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Effects of Boostin-250 Supplementation on Milk Production and Health of Dairy Cows (재조합 Bovine Somatotropin 250 mg 제제의 투여가 젖소의 산유량 및 건강에 미치는 영향)

  • Kim, Yo-Han;Kim, Doo
    • Journal of Veterinary Clinics
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    • v.29 no.3
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    • pp.213-219
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    • 2012
  • The recombinant bovine somatotropin (rbST) has been used for increasing milk production of dairy cows without adverse health effects. This study was conducted to compare effects of supplementation with $Boostin^{(R)}$-250 containing 250 mg of rbST on milk production with those of $Posilac^{(R)}$ and $Boostin^{(R)}$-S. And safety of rbST supplementation on target animals was also observed. Each twenty-five lactating dairy cows were assigned randomly to one of four groups. $Boostin^{(R)}$-250 and vehicle (control) were administered weekly. $Boostin^{(R)}$-S and $Posilac^{(R)}$ were administered two week intervals. Milk yield, milk components, milk somatic cell count, health status, and body condition score of cows were examined. Supplementation with $Posilac^{(R)}$, $Boostin^{(R)}$-S, and $Boostin^{(R)}$-250 induced more milk yield than control group by 2.9 kg/day (12.3%), 4.2 kg/day (17.9%), and 4.1 kg/day (17.4%), respectively. There was a significant difference in milk yield among three rbST treatment groups and control group (${\alpha}$ = 0.05). The rbST supplementation did not increase the incidence of clinical mastitis and milk somatic cell counts. Supplementation with rbST did not significantly affect milk components (milk fat, protein, and solid not fat). The rbST supplementation of the dairy cows after peak milk yield did not cause negative effect on BCS. However, some cows less than 100 days in milking had decreased BCSs after rbST supplementation. In conclusion, milk production in 250 mg of rbST administered cows every week was similar to that of 500 mg of rbST administered cows every 2 weeks. And supplementation of 250 mg of rbST every week could reduce metabolic stress in cows.

Knowledge, Attitude & Practice for Sexuality of Teachers -Based on over 50 year old teachers- (교사의 성 지식.태도.실태 연구 -50세 이상 교사를 중심으로-)

  • Lee, Eun-Jung;Park, Young-Soo;Choi, In-Sook
    • The Journal of Korean Society for School & Community Health Education
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    • v.5
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    • pp.107-122
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    • 2004
  • To correctly plant the value of sex to the juvenile, we cannot overemphasize the importance of the sexual education in schools. Therefore, the study for teachers' consciousness and view of sex is also necessary, because they are subjects of education and role-models of sex of their students. Especially, if teachers are over fifty in age, it is more important, because it is obvious, as they are in positions of managers and directors of education, that their view of sexual value and consciousness are influencing the aim of education and the course of education. Hereby this study was conducted to check their sexual consciousness, attitude, and condition and to prepare for the basic data needed for the development of a sexual education program suitable to them. The methods of the survey of this study are applied by modifying or supplementing those of precedented studies. They are used after analyzing reliance of items according to Cronbach's $\alpha$ figure calculating law, and modifying or supplementing items lower in reliance. The questionnaire survey was conducted among 1,000 randomly selected from teachers working in middle and high schools in Korea from June 14th in 2004 to June 30th. The survey analyzed 632 questionnaires suitable to it. The outcomes of the survey of this study are like the following: First, the objects of the survey consist of 64.6% men and 35.4% women. Among them, 41.1% are under fifty and the rest are over fifty. As for the periods of marriage, 15.5% are unmarried, 16.3% are under ten years, 18.0% are between ten and twenty, and 50.2% are over twenty. Second, with reagard to sex, 25.6% admit the necessity of a heterosexual friend. 32.0% say that they are conservative to sex. 54.1% are taught sexual education. 67.1% attribute sexual education to nursing teachers. Third, among those who answer that they enoughly know the concept of sex, seenig by age, 25.0% are under fifty and 58.1% are over fifty. Seening by the periods of marriage, 9.2% are unmarried, 28.2% are under ten, 49.1% are between ten and twenty, and 59.0% are over twenty. Among those who answer that they enoughly know the concepts of sexual harassment and sexual violence, seenig by age, in the turns by above-mentioned order, each 47.7% and 76.3%. Seening by the periods of marriage, each 9.2%, 28.2%, 49.1%, and 59.0%. Fourth, among those who answer that "teachers also need sexual education and sexual counsel," by age, each92.7% and 91.4%. By the periods of marriage, each 89.8%, 95.2%, 89.4%, and 92.4%. As a matter of course, we can infer the necessity of the sexual education and sexual counsel for teachers. Fifth, among those who answer that they are satisfied with their sexuality, by age, each 41.1% and 61.3%. By the period of marriage, each 4.1%, 63.1%, 64.1%, and 61.5%. As for the sexual desire like spiritual intercourse, physical intercourse containing sexuality, by age, each 71.9% and 93.5%. By the periods of marriage, each 54.0%, 81.5%, 90.3%, and 93.0%. The survey shows that those over fifty and having long marriage are feeling the stronger desire towards sexuality. Through the outcomes of this survey, a few suggestions are possible: First, it is necessary to check of the teachers' view of sexual value and to study deep about the sexual tendency of them in twenties, thirties, and forties. It is to make them teach their students on the firm basis, and also to develop suitable sexual education and counsel program.

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A Study on Influencing Factors in Health Promoting Lifestyles of College Students (대학생의 건강증진 생활양식과 관련요인 연구)

  • Park, Mi-Yeong
    • Research in Community and Public Health Nursing
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    • v.5 no.1
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    • pp.81-96
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    • 1994
  • The primary purpose of this study was to identify factors affecting health promoting lifestyles of college students on the basis of Pender's Health Promotion Model. The subjects were 1,159 students of one university in Seoul. These data were collected by self reporting questionnaire from April 19 to May 3, 1993. This study examined health promoting lifestyles, cognitive-percep-tual factors: perceived health status, perceived importance of health, health locus of control, and health conception, and modifying factors: sex, grade, major, residence type, and attendance at a health care course. The instruments used in this study were Health Promoting Lifestyle Profile by Walker et al. (1987), Health Value Scale by Wallston et al. (1976), Health Locus of Control by Wallston et al. (1978), and Health Conception Scale by Laffrey(1986). The data were analyzed by Cronbach's $\alpha$, mean, standard deviation, percentage, t-test, ANOVA, Pearson's Correlation Coefficient, and Stepwise Multiple Regression with SPSS PC+ Program. The results were as follows : 1. The means of health promoting lifestyles revealed total 3.33, self actualization 3.74, health responsibility 2.72, exercise 2.80, nutrition 3.55, interpersonal surpport 3.76, and stress management 2.96. Interpersonal support showed the highest score and health responsibility showed the lowest score. 2. No significant differences between sex, grade, major, and residence type, and health promoting lifestyles Were founded(p>.05). Attendants at a health care course showed a significant higher score than nonattendants (p<.001). Male showed a significant higher score in exercise subscale, female showed significant higher scores in health responsibility, nutrition, interpersonal support, stress management subscales(p<.001), residence type showed a significant difference in nutrition subscale(p<.001). 3. No significant differences between perceived health status and sex, grade, major, residence type, and attendance at a health care course were founded(p>.05). Perceived importance of health showed no differences among sex, grade, major, and residence type(p>.05), showed only in attendance at a health care course (p<.001). Attendants at a health care course showed a significant higher score than nonattendants(p<.001). No significant differences between health conception and sex, grade, major, and residence type were founded (p>.05), only significant difference between health conception and attendance at a health care course was founded(p<.05). Nonattendants showed a significant higher score in clinical health conception, attendants showed a significant higher score in wellbeing health conception(p<.05). 4. A significant positive correlation between health promoting lifestyles and perceived health status was founded(r=.2415, p<.001). A significant positive correlation between health promoting lifestyles and perceived importance of health was founded (r=.1475, p<.001). The health promoting lifestyles revealed significant positive correlations in internal and powerful others locus of control (r=.3187, p<.001: r=.1475, p<.001), but revealed a significant negative correlation in chance locus of control(r=-.997, p<.001). A significant positive correlation between health promoting lifestyles and clinical health conception and wellbeing health conception were founded (r=.1241, p<.001 : r=.3047, p<.001). 5. Perceived health status was the highest factor predicting health promoting lifestyles of college students(R=.3415, $R^2=11.62$). Perceived health' status, perceived improtance of health, internal locus of control, wellbeing health conception, powerful others locus of control accounted for 28.19% in health promoting lifestyle patterns. In conclusion, college students who reported more helath promoting lifestyles evaluated their health positively, perceived importance of health highly, perceived their health as affected by theirselves, powerful others but not by chance or luck, and accepted health as high level wellness rather than merely the absence of illness. Those who attending at a health care course had healthier lifestyle patterns. And attendance at a health care course had significant. correlations in these cognitive-perceptual factors. Further studies are required to identify reasons of attending a health care course, and to compare health promoting lifestyles pre-post attending a course related to health care.

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The study of growth and characterization of CuGaSe$_2$ single crystal thin films by hot wall epitaxy (HWE(Hot wall epitaxy)에 의한 CuGaSe$_2$단결정 박막 성장과 특성에 관한 연구)

  • 홍광준;백형원
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.10 no.3
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    • pp.189-198
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    • 2000
  • The stochiometric mixture of evaporating materials for the $CuGaSe_2$single crystal thin films were prepared from horizontal furnace. Using extrapolation method of X-ray diffraction patterns for the polycrystal $CuGaSe_2$, it was found tetragonal structure whose lattice constant $a_0}$ and $c_0$ were 5.615 $\AA$ and 11.025 $\AA$, respectively. To obtains the single crystal thin films, $CuGaSe_2$mixed crystal was deposited on throughly etched GaAs(100) by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were $610^{\circ}C$ and $450^{\circ}C$ respectively, and the growth rate of the single crystal thin films was about 0.5$\mu\textrm{m}$/h. The crystalline structure of single crystal thin films was investigated by the double crystal X-ray diffraction (DCXD). Hall effect on this sample was measured by the method of van der Pauw and studied on carrier density and mobility depending on temperature. From Hall data, the mobility was likely to be decreased by pizoelectric scattering in the temperature range 30 K to 150 K and by polar optical scattering in the temperature range 150 K to 293 K. The optical energy gaps were found to be 1.68 eV for CuGaSe$_2$sing1e crystal thin films at room temperature. The temperature dependence of the photocurrent peak energy is well explained by the Varshni equation then the constants in the Varshni equation are given by $\alpha$ = $9.615{\times}10^{-4}$eV/K, and $\beta$ = 335 K. From the photocurrent spectra by illumination of polarized light of the $CuGaSe_2$single crystal thin films. We have found that values of spin orbit coupling $\Delta$So and crystal field splitting $\Delta$Cr was 0.0900 eV and 0.2498 eV, respectively. From the PL spectra at 20 K, the peaks corresponding to free bound excitons and D-A pair and a broad emission band due to SA is identified. The binding energy of the free excitons are determined to be 0.0626 eV and the dissipation energy of the acceptor-bound exciton and donor-bound exciton to be 0.0352 eV, 0.0932 eV, respectively.

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A Study on Needs of the Families of Head Injury Patients (두부 손상환자 가족의 간호요구에 대한 연구)

  • Cho Gyoo-Yeong;Park Hyoung-Sook
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.6 no.3
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    • pp.414-433
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    • 1999
  • The purpose of this study is to identify the needs which are perceived by one of the familiy members who have head injury parients by traffic accidents in the intensive care units. Subjects were 70 families members of head injury patients admitted to 2 general hospitals NICU located Pusan city, 1 general hospital NICU located Ulsan city from December 1. 1998 to February 28. 1999. For this study, 70 family members were interviewed with aid of a Likert scale which was developed by researcher for this study. For development of the survey instrument, literature review and open questionnaire technique with family members and the nurses working in NICU. The 50needs-items were classified into 7 groups according to the homogeneity of the items with the support of literature review. For the content validity, the instrument was reviewed by 1 nursing professor and the internal reliability of this instrument was Cronbach alpha=0.94 which is highly accepted. Data was analyzed by a SPSS computer program. Data analysis included frequency. percentage, mean, standard variance and t-test or ANOVA. The results were as followings : 1. The general characteristics of head injury patients shows that the male was 74.3%, the female was 25.7% and age distribution shows that the fifty-fifty nine years was 30%, the highest. Of religion the buddhism was the most, The diagnosis distribution shows that epidural hematoma was 32.9% and subdural hematoma was 24.3%. The mentalility distribution shows that semicoma was 31.4% and stupor was 31.4%. Hemiplegia was 42.9% 2. The general charaterisrics of the family needs of head injury patients shows that thirty-thirty nine years was 31.4%, the highest. sex distribution shows that the male was 20%, the female was 80%. Of religion the buddism was the most. 3. The family needs of head injury patients was $3.03{\pm}0.42$, needs for the information of a patient's condition was $3.65{\pm}0.48$, the highest. And needs for the information of care and treatment was $3.48{\pm}0.48$, needs to be supplied with comfortable facilities for family was $3.04{\pm}0.66$, needs to be participate in a patient's care was $2.90{\pm}0.55$, needs to be informed about the available resources was $2.83{\pm}0.59$, needs to be supported emotionally for family was $2.79{\pm}0.55$, needs for religious assistance was $2.51{\pm}0.85$. 4. Examining the family needs of head injury patients according to patient's characteristics, mentality, plegia degree and operation were shown be variables to make an effect on the needs for the head injury patients family. At all, according to severity of head. injury, the family needs of head injury patients was high. 5. Examining the family needs of head injury patients according to their general characteristics, we could know that religion, job. income were shown to be variables to make an effect on the family needs. Through the examination it can be seen that the characteristics of head injury patients and the family needs of head injury patients. In conclusion, the family needs of head injury patients was almost same the family needs of ICU patients. Therefore we must involve the family's care of head injury patients and we must provide exact and repeated explanation, education and support the family of head injury patients. As this study was resulted in selecting the families admitted to NICU of some general hospital, we couldn't stretch the result in our favor. Therefore, continuous studies are suggested.

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A Study on the Care Needs of Family-Caregivers and the Level of Self Care for Patients of Cerebral Vascular Accident(CVA) (뇌졸중환자의 자가간호 수준과 가족구성원의 간호요구)

  • Cho Young-Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.7 no.2
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    • pp.239-255
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    • 2000
  • The purpose of this study was to explore the care needs of family-caregivers caring for patients with a CVA and the level of self care of the patients. The subjects for the study were 112 patients with a CVA and their caregivers. These patients were seen in a hospital or out-patient-department(OPD) at two oriental medical hospital in Jeonbuk province. The survey instruments used in this study were Kang's ADL checklist for self care of patients and Kim's Likert-style checklist for care needs of family-caregivers to patient with CVA. The survey was conducted from July 4 to August 30, 1999. Internal validity by calculation of Cronbach's alpha was 0.95, which was regarded as high. The survey results were analyzed using the SPSS program, with percentages, means, t-test, ANOVA and Pearson's correlation coefficients. The results of this study are as follows : 1. The level of self care for patients with a CVA was : 1) complete dependence(M=14.9, 13.1%), 2) complete independence(M=23.6, 20.9%), 3) incomplete independence(M=23.9, 21.0%), 4) incomplete dependence(M=26.6, 25.0%), 5) dependence and independence(M=23.0, 20.0%). The items for which there was a high level of self care were : 1) drinking(M=3.62), 2) eating (M=3.25), 3) position returning(M=3.18) : and the items for which there was a low level of self care were : 1) ascending and descending stairs(M=2.08), 2) walking(M=2.47). 3) putting on and taking off trousers(M=2.55). 2. The mean score of the sum of the care needs of the family-caregivers was : 1) need for immediate care and help: 2) need of the way to communicate with patient: 3) need for education and assistance related to physical functional level: 4) need to be informed about the disease, treatment and care: 5) need for social support and consultation: 6) need for appreciation: 7) need for management of nursing problems related to immobility. The highest meed factor was the need for immediate care and help(M=3.47): and lowest need factor was the need for management of nursing problems related to immobility(M=2.80). 3. There were significant differences between the level of care need and general characteristic of the caregivers, there were family-caregivers age(P=0.001), marital status (P=0.276), occupation (P=0.006), monthly income(P=0.000), Patient's relationship to caregivers(P=0.004) and health(P=0.000). 4. There were significant differences between the level of self care and general characteristic of the patients, there were patient paralytic condition(P=0.01), blood pressure(P=0.01), and length of suffering(P=0.03). 5 There were significant differences between the level of care need and the general characteristic factors, which were CVA patient's blood pressure (P=0.05), problem of medical fee (P=0.05). 6. There was significantly correlation with the family-caregivers care need and the level of self care in the CVA patient(r=0.300, P=0.000). As a result, need to promote the level of self care in patients and to meet the care need of family-caregivers for more efficient nursing of CVA patients, is emphasized. Therefore more study is needed on an efficient way to provide rehabilitation and quality nursing interventions for family-caregivers and patients with CVA.

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Composition-Some Properties Relationships of Non-Alkali Multi-component La2O3-Al2O3-SiO2 Glasses (무알칼리 다성분 La2O3-Al2O3-SiO2 유리의 조성과 몇 가지 물성의 관계)

  • Kang, Eun-Tae;Yang, Tae-Young;Hwang, Jong-Hee
    • Journal of the Korean Ceramic Society
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    • v.48 no.2
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    • pp.127-133
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    • 2011
  • Non-Alkali multicomponent $La_2O_3-Al_2O_3-SiO_2$ glasses has been designed and analyzed on the basis of a mixture design experiment with constraints. Fitted models for thermal expansion coefficient, glass transition temperature, Young's modulus, Shear modulus and density are as follows: ${\alpha}(/^{\circ}C)=8.41{\times}10^{-8}x_1+5.72{\times}10^{-7}x_2+2.13{\times}10^{-7}x_3+1.09{\times}10^{-7}x_4+1.10{\times}10^{-7}x_5+1.15{\times}10^{-7}x_6+2.72{\times}10^{-8}x_7+2.41{\times}10^{-7}x_8-1.08{\times}10^{-8}x_1x_2+4.28{\times}10^{-8}x_3x_7-2.02{\times}10^{-8}x_3x_8-1.60{\times}10^{-8}x_4x_5-2.71{\times}10^{-9}x_4x_8-2.19{\times}10^{-8}x_5x_6-3.89{\times}10^{-8}x_5x_7$ $T_g(^{\circ}C)=7.36x_1+15.35x_2+20.14x_3+8.97x_4+13.85x_5+4.22x_6+28.21x_7-1.44x_8-0.84x_2x_3-0.45x_2x_5-1.64x_2x_7+0.93x_3x_8-1.04x_5x_8-0.48x_6x_8$ $E(GPa)=2.04x_1+14.26x_2-1.22x_3-0.80x_4-2.26x_5-1.67x_6-1.27x_7+3.63x_8-0.24x_1x_2-0.07x_2x_8+0.14x_3x_6-0.68x_3x_8+0.29x_4x_5+1.28x_5x_8$ $G(GPa)=0.35x_1+1.78x_2+1.35x_3+1.87x_4+9.72x_5+29.16x_6-0.99x_7+3.60x_8-0.48x_1x_6-0.50x_2x_5+0.08x_3x_7-0.66x_3x_8+0.94x_5x_8$ ${\rho}(g/cm^3)=0.09x_1+0.51x_2-4.94{\times}10^{-3}x_3-0.03x_4+0.45x_5-0.07x_6-0.10x_7+0.07x_8-9.60{\times}10^{-3}x_1x_2-8.20{\times}10^{-3}x_1x_5+2.17{\times}10^{-3}x_3x_7-0.03x_3x_8+0.05x_5x_8$ The optimal glass composition similar to the thermal expansion coefficient of Si based on these fitted models is $65.53SiO_2{\cdot}25.00Al_2O_3{\cdot}5.00La_2O_3{\cdot}2.07ZrO_2{\cdot}0.70MgO{\cdot}1.70SrO$.

Effects of activators contained in adhesives on dentin bond strengths (상아질 접착제에 포함된 활성제의 사용 유무가 자가중합 복합레진의 상아질에 대한 전단결합강도에 미치는 영향)

  • Kang, Hye-Kyung;Shin, Joo-Hee;Suh, Kyu-Won;Ryu, Jae-Jun
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.5
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    • pp.511-519
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    • 2008
  • Statement of problem: An incompatibility between the initiator systems of self-curing composite resins and light-curing adhesives was supposed recently. Purpose: The purpose of the study was to evaluate the influence of activators for self/dual bonding on dentin shear bonding strengths. Material and methods: Fifty human molars were divided into 5 groups. A flat dentin surface was created for each tooth. A self-curing composite resin (Luxacore) was bonded with the following adhesives (n = 10); One-Step, Prime&Bond NT, AdheSE, Prime&Bond NT and AdheSE were also used in combination with activators. Shear bond strengths were measured after 24 hours of water storage. The specimens were loaded in shear in the Instron until failure at a 1 mm/min crosshead speed. Data were compared using one-way ANOVA and Tukey HSD test (${\alpha}$= 0.05). Results: The dentin adhesive systems in order of decreasing median bond strength were One-Step > Prime&Bond NT with activator, AdheSE with activator > Prime&Bond NT, AdheSE. Among adhesives, One-Step had the highest bond strength. Prime&Bond NT with activator had higher bond strengths than Prime&Bond NT that was used alone, and so was AdheSE. Conclusion: Shear bond strengths were increased in Prime&Bond NT and AdheSE when these were used with activators comparing used without activators. But using activators was not effective clinically comparing One-Step.

Effects of laser-irradiated dentin on shear bond strength of composite resin (레이저 처리가 상아질과 복합 레진의 결합에 미치는 영향)

  • Kim, Sung-Sook;Park, Jong-Il;Lee, Jae-In;Kim, Gye-Sun;Cho, Hye-Won
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.5
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    • pp.520-527
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    • 2008
  • Purpose: This study was conducted to evaluate the shear bond strength of composite resin to dentin when etched with laser instead of phosphoric acid. Material and methods: Recently extracted forty molars, completely free of dental caries, were embedded into acrylic resin. After exposing dentin with diamond saw, teeth surface were polished with a series of SiC paper. The teeth were divided into four groups composed of 10 specimens each; 1) no surface treated group as a control 2) acid-etched with 35%-phosphoric acid 3) Er:YAG laser treated 4) Er,Cr:YSGG laser treated. A dentin bonding agent (Adapter Single Bond2, 3M/ESPE) was applied to the specimens and then transparent plastic tubes (3 mm of height and diameter) were placed on each dentin. The composite resin was inserted into the tubes and cured. All the specimens were stored in distilled water at $37^{\circ}C$ for 24 hours and the shear bond strength was measured using a universal testing machine (Z020, Zwick, Germany). The data of tensile bond strength were statistically analyzed by one-way ANOVA and Duncan's test at ${\alpha}$= 0.05. Results: The bond strengths of Er:YAG laser-treated group was $3.98{\pm}0.88$ MPa and Er,Cr:YSGG laser-treated group showed $3.70{\pm}1.55$ MPa. There were no significant differences between two laser groups. The control group showed the lowest bond strength, $1.52{\pm}0.42$ MPa and the highest shear bond strength was presented in acid-etched group, $7.10{\pm}1.86$ MPa (P < .05). Conclusion: Laser-etched group exhibited significantly higer bond strength than that of control group, while still weaker than that of the phosphoric acid-etched group.

The study of shear bond strength of a self-adhesive resin luting cement to dentin (상아질에 대한 자가 접착 레진 시멘트의 전단결합강도에 관한 연구)

  • In, Hee-Sun;Park, Jong-Il;Choi, Jong-In;Cho, Hye-Won;Dong, Jin-Keun
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.5
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    • pp.535-543
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    • 2008
  • Purpose: The objective of this study was to compare the bonding characteristics of a new self-adhesive resin cement to dentin, which does not require bonding and conditioning procedure of the tooth surface, and conventional resin cement. The effect of phosphoric acid etching prior to application of self-adhesive resin cement on the shear bond strength was also evaluated. Material and methods: Fortyfive non-carious human adult molars extracted within 6 months were embedded in chemically cured acrylic resin. The teeth were ground with a series of SiC-papers ending with 800 grit until the flat dentin surfaces of the teeth were exposed. The teeth were randomly divided into 3 experimental groups. In group 1, self-adhesive resin cement, RelyX Unicem (3M ESPE, Seefeld, Germany) was bonded without any conditioning of teeth. In group 2, RelyX Unicem was bonded to teeth after phosphoric acid etching. For group 3, Syntac Primer (Ivoclar Vivadent AG, Schaan, Liechtenstein) was applied to the teeth before Syntac adhesive (Ivoclar Vivadent AG, Schaan, Liechtenstein) and Helibond (Ivoclar Vivadent AG, Schaan, Liechtenstein) followed by conventional resin cement, Variolink II (Ivoclar Vivadent AG, Schaan, Liechtenstein). To make a shear bond strength test model, a plastic tuble (3 mm diameter, 3 mm height) was applied to the dentin surfaces at a right angle and filled it with respective resin cement, and light-polymerized for 40 seconds. All the specimens were stored in distilled water at $37^{\circ}C$ for 24 hours before test. Universal Testing Machine (Z020, Zwick, Ulm, Germany) at a cross head speed of 1 mm/min was used to evaluate the shear bond strength. The failure sites were inspected under a magnifier and Scanning Electron Microscope. The data was analyzed with One way ANOVA and Scheffe test at ${\alpha}$= 0.05. Results: (1) The shear bond strengths to dentin of RelyX Unicem was not significantly different from those of Variolink II/Syntac. (2) Phosphoric acid etching lowered the shear bond strength of RelyX Unicem significantly. (3) Most of RelyX Unicem and Variolink II showed mixed fractures, while all the specimens of RelyX Unicem with phosphoric acid etching demonstrated adhesive failure between dentin and resin cement. Conclusion: Shear bond strength to dentin of self-adhesive resin cement is not significantly different from conventional resin cement, and phosphoric acid etching decrease the shear bond strength to dentin of self-adhesive resin cement.