• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.3
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• pp.211-224
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• 2009

The objective of this study is to examine the condylar surfaces in order to find out the types, the incidence and common occurrence area of the osseous abnormalities of the condyles according to the age, genders and the purpose of CT taking, and to compare those between the groups for TMD diagnosis and the other groups. 3D CT images of 199 patients which were scanned with the $i-CAT^{TM}$ Cone Beam Computed Tomography were collected from Sanbon Dental Hospital of Wonkwang university and the MPR images were transfered to the TMJ mode to be showed serial sagittal images and coronal images. The images were macroscopically examined by three independent observers for the types and incidences of the osseous abnormalities, their common occurrence area and general shapes of the condyles. As a result, type F is most common ever than type N. The common occurrence area in sagittal images is antero-superior and superior area except for type D-C which were showed on postero-superior area commonly. In coronal images, latero-superior and superior area is most common except for type E which were present on mesio-superior and superior area most frequently. The osseous abnormalities of the condyles are more common in TMD diagnosis group except for type D-C, that is type N and type D-C are more common in the other groups. In this study, abnormalities of the condyles are classified into 6 types and it has a common occurrence area each. And TMD diagnosis group shows a tendency to have higher rate for osseous abnormalities except for type D-C.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.3
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• pp.225-235
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• 2009

A common procedure of restoration of endodonticlly treated tooth with fiber-reinforced post is followed by core build-up after post cementation. However, this technique is complex and time-consuming. The aim of this study was to compare fracture strength of premolar, restored with various methods of core fabrications on fiber-reinforced posts and casting metal restoration. Forty five freshly extracted human mandibular premolars were obtained and devided into 5 groups acconding to the type of post and methods of core build-up. In Group A, D.T. $Light-post^{(R)}$ were cemented with $DUO-LINK^{TM}$ and then $LIGHT-CORE^{TM}$ was used for core restoration. In Group B, D.T. $Light-post^{(R)}$ and $DUO-LINK^{TM}$ were used for cementing in the postspace, and $DUO-LINK^{TM}$ was used again for core restoration. In Group C, $Light-post^{(R)}$ bonding and the core build-up were performed simultaneously by using $DUO-LINK^{TM}$. In Group D, $LuxaPost^{(R)}$ was bonded by using $LuxaCore^{(R)}-Dual$. Again, $LuxaCore^{(R)}-Dual$ was used for core restoration. In Group E, $LuxaPost^{(R)}$ bonding and the core build-up were performed simultaneously by using $LuxaCore^{(R)}-Dual$. Axial reduction was formed parallelly as possible and 45 degree bevel was made at buccal occlusal surface. Crowns were fabricated and cemented. Each tooth was embedded in self-curing acrylic resin to the level of 2mm below the CEJ. Specimens were fixed on universal testing machin such that the axis of the tooth was at 45 degree inclination to the horizontal plane, and compressive force was applied at a crosshead speed of 1mm/min until failure occurred. The mean fracture strength was the highest in group A followed by descending order in group B, D, E and C. However, there were no statistically significant differences between groups with regard to the fracture strength. The type of the post or build-up methods of the core does not seem to influence the fracture strength.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.321-328
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• 2012

The purpose of this study was to examine the toothbrushing behavior of the citizens, their use of dentifrice, awareness of the importance of dentifrice purchase and consciousness of dentifrice containing the extract of Chamaecyparis obtusa in the city of Gwangju. It's basically meant to provide some informations on the development of oral health supplies involving dentifrice containing the extract of Chamaecyparis obtusa in that city in an effort to help the city serve as a hub of the dental industry. The subjects in this study were the selected citizens in the city of Gwangju. As a result of analyzing their awareness of the importance of the considerations for the purchase and use of dentifrice, they gave 68.2% overall. They gave the highest marks of 83.3% to the importance of effect. As for the importance of each item, they gave the highest marks of 85.1% to the importance of the prevention of dental caries. Concerning differences in awareness of the importance of the external purchase factors according to age, every age group placed the most importance on inspection by the certification authorities except for those who were in their 40s and 60s, and the respondents who were in their 40s and 60s attached more importance to price than the other items. Regarding differences in awareness of the importance of effectiveness according to age, those who were under the age of 20 gave the highest marks of 79.8% to the importance of dental-caries prevention and whitening effects. As a result of asking them whether they had an intention to use dentifrice containing the extract of Chamaecyparis obtusa if this dentifrice would be developed, 54.6% replied they had the intention. When they were asked another question whether they thought this dentifrice would have an effect on oral health, 55.1% answered they thought so. 33.8% expected this dentifrice to have a primary effect on the prevention of dental caries. Given the findings of the study, full-scale R&D efforts should be directed into the development of dentifrice containing the extract of chamaecyparis obtusa in the future.

• Journal of agricultural medicine and community health
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• v.18 no.1
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• pp.77-91
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• 1993

This study was conducted to assess health medical center utilization pattern and its related factors among the rural inhabitants for the purpose of contribution to establishment of health medical center institutions. A questionnaire survey was carried out for object of 3,754 population of three primary school and three middle school student's parents (total 832 household) in Kyungbook Ulchin Gun rural area from 24 to 28 September, 1990. The summarized result are as follows, Respondents are 60.3% in male, 39.7% in female and 30-40s 81.3% in age, high school graduates 40.3% in education level and a regional medical insurance scheme in 44.1% in forms of health insurance. Recognition for health medical center was showed higher according to high educational, high income level, and short distance for location of health medical center of respondents (p < 0.01). Recognition for health medical center services was showed higher about care of medicaid in medical treatment services and higher preventive vaccination in health prevention services by respondents. Utilization rates of health medical center by out-patient care and preventive care service were 11.1 and 4.5 per 100 persons by year, but admission utilization rate was 34.6 per 10.000 persons by year. Motivations of health medical center utilization were showed a good care(45.7%), a good drugs(45.2%), and nearby health medical center(42.9%). In comparison health service levels of health medical center with general clinic was better (16.3%), similar(38.7%), 7(19.0%), and worse(19.0%) in view of health medical center utilizators. Inconvinience about health medical center utilized was the most higher longtime waiting, the next was limited utilization times. Transportation utilited were on foot(55%), by bus(35.5%), and so on. As mentioned above, there are many inhabitants who less understanding and less acknowledgement about health medical center and even mistake health center for health medical center. Therefore, there must be more information about health medical center. For higher utilization of health medical center, there must be considered expansion of health equipment, facilities, accomplishment with reinforcement of health staffs and efficiency management.

• Journal of dental hygiene science
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• v.11 no.5
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• pp.389-395
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• 2011

The purpose of this study was to examine dental hygiene students' achievement motivation and factors affecting dental hygiene students' achievement motivation by the general characteristics of subjects in this study. The subjects in this study were 450 who were selected by convenience sampling from three different three-year-course colleges. After a survey was conducted, the answer sheets from 421 respondents were analyzed. The collected data were analyzed, which made use of t-test, ANOVA and Kruscal-Wallis test. The findings of the study were as follows. 1. The dental hygiene students investigated got 3.34 in achievement motivation. They got the highest score of 3.78 in the item 'I perform what I have to do with a sense of responsibility.' and they got the lowest score of 2.67 in the item 'I like to do something risky.' 2. Concerning links between their general characteristics and achievement motivation, the students whose academic year was higher(p<0.001) and who had more clinical practice experiences (p<0.01) were better motivated than their counterparts. As to connections between achievement motivation and expected post-graduation length of service, those who replied that they planned to find another job after getting married were better motivated(p<0.05). Regarding relationship between achievement motivation and a will to work abroad, the students who had a stronger will to work abroad were better motivated. 3. As a result of checking the influence of their general characteristics on achievement motivation, stronger motivation was found among the students whose academic year was higher(p<0.01), who intended to work until marriage(p<0.01) and who didn't plan to keep working after marriage(p<0.05) when the other variables were controlled. Therefore dental hygiene students should be taught to look at things positively when they enter college, and they should also be educated to become progressive to keep working for their lifetime instead of just getting a temporary job after graduation.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.4
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• pp.403-415
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• 2009

The purpose of the study is to establish the effect of different abutment shapes and types of cements on the retention of the full veneer casted gold crowns. Metal dies that has the similar shape with the implant abutment were manufactured using a short(5mm) and long(10mm) dies with different convergence angles. Metal dies and gold crowns, which were made from the metal dies, were cemented with Temp-bond, Temp-bond mixed with petroleum jelly, ZPC and Premier implant cement. After that, these were tested for tensile force at the point of separation. The effect of convergence angle changes of different cement types on the retention was studied as well as the effects of the cement type changes with different convergence angles on the retention. In addition, study about the marginal gap of Premier implant cement used for this experiment was conducted. The results are as followed under the in-vitro experimental limits; 1. The retention of the Temp-bond mixed with petroleum jelly decreased as the convergence angle increased, and the retention was weakest among the cements. 2. The retention of ZPC decreased as convergence angle increased. When convergence angle was 5 degrees, ZPC showed stronger retention than Premier implant cement. 3. Premier implant cement had the weakest retention when the convergence angle was 5 degrees but when the convergence angle was 10 degrees, it had the strongest retention. As the angle increased more than 10 degrees, the retention decreased. 4. Premier implant cement showed bigger marginal gap when the convergence angle was 5 degrees than 10 degrees under the experimental condition.

• Journal of Oral Medicine and Pain
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• v.35 no.2
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• pp.123-133
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• 2010

The purpose of this study is to investigate Tension-type headache associated with pericranial tenderness and Headache attributed to temporomandibular joint disorder among Characteristic pain index, Disability points, Chronic pain grade, Depression index, Nonspecific physical symptoms (pain items included), Nonspecific physical symptoms (pain items excluded), Jaw disability score using RDC/TMD Axis II. Eighty five patients who visited the Kyung Hee University Dental Hospital were diagnosed as Tension-type headache associated with pericranial tenderness(n=48) and Headache attributed to temporomandibular joint disorder(n=37) by the International Classification of Headache Disorders, 2nd Edition, and were administered the Korean versions of the RDC/TMD Axis II- Characteristic pain index, Disability points, Chronic pain grade, Depression index, Nonspecific physical symptoms (pain items included), Nonspecific physical symptoms (pain items excluded), Jaw disability score. Then it was analyzed statistically by SPSS(ver. 10.0). T-test, The Wilcoxon-signed rank test and Mann-Whitney U test (p<0.05) were used. There were no significant differences in Characteristic pain index, Disability points, Chronic pain grade, Depression index, Nonspecific physical symptoms (pain items included), Nonspecific physical symptoms (pain items excluded), Jaw disability score between two groups. Tension type headache associated with pericranial tenderness and Headache attributed to temporomandibular joint disorder showed similar Axis II feature. Tension-type headache associated with pericranial tenderness may be related to Headache attributed to temporomandibular joint disorder.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.2
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• pp.119-126
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• 2012

State of problem: Cement-retained implant-supported prostheses are routinely used in dentistry. The use of high strength cements has become more popular with the increasing confidence in the stability of the implant-abutment screw connection and the high survival rates of osseointegrated implants. No clinical data on retention of metal copings using CAD/CAM. To evaluate retention of metal copings using CAD/CAM system bonded to short titanium abutment with four different cements and compare retentive strength of metal copings with sandblasting or without sandblasting before cementation. Forty titanium abutment blocks were fabricated and divided into 4 groups of 10 samples each. Forty metal copings with occlusal hole to allow for retention testing were fabricated using CAD/CAM technology. The four cements were Fujicem(Fuji, Japan), Maxcem Elite(Kerr, USA), Panavia F2.0(Kurarary, Japan) and Superbond C&B(Sunmedical, Japan). The copings were cemented on the titanium abutment according to manufacture's recommendation. All samples were stored for 24h at 37oC in 100% humidity and tested for retention using universal testing machine(Instron) at a crosshead speed of 1.0mm/min. Force at retentive failure was recorded in Newton. The mode of failure was also recorded. Means and standard deviations of loads at failure were analyzed using ANOVA and Paired t-test. Statistical significance was set at P<0.05. Panavia F2.0 provided significantly higher retentive strength than Fujicem, Maxcem Elite(P<0.05). Sandblasting significantly increased bond strength(P<0.05). The mode of failure was cement remaining principally on metal copings. Within the limitation of this study, Panavia F2.0 showed significantly stronger retentive strength than Fujicem, Maxcem Elite(p<0.05). The Ranking order of the cements to retain the copings was Panavia F2.0, Fujicem = Maxcem Elite. Sandblasting significantly increased bond strength(P<0.05). The retentive strength of metal copings on implant abutment were influenced by surface roughness and type of cements.

• Journal of dental hygiene science
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• v.9 no.5
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• pp.497-506
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• 2009

This study was conducted to estimate the dental caries experience, oral hygiene status and the factors influencing the dental disease in the smoking adolescents and to provide the baseline data for managing smokers efficiently. We recruited 156 smokers(male: 106, female: 50) in middle, high school students in 5 day Non-smoking program in seoul city and 176 non-smokers(male: 64, female: 112) by matching method for considering sex and age from June 1 to August 31 2009. Data on general characteristics, basic oral health care, smoking factors, self-efficiency, control of oral health, oral health promotion behavior, knowledge of oral health were collected by a questionnaire interview. DMFT index, DT index, MT index, FT index, Plaque index, Calculus index were calculated by the oral examination. The results of this study were as follows. 1. Dental clinic visit(p < 0.05), self-perception of oral health status(p < 0.001), oral health concern (p < 0.01) in non-smoker group were significantly higher than that of smoker group. 2. self-efficiency(p<0.05), oral health promotion behavior(p < 0.05) in non-smoker group were significantly higher than that of smoker group. 3. DT index, Plaque index, Calculus index in non-smoker group was significantly lower than that of smoker group(p < 0.0001). 4. The fewer smoke amount, the lower DT index(p < 0.05), Plaque index(p < 0.01), Calculus index(p < 0.001). 5. It was significant correlated among DT index and self-efficiency, oral health promotion behavior, control of oral health. 6. In multiple regression analysis, oral health promotion behavior, Plaque index was proved as a significant factors related with the degree of dental caries experience in smoking adolescents. In other word, the higher oral health promotion behavior, the lower Plaque index, the fewer DT index.

• Journal of dental hygiene science
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• v.15 no.2
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• pp.129-137
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• 2015

This study is conducted with the aim of providing basic data for oral health improvement of pregnant woman and development of oral health education program by analyzing factors influencing the oral health related behavior of pregnant woman applying health belief model which is theoretical model of explaining individual's behavior change. For 217 expectant mothers who visited 8 obstetrics and 1 maternity class located in Seoul, Gyeonggi and Incheon from August 1 to 31, 2014, data analysis was implemented using self-administered questionnaire. Before the completion of self-administered questionnaire, the subjects were fully informed of explanatory note and consented on taking part in the research for the consideration of ethical aspect. Collected materials were treated by PASW Statistics ver. 18.0 program and following results were acquired. Health belief factor which infuences oral health related behavior of pregnant woman resulted that perceived severity influences on oral examination during pregnancy and dental treatment during pregnancy, and perceived benefits influences on oral examination during pregnancy, and perceived barriers on toothbrushing after having a snack, toothbrush with rotation method and oral examination during pregnancy, and self-efficacy influences on use of oral hygiene products after toothbrushing and oral examination during pregnancy. With these research results, I suggest that perceived severity of health belief factor, perceived benefits, perceived barrier and self-efficacy influence oral health related behavior of pregnant woman. And specific oral health education program for pregnant woman is necessary to increase perceived severity of pregnant woman, perceived benefits and self-efficacy and to reduce perceived barriers.