• Journal of Technologic Dentistry
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• v.33 no.4
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• pp.349-357
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• 2011

Purpose: In this study, for the reasons of observing the changes when using bonding agent with Ni-Cr alloy and Co-Cr alloy and using VM13 and Vintage MP ceramic which have the disparity in coefficient of thermal expansion, it is carried out to evaluate the characteristics of the bonding agent through the analysis of the interface between metal and ceramic and the analysis of bond strength by variable. Methods: The surface treatment was performed on the two kinds of alloy(Ni-Cr alloy and Co-Cr alloy) specimens, which were sandblasted and were treated with bonder application. The metal-ceramic interfaces were analyzed with EPMA in order to ionic diffusion, and the shear test was performed. Results: As a result of observation of metal-ceramic interfacial properties, it was observed that Cr atoms were spread from the alloy body to the ceramic floor in the specimen of Group B. It was also seen that Cr, W atoms were spread from the alloy body to the ceramic floor in the specimen of Group S. In consequence of observing Shear bond strength, it was calculated that the specimen of BSV was 27.75(${\pm}11.21$)MPa, BSM was 27.02(${\pm}5.23$)MPa, BCV was 30.20(${\pm}5.99$)MPa, BCM was 27.94(${\pm}10.76$)MPa, SSV was 20.83(${\pm}2.58$)MPa, SSM was 23.98(${\pm}3.94$)MPa, SCV was 32.32(${\pm}4.68$)MPa, and SCM was 34.54(${\pm}10.63$)MPa. Conclusion: In the metal-ceramic interface of Bellabond plus sample group, diffusion of Cr atoms was incurred and diffusion of C Cr atoms and W atoms in the sample group of $Starloy{(R)}\;C$ was observed. Using bonding agent showed the higher bond strength than using the sand blasting treatment. In the Bellabond plus alloys, the specimen group with the use of binding materials showed higher shear bond strength, but didn't show statistically significant differences (p>0.05). In the $Starloy{(R)}\;C$ alloys, the specimen group with the use of binding materials showed higher shear bond strength and statistically significant differences(p<0.05). In terms of VM13 ceramic, it was in the Bellabond plus alloys that the high shear bond strength was showed, but there's no statistically significant differences(p>0.05). In terms of Vintage MP ceramic, it was in the $Starloy{(R)}\;C$ alloys that the high shear bond strength was showed and statistically significant differences(p<0.05). Metal-ceramic to fracture of the shear strength measurements and an analysis of all aspects of military usage fracture of the composite, respectively.

• Journal of Technologic Dentistry
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• v.34 no.4
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• pp.447-455
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• 2012

Purpose: This study was to investigate oral hygiene knowledge and the actual condition of oral care for the students in the public health and non-public health Departments. Methods: The survey sample consisted of 262 randomly selected students. 197 of them are public health-related students and 65 are non-public health-related students. The questionnaires used in this study consisted of 4 items for general information, oral health status of 2 items, 5 items for Oral hygiene knowledge and actual condition of oral care of 5 items. Collected data were analyzed by Frequency Analysis t-test and Crosstabs using SPSS(Statistical Package for Social Sciences) Win 19.0 statistics program. Results: Regarding general characteristics of the subjects, there were 53.8% of first-year student, 26.0% of second-year student and 20.2% of third-year student among 52.3% of males and 47.7% of females. The subjects received less than "100,000" won(13.0%), "100,000-190,000" won (5.0%), "200,000-290,000" won(30.9%), "300,000-390,000" won (33.2%) and more than "400,000" won(17.9%) a month for an allowance. The subjects had 'none' (44.3%), '1'(6.5%), '2'(12.6%), '3'(5.0%), '4'(5.3%), 'more than' 5(0.8%) of dental caries and 'do not know' were 25.6%. The numbers of dental prosthetics were 'no' (35.5%), '1'(13.7%), '2'(17.2%), '3'(10.3%), '4'(11.5%), and 'more than 5'(11.8%). The public health students(84.8%) had a higher positive response rate than the non-public health students(66.2%). The public health students(80.2%) had a higher negative response rate than the non-public health students(78.5%) in the result of onset of gum disease pain awareness. The non-public health students(65.5%) had a higher negative response rate than the public health students(68.3%)) in the result of heredity of gum disease. The t-test showed that public health-related department students(M=8.264, SD=0.821) had more knowledge about oral hygiene than non-public health-related department students(M=8.015, SD=1.082). 'do not use' in the oral care products except toothpaste and toothbrush showed that public health-related department students(60.4%) use the products more than non-public health-related department students(66.2%). Conclusion: In this study, public health-related department students had higher oral hygiene knowledge and actual condition of oral care compared to non-public health-related students, but low in practical action. Due to the lower level of dental care products use in non-public health-related department, a continuous oral care education program is required.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.204-209
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• 2003

A 9-year old boy visited Department of Pediatric dentistry, Chonbuk National University Hospital due to unstable occlusion. He had permanent 1st molars destructed severely by dental caries and lost vertical stop. He could not occlude in the same position on closing of the jaw since he could not find his centric occlusion. The treatment plan was made, which was oral rehabilitation with crown restorations on permanent 1st molars based on clinical and radiographic examinations and centric relation of the jaw. Treatment plan consisted of endodontic treatment, crown lengthening and restoration of the occlusal vertical dimension (OVD) with gold crown by 3mm-increase of OVD. After endodontic and periodontal treatments, temporary crowns made of acrylic resin were set for assessment of tolerance to an increased OVD. After a month for tolerance, final prosthetics were made and set temporarily. In a month, gold crowns were set finally. Immediately after setting, the patient showed anterior open bite, but at the appointment after 4 months, he showed normal overjet, overbite and stable occlusion.

• The Journal of Korean Physical Therapy
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• v.14 no.4
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• pp.274-307
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• 2002

The TLSO was customized for this study in OO ortho-prosthesis institute from Jan. 1th., 2000 to Dec. 31th., 2000 and in order to measure effects of TLSO. 20 females in a growth period applicable to medical care took part in this study, they were on accidental spine scoliosis (From $15^{\circ}to35^{\circ}$). They were consisted of Group I(10 chest-bend) and Group II (10 dual-bend). The results were follows: 1. It showed the average difference in height by 1.37cm, 3.14cm in comparison between before and after TLSO, before and after one year and they were also statistically available(p < .05). 2. It showed the average difference in Cobb angle of a chest and waist by ($-10.95^{\circ},-8.50^{\circ}$), between before and right after TLSO. The results means that the Cobb angle of the chest and weist at right after TLSO was largely decreased, and it was also statistically available(p < .05). 3. It showed the difference in Cobb angle of the chest waist by $-9.50^{\circ},-7.35^{\circ} $ between before and one year after TLSO. It means that the Cobb angle of the chest and waist at the one year after TLSO was largely decreased, and it was also statistically available(p < .05). 4. It showed the difference in Cobb angle of the chest and waist by $2.34^{\circ},2.15^{\circ} $ between the right after and the one year after. TLSO, but the change of Cobb angle of the chest was regularly constant by a little increased, and it was also statistically available(p < .05). 5. In the measurement of the change of Cobb angle of the chest and waist according to the taking time on TLSO, it showed the slightest change in 10 people on TLSO for 23 hours by $13.30^{\circ},11.20^{\circ}$ , the change in 6 people on TLSO for 16 hours by $14.75^{\circ},12.67^{\circ}$, the change in 4 people on TLSO for 8 hours by $16.83^{\circ},14.00^{\circ} $ in this order. It means that the longer time on TLSO was to be the smaller the Cobb angle of the chest and waist, but it was not statistically available.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.1
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• pp.35-44
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• 2014

This study was performed to investigate the anti-photoaging effects of Persimmon leaf tea(PLT) in hairless mice(SKH-1) exposed to UVB radiation. The animals were divided into non-treated group (normal, N) and UV-radiated groups. UV-radiated groups were divided into only UV-radiated group(control, C) and UV-radiated and PLT treated experimental groups[first extraction treated group(PLT-I), second extraction treated groupe(PLT-II), and third extraction treated group(PLT-III)]. Three PLT treated experimental groups of mice were treated with both oral administration(300mg/Kg B.W./day) and topical application (100 ul of 2% conc./mouse/day) for 4 weeks. Anti-photoaging effects of Persimmon leaf were evaluated by MTT assay, anti oxidative reaction, MMP immunohistochemistry, gelatin zymography assay and RT-PCR observations. Treatment with Persimmon leaf tea(PLT)-I, and -III groups decreased immunohistochemical density of matrix metalloproteinases(MMP)-3 and -9 related to degradation of extracellular matrix in skin. Especially, immunohistochemical density of MMP-2 decreased in PLT-I, -II and -III groups in skin. On the effects of antioxidant function on the treatment with Persimmon leaf tea(PLT), treatment of HaCaT cells with extracts of PLT-I and PLT-II had also significantly reduced intracellular ROS produced by UVB irradiation in a dose dependent manner(PLT-I, p<0.05, p<0.01, p<0.001; PLT-II, p<0.01, p<0.001). Gelatin zymography assay revealed that PLT-II and PLT-III (200 ug/ml) had inhibitory effect on MMP-9 expression in UVB-radiated HaCaT cells. Western blot analysis revealed that PLT-1, -II and -III groups down-regulates the expression of inflammatory associated genes(IL-$1{\beta}$) and PLT-1 and -II groups down-regulates the expression of TNF-${\alpha}$ in a dose dependent manner. Our study suggests that Persimmon leaf tea(PLT) extracts participates in inhibitory effects on the morphological and molecular experiments related to photoaging skin on UVB irradiated hairless mice.

• Journal of Korean society of Dental Hygiene
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• v.7 no.4
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• pp.481-493
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• 2007

It follows in increase of the old age population and the loss of teeth increases, also the supplement prosthetics treatment which is caused by loss of teeth is various and it develops and the dentistry implant demand is increasing. This study enforced a self-administered survey with 197 dental personnels employed in dental hospitals, dental clinics from August 15, 2007, to September 15, in the area of Daejeon. It's ultimately intended to serve as a basis for the preparation of more effective, appropriate dental implants education programs for personnels, who take a crucial part in dental implants operation, provide better dental services to patients who are in need of dental implants operation. As the result, the study got the following conclusion. 1. The population sociological feature of dental hospital and dental clinic showed that significant differences of dental service career. Dental service career of dental personnels shows; below 3 years 43.1%, 4~6 years 35.3%, more than 7 years 21.6% in dental hospitals, below 3 years 29.5%, 4~6 years 28.1%, more than 7 years 42.5% in dental clinics(p=0.027). 2. The average score of personnels knowledge in dental implants was 3.67point, from analyzing the knowledge on dental implants of dental personnels from dental health-care settings, dental personnels employed in dental hospitals scored relatively higher than in dental clinics(p=0.129). Dental personnels with 4~6 years of experience scored the highest(p=0.002). 3. The average score of dental personnels compliance in dental implants was 3.92point, from analyzing the compliance of dental implants of dental personnels from dental health-care settings, dental personnels employed in dental hospitals scored relatively higher than in dental clinics(p=0.006). Dental personnels with 4~6 years of experience scored the highest(p=0.707). 4. The contingency coefficient between dental implants general knowledge and the general compliance(r=0.233, p=0.001), operation knowledge and operation compliance(r=0.332, p=0.000), maintenance knowledge and maintenance compliance(r=0.236, p=0.001). 5. Recently dental implants is emerging as one of the important medical services in the dental treatment sector. From analyzing the compliance of dental implants of dental personnels in dental health-care settings, dental personnels employed in dental hospitals scored relatively higher than in dental clinics. Consequently, the effort of the dentist and the dental personnels demanded to be earnestly to improves the difference of the knowledge and compliance against the dental implants of the dental personnels in dental health-care settings, it is thought that with reinforcement of effective role share and professionalism to success of dental implants, more system and the specialty dental implants education which is standardized continuously must be provided to all dental personnels.

• Applied Microscopy
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• v.42 no.1
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• pp.9-16
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• 2012

The goal of this study was to identify neurotransmitters in endings (p-endings) presynaptic to low-threshold mechanoreceptive vibrissa afferents in the laminae III/IV of cat trigeminal caudal nucleus (Vc). Rapidly-adapting vibrissa afferents were intra-axonally labeled after electrophysiological identification, and postembedding immunogold staining with antisera against ${\gamma}$-aminobutyric acid (GABA) and glycine was performed, followed by quantitative ultrastructural analysis of p-endings presynaptic to the labeled vibrissa afferent terminals. Sixteen p-endings, which are presynaptic to the HRP-labeled vibrissa afferent terminals, were analyzed in this study: Eight p-endings (50%, 8/16) were immunopositive to GABA but immunonegative to glycine (GABA+ p-ending), and remaining 8 p-endings (50%, 8/16) exhibited immunoreactivity to both GABA and glycine. Bouton volume of the p-endings was not significantly different between the two groups. However, the p-endings differed from each other in relative content of GABA and glycine. These findings suggest that low-threshold mechanoreceptive information conveyed through vibrissa afferent at Vc is presynaptically modulated by GABA and/or glycine, and that degree of presynaptic modulation may differ among each vibrissa afferent terminal.

• Herbal Formula Science
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• v.27 no.4
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• pp.269-284
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• 2019

This study was to investigate whether cultivated ginseng (CG), cultivated wild simulated ginseng (CWG) and cultivated red ginseng (CRG) extracts influences on the obesity. The saponin contents of 3 kinds of ginsengs were analysed by HPLC-ESI-TOF-MS. Total saponin contents were determined in CG on the most contents and since red ginseng has the highest PD (protopanaxadiol type) / PT (protopanaxatriol type) ratio, there may be differences between ginseng, wild ginseng, and red ginseng with respect to their pharmacological effects. Male C57BL/6J mice were fed a normal diet(N), HFD (60% Kcal fat, C), HFD with CG, CWG and CRG extracts (800 mg/kg) for 5 weeks. We observed change of total body weight, degree of hepatic lipid accumulation and immunohistochemical change of GLP-1 and insulin-secreting cells. Also this study attempts to use the physiological analysis method to analyze the changes of blood lipids, insulin and leptin concentration. The change of body weight and size of accumulated lipid droplets in liver lobules decreased in all of the experimental groups than the control(C) group. In the pancreas, the immunohistochemical density of insulin-secreting cells were significantly stronger in the CWG and CRG than C group. The levels of serum insulin and leptin significantly decreased 55.6%, 54.3% respectively in CWG and CRG. The changes of triglyceride, total cholesterol in serum decreased in CRG than the C group. Obesity related CG, CWG and CRG extracts might have contribute to improvement of obesity by regulating the levels of blood lipids and biochemical indicator of fat accumulation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.6
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• pp.379-391
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• 2003

The present study was undertaken to evaluate bone regenerative capacity around titanium screw implants placed in irradiated rat's tibiae. At one week after single 15-Gy dose irradiation, miniaturized titanium screw implants were inserted into anterior aspect of the upper tibia of rats weighing 200-250g. Seventy rats were involved: 35 rats were control and 35 rats radiation group. The rats were killed at different intervals as 1, 2, 3, 4, 6, 8, 12 weeks after implantation for histologic observation, histomorphometric analysis and immunohistochemical study with fibronectin and CD34 antibody. 1. Histologically, various stages of bone maturation and ossification can be seen at 4 weeks and regenerated bone close to edges demonstrates more advanced calcification, and network of new bone are well formed at 12 weeks in non-irradiated group. In contrast, active bone formation with increased contact of newly formed bone to implant surface was noted at 4 weeks and a significant amount of new bone formation and bone-implant contact is oberved at 12 weeks in irradiated group. 2. Histomorphometrical analysis confirmed these histologic findings. A significant difference in implant-bone contact and bone density was measured between the control and radiation group. Mean MBD was 62.2% in control group and 27.5% in radiation group, mean MBIC was 86.6% in control group and 47.7% in radiation group, and mean TBIC was 87.3% in control group and 45.6% in radiation group at 12 weeks after implantation. 3. In immunohistochemical study with fibronectin and CD34, radiation reduced hematopoietic progenitor cells severely and disturbed differentiation of osteoblast in bone marrow. The results of this study revealed bone healing capacity around implant after radiation therapy was severely impaired and irradiation reduces the capacity for osseointegration of titanium implants. Many factors including radiation dose, period between radiation and implantation, bone quality, time elapse between first and second surgery, type of prosthetics and hyperbaric oxygen therapy must be considered carefully in postradiation implantation.

• Physical Therapy Korea
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• v.15 no.1
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• pp.38-45
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• 2008

This study investigated gait characteristics, kinematics, and kinetics in the lower extremities between two different shoe conditions (high heeled shoes (7 cm), and high heeled shoes with a total contact insert (TCI)) after lower extremity muscle fatigue. Although TCI shave been applied in high heeled shoes to increase comfort and to decrease foot pressure, no study has attempted to identify the effects of TCI in fatigue conditions. The purpose of this study was to determine the effects of walking in high heeled shoes with TCI after lower extremity muscle fatigue was induced. This study was carried out in a motion analysis laboratory at Hanseo University. A volunteer sample of 14 healthy female subjects participated. All in fatigue conditions, the subjects were divided into two groups. The muscle fatigue was induced by 40 voluntary dorsi- and plantar-flexion exercises and 40 heel-rise exercises of the dominant foot. Surface electromyography was used to confirm the localized muscle fatigue using power spectral analysis of three muscles (tibialis anterior, gastrocnemius medialis and lateralis). The results were as follows: (1) In muscle fatigue conditions, the use of TCI decreased the peak flexion angle of the hip joint significantly in the early stance phase (p<.05) and increased the peak hip flexion moment in the terminal stance phase (p<.05). (2) In muscle fatigue conditions, the application of TCI also increased peak hip power generation in the early stance phase and peak hip power absorption in the terminal stance phase (p<.05). (3) In muscle fatigue conditions, the use of TCI reduced the impact force significantly and increased the secondary peak vertical GRF. These findings suggest that the TCI may provide beneficial effects when muscle fatigue occurs for a high heeled shoe gait. Future research employing the patient population and various types of TCI materials are required to clarify the effects of TCI.