• The Journal of the Korean dental association
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• v.58 no.4
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• pp.194-205
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• 2020

Objective: The purpose of this study was to evaluate the accuracy of the inter-arch relationship of digital models generated using two types of intraoral scanners. Methods: In total, 34 plaster model samples were used. Two corresponding digital models were created using two types of intraoral scanners. A total of 15 variables were measured. The plaster model was directly measured using a digital caliper, while the digital models were measured using a software. The accuracy of the measurements was evaluated using repeated measures analysis of variance and the Friedman test. Results: Among the 15 measurements, 6 measurements[Overjet, Overbite, DZ_11-41 (Distance between the gingival zenith of maxillary right central incisor and mandibular right central incisor), DZ_16-46 (Distance between the gingival zenith of maxillary right first molar and mandibular right first molar), DZ_13-33 (Distance between the gingival zenith of maxillary right canine and mandibular left canine), and DZ_23-43 (Distance between the gingival zenith of maxillary left canine and mandibular right canine)]showed statistically significant differences, with DZ_23-43 showing the largest difference of 0.18 mm. The other measurements showed no statistically significant differences. Conclusions: Regardless of the type of scanner used for preparation, digital models can be used as clinically acceptable alternatives to conventional plaster models.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.1
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• pp.95-122
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• 1990

This study was done to analyze the occlusal curve as one of the factors to be considered for maintenance of occlusal stability in the orthodontic and prosthodontic treatments. Sixty gnathological casts we.e obtained from 43 subjects with normal occlusion and 17 subjects with some of temporomandibular disorders. The occlusal surfaces of gnathologic casts were duplicated by using a Color kit SK-700 and tile reference points of X, Y coordinates were digitized by using the Summagraphic digitizer and 18AT computer system. The Z coordinates of cusp height were measured by 0.01mm measurable caliper. The mathematical computer program of least square method was used to analyze the occlusal curve arranged by three dimensional coordinates of X, Y, Z. The following results were obtained : 1. The occlusal curve of buccal and lingual cusp tips was fitted to the ellipse, and the occlusal curve of anterior teeth was fitted to a part of the circle in the analysis of conic sections. 2. The radius of Spee's curve showed individual differences, but was average 98.7mm in male subjects and 93.7mm in female subjects. 3. The radius fo Spee's curve according to the half of canine width showed the least coefficient of variation. 4. The radius of Spee's curve was not significantly relative to the lateral occlusal contacts on laterotrusion and the absence or presence of temporomandibular disorders. 5. The radius of Wilson's curve showed individual difference and the size of radius was followed by the order of 1st premolar, 2nd premolar, 2nd molar and 1st molar.

• Journal of Korean Foot and Ankle Society
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• v.18 no.1
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• pp.14-18
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• 2014

Purpose: The purpose of this report is to evaluate the measured values of normal Korean calcaneus by conduct of a cadaveric study. Materials and Methods: A total of 42 calcanei were obtained from Korean cadavers. A digital goniometer was used for measurement of B$\ddot{o}$hler's angle, Gissane angle, posterior facet articular inclination angle, and Fowler-Philip angle of calcaneus. A vernier caliper was used for measurement of the maximal antero-posterior length, maximal transverse width, and maximal height of calcaneus. Results: The average B$\ddot{o}$hler's angle, Gissane angle, posterior facet articular inclination angle, and Fowler-Philip angle was $32.3^{\circ}{\pm}5.0^{\circ}$, $114.4^{\circ}{\pm}8.2^{\circ}$, $61.2^{\circ}{\pm}4.4^{\circ}$, and $60.3^{\circ}{\pm}7.6^{\circ}$. The average maximal antero-posterior length, maximal transverse width, and maximal height of calcaneus was $74.2{\pm}3.0mm$, $43.0{\pm}4.0mm$, and $42.5{\pm}3.0mm$. Conclusion: The measured values of normal Korean calcaneus were lower than the values reported in the international literature. Therefore, development of appropriate instruments reflecting the anatomical characteristics of Koreans will be needed.

• Korean Journal of Community Nutrition
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• v.5 no.3
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• pp.502-512
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• 2000

A survey was conducted on 222 students in two elementary schools in rural areas, one was a rural small city and the other was in the countryside. By measuring their skin-foldness in 4 spots by caliper, the body fatness of 5 grades(BFGr) of the subjects was resulted as follows ; 28.0% of boys and 6.7% of girls were classified as obese the and 34.1% of boys and 31.1% of girls as overweight. Comparing by region, children in the small city seemed to be fatter than the ones in the countryside(21.7% vs. 17.2% as obesity). Comparing by gender, boys were fatter than girls(28.0% vs. 6.7% as obesity). When recategorizing body fatness from 5 grades(BFGr) into 3 groups(BFGp) as overweight group(obesity+overweight), normal and underweight group(underweight+severe-underweight), we observed no significant difference in childrens dietary habits and food intake frequencies by BFGp. Overweight and underweight groups enjoyed snacking before dinner more frequently than the normal group(42.1-59.3% vs. 31.5%). The subjects showed poor nutrition knowledge score with relatively high attitude score about weight control and dietary behavior score was a little lower than the attitude score. Nutrition education programs, like camps, should stress on childrens nutrition knowledge. BFGp related to obesity attitude positive, a very low level and the latter related to diet, exercise and fasting attitudes at positive levels. Therefore overweight children seemed to be motivated easily. Also the higher the in exercise-value score, the more increased was shown in exercise attitude at positive, very low level. Emphasizing exercise-value in camp programs might make childrens exercise attitude more positive. As strategies for a rural obesity camp program are being developed by obese and non-obese children. The camp would be held over summer vacation for 3 days(2 nights) at the participants expence not exceeding 50,000 won. Contents of the program cover nutrition knowledge, and exercise-value as well as cooking lessons, exercise practice, and self-esteem enhencement.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.4
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• pp.755-779
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• 1996

This study was designed to development of stock tray for Korean. The subjects for this study were 374 persons(male : 204, female : 170) with age $19{\sim}28$. The study models were made with irreversible hydrocolloid impression material and conventional stock tray, Individual trays were made on the study model and the master models were made after impression with polysulfide rubber impression material. Each of the master models measured 12 measuring points on the maxillary model and 13 measuring points on the mandibular model with digital sliding caliper. The values were analyzed statistically by SAS analysis. The measuring points were analysed and were consulted for the development of new stock tray for Korean. Maxillary models were divided into four groups acceding to the width between buccal alveolar ridges below the contact point of first molar and second molar. The size of new tray of the upper first group was 82mm (width), 60mm(length). That of the upper second group was 77mm (width), 59mm (length). That of the upper third group was 72mm (width), 58mm (length). And that of the upper fourth group was 67mm (width), 57mm (length). Mandibular models were devided into three group according to the width between lingual alveolar ridges below the second molar. The size of new tray on lower first group was 40mm (width), 55mm (length). That of the lower second group was 36mm (width), 55mm (length). And that of the third group was 32mm (width), 55mm (length). The author tested the fitness of newly designed stock tray in 52 subjects with normal occlusion and obtained good results that the problems of conventional stock tray were worked out.

• YAKHAK HOEJI
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• v.55 no.1
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• pp.39-44
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• 2011

Many reports indicate that $18{\beta}$-glycyrrhetinic acid ($18{\beta}$-GA) from Glycyrrhizae Radix has anti-inflammatory and immunoregulatory activities, whereas reports regarding anticancer activity of the compound are few. In present study, we investigated antitumor effect of $18{\beta}$-GA on tumor caused by A549 cancer cell in mice. Data resulting from the cytotoxicity assay showed that $18{\beta}$-GA caused killing of A549 cells. $LD_{50}$ values of $18{\beta}$-GA were app. 180 ${\mu}M$ and 80 ${\mu}M$, corresponding to 48 hr- and 72 hr-treatments, displaying that the killing activity was more effective as the $18{\beta}$-GA treatment was prolonged. Based on these data, antitumor effect of $18{\beta}$-GA was tested in nude mice. For induction of the tumor, A549 ($3{\times}10^6$ cells/mouse) was injected subcutaneously into the lateral abdomen of nude mice (Balb/c nu/nu). To determine the antitumor effect, nude mice with tumor were given $18{\beta}$-GA (1 mg/200 ${\mu}l$/mouse) intraperitoneally every three days for four times. Tumor-sizes were measured with a caliper for a period of 24 days. Results showed that the $18{\beta}$-GA treatment reduced the tumor-sizes (P<0.05) as compared with negative control nude mice that received diluent (DPBS). The reduction degree was greater than reduction degree by doxorubicin (60 ${\mu}g$/mouse), and the pattern of reduction was almost sustained during the entire period of the observation. In conclusion, our studies demonstrate that $18{\beta}$-GA has antitumor activity to the A549 cancer cell-caused tumor.

• The Journal of Korean Medicine
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• v.31 no.3
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• pp.8-16
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• 2010

Objective: This study aimed to investigate the antitumor effects of water extracts of Panax notoginseng (WEPN) in NCI-H460 human lung cancer cell xenografted nude mice. Materials and Methods: We cultured NCI-H460 cell lines and xenografted them to nude mice. The mice were divided into 3 groups; positive control group, NCI-H460+150 mg/kg WEPN-treated group, and NCI-H460+300 mg/kg WEPN-treated group. They had been raised and treated in 28 days. We checked their body weight and tumor weight and volumes twice a week and their absolute organ weight and microhistological observation at the final day. We also calculated their tumor inhibition rate (I.R.), mean survival time and percent increase in life span (% ILS). Results: Body weight of WEPN (300 mg/kg) treated mice tended to slightly greater increase than those of the positive control group, but had no significance. Tumor volume (measurement with a caliper) of WEPN-treated mice tended to be lower than that of the positive control group. Inhibition rate (I.R.) of the WEPN group decreased more than the positive control group, but had no significance. Results of tumor weights and volume (plethysmography) had no significance. Mean survival time and percent increase in life span (% ILS) in the WEPN 300 mg/kg treatment group were higher than those of any other group (p<0.05). In absolute organ weights, the WEPN (150-300 mg/kg) treatment group decreased liver weights (p<0.05). Liver tissue of mice treated with WEPN (300 mg/kg) did not show any specific lesions. Conclusion: We suggest that WEPN may have potential as a growth inhibitor of solid tumors induced by NCI-H460 without any side effects. However, this study has limitations in proving anti-tumor effects of WEPN, so further studies to overcome those limitations will be needed.

• The korean journal of orthodontics
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• v.15 no.1
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• pp.67-74
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• 1985

The primary objective of this study is to make the prediction percentile tabulation of the sun of mesiodistal width of the unerupted permanent canines and premolars derived from the sum of mesiodistal width of the erupted permanent mandibular incisors in Korean population. The subjects were 316 individuals with normal occlusion aged 11 to 23 years. The sum of mesiodistal width of mandibular incisors, and the sum of mesiodistal width of maxillary canine, first and second premolars, and the sum of mandibular canine, first and second premolars were measured from the dental cast models using the sliding caliper (Mitutoyo Co.). From the study, the results are as follows: 1. The sum of M-D width of mandibular incisors and the sum of M-D width of maxillary canines, first and second premolars, and the sum of M-D width of mandibular canine, first and second premolars were smaller than those of American Caucasians and Negros. 2. The correlation coefficient between the sum of M-D width of mandibular incisors and that of maxillary or mandibular canines, first and second premolars was found to be 0.598 and 0.586, respectively. 3. The regression constants were determined to evaluate the sum of M-D width of the unerupted permanent canines and premolars derived from the sum of M-D width of the erupted permanent incisors. 4. The prediction percentile tabulation were made in an attempt to predict the total M-D width of the unerupted permanent canines and premolars derived from the total M-D width of the erupted permanent mandibular incisors.

• Imaging Science in Dentistry
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• v.42 no.4
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• pp.243-247
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• 2012

Purpose: This study was performed to compare the inverted digital images and film-based images of dry pig mandibles to measure the periodontal bone defect depth. Materials and Methods: Forty 2-wall bone defects were made in the proximal region of the premolar in the dry pig mandibles. The digital and conventional radiographs were taken using a Schick sensor and Kodak F-speed intraoral film. Image manipulation (inversion) was performed using Adobe Photoshop 7.0 software. Four trained examiners made all of the radiographic measurements in millimeters a total of three times from the cementoenamel junction to the most apical extension of the bone loss with both types of images: inverted digital and film. The measurements were also made in dry mandibles using a periodontal probe and digital caliper. The Student's t-test was used to compare the depth measurements obtained from the two types of images and direct visual measurement in the dry mandibles. A significance level of 0.05 for a 95% confidence interval was used for each comparison. Results: There was a significant difference between depth measurements in the inverted digital images and direct visual measurements (p>|t|=0.0039), with means of 6.29 mm ($IC_{95%}$:6.04-6.54) and 6.79 mm ($IC_{95%}$:6.45-7.11), respectively. There was a non-significant difference between the film-based radiographs and direct visual measurements (p>|t|=0.4950), with means of 6.64mm($IC_{95%}$:6.40-6.89) and 6.79mm($IC_{95%}$:6.45-7.11), respectively. Conclusion: The periodontal bone defect measurements in the inverted digital images were inferior to film-based radiographs, underestimating the amount of bone loss.

• Journal of Korean Academy of Nursing
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• v.40 no.6
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• pp.844-851
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• 2010

Purpose: This study was conducted to assess optimal needle length for gluteal intramuscular injections (IM) via simple skinfold thickness (SFT). Methods: For this study, 190 healthy adults were recruited and grouped into eight groups according to gender and body mass index (BMI) (kg/$m^2$). The Korean Society for the Study of Obesity criteria defines a BMI under 20 as underweight, 20.1-22.9 as normal, 23-24.9 as overweight and over 25 as obese. For each participant, the SFT of dorsoguteal (DG) and ventrogluteal (VG) sites were measured using a caliper. Subcutaneous tissue thickness was acquired through ultrasonic images. Results: For men in the overweight and obese groups at the DG site, for the obese group at the VG site, and for women in the normal weight, overweight and obese groups at both sites, the mean subcutaneous tissue thickness exceeded 1.84 cm, the minimal length for a 1 inch needle used for IM. At the DG site, optimal intramuscular needle length (OINL) was 1.4 times in women and 1.0 times in men compared to SFT. At the VG site, OINL was 1.3 times in women and 0.9 times in men compared to SFT. Conclusion: The results of this study suggest that SFT is a reliable index to determine optimal needle length with minimal effort prior to IM.