• Journal of the korean academy of Pediatric Dentistry
• /
• v.21 no.2
• /
• pp.429-438
• /
• 1994

Since the introduction of pit and fissure sealants in the early 1970's, many studies have been published amply documenting the efficacy of these materials as caries-preventive agents. However, the acceptance of the technique by dentist has been questionable. This survey was investigated the attitudes toward and use of pit and fissure sealants by dentist in Chonbuk area. The results were as follows: 1. Utilization of pit and fissure sealants is very high. Only 15% of dentists never use pit and fissure sealants, whereas 85% generally use pit and fissure sealants. 2. Most dentists reported that their knowledge of pit and fissure sealants was gained through dental schools education. 3. Concern about difficult to sell' to patient, poor retention of pit and fissure sealants and unsubstantiated by research were given as the main reasons why pit and fissure sealants was not used. 4. Patient demands and various educate program were given as important factors that would lead to increase use of pit and fissure sealants.

• Earthquakes and Structures
• /
• v.24 no.1
• /
• pp.53-64
• /
• 2023

Earth fissures with several kilometers will inevitably approach or cross the metro line, significantly threatening the safety of the underground structure in the earth fissure site. However, the influence of the earth fissure site's amplification effect on the metro station's dynamic response is still unclear. A representative earth fissure in Xi'an was taken as an example to establish a numerical model of a metro station in the earth fissure site. The dynamic response characteristics of the metro stations at different distances from the earth fissure under various seismic waves were calculated. The results show that the existence of the earth fissure significantly amplifies the dynamic response of the nearby underground structures. The responses of the axial force, shear force, bending moment, normal stress, horizontal displacement, inter-story drift, and relative slip of the metro station were all amplified within a specific influence range. The amplification effect increases with the seismic wave intensity. The amplification effect caused by the earth fissure has relatively weak impacts on the axial shear, shear force, bending movement, normal stress, and horizontal movement; slightly larger impacts on the inter-story drift and acceleration; and a significant impact on the relative slip. The influence ranges of the axial force and normal stress are approximately 20 m. The influence ranges of the acceleration and inter-story drift can reach 30 m. Therefore, the seismic fortification level of the underground structure in the earth fissure site needs to be improved.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.33 no.2
• /
• pp.336-347
• /
• 2006

Pit and fissure sealants has been proven as safe and effective method of caries prevention. But improper application of pit and fissure sealant may masking the caries process in occlusal fissure. Dentists have to understand the correct and exact application method of pit and fissure sealant for he good result of caries prevention. A key factor to enhanced the effectiveness of caries prevention is retention of pit and fissure sealant. Deep penetration of material into fissure and least marginal leakage around the fissure orifice are the major concerns for dentists to achieve the successive application of pit and fissure sealants. This paper reviewed the literature on the pit and fissure sealants under the following subtitles for enhanced retention : (1) application timing, (2) Indication, (3) Occlusal prophylaxis, (4) Materials, (5) Penetration, (5) Recall check Dental profession must perform the exact application of pit and fissure sealant because this procedure is one of the most technique-sensitive one in dental field.

• Journal of Korean Clinical Health Science
• /
• v.2 no.1
• /
• pp.17-23
• /
• 2014

Purpose. This study was to investigate the relationship between the palpebral fissure size and the exophthalmos in a population of Korean adult women subjects with normal eye status. Methods. From November 2012 to September 2013, The authors analyzed the morphological values in 73 Korean adults population. The test was performed using the Hertel exophthalmometer and verner califer. Analysis of subjects data were recorded using the spss version 20.0 a statistical program (IBM Co, Armonk, NY USA). Results. The average age of the 73 subjects (146 eyes) was (21.219+/-0.261)mm. the average value of palpebral fissure was (25.110+/-1.646)mm in width and (8.096+/-1.464)mm in height. The average value of exophthalmos was (15.002+/-1.922)mm. There was a significant relationship(P>0.05) in the average size between the width and height in palpebral fissure. Also, there was a significant relationship(P>0.05) in the average size between the palpebral fissure width and exophthalmos. On the other hand, there was a significant relationship(P>0.01) in the average size of palpebral fissure height and exophthalmos. Conclusions: In this study, these results suggested that the palpebral fissure and exophthalmos had a significant relationship in the average value of size in Korean adult women population.

• Journal of Korean Clinical Health Science
• /
• v.3 no.3
• /
• pp.427-434
• /
• 2015

Purpose: This study was to investigate the relationship between the palpebral fissure and the exophthalmos in an elder women population in Korea subjects with normal eye status. Methods. From November 2014 to July 2015, The author analyzed the morphological values in 81 Korean elder women population. The clinical test was performed using the Hertel exophthalometer and verner califer. Analysis of data were described using the spss 20 and Pearson's test. Results. The mean age of the 81 subjects (162 eyes) was (73.938+/8.585)mm. The mean value of palpebral fissure was (5.673+/-2.065)mm in width and (24.179+/-4.409)mm in height. The mean value of exophthalmos was (5.537+/-2.151)mm. There were a significant relationship(P>0.01) in the mean size between the width and height in palpebral fissure. Also, there were a significant relationship(P>0.01) in the mean size between the palpebral fissure width and exophthalmos. Also, there were a significant relationship(P>0.01) in the mean size between the palpebral height width and exophthalmos. However, there were not significant relationship(P>0.01) in the mean size between the palpebral fissure width and exophthalmos in right eye. On the other hand, The relationship between right eye and left eye of the palpebral fissure and exophthalmos was similar results. Conclusions. In this study, these results suggested that the palpebral fissure and exophthalmos was a significant relationship in the mean value of morphologic characters in Korean elder women population.

• Archives of Craniofacial Surgery
• /
• v.18 no.2
• /
• pp.89-91
• /
• 2017

Background: The superior orbital fissure is a small area that connects the middle cranial fossa and the orbit. Many studies have measured the size of the superior orbital fissure. However, there is no standard value for the size of the superior orbital fissure. Therefore, we conducted this study to provide the average size of the superior orbital fissure in Korean adults. Methods: We measured the widths of the superior orbital fissures of 142 patients using computed tomography scans. Because the width of the superior orbital fissure varies at different locations, we measured the superior orbital fissure width at the level of the optic canal. Results: In the males, the width of the superior orbital fissure on both sides was $3.79{\pm}0.93mm$, and these values were $3.79{\pm}0.96mm$ for the left side and $3.783{\pm}0.92mm$ for the right side. In the females, the widths of the superior orbital fissures were $3.62{\pm}1.35mm$ on the left side, $3.69{\pm}1.18mm$ on the right side, and $3.65{\pm}1.26mm$ across both sides. Conclusion: There were no significant differences between the males and females or between the left and right sides. The present study suggests that we may accept the hypothesis that a congenitally narrow superior orbital fissure may be a risk factor for the superior orbital fissure syndrome. Surgeons should take precaution with patients who have narrow superior orbital fissures during the perioperative period.

• Journal of Korean Ophthalmic Optics Society
• /
• v.4 no.2
• /
• pp.119-122
• /
• 1999

The palpebral fissure height of 67 healthy koreans were examined. Measurements were obtained with high resolution digital image processing, with the eyes in primary gaze, in 45-degree right gaze, and in 45-degree left gaze. When a criterion of equal to or greater than 1mm was used, the prevalence of physiologic palpebral fissure asymmetry was 13.1 (8/61) in primary gaze, 24.6%(15/61) in right gaze, and 16.4%(10/61) in left gaze. The largest observed palpebral fissure asymmetry was 1.795mm. After correcting for any existing fissure asymmetry in primary gaze, two-tailed trivariate analysis of variance showed that most corrected palpebral fissure asymmetries are less than 1mm and adducting eye tended to be wider in horizontal gaze. Also this effect of wider fissure in the adducting eye was the same for right gaze or left gaze, and found no significant effect of gender on palpebral fissure asymmetry. The mean increase in the palpebral fissure of the adducting eye was 0.29mm for right gaze and 0.21mm for left gaze.

• Earthquakes and Structures
• /
• v.18 no.4
• /
• pp.423-435
• /
• 2020

An accurate evaluation of structural damage is essential to performance-based seismic design for the structure across the earth fissure. By comparing the calculation results from three commonly used damage models and the experimental results, a weighted combination method using Chen model was selected in this paper as the seismic damage evaluation. A numerical model considering the soil-structure interaction (SSI) was proposed using ABAQUS software. The model was calibrated by comparing with the experimental results. The results from the analysis indicated that, for the structure across the earth fissure, the existence of earth fissure changed the damage distribution of the structural members. The damage of structural members in the hanging wall was greater than that in the foot wall. Besides, the earth fissure enlarged the damage degree of the structural members at the same location and changed the position of the weak story. Moreover, the damage degree of the structure across the earth fissure was greater than that of the structure without the earth fissure under the same excitation. It is expected that the results from this research would enhance the understanding of the performance-based seismic design for the structure across the earth fissure.

• Geomechanics and Engineering
• /
• v.24 no.6
• /
• pp.573-588
• /
• 2021

The interaction of cracks and water significantly affects the fracture mechanism of rocks. In this study, laboratory tests were conducted using sandstone samples containing a single fissure to explore the hydro-mechanical behaviors in the failure process of pre-cracked rocks. The internal crack characteristics were also analyzed using X-ray CT scanning. The results show that the confining pressure has the greatest effect on the mechanical properties (e.g., strengths, elastic modulus, and Poisson's ratio), followed by the fissure inclination and water pressure. At a lower fissure inclination, the confining pressure may control the type main cracks that form, and an increase in the water pressure increases the number of anti-wing cracks and the length of wing cracks and branch cracks. However, the fracture behaviors of samples with a higher fissure inclination are only slightly affected by the confining pressures and water pressures. The effect of fissure inclination on the internal crack area is reduced with the propagation from the fissure tips to the sample ends. The fissure inclination mainly affects the value of permeability but not affect the trend. The impact of pre-existing fissure on permeability is smaller than that of confining pressure and water pressure.

• Archives of Plastic Surgery
• /
• v.38 no.6
• /
• pp.879-882
• /
• 2011

Purpose: Superior orbital fissure syndrome is a rare neurological complex. Superior orbital fissure syndrome may result from a variety of inflammatory, infectious, neoplastic, iatrogenic, traumatic, vascular cause. The author report a patient who suffered from superior orbital fissure syndrome after inferior orbital wall reduction. Methods: A 26-year-old female suffered from inferior orbital wall fracture with inferior gaze limitation and orbital soft tissue herniation. On posttrauma 10 day, inferior orbital wall was reduced using endoscope and porous polyethylene ($Medpor^{(R)}$) was inserted. On immediate postoperation, she reported that extraocular movement was limited in almost any directions. She underwent exploration surgery to release the presence of extraocular muscle impingement. But, there was no observation of extraocular muscle impingement. On postoperative one day, high-dose steroid therapy was started to release superior orbital fissure syndrome which was defined in postoperative computed tomography. Results: After one month of high-dose steroid therapy, extraocular movement limitations improved progressively in all directions. In four months, extraocular movement recovered completely. Conclusion: Superior orbital fissure syndrome may occur after surgical procedure of orbital wall reduction. Prompt diagnosis and treatment with mega-dose corticosteroid is an effective option for avoiding disaster from compressive syndrome.