• The korean journal of orthodontics
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• v.37 no.5
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• pp.364-375
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• 2007

The purpose of this study was to compare arch dimensions and frequency distribution of arch forms between Korean and Japanese Class I, II, and III malocclusion groups. Methods: The sample consisted of 368 Korean cases (114 Class I, 119 Class II, and 135 Class III malocclusion) and 160 Japanese cases (60 Class I, 50 Class II, and 50 Class III malocclusion). The most facial portion of 13 proximal contact areas was digitized from photocopied images of the mandibular dental arches. Clinical bracket slot points were calculated for each tooth based on mandibular tooth thickness data. Four linear and two proportional measurements were taken. Measurements are statistically analyzed in each malocclusion group. The dental arches were classified into square, ovoid, and tapered forms to determine and compare the frequency distributions between the two ethnic groups. Results: The findings of this study showed that Japanese females in Class I and II groups had a statistically significant narrower mandibular dental arch width compared with the Japanese males, Korean males and Korean females. But in the Class III group, there was no significant difference in the mandibular dental arch size according to the two ethnic groups and genders. Conclusions: The majority of Koreans and Japanese in all the malocclusion groups exhibited square and ovoid arch forms. The most frequent arch forms found in Koreans was square but ovoid for Japanese.

• The korean journal of orthodontics
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• v.34 no.6 s.107
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• pp.481-487
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• 2004

The purpose of this study was to clarify morphologic characteristics between mandibular clinical arch forms in Koreans with normal occlusions. The study included data from 102 Koreans. The most facial portion of 13 proximal contact areas was digitized from photocopied images of the mandibular dental arches. Clinical bracket points were calculated for each tooth based on mandibular tooth thickness data. Four linear and two proportional measurements were taken. The dental arches were classified into ovoid, square and tapered forms. The frequency distributions of the three mandibular arch form classifications were determined and compared between male and female subjects. No significant differences in arch form size were found between the sexes. However, there were a few differences in molar width. It was useful to classify mandibular clinical arch forms present in normal occlusion samples into ovoid, square and tapered categories. The frequency of the ovoid form was the highest, and that of the square form was the second highest. The tapered arch form was found in less than 10 percent of subjects. No significant differences in their frequency distributions and dimensions were shown between males and females.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.3
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• pp.183-205
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• 2021

This systematic review and meta-analysis aimed to analyze the effectiveness of maxillary stabilization splint (SS) therapy to reduce headache (HA) intensity and HA frequency in patients with temporomandibular disorders (TMD)-HA comorbidity. Randomized controlled trials (RCTs) using full-arch coverage, hard resin, and maxillary SS therapy were included. Electronic databases, including Cochrane Library, MEDLINE through PubMed, Web of Science, and EMBASE, were searched. The risk of bias was analyzed based on Cochrane's handbook. The search yielded 247 references up to January 28, 2020. Nine RCTs were included at a high risk of bias. The comparison groups included other splints, counseling, jaw exercises, medications, neurologic treatment, and occlusal equilibration. Four studies reported a statistically significant reduction in HA intensity, and five studies reported significant improvement in HA frequency from baseline at 2-12 months in patients with TMD-HA comorbidity treated with a full-arch hard maxillary SS. HA frequency in tension-type HA (TTH) comorbid with TMD diagnoses of myofascial pain (MFP) or capsulitis/synovitis improved significantly with SS than that with full-arch maxillary non-occluding splint (NOS) in two studies. Comparison groups receiving hard partial-arch maxillary splint nociceptive trigeminal inhibition (NTI) showed statistically significant improvements in HA intensity in patients with mixed TMD phenotypes of MFP and disc displacement comorbid with "general HA." Comparison groups receiving partial-arch maxillary resilient/soft splint (Relax) showed significant improvements in both HA intensity and frequency in patients with HA concomitant with MFP. The meta-analysis showed no statistically significant difference in the improvement of pain intensity at 2-3 months with comparison of the splints (partial-arch soft [Relax], hard [NTI], and full-arch NOS) or splint use compliance at 6-12 months with comparison of the splints (partial-arch Relax and full-arch NOS) versus the SS groups in patients with various TMD-HA comorbidities. In conclusion, although SS therapy showed a statistically significant decrease in HA intensity and HA frequency when reported, the evidence quality was low due to the high bias risk and small sample size. Therefore, further studies are required.

• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.615-628
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• 2000

This report is to study on the progress on which foot arch and planta has been changed according to body type based on 4 tilting of scapular & ilium. This study has been carried out to help contribute to some basic information like these. One was to find out how to assess and analysize the deformity of feet and ankle joint which may have the most impact on ideal alignment of anatomical posture. The other was to figure out how to diagnose and treat the deformity to get to the restoration. The results of this study is as followings; 1. The findings which had been made from 22 persons(50%) having left scapular and ilium forward tilt are as follows. 1) On the longitudinal length of the planta left parts of 18 persons(82%) are longer than the right one. On the transversel length of the planta right parts of 17 persons(77%) are longer than the left one. 2) On the size of medial longitudinal arch the left parts of 20 persons(91%) are more wider than the right one. 3) On the sign of supinated foot, the left parts of 18 persons(82%) are more common than the right one. 4) On the thickness of big toe, the left parts of 14 persons(64%) are thicker than the right one. 2. The findings which had been made from 15 persons(34%) having right scapular and ilium forward tilt are as follows. 1) On the longitudinal length of the planta right parts of 11 persons(73%) are longer than the left one. On the transversel length of the planta left parts of 13 persons(87%) are longer than the right one. 2) On the size of medial longitudinal arch the right parts of 13 persons(87%) are more wider than the left one. 3) On the sign of supinated foot, the right parts of 12 persons(80%) are more common than the left one. 4) On the thickness of big toe, the right parts of 7 persons(47%) are thicker than the left one. 3. The findings which had been made from 3 persons(7%) having left scapular and right ilium forward tilt are as follows. 1) On the longitudinal length of the planta right parts of 2 persons(67%) are longer than the left one. On the transversel length of the planta left parts of 2 persons(67%) are longer than the right one. 2) On the size of medial longitudinal arch the right parts of 3 persons(100%) are more wider than the left one. 3) On the sign of supinated foot, the right parts of 2 persons(67%) are more common than the left one. 4) On the thickness of big toe, the left parts of 2 persons(67%) are thicker than the right one. 4. The findings which had been made from 4 persons(9%) having right scapular and left ilium forward tilt are as follows. 1) On the longitudinal length of the planta left parts of 3 persons(75%) are longer than the right one. On the transversel length of the planta right parts of 2 persons(50%) are longer than the left one. 2) On the size of medial longitudinal arch the left parts of 3 persons(75%) are more wider than the right one. 3) On the sign of supinated foot, the left parts of 3 persons(75%) are more common than the right one. 4) On the thickness of big toe, the left parts of 3 persons(75%) are thicker than the right one.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.3
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• pp.397-406
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• 2002

The purpose of this study was to clarify the palatal arch length, width and volume in the primary and permanent dentition. Samples were consisted of normal occlusion in the primary dentition(50 males and 50 females) and permanent dentition(43 males and 43 females). Their upper plaster casts were used and through 3-dimensional laser scanning(3D Scanner, DS4060, LDI, U.S.A.), cloud data, polygonization, section curve, loft surface and fit and horizontal plane were made for measuring the palatal arch length, width and volume(Surfacer 10.0, Imageware, U.S.A.). Correlation coefficients were calculated separately for males and females in each group(SPSS 10.0). The results were as follows : 1. Average distance from the fit plane to the points(tooth-tooth-palate) was greater in the permanent dentition than those of primary dentition. 2. Palatal volume was greater more than 3 times in the permanent dentition, especially it was greater in male compared to female with significance(p<0.05). 3. Palatal width of male was greater in the primary and permanent dentition but palatal length, only in the permanent dentition than that of female(P<0.05). 4. Correlation coefficients were statistically most significant between the palatal volume and size of posterior palatal width and total palatal length(r=0.401, r=0.450, r=0.678, r=0.654).

• The Research Journal of the Costume Culture
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• v.24 no.3
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• pp.315-323
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• 2016

The present study is intended to study sole types necessary for shoe designs for elementary school students that are in age groups in growth periods, and 3D midsole design utilizing 3D printing technology. This study analyzed data from the 3D measurement of the feet of 1,227 elementary school students aged 7-13 years residing in the capital region conducted as part of the 6th Anthropometry of Size Korea. In addition, 3D midsoles by sole type were designed utilizing a Rhino CAD, and midsole prototypes were output utilizing a Zortrax-M200 3D Printer. Through a cluster analysis of sole shapes by type, sole shapes were classified into three types. Type 1 has small values of foot lengths and foot breadths, with large toe 1 angles and high arch heights. Type 2 has intermediate values of foot lengths and foot breadths, with small toe 1 angles and high arch heights. Type 3 has large values of foot lengths and foot breadths with small toe 1 angles and low arch heights. On reviewing the results of design of 3D midsoles by sole type, it can be seen that the midsoles were designed according to characteristics by sole type. The results of the sole type analysis in the present study are expected to be meaningful as basic data for the development of shoe insoles for elementary school students.

• The korean journal of orthodontics
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• v.13 no.1
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• pp.73-82
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• 1983

The author studied on the dental arch widths and lengths and height of palates at 3 groups of dentition: mixed dentition, early permanent dentition, young adult, having normal occlusion and dentition. The models of the 336 maxillary and mandibular case, made from alginate-base hydrocolloid impressions were measured and analyzed statistically. The result as follows; 1. The upper intercanine width increased between the mixed dentition group and early permanent dentition group but there was no change in the young adult group in both sexes. The lower intercanine width increased between the mixed dentition group and early permanent dention group in the male. 2. The upper and lower 1st bimolar width increased slightly with age in the male but there was no change in the female. 3, The sex difference found in this study was one of absolute size, the female being slightly smaller than the male in the early permanent dentition group and young adult. 4. The arch length had no notable sexual differences and decreased between the mixed dentition group and early permanent dentition group. There was no change in the arch length in the young adult. 5. The height of palate increased gradually with age.

• Tunnel and Underground Space
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• v.14 no.1
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• pp.26-34
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• 2004

The effectiveness of UAM is generally accepted, but there has not been much rigorous study on UAM and its mechanical support mechanism is yet to be established. Also, most of UAM installations depend on empirical judgement rather than on engineering knowledge. In this study, an attempt to confirm the support effects and to understand the support mechanism of UAM has been made by analyzing the mechanical behavior of umbrella pipes installed in various ground conditions. The effects of overburden thickness, pipe size, overlap length and the placement of steel arch are studied using a three-dimensional finite element method. From the numerical parametric study, the support mechanism of UAM has been confirmed by analyzing the structural forces in the umbrella pipes due to the excavation.

• Journal of Korean Association for Spatial Structures
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• v.16 no.2
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• pp.39-45
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• 2016

Membrane structure is a system that is stabilized by maintaining a tensile state of the membrane material that originally cannot resist the bending or pressure. Also, it is a system that allows the whole membrane structure to bear external loads caused by wind or precipitation such as snow, rain and etc. Tension relaxation phenomenon can transpire to the tension that is introduced to the fabric over time, due to the innate characteristics of the membrane material. Thus, it is important to accurately understand the size of the membrane tension after the completion of the structures, for maintenance and management purposes. The authors have proposed the principle of theoretically and indirectly measuring the tension by vibrating the membrane surface with sound waves exposures against the surface, which is compartmentalized by a rectangular boundary, and by measuring the natural frequency of the membrane surface that selectively resonates. The authors of this paper measured the tension of preexisting membrane structure for its maintenance by using the developed portable measurement equipment. Through analyzing the measurement data, the authors review the points that should be improved and the technical method for the new maintenance system of membrane tension.

• Geomechanics and Engineering
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• v.35 no.2
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• pp.149-163
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• 2023

This paper presents stability evaluation of unlined tunnels with semi-circular arch and straight sides (SASS) driven in non-homogeneous and anisotropic undrained clay. Numerical analysis has been conducted based on lower bound finite element limit analysis with second order cone programming under plane strain condition. The solutions will be used for the assessment of stability of unlined semi-circular arch tunnels and tunnels in which semi-circular roof is supported over rectangular/square sections. The stability charts have been generated in terms of a non-dimensional factor considering linear variation in undrained anisotropic strength for normally consolidated and lightly over consolidated clay with depth, and constant undrained anisotropic strength for heavily over-consolidated clay across the depth. The effect of normalized surcharge pressure on ground surface, non-homogeneity and anisotropy of clay, tunnel cover to width ratio and height to width ratio of tunnel on the stability factor and associated zone of shear failure at yielding have been examined and discussed. The geometry of tunnel in terms of shape and size, and non-homogeneity and anisotropy in undrained strength of clay has been observed to influence significantly the stability of unlined SASS tunnels.