• The Korean Journal of Vision Science
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• v.20 no.4
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• pp.589-596
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• 2018

Purpose : We compared intraocular pressure (IOP) values measured by two types of tonometers in condition of normotensive and glaucomatous rat model. We tried to determine which of tonometer can more easily and accurately measure the IOP of animal model. Methods : Glaucomatous eyes were induced by intracameral injections of hyaluronic acid in right eyes of six-week-old male Spargue-Dawley (SD) rats. Normotensive contralateral eyes were left eyes of the SD rats. IOP was measured using a rebound tonometer (Tonolab) and a immersive tonometer ($Tonopen^{(R)}$ XL) about 3:00 pm. Results : The mean IOP values of normotensive control eyes were $10.80{\pm}1.03mmHg$ by Tonopen, and $15.10{\pm}0.73mmHg$ by Tonolab. They were statistically insignificant (p = .1). The mean IOP values of glaucomatous experimental eyes were $30.20{\pm}2.67mmHg$ by Tonopen, and $37.90{\pm}2.73mmHg$ by Tonolab. They were statistically insignificant (p = .95). High IOP values of glaucomatous eyes by two types of tonometers had strong positive correlation each other (r = .904, p < .01). Conclusion : This is the first study to compare IOP values using two types of tonometers between normotensive and glaucomatous model made by intracameral injection of hyaluronic acid. Tonopen should be used carefully when the IOP is within normal range, and both Tonopen and Tonolab can be used reliably when the IOP is high.

• Journal of Korean Society of Neurocognitive Rehabilitation
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• v.10 no.2
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• pp.19-26
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• 2018

Many people do not realize that they have poor neck posture. Incorrect forward head posture can lead to turtle neck. This aim to development of specific chair to reduce tension and other symptoms of turtle neck posture. This turtle neck syndrome adjusting chair is a chair that supports the hip and shin of a person to help them correct their posture. It is consisted of the shin support that supports the shin in an angle and the hip support that supports one's hip while the shin is supported at an angle, the main frame that has the two of them connected and the fluid seat that is joined at the top of the hip support and reacts accordingly to the shape of the hip. This is a posture correction chair which has the fluid seat that provides unstable hip support so that it can allow a person to realize their posture from the constant stimulation about the posture. When one seats on the posture correction chair, their hip and shin are supported at an angle that straitens their back, and as their back is straightened, their shoulders and chest are opened, and the neck is positioned at the middle to help them correct their posture. An unbalanced posture causes discomfort to the person seated at the chair, and the person sitting on the posture correction chair will continuously adjust his/her posture to balance the hips to keep the correct posture. Through this process, the person shall adjust his/her left and right posture, ultimately increasing the effectiveness of posture correction. A future collective study on the continuous posture correction of people having turtle neck syndrome using this posture correction chair is required.

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.407-413
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• 2022

This study demonstrates a method for synthesis of amine functionalized and easily size controllable silica nanoparticles through biomimetic polyamine complex. First, we generate a polyamine nanocomplex composed of polyallylamine hydrochloride (PAH) and phosphate ion (pi) to synthesize silica nanoparticles. The size of polyamine nanocomplex is reversibly adjusted within the range of about 50 to 300 nm according to the pH conditions. Amine groups of the PAH in the nanocomplex catalyzes the condensation reaction of silicic acid. As a results, silica nanoparticles are synthesized based on nanocomplex in a very short time. Finally, we synthesize silica nanoparticles with various sizes according to the pH conditions. In the process of synthesizing silica nanoparticles, polyamine chains that act as catalysts are incorporated into the inside and surface of the particles, subsequently, amine groups are exposed on the surface of silica nanoparticles. As a results, the synthesis and surface modification of silica nanoparticles are performed simultaneously, and the silica nanoparticles introduced with amine groups can be easily synthesized by adjusting the sizes of the silica nanoparticles. Finally, we demonstrate the synthesis of functional silica nanoparticles in a short time under milder conditions than the conventional synthetic method. Furthermore, this method can be applicable to bioengineering and materials fields.

• Applied Microscopy
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• v.39 no.4
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• pp.333-340
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• 2009

In the present study, ultrastructural features of the mesophyll tissue have been investigated in Crassulacean acid metabolism (CAM)-performing succulent Orostachys. A large central vacuole and numerous small vacuoles in the peripheral cytoplasm were characterized at the subcellular level in both developing and mature mesophyll cells. The most notable feature was the invagination of vacuolar membranes into the secondary vacuoles or multivesicular bodies. In many cases, tens of single, membrane-bound secondary vacuoles of various sizes were found to be formed within the central vacuole. multivesicular bodies containing numerous small vesicles were also distributed in the cytoplasm but were better developed within the central vacuole. Occasionally, electron-dense prevacuolar compartments, directly attached to structures appearing to be small vacuoles, were also detected in the cytoplasm. One or more huge central vacuoles were frequently observed in cells undergoing differentiation and maturation. Consistent with the known occurrence of morphologically distinct vacuoles within different tissues, two types of vacuoles, one representing lytic vacuoles and the other, most likely protein storage vacuoles, were noted frequently within Orostachys mesophyll. The two types coexisted in mature vegetative cells but did not merge during the study. Nevertheless, the coexistence of two distinct vacuole types in maturing cells implies the presence of more than one mechanism for vacuolar solute sorting in these species. The vacuolar membrane is known to be unique among the intracellular compartments for having different channels and/or pumps to maintain its function. In CAM plants, the vacuole is a very important organelle that regulates malic acid diurnal fluctuation to a large extent. The membrane invagination seen in Orostachys mesophyll likely plays a significant role in survival under the physiological drought conditions in which these Orostachys occur; by increasing to such a large vacuolar volume, the mesophyll cells are able to retain enormous amounts of acid when needed. Furthermore, the mesophyll cells are able to attain their large sizes with less energy expenditure in order to regulate the large degree of diurnal fluctuation of organic acid that occurs within the vacuoles of Orostachys.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.642-651
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• 2008

This study was carried out to give basic information of traumatic injuries of primary and permanent teeth which can be used for diagnosis and management of injured teeth. From January 2003 to July 2007, 570 children with 1394 teeth who came to pediatric dentistry and emergency center of Chonnam National University Hospital due to the traumatized teeth participated in this study. The following data were investigated. : age, sex, causes and places of trauma, position of injured teeth, types of injury, and treatment at the first visit. 1. Trauma prevailed at the age of 1, $6{\sim}8$, $17{\sim}18$ and the rate of males was more likely to be higher than the rate of females(1.9 : 1). 2. The main cause of injury is a fall-down injury for primary and mixed dentition, but is a traffic accident and fighting for permanent dentition, respectably. The place of injury for primary dentition is mainly home(45.3%), while street for mixed and permanent dentition. 3. The position of injured teeth according to the area in the mouth is mainly maxillary anterior teeth in both case of primary and permanent teeth and especially, the ratio of central incisors is high. 4. The periodontal tissue injury occurred the most frequently in the primary and the permanent teeth, but the ratio of hard tissue injury in the permanent teeth increased, compared with the primary teeth. 5. Among treatments at the first visit, observation without actual treatment comprised 75.6% in the primary teeth and 55.4% in the permanent teeth, respectably. The pulp necrosis occurred in 20.3% of the primary teeth and 26.6% of the permanent teeth in the case of the periodontal tissue injuries, respectably.

• The korean journal of orthodontics
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• v.25 no.3 s.50
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• pp.299-310
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• 1995

The purpose of this study is to know about the positional change of second molar when orthodontic treatment is performed. To know about it, we andlysed cephalogram pre. and post treatment for 54 adult patients who werefinished orthodontic treatment by banding to the first molar and classify them into 4 groups Class I extraction group 15, Class I nonextraction group 12, Class II group 13, class Class III group 14. The following conclusions were obtained : 1. In the extraction group of Class I , mandibular second molar showed less extrusion and mon distal inclination than first moarl. But maxillary second molar showed more or less extrusive and mesial inclination to much the same degree of first molar. 2. Inthe non-extractio group of Class I, mandibular second molar in intrusive to first molar, it showed smilar distal inclination to first molar. But maxillary second molar is extrusive similarly to first molar. 3. In the group of Class II , mandibular second molar is less extrusive than first molar and maxillary second molar is more extrusive than first molar. 4. In the group of Class III, mandibular second molar showed similar extrusion to first molar and more distal inclination than first molar. But maxillary second molar showed less extrusion than first molar. 5. A comparision of the positional change of second molar among groups : The change of distance from FH plane to funcation point of maxillary second molar is the difference between Class I extraction group and Class II group, Class I extraction group and Class III group. The change of maxillary second molar to palatal plane and occlusal plane is the difference between Class I extraction group and Class III group. And the change of distance from mandibular plan to furcation point of mandibular second molar is difference between Class I extraction group and non-extraction group, Class I non-extraction group and Class II group, Class I non-extraction group and Class III group. But the change of angle of mandibular second molar to mandibular plane and occlusal plane is make no difference in among groups.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.1
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• pp.175-180
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• 2008

Traumatic injuries to the primary dentition are commonly encountered problems in dental practice. It is found that 30% of the children had injuries to the primary dentition and 22% to the permanent dentition. The greatest incidence of trauma to the primary dentition occurs at the ages of 2 and 3 as children start to learn motor coordination. Because teeth and alveolar bone are traumatized simultaneously, alveolar bone fractures are likely to occur when multiple teeth are involved in injuries. Dental splints are indicated for the management of maxillofacial fractures. They enable anatomic reduction of fractured segments and help immobilization and maintenance of the fragments after reduction. They also act as a stabilizer during rehabilitation. Various types of dental splints are available. In this case, routine resin-wire splint technique could not be applied because of the child's uncooperative behavior. Oral sedation was not indicated because N.P.O. had not been preceded. Therefore, we decided to use open-cap acrylic splint instead. Stabilization using open cap acrylic splint requires minimum chair time with reduced discomfort to both patient and dentist. It is an effective means of splint for uncooperative children and especially useful when other means of fixation have been failed. Because trauma on the primary dentition can affect the underlying permanent tooth germ, it is important to monitor eruption process of the permanent dentition.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.24 no.1
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• pp.4-12
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• 2015

Purpose: Due to the presence of various muscles around lips, variety of facial expression can be made and changes from aging process such as wrinkles can develop on the facial skin by the action of multiple muscles. In animals, skin and muscles are developed in the entire body. On contrast, they are well developed only in the face and just one is present in the neck and the palm. Alar band was defined as outer wrinkle formed by zygomaticus minor muscle, which is common in Koreans. This study aimed to investigate clinical prevalence of alar band. Materials & Methods: Subjects were chosen from 780 new patients who visited private clinic in Gyeonggi province for orthodontic treatment. Presence of alar band was examined from the smile extraoral photos. Correlation among skeletal form, lip protrusion, gender, and age were evaluated. Results: Prevalence of alar band was higher in women (27.9%) than in men (18.5%) with statistical significance (p<0.05). With respect to age, prevalence of alar band was 19.4% in age 0-9 y, 16.9% in age 10-19 y, 31.2% in age 20-29 y, 39.5% in age 30-39, 56.5% in age 40-49. Prevalence was gradually increased from patients in their 20s to patients in their 40s and statistical significance was found (p<0.001). Concerning SN_NP, prevalence was 26.2% in normodivergent facial type, 22.0% in hyperdivergent facial type, and 32.2% in hypodivergent facial type. Hypodivergent facial group had higher prevalence but statistical significance was not observed. Statistically significant difference was not found regarding upper lip. However, prevalence of the alar band was 26% in patients with normal lower lip, 14.7% in patients with pretruded lower lip, and 33.3% in retruded lower lip. The prevalence was higher in patients with retruded lower lip with statistical significance (p<0.05). Conclusions: 27.8% on previous anatomical study and this study showed 27.8% prevalence of alar band in clinical smile photographs. Clinical photograph study showed that alar band was more prominent in women, older people, and people with retruded lips with statistical significance. This will provide valuable diagnostic information for esthetic consideration.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.3
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• pp.488-495
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• 2001

Treatment of class II malocclusions require distalization of maxillary molars into class I relationship. Intraarch distal molar movement techniques have recently assumed an important role in young patients. In this study, the dental and skeletal effects of the pendulum appliance were evaluated by means of cephalometric radiographs. The samples were consisted of 19 patients: 11 females and 8 males, mean age $11.68{\pm}1.52$ years. Measurements were obtained from cephalometric prior to and the day of removal of the pendulum appliance. Treatment changes were analyzed. The following results were obtain. 1. The pendulum appliance produced $2.94{\pm}1.54mm$ distal molar movement with a mean intrusion of $1.17{\pm}0.97mm$, mean period $18.13{\pm}7.95$ weeks. 2. The anchor tooth was $1.34{\pm}1.40mm$ forward movement and $0.48{\pm}0.99mm$ extrusion, and labial tilting of incisors. 3. The angle between palatal plane and mandibular plane increased significantly. 4. There was no significant difference in according to 2nd molar position. 5. Total movement was consisted of 74% distal movement of 1st molar and 26% forward movement of the anchor tooth.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.3
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• pp.345-354
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• 2001

The purpose of this study was to make public oral health plan more effective and the improvement of the hospital management system for better clinical dental practice. Distribution and trends were examined in all patients who had been examined and diagnosed at Department of Pedodontics, Dental Hospital, Chosun University over 10 year-period from 1990 to 1999 Results were as follows, 1. The number of patients per year was increasing trend after 1996 and higher visiting rate in male(55.9%) than in female(44.1%). 2. Age distribution had shown $3\sim4$ year-old cup being the largest (23.4%) and each percentage of $5\sim6,\;7\sim8,\;0\sim2,\;9\sim10,\;11\sim12,\;13\sim14,\;above\sim15$ year-old group was 19.9%, 17.7%, 14.6%, 12.6%, 8.0%, 3.3%. 0.5%. 3. Geographic distribution showed a majority of patients in Kwang-Ju (83.0%). Group in the suburbs of Kwang-Ju(Jang-Sung group) was 5.4%. 4. Dental caries showed the highest percentage(40.5%) in chief complaints and percentage of oral exam, orthodontic problem, oral pain, trauma, supernumerary teeth, swelling was 13.9% 12.6%, 8.8%, 7.4%, 5.5%, 4.9%. 5. In all patients with traumatic problem, crown fracture showed the highest percentage(41.4%) and percentage of subluxation was 19.4%. 6. Majority(78.7%) of patients were not refered, and percentage of patients refered from local clinic was 20.5%. 7. Patients who had periodic check-up comprised 19.6%, and percentage of after 3, 6, 9, 12, 18, 24month was 36.7%, 22.2%, 13.5%, 11.3%, 5.4%, 11.0%.