment and patient compliance (p<0.05). Thus, there was a substantial decrease in the cooperation of orthodontic patients over time. 5. Other independent variables including age, sex, family environment, religion, academic standing, parents' occupation and education, and brushing frequency were investigated and did not yield any significant relationships. Patient compliance is a critical factor in the efficacy of orthodontic treatment. Individuals vary greatly in their perceptions and attitudes of orthodontic treatment, sociodemographic environments and personality characteristics. In assessing the level of compliance attainable by each individual patient it is advisable To pay sufficient attention not only to the technical matters but also to the psychologic aspects of the treatment progress.

• The Journal of Korean Academy of Prosthodontics
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• 제43권2호
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• pp.158-175
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• 2005

Statement of problem. Every effort has been continually made to obtain objectivity in measuring the longevity of fixed restorations, such as by establishing unified judgement standard for deciding success and adopting statistical method that analyzes the data of successful and failed cases at the same time. In Korea, however desired level of development has not to be made in this field yet. Purpose. This study, adopting California Dental Association (CDA) quality evaluation system, established objective standard for deciding success, and inferred the longevity of fixed restorations and their failure analysis through adopting Kaplan-Meier survival analysis. Material and method. In order to assess the longevity of flxed restorations serviced in Korea and causes of failure, a total of 1109 individuals (aged 15-74, 716 women and 393 men loaded with 2551 unit fixed restorations, and 1934 abutments) who lived in Kyung-In Province were examined and the findings were as follows : Results. 1. Length of service of fixed restorations serviced in Korea was 6.86$\pm$0.15 yr (mean), 5.5 yr (median), and the rate of success was 65.82% in 5 year survival, and 21.15% in 10 year survival. 2. When there was patient's need for replacing old prosthetics, longevity of fixed restorations was 7.51$\pm$0.27 yr (mean), 7 yr (median), and the rate of success was 61.08% in 5 year survival, and 17.57% in 10 year survival. 3. Longevity of fixed restorations was longest in the over-sixty age group(9.21$\pm$0.66) and that of the teen age group(3.39$\pm$0.28) was shortest (p<0.05). 4. Longevity of fixed restorations of women (7.38$\pm$0.18 years) was longer than that of men (6.00$\pm$0.26) (p<0.05). 5. As for the provider factor (such as unlicensed performers, university hospitals, and private clinic), there was no statistically significant difference in longevity of fixed restorations. 6. Defective margin (34.78%). periodontal disease (12.15%), periapical involvement (11.73%), was the most frequent causes of failure and poor esthetics group showed the longest life above all (p<0.05). Actual frequent causes of failure after removing old prosthetics were defective margin, periapical involvement, periodontal disease and uncemented restoration. In 75.67% of the cases, abutment state after removing old prosthetics was good enough for loading another prosthetics. 7. There was found to have statistically significant influence between longevity of single crown (6.35$\pm$0.20 yr) and that of 3 unit fixed restorations (7.60$\pm$0.30 y) (p<0.05). In each case the most frequent cause of failure was defective margin. 8. The number of cantilever pontic, pontic/abutment ratio, oral hygiene status were found to have no statistically significant influence on longevity of fixed restorations in all groups (p>0.05). 9. Longevity of fixed restorations made of non precious metal was longest (9.60$\pm$0.40 yr) semi precious and precious trailing behind(p<0.05). 10. Group function group (37.04%) and partial group function group (44.62%) were predominant in frequency but showed no correlation between them and among different types of occlusal plane and different types of occlusal surface (p>0.05). 11. Longevity of fixed restorations was longest in the centric interference group(9.35$\pm$0.62) (p<0.05) among different types of occlusal interference. Conclusion. We found that longevity of fixed restorations serviced in Korea is affected by age, gender and type of material, and that most frequent cause of failure is defective margin. In order to assess the accurate longevity of axed restorations, unified research design. overcoming inter-observer difference and establishing the objective research items are needed. Furthermore, it is thought that prospective approach through thorough study and regular follow-ups is needed just from the start of research. Nationwide detailed studies on length of service of fixed restorations manufactured in Korea are hoped to be conducted hereafter.

• The Journal of Korean Academy of Prosthodontics
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• 제47권4호
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• pp.424-434
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• 2009

Statement of problem: Problems such as loosening and fractures of retained screws and fracture of implant fixture have been frequently reported in implant prosthesis. Purpose: Implant has weak mechanical properties against lateral loading compared to vertical occlusal loading, and therefore, stress analysis of implant fixture depending on its material and geometric features is needed. Material and methods: Total 28 of external hexed implants were divided into 7 of 4 groups; Group A (3i, FULL $OSSEOTITE^{(R)}$Implant), Group B (Nobelbiocare, $Br{\aa}nemark$ $System^{(R)}$Mk III Groovy RP), Group C (Neobiotec, $SinusQuick^{TM}$ EB), Group D (Osstem, US-II). The type III gold alloy prostheses were fabricated using adequate UCLA gold abutments. Fixture, abutment screw, and abutment were connected and cross-sectioned vertically. Hardness test was conducted using MXT-$\alpha$. For fatigue fracture test, with MTS 810, the specimens were loaded to the extent of 60-600 N until fracture occurred. The fracture pattern of abutment screw and fixture was observed under scanning electron microscope. A comparative study of stress distribution and fracture area of abutment screw and fixture was carried out through finite element analysis Results: 1. In Vicker's hardness test of abutment screw, the highest value was measured in group A and lowest value was measured in group D. 2. In all implant groups, implant fixture fractures occurred mainly at the 3-4th fixture thread valley where tensile stress was concentrated. When the fatigue life was compared, significant difference was found between the group A, B, C and D (P<.05). 3. The fracture patterns of group B and group D showed complex failure type, a fracture behavior including transverse and longitudinal failure patterns in both fixture and abutment screw. In Group A and C, however, the transverse failure of fixture was only observed. 4. The finite element analysis infers that a fatigue crack started at the fixture surface. Conclusion: The maximum tensile stress was found in the implant fixture at the level of cortical bone. The fatigue fracture occurred when the dead space of implant fixture coincides with jig surface where the maximum tensile stress was generated. To increase implant durability, prevention of surrounding bone resorption is important. However, if the bone resorption progresses to the level of dead space, the frequency of implant fracture would increase. Thus, proper management is needed.