• Restorative Dentistry and Endodontics
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• v.32 no.3
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• pp.208-221
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• 2007

The fracture toughness test is believed as a clinically relevant method for assessing the fracture resistance of the dentinal restoratives. The objectives of this study were to measure the fracture toughness $(K_{1C})$ and microtensile bond strength of dentin-resin composite interface and compare their relationship for their use in evaluation of the integrity of the dentin-resin bond. A minimum of six short-rod specimens for fracture toughness test and fifteen specimens for microtensile bond strength test was fabricated for each group of materials used. After all specimens storing for 24 hours in distilled water at $37^{\circ}C$, they were tensile-loaded with an EZ tester universal testing machin. Statistical analysis was performed using ANOVA and Tukey's test at the 95% confidence level, Pearson's coefficient was used to verify the correlation between the mean of fracture toughness and microtensile bond strength. FE-SEM was employed on fractured surface to describe the crack propagation. Fracture toughness value of Clearfil SE Bond (SE) was the highest, followed by Adper Single Bond 2 (SB), OptiBond Solo (OB), ONE-STEP PLUS (0S), ScotchBond Multi-purpose (SM) and there was significant difference between SE and other 4 groups (p < 0.05). There were, however, no significant difference among SB, OB, OS, SM (p > 0.05). Microtensile bond strength of SE was the highest, followed by SB, OB, SM, OS and OS only showed significant lower value (p < 0.05). There was no correlation between fracture toughness and microtensile bond strength values. FE-SEM examination revealed that dentin bonding agent showed different film thickness and different failure pattern according to the film thickness. From the limited results of this study, it was noted that there was statistically no correlation between K1C and ${\mu}TBS$. We can conclude that for obtaining the reliability of bond strength test of dentin bonding agent, we must pay more attention to the test procedure and its profound scrutiny.

• Restorative Dentistry and Endodontics
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• v.32 no.3
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• pp.180-190
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• 2007

The purpose of this study was to evaluate the abrasion resistance of surface penetrating sealant which was applied on a composite resin restoration and to provide proper time to reapply sealant on composite resin surface. Two hundred rectangular specimens, sized $8\times3\times2mm$, were made of Micronew (Bisco, Inc., Schaumburg, IL, U.S.A) and divided into two groups; F group (n = 10) was finished with coarse and medium grit of Sof-Lex discs and BisCoverwas applied B group (n = 190) after finishing with discs. B group was again subdivided into nineteen subgroups From B-1 group to B-18 group were subjected to toothbrush abrasion test using a distilled water-dentifrice slurry and toothbrush heads B-IM group was not subjected to toothbrush abrasion test. Average surface roughness (Ra) of each group was calculated using a surface roughness tester (Surfcorder MSE-1700: Kosaka Laboratory Ltd., Tokyo, Japan) . A representative specimen of each group was examined by FE-SEM (S-4700: Hitachi High Technologies Co., Tokyo, Japan). The data were analysed using cluster analysis, paired t-test, and repeated measure ANOVA. The results of this study were as follows; 1. Ra off group was $0.898{\pm}0.145{\mu}m$ and B-IM group was $0.289{\pm}0.142{\mu}m$. Ra became higher from B-1 group $(0.299{\pm}0.48{\mu}m$ to B-18 group $(0.642{\pm}0.313{\mu}m$. 2. Final cluster center of Ra was $0.361{\mu}m$ in cluster 1 $(B-IM\simB-7)$, $0.511{\mu}m$ in cluster 2 $(B-8\simB-14)$ and $0.624{\mu}m$ in cluster 3 ($(B-15\simB-18)$. There were significant difference among Ra of three clusters. 3 Ra of B-IM group was decreased 210.72% than Ra of F group. Ra of B-8 group and B-15 group was increased 35.49% and 51.35% respectively than Ra of B-IM group. 4. On FE-SEM, B-IM group showed the smoothest resin surface. B-8 group and B-15 group showed vertically shallow scratches , and wide and irregular vertical scratches on composite resin surface respectively. Within a limitation of this study, finished resin surface will be again smooth and glazy if BisCover would be reapplied within 8 to 14 months after applying to resin surface.

• Restorative Dentistry and Endodontics
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• v.33 no.4
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• pp.332-340
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• 2008

The purpose of this study was to evaluate the viability of periodontal ligament cell in rat teeth using slow cryopreservation method with magnetic field through MTT assay and TUNEL test. For each group, 12 teeth of 4 weeks old white female Sprague-Dawley rat were used for MTT assay, and 6 teeth in TUNEL test. The Maxillary left and right, first and second molars were extracted as atraumatically as possible under tiletamine anesthesia. The experimental groups were group1 (immediately extraction), group 2 (cold preservation at 4$^{\circ}C$ for 1 week), group 3 (rapid cryopreservation in liquid nitrogen), group 4 (slow cryopreservation with magnetic field of 1 G), and group 5 (slow cryopreservation). F medium was used as preservation medium and 10% DMSO as cryoprotectant. After preservation and thawing, the MTT assay and TUNEL test were processed. One way ANOVA and Scheffe method were performed at the 95% level of confidence. The value of optical density obtained after MTT analysis was divided by the value of eosin staining for tissue volume standardization. In both MTT assay and TUNEL test, it had showed no significant difference among group 3, 4, and 5. And group 3 had showed higher viability of periodontal ligament cell than group 2. From this study, slow cryopreservation method with magnetic field can be used as one of cryopreservation methods.

• Restorative Dentistry and Endodontics
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• v.31 no.4
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• pp.323-329
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• 2006

The aim of this study was to evaluate the retrievability of Resilon as a root canal filling material Twenty-seven human single-rooted extracted teeth were instrumented utilizing a crown down technique with Gates-Glidden burs and ProFile system. In group1 (n = 12) canals were obturated with gutta percha and AH-26 plus sealer using a continuous wave technique and backfilled. In group 2 (n = 15) Resilon was used as a filling material. Then teeth were sealed and kept in $37^{\circ}C$ and 100% humidity for 7 days. For retreatment, the samples were re-accessed and filling material was removed using Gates-Glidden burs and ProFiles. Teeth were sectioned longitudinally to compare the general cleanliness and amount of debris $({\times}\;75)$ using SEM. Chi-square test was used $({\alpha}\;=\;0.05)$ to analyze the data. The total time required for removal of filling materials was expressed as mean ${\pm}SD$ (min) and analyzed by the Student t-test $({\alpha}\;=\;0.05)$, Required time for retreatment was $3.25\;{\pm}\;0.32$ minutes for gutta percha/ AH 26 plus sealer and $3.05\;{\pm}\;0.34$ minutes for Resilon. There was no statistically significant difference between the two experimental groups. There was no significant difference between the groups in the cleanliness of the root canal wall. This study showed that Resilon was effectively removed by Gates-Glidden burs and ProFiles.

• Science of Emotion and Sensibility
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• v.19 no.2
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• pp.55-66
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• 2016

This study was aimed to characterize the color of cotton fabric dyed with three different natural resources such as persimmon, citrus, and brown algae and to propose new trend color themes for fashion color planning for newborn and toddler wear. A variety of color shades by dyeing cotton fabric with persimmon, citrus, and brown algae respectively was obtained and each color was also determined if it could be matched with one of Pantone TPX considering authorized color trends for 2016 Spring/Summer. Finally a group of new trend color theme for 2016S/S newborn and toddler wear were proposed for naturally dyed cotton fabric. As results, the three natural dyeing resources gave color gamut with hue ranging from Purple Blue to Green Yellow and with tones including pale, light grayish, soft, grayish, and dull by their single and compound dyeing. A total of 23 colors matched to Pantone TPX were considered for the fashion color planning by natural dyeing. The selected natural colors were grouped as three different color ways and thereafter the color ways were differentiated in terms of representative color sensibility by using subjective evaluation. Finally three characterized color themes were proposed as 'Serenity', 'Juicy', and 'Fancy', each of which has tried to express differentiated feeling of each natural resources for dyeing, to follow up to global color trends, and to contribute to newborn and toddler wear's own requirements and marketability. These results suggest that natural dyeing colors could be applied into fashion color planning in current fashion industries in order to produce more sensible and emotional design of fashion goods using natural dyeing.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.53-60
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• 2009

Purpose: Primary osteoarthritis on the elbow is the result of the growth of osteophytes and contracture of the capsule. It often causes disability on joint motion and pain while exercising. As arthroscopy has developed, the arthroscopic diagnosis and treatment of the elbow have recently become more generalized as well. Therefore, we like to report on arthroscopy for treating elbow arthritis and its results. Materials and Methods: This study includes 23 cases of elbow arthritis that were seen between 2005 June to 2007 June and these patients didn't response to conservative treatment. From this we excluded 18 cases that underwent arthroscopic surgery and among these 18 cases, 6 cases underwent ulnar nerve transfer. The average observation time was 21.3 months and the average age was 48.4 years (range: 22-66 years). The pre and post operative pain was evaluated with using the Visual Analogue Scale (VAS) and functional evaluation was done with using the Mayo elbow Performance Score (MEPS) with the range of joint motion. Results: The VAS score at the last follow up was significantly decreased from 3.4 to 1.9 compare to the preoperative score. The range of joint motion was improved by 25 (0-40) to 8.5 (0-20) in extension and 101.7 (80-140) to 125.2 (85-140) in flexion (p<0.05). The MEPS always showed significant improvement by showing an increase from 65.4 (40-85) to 87.9 (55-100). However, 3 cases showed a decreased range of motion after the operation. One case showed ulnar nerve symptoms after surgery. Conclusion: An arthroscopic procedure can treat the pathologic processes associated with arthritis of the elbow and it was safe and effective in this series.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.150-158
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• 2009

Purpose: With the better understanding of cuff function, partial repair or "force couple repair" for treating massive irreparable rotator cuff tear has gained some popularity. However, there were few reports on the results of partial repair. The purpose of this study was to report the clinical outcome of massive irreparable rotator cuff tears who received arthroscopic force-couple repair or partial repair. Materials and Methods: From June 2005 to Feb 2008, arthroscopic partial repairs were performed for 16 irreparable rotator cuff tears among the 101 large to massive rotator cuff tears that were operated on. Clinical and radiographic evaluation were done at the final follow-up. Results: There were 7 men and 9 women with a mean age of 66.6 years. The mean follow-up period was 27.3 month (range: 15-46). The pain VAS improved from 4.4 ($\pm2.50$) to 2.1 ($\pm2.26$) and the functional VAS improved from 46.9 ($\pm16.64$) to 70.0 ($\pm22.80$). The ASES score improved from 39.0 ($\pm10.80$) to 80.3 ($\pm16.78$) and the KSS score was 81.9 ($\pm16.74$) at the final follow-up. The acromio-humeral distance was 6.6 cm ($\pm1.74$) preoperatively and 6.2 cm ($\pm1.69$) postoperatively without significant change (p=0.3874). The degenerative changes had no statistically progressed (p=0.2663). Conclusion: Partial repair for massive rotator cuff injury patients showed improvement in the clinical score without progression of arthritic change at a mean of 2.3 years follow-up.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.199-206
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• 2009

Purpose: Our goal for this study was to prospectively evaluate the functional & structural outcomes, by means of CT arthroscopy, of arthroscopic double-row fixation for treating rotator cuff tear. We also attempted to determine the variants that affect the functional & structural outcomes. Materials and Methods: Twenty seven consecutive patients underwent arthroscopic rotator cuff repair with double-row fixation. The average age at the time of the operation was fifty six years. The preoperative and postoperative examinations consisted of determining the Constant score, the score for the visual analogue scale for pain, the UCLA score, the American Shoulder and Elbow Surgeons (ASES) score, as well as a full physical examination of the shoulder. Preoperative MR arthrography was used to evaluate the integrity and atrophy of the rotator cuff. We measured the intraoperative tear size in the sagittal and coronal planes. Postoperative CT arthrography was used at one year postoperatively to evaluate the integrity and atrophy of the repaired tendons and muscles. Results: Preoperative MR arthrography revealed an average 29.22 mm tear size in the sagittal plane and an average 22.72 mm tear size in the coronal plane. Twelve cases of supraspinatus muscle atrophy and two cases of infraspinatus atrophy were observed on the preoperative MR arthrography. The average clinical outcome scores all significantly improved at the time of follow-up. At a mean of one year postoperatively, CT arthrography revealed 48.1% of the shoulders had healed, 11.1% showed incomplete healing and 40.7% showed retear of the repaired tendon. Conclusion: Arthroscopic double-row repair can result in improved clinical outcomes and good patient satisfaction. However, the problems about how to enhance healing of the repaired tendon still remain.

• Development and Reproduction
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• v.8 no.2
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• pp.77-84
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• 2004

The purpose of this experiment was to determine the effects of di(2-ethylhexyl) phthalate(DEHP) on reproductive characteristic, blood hematological and chemical values in mice. The male mice were intraperitoneally injected DEHP in negative control(no treatment), positive control(corn oil, 3ml/kg B.W), 0.5, 1.0 and 10.0mg DEHP/kg B.W and the female mice were injected DEHP in control(corn oil, 3ml/kg B.W), 0.5, 1.0 and 10.0mg DEHP/kg B.W with 5 times for 15 days on 3 days interval. The administration of DEHP in male mice were not affect on body weight, epididymis, vesicular gland and coagulating gland weight. The testis weight were slightly higher in DEHP treatment groups than in control. The semen characteristics(sperm concentration, viability, motility and abnormality) of male mice were not difference in all experimental groups. The RBC, Hb, HT, MCV, MCH, MCHC< PLT, albumin, BUN and total protein of blood hematological and chemical values were not affect the administration of DEHP in mice. The WBC values in 10.0mg DEHP group was slightly difference in all experimental group(P>0.05). The histological evaluation of testis, ovary and affevt the reproductive characteristic, blood hematological and chemical values.

• Development and Reproduction
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• v.8 no.2
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• pp.91-97
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• 2004

The objective of this study was to assess that the effects of DEHP administration on reproductive characteristics and blood hematological and chemical values in pups born after DEHP administration in pregnant mice. DEHP was administrated to pregnant mice by intraperitoneally injection with 0, 0.5, 1.0 and 10.0mg/kg B.W, 5 times at 3 days interval from Day 1 to Day 16 in the gestation period. The body weight and reproductive organ weight(testis, epididymis and coagulating gland) in male pups on 45 day after birth was not affected in all experimental groups, but vesicular gland in DEHP groups was significantly lower than that of control group(P<0.05). The semen characteristics of male pups were not affected in DEHP treatment groups. The WBC, HB, HT, MCH and albumin values in male pups were not affected in all experimental groups, but RBC MCV, MCHC, PLT and total protein values were significantly different among the experimental groups(P<0.05). In female pups, the effects of DEHP administration were not affected the body and uterus weight, but the left ovary in 10.0mg DEHP group was significantly heavier than in control and 0.5mg DEHP group(P<0.05). The WBC, MCV, MCH, MCHC, PLT, albumin, BUN and total protein values in female were not different in all experimental groups. The RBC, HB and HT values were significantly different among the experimental gruop(P<0.05). The historical evaluation of testis in male pups that were grown to 45 days after birth was not different in all experimental groups. The ovary in female pups had many corpus luteum in 10.0mg DEHP group. The endometriosisi of uterus was significantly decreased in DEHP group. There results suggest that low concentration of DEHP administration in pup born after DEHP administration in pregnant mice was not affered on reproductive characteristic, but was affected on blood hematological and chemical values.