• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.111-118
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• 2003

I measured the movement range on the hinge articulator and the movement range in an oral. And then I studied to analyze the gap. I got wax records by the movement on the hinge articulator, the movement in an oral and the movement on the hand articulating. I measured the distance of the cusp tips that are close to the mesial direction and the distal direction, the buccal direction and the lingual direction then I compared gaps. As I saw results on data, I knew that the hinge articulator represented the range of mandibular movement restrictively. I could find the decisive contradiction that the sliding movement finished on the hinge articulator although it did not finish in an oral. If the sliding movement does not reappear exactly, it brings a fatal failure to the dental prosthesis. In addition it is impossible that the hinge articulator restores the movement in an oral because the lateral condyle inclination and the horizontal condyle inclination are fixed previously. Therefore dental prosthesisses were made by the hinge articulator, they will interfere with a mastication. I have obtained the following results; 1. The distance of sliding movement on the hinge articulator showed shorter than the distance of sliding movement in oral. This means the increase of cusp inclination of the dental prosthesis that was made on the hinge articulator. Therefore, when the lateral movement occurs in oral, there is a possibility to become the premature as the increase of cusp inclination. 2. The results that were impressed records in oral and impressed records on the hand articulating have many congruities. I think that the simple crown etc. that were made by the hand articulating method except the long span bridge and the free end case that can not measure the vertical dimension exactly can represent similarly the mandibular movement. 3. If we want to represent the mandibular movement similarly, we have to use the articulator that can adjust the horizontal condyle inclination and the lateral condyle inclination at least.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.1
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• pp.34-39
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• 2021

Objectives: The purpose of the study was to assess the occurrence, location, and dimensions of the intraosseous vascular canal in the lateral wall of the maxillary antrum using cone-beam computed tomography (CBCT). Materials and Methods: In this retrospective study, we examined 400 CBCT scans from our archive of patients who had earlier reported to a dental teaching hospital in the United Arab Emirates. The prevalence, location, and dimensions of the lateral antral intraosseous canal (LAIC) in the maxillary antrum were evaluated by 2 examiners using standardised methods. A third examiner was consulted in cases of disagreement. Results: The prevalence of LAIC was 62.3% (249 maxillary antra) among the study population. The mean distance between the most inferior point of the alveolar bone and the inferior border of the LAIC in the posterior maxillary region was 19.83±3.12 mm. There was a significant difference (P=0.05) between the maxillary molar and premolar regions in mean distance from the most inferior point of the alveolar bone and the inferior border of the LAIC. There was no statistically significant difference in mean distance between the most inferior point of the alveolar bone and the inferior border of the LAIC between dentulous and edentulous areas (P=0.1). The G3-intrasinusal type canal less than 1mm in diameter was the most common type of LAIC. Conclusion: This study established the approximate location of the LAIC in a United Arab Emirates cohort, which will assist the oral surgeon in selecting the appropriate site for sinus lift procedures with reduced risk of surgical hemorrhage.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.11
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• pp.2131-2137
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• 2008

In this paper, COP (center of pressure) during quiet standing and squat-and-stand movement was analyzed to compare the postural control of young and elderly subjects with special interest in the elderly females who were reported to have higher fall rate than the elderly males. Subjects include the young subjects (10 males: $21.8{\pm}2.6yrs$, 10 females: $20.4{\pm}0.3yrs$) and the elderly subjects (8 males: $75.5{\pm}4yrs$, 8 females: $72.3{\pm}3.5yrs$). Analysis parameters were the mean of the distance between the instantaneous COP and the average COP (COP distance) and the mean of the COP movement velocity (COP velocity) in both AP (anterio-posterior) and ML (media-lateral) directions. During quiet standing, the COP distance in ML direction of elderly females was significantly greater than that of elderly males and the COP velocity of elderly females in both ML and AP direction were significantly greater than those of all the other groups. During squat and stand movement, the COP distance of elderly females was not significantly different with that of the elderly males. However, the COP velocity of elderly females was significantly greater than that of all the other groups. The large lateral weight shift (COP distance) of elderly females during quiet standing may explain their greater fall rate. However, this does not apply to squat-and stand movement. In contrast, COP velocity results show that the elderly females' COP is rapidly trembling compared to that of elderly males during both quiet standing and squat and-stand movement. This results suggest that rapid trembling or postural sway may reflect the reduced postural control ability and the risk of falling.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.195-205
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• 2013

This study, using the MCC Model to consider consolidation, estimated the range within which no influences occur from lateral movement and its amount of the foundation pile and abutment on the soft ground. This study performed finite element analyses, with variations on the adhesiveness and internal friction angle, depth of soft clay, embankment height, consolidation parameters, and separation distance between the abutment and embankment. The abutment's horizontal displacement exhibits linear change with a longer separation distance, and changes into an exponential form as the embankment gets closer to the abutment. As the soft clay layer becomes 10 m deeper, the horizontal displacement tends to increase 1.5~3.0 times. However, it decreases at a rate of 0.3~0.95 when adhesiveness is increased by 10 $kN/m^2$ and internal friction angle is increased by $5^{\circ}$. The increase change rate in a lateral movement amount becomes greater if it is closer to the abutment when the abutment separation distance is long. When the distance is short, the change rate of horizontal displacement increases in similar a way, but it tends to be decreasing overall.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.1
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• pp.53-61
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• 2005

In this study, we measured Near Point of Convergence(N.P.C) tests, Phoria tests using Von Grafe method and relative convergence tests on 138 men and 162 women, so a total of 300 subjects aged between 8~45 to examine the improvement of the fusion vergence through visual training and obtained as follows. 1. According to the results, the near point of convergence of 57 (19%) subjects were shorter than 7cm, and 243 (81%) were 7cm or longer, having a problem in convergence. After visual training, the number of subjects have the value shorter than 7 cm increased from 57 to 111 (37%), and the number of those have the value 7cm or longer decreased significantly form 243 to 189 (63%). 2. The results of the measure of lateral Phoria at far distance by Von Grafe method showed orthophoria 18 (6%), exophoria 198 (66%), esophoria 84 (28%). After phoria test, we examined the N.R.C and P.R.C test. The results showed that the hope finger was improved after V.T using B.l, B.O card. 3. The results of the measure of lateral Phoria at near distance by Von Grafe method showed orthophoria 6 (2%), exophoria 222 (74%), esophoria 72 (24%). After phoria test, we examine the N.R.C and P.R.C test. The results showed that the hope finger was improved after V.T using B.I, B.O card.

• Journal of the Korean Geotechnical Society
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• v.34 no.12
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• pp.71-82
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• 2018

This study presents a reasonable and economical DCM reinforcement length for the various factors (the embankment height, the distance from the embankment to the underground structure, the depth of the soft ground, and the compression index and the swelling index of the soft ground) that affect the stability of the structure due to lateral movement. Based on these results, we analyzed each factor's degree of influence and figured out which factor influenced the lateral movement most. The cross section of the embankment on the soft ground was modeled by using the Finite Element Program and reinforced with DCM. The results show that the increase rate of the reinforcement length with the increase of the embankment height is about 9~50%, the increase rate of the reinforcement length with the depth of soft ground is about 13~30%, and the increase rate of the reinforcement length with increasing compression index is about 3~25%. In addition, the influence of each factor on each other was analyzed. As a result, among the separation distance, the compressive index and the maximum to minimum slope ratio of the reinforcement length of the embankment height, the separation distance was the largest for the depth of soft ground. As the depth of the soft ground increases, the ratio of the maximum to minimum slope of the reinforcement length according to the embankment height is 3.75, the ratio of the maximum to minimum slope of the reinforcement length according to the spacing distance is 4.3, and the ratio of maximum to minimum slope according to compression index is 2.5. From these results, it is confirmed that the three factors are greatly affected by the depth of soft ground.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.2
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• pp.129-137
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• 2017

The aim of this study was to enhancing the panoramic radiograph's clinical use for assessing mandibular measurements and formulating a function of those measurements from panoramic radiographs and lateral cephalograms in children. The panoramic radiographs and lateral cephalograms of 99 former orthodontic patients with skeletal class III malocclusion were selected. In each radiograph, gonial angles, ramus heights, and distance between lower incisors and symphysis were measured. The values of the studied parameters were compared by paired t-test, Pearson's correlation test and regression analysis. The mean value of the gonial angle in panoramic radiographs was $125.49^{\circ}$, and the value in lateral cephalograms was $127.50^{\circ}$. The Pearson's correlation coefficient (${\rho}$) between mean values of gonial angle in each radiograph was 0.945 (p < 0.001). The relationship between the gonial angle measurements obtained from each radiographs was represented as 'Gonial angle (Lateral cephalograms) = 0.920 ${\times}$ Average gonial angle (Panoramic radiographs) + 12.072' in the linear function. The coefficients of ramus heights, and distance between lower incisors and symphysis portrayed weaker correlations than gonial angles. A panoramic radiograph could be used to determine the gonial angle as accurately as a lateral cephalogram, and each gonial angle showed a strong positive relation. A panoramic radiograph is a useful tool for examining vertical growth pattern of patients, as well as a lateral cephalogram.

• Fire Science and Engineering
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• v.27 no.5
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• pp.75-79
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• 2013

Application of the left lateral tilt position has been recommended during cardiopulmonary resuscitation (CPR) of pregnant patients. However, the left lateral tilt could displace the left ventricle (LV) besides the gravid uterus and may compromise the cardiac pump mechanism of CPR. Thus, we investigated the effect of left lateral tilt on the spatial relationship between the anterior-posterior axis (AP axis), which represents the direction of sternal displacement during CPR, and the LV. We retrospectively reviewed the medical records and multidetector computed tomography (MDCT) scans of 90 patients who underwent virtual gastroscopy using MDCT. Virtual gastroscopy was performed with the patient both in the left lateral tilt position and in the supine position. On an axial image showing the maximal area of the LV, the angle between the AP axis and the LV axis ($Angle_{AP-LV}$), the shortest distance between the AP axis and the mid-point of LV cavity ($D_{AP-MidLV}$) and the shortest distance between the AP axis and the LV apex ($D_{AP-Apex}$) were measured. In the supine scans, the LV was situated on the left side of the AP axis in 87 patients (96.7%). On the left lateral tilt scans, the mean tilt angle was $43.4{\pm}11.0^{\circ}$. $D_{AP-MidLV}$ and $D_{AP-Apex}$ were significantly longer in the left lateral tilt position (p<0.001), but $Angle_{AP-LV}$ was comparable between the positions. This study indicates that the left lateral tilt position may compromise the cardiac pump mechanism of chest compression in pregnant cardiac arrest patients.

• Journal of the Korean Geotechnical Society
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• v.34 no.6
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• pp.5-16
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• 2018

In this study, the large scale laboratory model tests were executed to investigate the lateral resistance characteristics of $2{\times}2$ group pile under lateral loads according to the array method and installation angle of piles. The effect on the behavior of $2{\times}2$ group pile was also investigated through model tests varying the pile diameter and length, distance to pile top from the ground surface, center-to-center (CTC) length and surcharge etc. From these test results, it was found that the lateral resistance of $2{\times}2$ group pile of which piles were constructed slantly in both directions was greater than that of group pile of which piles were constructed vertically. And as a result of parameter tests on the lateral resistance of $2{\times}2$ group pile, it was found that the most important parameter was the pile length. As the embedment depth ratio (L/D) increased to 36.5 from 26.5, the lateral resistance increased 3~4 times or more. But the center-to-center (CTC) length, distance to pile top from the ground surface and surcharge did not affect much on the lateral resistance of group pile.

• Journal of Oral Medicine and Pain
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• v.22 no.1
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• pp.167-181
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• 1997

The aim of this study was to investigate the relationship between velocity and factors which could affect the velocity of mandibular movement. For this study, 30 dental students without any masticatory signs and symptoms and 90 patients with temporomandibular disorders(TMD) were selected as the control group and the patients group, respectively. After determining Angle's classification and lateral guidance pattern of occlusion, clinical examination for TMD was perfomed. Velocity and distance of mandibular movements were recorded with BioEGN, reproducibility index of lateral excursions was evaluated by Pantronic(PRI) and BioEGN (BERI) activity in masticatory and cervical muscles were measured with BioEMG, and occlusal contact time and cross-arch unbalance(Total left-right statistics, TLR) on clenching were recorded with T-scan, respectively. The results of this study were as follows : 1. Velocity in the patients was faster than that in the controls in most mandibular movements, but on wide opening and closing movement, result was reverse. 2. Velocity on closing movements were faster than that on opening movements in the control group and a similar tendency was also shown in the patients group. 3. Patients with muscle disorders showed a tendency to have the highest value of velocity of all diagnostic subgroups, while patients with degenerative joint diseases showed a tendency to have the lowest value. 4. Patients with canine guidance showed a tendency to have the highest value of velocity in three subgroups by lateral guidance pattern, while patients with group function showed a tendency to have the lowest value. 5. BERI had a positive correlation with opening velocity on lateral excursion, while TLR had a negative correlation with opening velocity on swallowing. 6. EMG activity on clenching in masticatory muscles had negative correlation with opening velocity on border movements, and on swollowing, while the activity in rest correlated positively with opening velocity on border movements. 7. There were positive correlation between the velocity and the distance in long components of mandibular trajectory.