• Tuberculosis and Respiratory Diseases
• /
• v.45 no.2
• /
• pp.457-464
• /
• 1998

This report describes a 5-month follow-up of the efficacy of Herbst oral appliance(OA) in a obstructive sleep apnea syndrome patient who has failed with uvulopalatopharyngoplasty(UPPP) and was unable to tolerate to subsequent nasal continuous positive airway pressure(CPAP) because of mouth air leak. The obstructive sleep apnea and daytime performance were markedly improved by regular home use of OA, and the patient still continues to use OA without complications. It is suggested that OA can be a successful alternative therapeutic modality in patients who are unable to tolerate to nasal CP AP, especially after UPPP.

• International Journal of Aeronautical and Space Sciences
• /
• v.13 no.3
• /
• pp.386-397
• /
• 2012

The stability and structure of bluff-body stabilized hydrogen flames were investigated numerically and experimentally. The velocity of coflowing air was varied from subsonic velocity to a supersonic velocity of Mach 1.8. OH PLIF images and Schlieren images were used for analysis. Flame regimes were used to classify the characteristic flame modes according to the variation of the fuel-air velocity ratio, into jet-like flame, central-jet-dominated flame, and recirculation zone flame. Stability curves were drawn to find the blowout regimes and to show the improvement in flame stability with increasing lip thickness of the fuel tube, which acts as a bluff-body. These curves collapse to a single line when the blowout curves are normalized by the size of the bluff-body. The variation of flame length with the increase in air flow rate was also investigated. In the subsonic coflow condition, the flame length decreased significantly, but in the supersonic coflow condition, the flame length increased slowly and finally reached a near-constant value. This phenomenon is attributed to the air-entrainment of subsonic flow and the compressibility effect of supersonic flow. The closed-tip recirculation zone flames in supersonic coflow had a reacting core in the partially premixed zone, where the fuel jet lost its momentum due to the high-pressure zone and followed the recirculation zone; this behavior resulted in the long characteristic time for the fuel-air mixing.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.17 no.2
• /
• pp.107-112
• /
• 2001

The prosthodontic treatment of severely resorbed edentulous patients has been one of the frustrating areas due to extensive loss of tissues. The integrated neuromuscular balance among tongue, lip, and cheek is compromised. The retention, stability, and support are the three major factors to influence the clinical outcome. Fish described a denture as having three surface, with each surface playing an independent and important role in the over all fit, stability, and comfort of the denture. He recommended that the polished surface should be a series of inclines so that pressure from muscular activity will retain dentures. Within the denture space there is an area that has been termed the neutral zone. The neutral zone is that area in the mouth where, during function, the forces of the tongue pressing outward are neutralized by the forces of the cheeks and lips pressing inward. According to Jacobson and Krol, neuromuscular control interacts to provide retention and the relationship of polished surface of denture base to the surrounding muscular structure of orofacial capsule facilitates the stability and retention. This neutral zone concept has been demonstrated with various modification by a number of authors. The theory used to develop the denture base contours is based on the belief that the muscle should functionally mold not only the border but the entire polished surface. Lott and Walsh reported the clinical success on complete mandibular dentures with application of neutral zone concept. A number of studies demonstrated that denture stability and retention are more dependent on correct position of the teeth and correct contour of external surfaces of the denture in a severely resorbed alveolar ridge. This article presents a prosthodontic approach to treatment of a edentulous patient using neutral zone technique to improve the retention and stability of the prosthesis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.28 no.5
• /
• pp.383-389
• /
• 2002

This is a retrospective study on emergency patients with active oral bleeding. The study was based on a series of 135 patients treated as emergency patients at Wonju Christian Hospital, from Jan. 1, 1997, to Dec. 31, 2001. The postoperative bleeding was the most frequent cause of active oral bleeding in emergency room and bleeding from trauma and medically compromised (bleeding disorders) patients were next in order of frequency. In the injury of maxillofacial vessels, peak incidence was occurred in the inferior alveolar vessel (42.9%), followed by the submucosal vessel of lip & cheek, the superior alveolar vessel, and sublingual vessels. The most common disease of bleeding disorders was vascular wall alteration (infection, etc), followed by liver disease, thrombocytopenic purpura, anti-coagulation drugs in order. In the characteristics of dental diseases on bleeding disorders, periodontal disease and alveolar osteitis (osteomyelitis) were more common. The hemostasis was most obtained by use of wound suture, simple pressure dressing, drainage for infection control and primary interdental wiring of fracture. In the complication group, the infrequent incidence was showed in vomiting, hypovolemic shock, syncope, recurred bleeding & aspiration pneumonia. In the uncontrolled oral bleeding, the injured vessels were suspected as skull base & ethmoidal vessels. In this study, authors found that the close cooperation between the dentistry (Oral and maxillofacial surgery) and the medicine (emergency & internal medicine) was the most important for early proper control of active oral bleeding. And then post-operative wound closure, drainage for infection control and previous systemic evaluation of bleeding disorders were critical for the prevention of postoperative bleeding in the local dental clinic.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.21 no.2
• /
• pp.129-137
• /
• 2021

Background: Inappropriate use of intravenous and inhaled anesthetics may be dangerous in infants undergoing facial cleft surgeries. This study primarily aimed to compare the effect of infraorbital nerve block on sevoflurane requirement in infants undergoing cheiloplasty. Intraoperative opioid consumption, hemodynamics, blood glucose levels, extubation time, and delirium were also compared. Methods: This prospective, randomized, double-blinded study was conducted in 34 infants undergoing cheiloplasty under general anesthesia. After induction, group A received bilateral infraorbital nerve block with 0.5 mL of 0.5% bupivacaine and group B 0.5 mL saline. An increase in heart rate or blood pressure > 20% was managed by increasing sevoflurane by 2-2.5%, followed by fentanyl 0.5 ㎍/kg bolus. The chi-square test and independent-sample t-test were used where applicable. Results: Demographics, duration of surgery, and intravenous fluids used were comparable between the groups. Compared to group A, patients in group B had significantly higher consumption of fentanyl (14.2 ± 4.4 ㎍ vs. 22.1 ± 6.2 ㎍) and sevoflurane (14.2 ± 4.8 mL vs. 26.8 ± 15.6 mL). Intraoperative hemodynamic parameters were significantly lower in group A, the number of times increases in hemodynamic parameters occurred, and fentanyl supplemental bolus was required remained significantly lower in group A than in group B. Intraoperative glycemic levels remained higher in group B, and the extubation time was significantly shorter in group A than in group B (4.40 ± 1.60 min vs. 9.2 ± 2.18 min). Group A had a lesser occurrence of postoperative delirium. Conclusion: Supplemental infraorbital block in infants undergoing cheiloplasty under general anesthesia resulted in significantly decreased anesthetic requirements and optimal hemodynamic and glycemic levels with faster extubation and lesser delirium.

• The Korean Journal of Pharmacology
• /
• v.23 no.2
• /
• pp.77-85
• /
• 1987

This study was carried out to determine the role of cholinoceptors in the ventrolateral medulla on central control of blood pressure (BP) and heart rate (HR). In rats anesthetized with urethane and paralyzed, microinjections of the neuroexcitatory amino acid L-glutamate (300 ng/site) were performed to functionally identity the vasopressor area (VLPA) and the vasodepressor area (VLDA) in the ventrolateral medulla oblongata. 1. The bilateral microinjection of carbachol (300 ng/site) into the VLPA produced significantly an increase in BP and HR which was not blocked by bilateral pretreatment of hexamethoium ($4\;{\mu}g/site$). 2. The bilateral microinjection of physostigmine (200 ng/site) and oxotremorine (300 ng/site) into the VLPA produced significantly an increase in BP respectively. 3. The bilateral microinjection of atropine ($4\;{\mu}g/site$) into the VLPA produced significantly a decrease in BP and HR. 4. The bilateral micro injection of acetylcholine (500 ng/site) and dimethylphenylpiperazinium (500 ng/site) into the VLDA produced significantly a decrease in BP and HR respectively. 5. The depressor and bradycardiac responses elicited by the bilateral microinjection of acetylcholine (500 ng/site) into the VLDA were blocked by bilateral pretreatment of hexamethonium ($4\;{\mu}g/site$). The results suggest that the activation of cholinoceptors in VLPA produce hypertensive and tachycardiac responses which may be mediated by muscarinic receptors, and the activation of cholinoceptors in VLDA produce hypotensive and bradycardiac responses which may be mediated by nicotinic receptors.

• Journal of Digital Convergence
• /
• v.19 no.2
• /
• pp.315-322
• /
• 2021

The purpose of this study was to examine the correlations of oral myofunction and oral environment for the elderly with systemic diseases and to suggest need to improve oral health for the elderly. Data were collected from 64 elderly over the age of 65, from April to June 2019. Data were surveyed on general characteristics, oral myofunction, oral health-related quality of life, oral bacteria. Analysis was performed using PASW Statistics ver 18.0. The subjects were 43.8% systemic diseases, among them 40.6 percent of the people with more than two. The number of functional teeth was 18.6. Age was negatively correlated with functional teeth(r=-.384, p<.01) and tongue pressure (r=-).104, p<.001). Tongue pressure was a positive correlation with lip force(r=.279, p<.05). Age and total number of bacteria was negative correlation(r=-.336, p<.01). The functional teeth and total number of bacteria was positive correlation(r=.551, p<.001). The number of systemic diseases and total number of bacteria was positive correlation(r=.327, p<.01) the analysis of oral myofunction and oral bacteria in older patients with systemic diseases It was meaningful in suggesting a plan to improve oral health for the elderly. A practical policy plan was required to improve the quality of oral health life in a super-aged society.

• Tuberculosis and Respiratory Diseases
• /
• v.43 no.4
• /
• pp.558-570
• /
• 1996

Background : The detection of Collapsible airways has important therapeutic implications in chronic airway disease and bronchial asthma. The distinction of a purely collapsible airways disease from that of asthma is important because the treatment of the dormer may include the use of pursed lip breathing or nasal positive pressure ventilation whereas in the latter, pharmacologic approaches are used. One form of irreversible airflow limitation is collapsible airways, which has been shown to be a Component of asthma or to emphysema, it can be assessed by the volume difference between what exits the lung as determined by a spirometer and the volume compressed as measured by the plethysmography. Method : To investigate whether volume difference between slow and forced vital Capacity(SVC-FVC) by spirometry may be used as a surrogate index of airway collapse, we examined pulmonary function parameters before and after bronchodilator agent inhalation by spirometry and body plethysmography in 20 cases of patients with evidence of airflow limitation(chronic obstructive pulmonary disease 12 cases, stable bronchial asthma 7 cases, combined chronic obstructive pulmonary disease with asthma 1 case) and 20 cases of normal subjects without evidence of airflow limitation referred to the Pusan National University Hospital pulmonary function laboratory from January 1995 to July 1995 prospectively. Results : 1) Average and standard deviation of age, height, weight of patients with airflow limitation was $58.3{\pm}7.24$(yr), $166{\pm}8.0$(cm), $59.0{\pm}9.9$(kg) and those of normal subjects was $56.3{\pm}12.47$(yr), $165.9{\pm}6.9$(cm), $64.4{\pm}10.4$(kg), respectively. The differences of physical characteristics of both group were not significant statistically and male to female ratio was 14:6 in both groups. 2) The difference between slow vital capacity and forced vital capacity was $395{\pm}317ml$ in patients group and $154{\pm}176ml$ in normal group and there was statistically significance between two groups(p<0.05). Sensitivity and specificity were most higher when the cut-off value was 208ml. 3) After bronchodilator inhalation, reversible airway obstructions were shown in 16 cases of patients group, 7 cases of control group(p<0.05) by spirometry or body plethysmography d the differences of slow vital capacity and forced vital capacity in bronchodilator response group and nonresponse group were $300.4{\pm}306ml$, $144.7{\pm}180ml$ and this difference was statistically significant. 4) The difference between slow vital capacity and forced vital capacity before bronchodilator inhalation was correlated with airway resistance before bronchodilator(r=0.307 p=0.05), and the difference between slow vital capacity and forced vital capacity after bronchodilator was correlated with difference between slow vital capacity and forced vital capacity(r=0.559 p=0.0002), thoracic gas volume(r=0.488 p=0.002) before bronchodilator and airway resistance(r=0.583 p=0.0001), thoracic gas volume(r=0.375 p=0.0170) after bronchodilator, respectively. 5) The difference between slow vital capacity and forced vital capacity in smokers and nonsmokers was $257.5{\pm}303ml$, $277.5{\pm}276ml$, respectively and this difference did not reach statistical significance(p>0.05). Conclusion : The difference between slow vital capacity and forced vital capacity by spirometry may be useful for the detection of collapsible airway and may help decision making of therapeutic plans.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.13 no.1
• /
• pp.2206-2217
• /
• 1971

Spillway and discharge channel of reservoirs require the Control of Large volume of water under high pressure. The energies at the downstream end of spillway or discharge channel are tremendous. Therefore, Some means of expending the energy of the high-velocity flow is required to prevent scour of the riverbed, minimize erosion, and prevent undermining structures or dam it self. This may be accomplished by Constructing an energy dissipator at the downstream end of spillway or discharge channel disigned to dissipated the excessive energy and establish safe flow Condition in the outlet channel. There are many types of energy dissipators, stilling basins are the most familar energy dissipator. In the stilling basin, most energies are dissipated by hydraulic jump. stilling basins have some length to cover hydraulic jump length. So stilling basins require much concrete works and high construction cost. Flip bucket type energy dissipators require less construction cost. If the streambed is composed of firm rock and it is certain that the scour will not progress upstream to the extent that the safety of the structure might be endangered, flip backet type energy dissipators are the most recommendable one. Following items are tested and studied with bucket radius, $R=7h_2$,(medium of $4h_2{\geqq}R{\geqq}10h_2$). 1. Allowable upstream channel slop of bucket. 2. Adequate bucket lip angle for good performance of flip bucket. Also followings are reviwed. 1. Scour by jet flow. 2. Negative pressure distribution and air movement below nappe flow. From the test and study, following results were obtained. 1. Upstream channel slope of bucket (S=H/L) should be 0.25<H/L<0.75 for good performance of flip bucket. 2. Adequated lip angle $30^{\circ}{\sim}40^{\circ}$ are more reliable than $20^{\circ}{\sim}30^{\circ}$ for the safety of structures.

• Journal of Bio-Environment Control
• /
• v.27 no.2
• /
• pp.158-165
• /
• 2018

The effects of different kinds of supplementary lighting or heating lamps on the yield, cut flower life, and leaf color of cut rose were compared and analyzed. For this purpose, light emitting diode lamp (LED), metal halide lamps (MH), and high-pressure sodium lamps (HPS) as the supplementary lamps, and carbon fiber infrared lamp (NCFI) were installed on hydroponic cultivation bed in a cut rose farm. The yield of cut flower rose and the number of marketable flowers were greatly increased in spring and autumn by HPS treatment, but not in winter. The length of flower stalk was longer than that of control in the spring but decreased in winter. It seemed likely that the shorter flower stalk in winter was due to the shortened period of vegetative growth compared to the control because flowering was promoted by supplementary lighting. Vase life was not different among treatments in the autumn when the lighting time was short, but in winter, it was prolonged to 3 more days by only HPS, compared with the control. Leaf color was significantly affected by light treatment in winter rather than autumn. Leaf color was darkened in all supplementary lamps (LED, MH, HPS) treatment, whereas NCFI was similar to the control in leaf color. In conclusion, HPS is considered to be a very good supplementary lamp because it increases the length of flower stalk and the yield and prolongs vase life in cut roses. Even though NCFI could function as a heating lamp radiating a lot of heat, it was considered that the role as a supplementary light is unsatisfactory because the number of marketable flowers decreases and the quality index of cut rose deteriorates by NCFI.