Objectives : The purpose of this study was to examine the awareness-perception factors and oral health promotion behavior of dental hygiene and nonhealth-related students in an effort to find out factors affecting their oral health promotion behavior. Methods : The subjects in this study were students in the three-year-course dental hygiene and students in the two-year-course nonhealth-related department in G college located in the city of Gwangju. After a survey was conducted, the collected data were analyzed and compared. Results : 1. The dental hygiene students were statistically significantly ahead of the nonhealth-related students in perceived oral health knowledge(p<0.001), awareness of the importance of oral health(p<0.001), perceived oral health status(p<0.001) and oral health interest(p<0.001). 2. Concerning the characteristics of oral health promotion behavior, the dental hygiene students were statistically significantly better at toothbrushing(p<0.001) and the use of dental floss(p<0.001) than the nonhealth-related students. 3. Regarding factors affecting oral health promotion behavior, oral health knowledge and oral health interest were identified as the factors that impacted on oral health promotion behavior. Out of the two, oral health interest exercised a greater influence on that. Conclusions : It seems that oral health education could motivate students to be concerned about their oral health, to acquire knowledge on that and eventually to change their oral health behavior and attitude. As for college students, oral health education provides a final chance for them to check their oral health knowledge, attitude and oral health promotion behavior before they start to work as full-fledged adults, and institutional measures should be taken to offer more intensive official oral health education.

Objectives : This study aims to identify factors affecting satisfaction among the elderly with complete denture to help the elderly with complete denture perform oral hygienic care and to contribute to improvement in oral health. Methods : Interviews were performed with 247 people having complete denture, who were over 65 years and resided in Daejeon and South Chungcheong Province, from March 5 to 31, 2009. Results : 1. As for satisfaction in areas of complete denture by the number of brushing, chewing, pronunciation, and aesthetic functions were all high in over three times of brushing, showing statistically significant differences in satisfaction with chewing (p=0.1825) and aesthetic (p=0.005) functions. 2. As for satisfaction in areas of complete denture by the period of using denture, chewing, pronunciation, and aesthetic functions were all high in less than 7 years, showing statistically significant differences in satisfaction with chewing (p=0.030) and aesthetic (p=0.000) functions. 3. As for satisfaction in areas of complete denture by the subjective oral health state, the better subjective oral health state, the higher satisfaction with chewing, pronunciation, and aesthetic functions, showing statistically significant differences (p=0.000). 4. As for relevance between the subjective oral health state and satisfaction with complete denture, there was 30.1% explanation power in satisfaction with complete denture by the subjective health state. Conclusions : As for satisfaction with complete denture among the elderly, more than three times of brushing and less than 7 years of using denture were related to higher satisfaction; the better subjective oral health state, the higher satisfaction with chewing, pronunciation, and aesthetic functions. Therefore, it is necessary to have the elderly with complete denture receive education about oral hygienic care and perform the care at the same time.

Objectives : This study was application problem-based learning(PBL) of performance oral health manage in dental hygiene education. and evaluate on learning effect - learning attitude, student assessment(good or bed). Methods : For this study, we sampled 31 dental hygiene students composed of PBL group, Dept of Dental Hygiene, A college. The period of this study was 1 semester(from september, 2008 to December, 2008). To identify the effect of PBL on learning attitudes, student assessment, we used a t-test and compared pre & post effects of PBL using a paired t-test and General Linear Model(GLM), McNemar test. Results : The results of this study that problem based learning(PBL) for dental hygiene students education was more effective in learning process and effect of PBL rather than direct instruction. students assessment results that problem based learning improves their medicine knowledge and communication. Conclusions : This study suggest that PBL contribute to enhancing learning attitudes, learning effect and solve the real problems through self-directed learning.

Objectives : The purpose of this study was to analyzes the job implementation of dental hygienist at dental hospital(university), dental clinic and general hospital in the city of Gwangju. Methods : The subjects in this study were dental hygienists who worked at dental hospital(university), dental clinic and general hospital in the city of Gwangju. A survey was conducted by post from June 10 to August 10. Out of the collected data, 204 answer sheets were analyzed. Results : 1. 'Medical & Dental history taking', 'Extra & Intra oral examination' and 'Dental hygiene care plane' in dental clinic were significantly higher than dental hospital(university) and general hospital(p<0.001). 'Remove of extrinsic stain' and 'Treatment of hypersensitivity tooth' in dental clinic and general hospital were significantly higher than dental hospital(university)(p<0.001). 'Preventive dental caries treatment' and 'Diet control' were shown the low frequency of job implementation. 2. Almost task elements of dental assistance duty shown that dental hygienists under the 24 years old were significantly higher dental hygienists over the 30 years old(p<0.05) and dental clinic and general hospital were significantly higher than dental hospital(university)(p<0.05) in frequency of job implementation. 3. 'Dental staff supervision', 'Patient management' and 'Dental chart arrangement' shown that dental hygienists over the 30 years old were significantly higher than dental hygienists under the 24 years old in frequency of job implementation(p<0.05). 'Infection control' of dental hygienists over 30 years old was significantly lower than dental hygienists under the 24 years old(p<0.001). Conclusions : The results of this study indicate that a scope of dental hygienists' job need to extend also in order to accomplish a job efficiently, is suggested that the effort is necessary to improve a quality of dental hygienist and to change of recognition of the dentist about dental hygienists' job.

Objectives : The purpose of this study was to examine factors affecting the effective demand of workers for dental treatment in a bid to provide some information on the improvement of oral health. Methods : The subjects in this study were 255 workers who were engaged in the pharmaceutical industry. A self-administered survey was conducted, and the collected data were analyzed by a spss(statistical package for the social science) win 12.0 program to find out their demographic characteristics, oral health awareness, oral health behavior and factors for the choice of a dental institution. Results : 1. Concerning the level of oral health awareness, 47.0 percent were at a low level(0 to three scores), and 35.2 percent were at an intermediate level(four to six scores). 2. As to oral health behavior involving a daily mean toothbrushing frequency, they brushed their teeth 2.65 times per day on the average. The most widely utilized oral hygiene supply was mouth rinse. Regarding oral health status, 53.7 percent weren't in good dental health, and just 23.0 percent got a dental checkup on a regular basis. 45.8 percent of those who didn't get a dental checkup cited time constraints as the reason. 26.0 percent received oral health education, and 91.4 percent were aware of the necessity of a corporate incremental dental care system. 3. Marital status, age and the reliability of dental institutions made differences to their choice of a dental institution. 4. As for the relationship between oral health awareness and the factors for the choice of a dental institution, oral health awareness had a statistically significant positive correlation to the reliability of dental institutions. Conclusions : The above-mentioned findings suggest that oral health education enables workers to have a correct knowledge on oral health, to change their own oral health behavior and to make the right choice of a dental institution in consideration of their oral characteristics. They should be urged to get a regular dental checkup not to develop chronic oral diseases so that they couldn't have to receive first-aid dental treatment. To promote the oral health of workers, oral health care personnels available should be utilized, and the incremental dental care system should be more vitalized to cut down on their effective demand for dental treatment.

Objectives : The purpose of this study was to examine dental hygiene students' image of dental hygienist and factors affecting the image of dental hygienist in an effort to provide some information useful for dental hygiene education. It's basically meant to recreate the image of dental hygienist as a professional. Methods : The subjects in this study were 310 sophomores and seniors who ere selected by convenience sampling from three different three-year-course colleges located in Gyeonggi Province, Chungcheong Province and Gwangju. After a survey was conducted, the answer sheets from 277 respondents were analyzed except for 33 incomplete ones. The collected data were analyzed with a SPSSWIN 17.0 program, and statistical data on frequency and percentage were obtained to find out the general characteristics of the subjects, and another statistical data on mean and standard deviation for each item were acquired to check their image of dental hygienist. Besides, t-test, ANOVA and Kruscal-Wallis test, one of nonparametric test, were utilized to look for connections between their general characteristics and image of dental hygienist. Results : 1. They gave a mean of 3.53 to the image of dental hygienist, which showed that the dental hygiene students took a favorable view of dental hygienists in general. 2. Their response to four items showed that they looked at the image of dental hygienist in a positive manner. The four items respectively described dental hygienists as professionals, as ones who played a crucial role in the improvement of national oral health, as ones with professional knowledge and sophisticated knowhow, and as neat and decent people. And their response to the following five items indicated that they looked at the image of dental hygienists in a negative way. One was that dental hygienists were considered to be dental nurses, and another was that the occupation of dental hygienist was a demanding and stressful job. The third was that there was no single, fixed title to call dental hygienists, and the fourth was that dental hygiene wasn't recognized as an independent area. The fifth was that the social standing of dental hygienists was sort of high. 3. In regard to the impact of the general characteristics of the dental hygiene students on their image of dental hygienist, they had a more favorable image of dental hygienist when they perceived dental hygiene in a more positive manner(p<0.001). Conclusions : In order to boost the image of dental hygienist, the working conditions of dental hygienists should be improved, and educational programs should be prepared to provided them extended continuing educational opportunities. And the kind of educational environments that could nurture dental hygienists who are convinced and have a vision should be created.

Objectives : This purpose of this study was to examine worker's Dental care utilization patterns and its related factors, to prepare basic data for oral health promotion of workers. Methods : The study subject were 1016 industrial workers from7 working places in Gyung-Sang-Buk Do and Daegu-City. Data for this study was obtained by self-administrated questionnaire. The questionnaire consists of general characteristics, yes or no of dental care utilization before six month, purpose of visit, yes or no of dental disease form the results of dental examination screening before one years, yes or no of and patterns dental care utilization of workers with dental disease, etc. The data was utilized using frequency test and $x^2-test$. Results : Rate of dental care utilization was 40% within six month last, among the general characteristics, it were statistically significant that higher age, married state, bad oral health state, high Work period. Rate of dental disease as a result of their dental examination last was 53.1% among the general characteristics, it were statistically significant that enough economic state, bad oral health state, blue collar work type. Dental care utilization's rate of dental disease as a result of their dental examination last was 48.6% among the general characteristics, it were statistically significant that Enough economic state, higher age, married state, high Work period. Conclusions : In order to promote workers of abnormal opinions to take the medical treatment on their dental diseases later dental examination, it is necessary to educate them consistently for the importance of early medical treatment.

Objectives : This study examined the oral health behavior and dental services utilization of adolescents in order to provide information on how to disseminate the correct oral health behavior to the youth and develop programs for the approach. Methods : The raw data of 'The Third 2007 Youth Health Behavior Online Survey' carried out by the Korea Center for Disease Control and Prevention were analyzed. All survey data collected was processed using SPSS ver 17.0 for data analysis as Frequency analysis, chi-square and Logistic regression analysis. Results : 1.The adolescents who have parents with college degree are 70% higher of dental services utilization than the adolescents counterpart(whose parents don't have degrees). And also the adolescents living in cities are 1.3 times higher use of dental services than others living in countries. 2. In case of drinking soda, students having soda 4 days per week on average are 1.2 times higher use of dental services than who don't. 3.The students brushing teeth after lunch are 0.9 times lower use of dental service than who don't. And the students who have tooth ache whenever they have a meal are 1.6 times higher use of dental service than the students who don't have tooth ache. The students who had a dental health education are 1.4 times higher utilization of dental service than who don't. The difference of using dental service between the students who have gum disease and halitosis and the students who don't is almost none. 4. The students who drink alcohol and smoke 10 days more or less a month are 0.8 ~ 0.9 times lower use of dental service than who don't. Conclusions : The rate of utilizing dental service is higher at students who live with parents having college degrees and the more have oral health behavior, the less use of dental service for treatment. We concluded that more educational program should be developed and vitalized so that students can have oral health.

Objectives : The purpose of this study is understanding the behavior of the laborer relating oral health. Oral health is one of the most important requirement in the healthy life of the laborer. Also it is important to supply the welfare of the people. Methods : For this purpose survey to 400 urban laborer was carried out with questionnaire from October to November, 2009. Among them, 346 available responses were analysed with SPSS 12.0 statistic package. Results : The major findings of the study were as follows:First, Monthly income of 76.6 % of the laborer investigated was below 2500,000 won. Second, 56.1 % of the laborer investigated has the experience to visit dental clinic in the last two years. Third, 35.6 % of the laborer investigated has no experience to visit dental clinic in the last three years. Fourth, The average number of absent days due to oral disease were 0.11 day in a year. Fifth, The average number of the days fail to finish the work of the day due to oral disease were 0.32 day in a year. Sixth, 56.5% of the laborer investigated had no experience of oral health education, because of having no chance. Seventh, Factory bulletin and internet service is preferred as the source of the information on the oral health education. Eighth, In order to improve the status of oral health of laborer, periodical oral health examination and oral health education is needed. Conclusions : In order to improve the oral health of laborer, better public health policy is required, and it is made from understanding the behavior of the laborer relating oral health.

Objectives : This study was carried out with the aim of utilizing it as basic data in a plan for oral health promotion by analyzing oral-health awareness in high school students of some districts in our country, and by analyzing physical, mental and social influential factors in oral health, through using OHIP(Oral Health Impact Profile). Methods : It surveyed by carrying out self-administered questionnaire research targeting 536 boy & girl high school students in the 1st and the 2nd grade at 3 high schools in some districts of Gyeonggi Province. Results : 1. As for experience of having not visited dental clinic, a case of having not visited accounted for 32.5%. On the other hand, a case of having visited accounted for 67.5%. As for the appearance of oral health education, only 2.8% responded as saying of having experience. 97.2% responded as saying of having not taken oral health education. 2. As for oral health state perceived by oneself, the response as saying of 'thinking it to be healthy' and that 'there is something wrong' showed the distribution of 34.1% that is the same ratio. As for oral health interest, a case of having a little interest(58.4%) or of being so much interested(12.5%) showed 70.9%. A case of having no special interest(24.8%) or of having no interest at all(4.3%) showed the level of 29.1%.3. As for oral health knowledge, the toothbrushing knowledge was the highest with 4.54 marks out of 6-point perfection. The toothbrush knowledge(4-point perfection) showed low point with 2.05 marks. 4. By gender, a case of men was high in OHIP(Oral Health Impact Profile) for the functional restriction and physical pain. On the other hand, in the remaining sphere, women were indicated to be high in OHIP. The statistically significant difference was indicated in the spheres such as physical pain, psychological discomfort, a drop in psychological ability, a drop in social ability, and social separation. 5. According to oral health state perceived by oneself, a case of thinking it to be healthy was indicated to be high in OHIP for every sphere. A case of thinking it to have gum disease was indicated to be low in OHIP for every sphere. The statistically significant difference was indicated in every sphere except the sphere of functional restriction. 6. As for a factor of having influence upon OHIP according to oral health knowledge, it was indicated that the higher toothbrush knowledge leads to having more influence upon OHIP. Conclusions : It could be known that the oral health knowledge and OHIP are varied as well according to the oral health interest level. Also, the oral health education proper for subjects is not being performed. Even as for frequency of visiting the dentist, a regular visit is failing to be made. In consideration of these points, the diversified and effective educational program is likely considered to be necessarily developed and improved that subjects can have more interest in oral health.

Objectives : In this study, 233 dental hygiene students in Seoul and Gyeonggi areas were surveyed in order to provide the basic data for more effective clinical practice by investigating the stress they experience during the clinical practice and how they cope with stress; Methods : 5 areas in stress factors as environmental factor, interpersonal factor, role and activity, ideal and value, and the amount of BEPSI and 4 areas in their coping methods as problem-oriented, social support, emotion-oriented, and wishful thinking were measured by Liker 5-point scale. Results : 1. The satisfaction level of subjects on their major was the highest as 'generally satisfied (50.6%),' and their satisfaction level of clinical practice was also the highest as 'generally satisfied (32.6%).' 2. The clinical practice stress was 2.76 points on average, and their stress factors were ideal and value (3.18), environmental factor (2.98), role and activity (2,70), the amount of BEPSI (2.55), and interpersonal factor (2.37). And the way how they cope with stress were 3.29 points on average, wishful thinking (3.71), social support (3.36), problem-oriented (3.13), and emotion-oriented (2.95). 3. The clinical practice stress according to clinical training institutions showed significant differences: university dental hospitals and general hospitals (2.83), dental clinics (2.65), and dental hospitals (2.63). 4. The clinical practice stress showed a negative correlation between the satisfaction level of major and the satisfaction level of clinical practice (p<0.01), and the more satisfaction they had in their major and clinical practice, the less stress during the clinical practice. 5. In the correlation between each subordinate factor of the stress in clinical practice and how to cope with it, interpersonal factor and emotion-oriented factor, the amount of BEPSI and wishful thinking showed a positive correlation (p<0.05). Conclusions : In this study, it is necessary to develop clinical practice program that is to increase satisfaction and provide motivation in order to reduce the stress during clinical training.

Objectives : The aim is to examine what a selective factor of dental institution in the elderly is, which can be used as a strategy for vitalizing hospital management, and which difference there is in selection of dental institution according to health-promotion lifestyle. Methods : Questionnaire survey of individual interview was carried out targeting 177 old people in over 65 years old of Jeonju, Iksan, and Gunsan in Jeollabuk-do Province by convenience sampling from August 16, 2010 to August 27. The analysis was performed by using SPSS WIN 12.0 program. Results : 1. The average mark of health-promotion lifestyle in the elderly was 2.69 points. The health responsibility was the highest with 2.91 points. 2. The mark of health-promotion lifestyle was higher in the higher educational level of the elderly(p<0.01), when monthly income is more than 2 million won(p<0.01), and in the better subjective awareness of oral condition(p<0.01). 3. The group with high mark of health-promotion lifestyle regarded reliability(p<0.001), economic efficiency(p<0.01), and facilities & cleanliness(p<0.01) as important factors when selecting dental institution. Conclusions : The development and expansion in health-promotion program targeting the elderly are seen to be necessary that reflect difference by sphere in health-promotion lifestyle. There will be necessity for pursuing even a strategy for the elderly in the group who have relatively low characteristic in the practice level of health-promotion lifestyle. Also, given understanding characteristics on the elderly and focusing on management proper for the needs of medical consumers, the successful medical management is thought to be likely possible.

Objectives : This research identified the attitude towards senior citizens targeting the workers of the facility for senior citizens to establish Long-Term Care Insurance System early on, and to identify the degree of perception on the importance of senior citizens' oral health and on the need for dental sanitation specialists. Methods : This research targeted 233 workers of the facility for the senior citizens located in some parts of the Gyeongnam area. Survey was conducted from December 1, 2009 to January 31, 2010 to identify the facility workers' attitude towards senior citizens and on the perception towards Long-Term Care Insurance System. Results : 1. As for the awareness towards senior citizens, 50.2% said that they are comfortable around senior citizens while degree of kindness towards senior citizens was 48.5%. 21.0% had experienced training for senior citizens' oral health management. As for the question on who should serve as the trainer, dental sanitation specialists were citied the most with 47.6%. 29.2% was very interested in the senior citizens' oral health while 83.7% said that oral cavity managers are needed in the facility for the senior citizens. As for the question on who should be in charge, if necessary, dental sanitation specialist was cited the most with 57.9%. 2. Awareness on the Long-Term Care Insurance System, treatment for the oral cavity sanitation by visiting homes and information on the activity of long-term care specialists was high following the experience of training for the senior citizens' oral health management in case of the workers at the senior citizens' facility. This manifested statistically significant difference(p<0.05)(p<0.01). Moreover, treatment for oral cavity sanitation manifested statistically significant difference was manifested in the treatment for oral cavity sanitation following the need for oral health managers and who should be in charge, if necessary(p<0.01). Conclusions : These results advocate the need to develop diverse senior citizens' oral health management methods and to continue to carry out actions for senior citizens' oral health improvement that can be carried out by the long-term caretakers for the management of senior citizens' oral cavity health.

Objectives : The objective of this research was to investigate the smoking state of students in Y university, located in Youngdong-gun, Choungbuk. Methods : This research was conducted toward 311 number of students in the university. The questionnaire basically consists of the status of smoking, the behavior of smoker and non-smoker. Results : 58.2% of the male respondents were current smoker, but 72.4% of the females were non-smoker. 58.2% of the current smokers were 22 to 25 aged group. The highest rate of time to begin with smoking was in 15 to 18 years old and the most of people consumed 11 to 20 pieces of cigarettes per day. 48.9% of the students have an experience to keep no smoking more than one month. There were reverse correlation(r=-.335) between the status of smoking and sex, and positive correlation(r=.264) between the status of smoking and an age. Of the people experiencing non-smoking, 55.3% were smoking 'everyday' and 44.7% were 'sometimes'. The biggest part of the reason why stopped smoking was for 'the advices of other people'(25.5%), and 'Harm to health' and 'Social atmosphere of non-smoking'(21.3%) were following. Conclusions : In the university students, current smokers among male students were still high smoking rate. Therefore Dental Hygiene students in the same University have to provide the quit smoking education and oral health care methods for current smokers.

Objectives : This study aimed to research subjective recognition of oral health, oral disease prevention, and knowledge of oral health among high school students to provide basic data necessary to develop an oral health education program for helping them prevent oral diseases and improve oral health in the future. Methods : Respondents' general characteristics and knowledge of oral health were estimated at frequency and percentage, and chi-square $(x^2)$ test was carried out to make a comparison for subjective recognition of oral health and oral disease prevention by general characteristics. ANOVA was used to get scores concerning knowledge of oral health care by general characteristics, and Pearson correlation was used to analyze correlation between recognition of oral health, oral disease prevention, and knowledge of oral health. Results : The findings of the study were as follows: 1. The percentage of those who had visited a dental clinic (hospital) within the previous one year (p<0.01) and had a regular oral examination (p<0.05) was higher in female students than in male ones, and percentage of those who had experienced oral health education (p<0.01) and who had regular oral examination (p<0.001) was highest in 11th graders. The percentage of those who used oral health products (p<0.01) and had pit and fissure sealing (p<0.01) was significantly higher among low-grade students, and the percentage of those who had scaling (p<0.01) was significantly higher among high-grade students. 2. Knowledge of oral health management was higher in female students (12.6) than in male ones (11.2) (p<0.001). Conclusions : A systematic oral health education program is necessary to help high school students improve recognition, prevention, and knowledge concerning oral health care, and continuous attention and efforts must be given to activate continuous oral health care implemented at the elementary level by inducing secondary school students to go on with it.

Objectives : The purpose of this study was to examine the knowledge of dental hygienists on infection control in dental office and their attitude toward that in a bid to provide some information on ways of enhancing the level of infection control in dental office. Methods : The subjects in this study were 220 dental hygienists who worked in dental hospitals and clinics in Busan and South Gyeongsang Province. A survey was conducted from May 17 to June 17, 2010, and the answer sheets from 183 respondents were analyzed with a SPSS WIN 12.0 program. Statistical data on frequency, percentage and mean were obtained, and t-test, Pearson correlation coefficient and one-way ANOVA were utilized. Results : They got a mean of $4.59{\pm}.68$ in six categories of infection control knowledge. They had the best knowledge on dental waste disposal, followed by hand washing, post-sterilization management, instrument disinfection and sterilization, surface management of dental equipment and wearing personal protective equipment. They got a mean of $3.99{\pm}.54$ in attitude, and they scored lowest in practice of surface management of dental equipment. Overall, they scored higher in every aspect of knowledge than in attitude(t=11.410, p=.0.000). There was the greatest gap between their knowledge and practice in surface management of dental equipment (t=13.885, p=0.000), and there was the smallest gap between their knowledge and practice in hand washing(t=5.460, p=0.000). And a positive correlation was found between knowledge and attitude, as better knowledge of infection control led to better attitude toward that(p<.001). Finally, concerning infection control knowledge and attitude by general characteristics, the presence or absence of infection control guidelines made differences to infection control knowledge, and infection control attitude was statistically significantly different according to infection control education experiences(t=6.501, p=.012) and the presence or absence of infection control guidelines(t=22.836, p=.000). Conclusions : In order to bolster infection control in dental office, the related system should be improved to legally require dental personnels to implement infection control. Every dental office must be furnished with infection control guidelines, and sustained education should be provided for dental hygienists to carry out infection control.

Objectives : The purpose of this investigation was to evaluate the remineralization and acid resistance in fluoride varnish by Micro-computed tomography (micro CT). Methods : Specimens of bovine teeth enamel were embedded in resin, polished and randomly divided into 3 groups (a control group, a NaF solution group, a fluoride varnish group). Each group has 3 specimens that was standardized according to Vickers hardness number (VHN). Specimens were immersed in demineralization solution for 72 hours. The control group had no treatment, the NaF solution group was treated by a 5% NaF solution for 4 minutes, and the fluoride varnish group was treated by a fluoride varnish for one hour. All specimens were subjected to a chemical pH cycling method for 14 days. After a chemical pH cycling method, the density were measured using micro CT. Then, specimens were immersed in each demineralization solution for 72 hours. After demineralization processed, the density were measured using micro CT. Results : 1. The density was significantly higher in the fluoride varnish and 5% NaF solution group than that of the control group after 14 days cycling (p<0.05). And the density value of the fluoride varnish group was higher than that of the 5% NaF solution, with no significant difference. 2. The differences of density after acid resistance treatment were statistically significant among 3 groups(p<0.05). Conclusions : It is suggested that fluoride varnish showed the remineralizing effect and acid resistance effect on the enamel, and micro CT could be used to evaluate the change of enamel lesion.