• Title/Summary/Keyword: Plastic damage

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AN EXPERIMENTAL STUDY ON THE EFFECT OF LASER ON SOFT TISSUE HEALING (백서에서 레이저 조사가 연조직 치유에 미치는 영향에 관한 연구)

  • Park, Young-Wook;Jang, Jae-Hyun;Kim, Jung-Hwan;Park, Jung-Min;Lee, Suk-Keun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.31 no.3
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    • pp.222-228
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    • 2009
  • Objectives: This study is aimed to compare the wound healing processes between conventional scapel wound and Er,Cr:YSGG (Erbium,Chromium, Yttrium, Scandium, Gallium, Garnet) laser wound using experimental animals. Experimental Design: Two types of wounds were made by linear and round incisions using scalpel and Er,Cr:YSGG laser, respectively, on the thigh of Sprague-Dawley rats. Sprague-Dawley rats were serially sacrified as follows: post operative 12, 24, 48 hours, and 3, 7, 14 days. The skin wounds were grossly and microscopically analyzed during the healing period. Result: The Er,Cr:YSGG laser incision showed better wound healing for the linear incision experiment than the scapel incision. Whereas the scapel incision showed better wound healing for the round incision experiment than the Er,Cr:YSGG linear incision. As the Er,Cr:YSGG laser damage in the round incision experiment could be much increased compared with the round incision by scapel. So, the round incisions by the Er,Cr:YSGG laser were resulted in the poor wound healing compared with those by the scapel. Conclusion: The Er,Cr:YSGG laser is more favorable for the fast linear incision, while the scapel is more favorable for the modified round incision.

Marketing of cleaned fresh ginseng and pre-packaging fumigation of 2-phenylethyl alcohol on ginseng storability (세척인삼 유통 현황과 포장전 2-phenylethyl Alcohol 훈증이 저장성에 미치는 영향)

  • Kim, Sun-Ik;Sung, Bong-Jae;Kim, Hyeon-Ho;Hwang, Yong-Soo
    • Korean Journal of Agricultural Science
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    • v.38 no.2
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    • pp.205-212
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    • 2011
  • The potential factors for quality loss of cleaned fresh ginseng and technology to be associated with the improvement of marketability through pre-packaging fumigation were examined. Major microorganisms isolated from fresh ginseng included Botrytis cinerea, and Erwinia sp. Others such as Cylindrocarpon sp., Fusarium spp., Pennicilium spp., Bacillus spp. were also found at relatively low frequency. The bacterial density of vacuum packaged fresh ginseng rapidly increased during simulated marketing. Little correlation between bacterial growth and package swelling was found. In order to improve packaging method of fresh ginseng, pre-packaging treatment of 2-phenylethyl alcohol (PE, 100 uL/L, 4 hr) was examined. The fumigation treatment effectively inhibited the growth of bacteria density and also effective on keeping firmness of ginseng root, especially in cortical portion. The internal gas compositions of plastic container packaged for ginseng were approximately ranged between 6 to 8% $O_2$and 3 to 4% $CO_2$. The $O_2$ level of fumigation treatment was lower than control whereas $CO_2$ level was higher. The upsurge of ethylene evolution I day after simulated marketing was found only in fumigation treatment but it returned to ordinary level at day 2. The sucrose content of 2-PE treatment was significantly reduced at 5 days after simulated marketing but reducing sugars like glucose and fructose remained at higher level. The difference in sugar levels was reduced after 10 days of simulated marketing. The decay of fresh ginseng began at the lateral or fine root, which is weak to physical damage, in general. The epidermis was more damaged. Plastic container packaging with PE fumigation could be an alternative to vacuum packaging, which allows an aerobic environment and prevents anaerobic respiration. Further study of pre-package fumigation is required to improve technology of fresh ginseng marketing.

A Study on the Lateral Flow in Soft Soils subjected to Unsymmetrical Surcharges (편재하중을 받는 연약지반의 측방유동에 관한 연구)

  • 안종필
    • The Journal of Engineering Geology
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    • v.3 no.2
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    • pp.177-190
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    • 1993
  • When soft soils are effected by unsymmetrical surcharge due to embankement and abutements of a bridge, large plastic sheraring deformations such as settlements, lateral displacements, upheavals and sliding shearing failure in the soils occurred and they have often damaged considerabily to the soils and structure. This study examines the existing theoretical background for the behavior of the displacement of soils by unsymmetrical surcharge on the soft soils and compares the analytical results to the actual measurements performed through the model test. The procedures of model test are that a model stock device is made and soft soils are filled in a container which fixes the soils. Then the displacements observed when surcharge load increa ses by regular interval at undrainage condition. It analyzes the relation of soil characteristics to displacement, critical surcharge and ultimate bearing capadty, condition of plastic flow and lateral flow pressure, comparing them with the existing theories. Understanding the causes of lateral displacement in soft soils due to unsymmetrical surchages will prevent a damage in advance.

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PRELIMINARY STUDY OF NEUROSENSORY RECOVERY AFTER BSSRO (악교정 수술 후 발생하는 신경회복에 대한 연구 I)

  • Lee, Dong- Keun;Jo, I-Su;Min, Seung-Ki;Oh, Seung-Hwan;Jeong, Chang-Ju;Lee, Eun-Tak
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.23 no.2
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    • pp.144-154
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    • 2001
  • Dysfunction of the inferior alveolar nerve indicated by various degree of numbness of the lower lip and chin is one of the few drawbacks of mandibular osteotomy, especially Bilateral Sagittal Split Ramus Osteotomy(BSSRO) and genioplasty. Although it has been recorded throughout the history of this techniques, it is true etiology poorly understood. In this study, 22 consecutive patients under class III malocclusiion impression and undergoing orthognathic surgery(BSSRO only 11 case, BSSRO with genioplasty 11 case) were studied using 4 neurosensory test(static light touch, directional discrimination, two-point discrimination, pin pressure nociception) with post OP 1 week, 2 weeks, 4 weeks, 8 weeks, 12 weeks, 24 weeks, On control group, 10 members without trauma and nerve damage history, nerve test was accomplished. We concluded majority of patients return of sensation during post operative 24 weeks. Althought immediate nerve deficit are 92.2%, 97.2% 88.9% these are recovered to 25%, 35.72%, 10.71% at 24 weeks. Nerve recovery rate increased prominently between post 4 weeks and 8 weeks. There is no statistically difference about neurosensory deficit among the chin area. Neurosensory deficit more severe when the BSSRO with genioplasty group than the only BSSRO group. Immediate neurosensory deficit is larger left side than right side but after 6 months, there is no significantly difference between left side and right side. Static light touch and pin pressure nociception are more sensitive method of neurosensory deficit than two point discrimination.

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Effectiveness of Computed Tomography for Blow-out Fracture

  • Rhee, Seung-Hyun;Kim, Tae-Seup;Song, Jae-Min;Shin, Sang-Hoon;Lee, Jae-Yeol
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.36 no.6
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    • pp.273-279
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    • 2014
  • Purpose: This study assessed the association between eye symptoms (enophthalmos or diplopia) and site of damage, volume, deviated inferior rectus muscle (IRM) and type of fracture with computed tomography (CT). The intent is to anticipate the prognosis of orbital trauma at initial diagnosis. Methods: Forty-five patients were diagnosed with fractures of the inferior wall of one orbit. Fracture area, volume of displaced tissue, deviated IRM, and type of fracture were evaluated from coronal CT by one investigator. The association of those variables with the occurrence of eye symptoms (diplopia and enophthalmos) was assessed. Results: Of 45 patients, 27 were symptom-free (Group A) and 18 had symptoms (Group B) of enophthalmos and/or diplopia. In Group B, 12 had diplopia, one was enophthalmos, and five had both. By CT measurement, group A mean area was $192.6mm^2$ and the mean volume was $673.2mm^3$. Group B area was $316.2mm^2$ and volume was $1,710.6mm^3$. The volume was more influential on symptom occurrence. Each patient was categorized into four grades depending on the location of IRM. Symptom occurrence and higher grade were associated. Twenty-six patients had trap-door fracture (one side, attached to the fracture), and 19 had punched-out fracture (both sides detached). The punched-out fracture was more strongly associated with symptoms and had statistically significantly higher area and volume. Conclusion: In orbital trauma, measurement of fracture area and volume, evaluation of the deviated IRM and classification of the fracture type by coronal CT can effectively predict prognosis and surgical indication.

Nerve Injury from Overfilled Calcium Hydroxide Root Canal Filling Paste for Maxillary Lateral Incisor Endodontic Treatment (상악 측절치 근관치료 중 수산화칼슘 호제근충제 과충전으로 인하여 발생한 신경손상의 치험례)

  • Na, Kwang Myung;Kim, Jong-Bae;Chin, Byung-Rho;Kim, Jin-Wook;Kim, Chin-Soo;Kwon, Tae-Geon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.35 no.4
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    • pp.260-264
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    • 2013
  • Calcium hydroxide root canal filing paste (vitapex) is widely used as canal filling paste for infected canal. However, chemical burn is possible because of the high alkali base of calcium hydroxide. A 57-year old woman was admitted to our clinic for consistent dull pain and paresthesia in the left upper lip, zygoma and buccal cheek area, which developed during an endodontic treatment of the left lateral incisor. Radiographic finding showed radiopaque material, which exits from the left incisor root apex, and was within the left canine and first premolar buccal soft tissue. The overfilled Vitapex extended to the soft tissue was surgically curetted. The result of the surgical curettage was favorable. Though slight hypoesthesia on the upper lip was still remained, paresthesia on zygomatic and buccal cheek area was completely recovered. As far as we know, this is the first case report of infraorbital nerve damage from overfilled Vitapex material.

Failed septal extension graft in a patient with a history of radiotherapy

  • Kang, Il Gyu;Kim, Seon Tae;Lee, Seok Ho;Baek, Min Kwan
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.38
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    • pp.40.1-40.4
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    • 2016
  • Background: This report describes the authors' experience of "melting" septal cartilage after placement of a septal extension graft in a nasopharyngeal cancer patient that had been previously undergone radiation therapy, and provides a review of the literature. Methods: Electronic medical records were used to obtain details of the patient's clinical history. Results: A 32-year-old woman, who had previously undergone radiotherapy for nasopharyngeal cancer, visited our department to for rhinoplasty. Rhinoplasty was performed using a septal extension graft to raise the nasal tip (first operation). Five days after surgery, it was found that the septal extension graft was melting without any signs of infection, that is, the graft had softened, lost elasticity, thinned, and partially disappeared without any sign of infection at 5 days, and thus, the nasal tip was reconstructed with conchal cartilage (second operation). Five months after surgery, it was found that almost all septal cartilage had disappeared without any sign of infection, and thus, the entire nasal septum was reconstructed using 2-mm costal cartilage and an onlay graft was used for tip augmentation (third operation). Conclusions: After cartilage has been exposed to radiotherapy, its patency should be viewed with suspicion. Further studies are needed for determine the mechanism responsible for cartilage damage after radiotherapy.

DECOMPRESSION TREATMENT FOR ODONTOGENIC CYST IN MANDIBLE USING SPECIFIC DECOMPRESSION APPLIANCE : CASE REPORT (특별히 고안된 감압술 장치를 이용한 하악의 치성 낭종의 치료: 증례보고)

  • Kim, Kyoung-Soo;Kim, Jin-Cheol;Oh, Hae-Soo;Choi, Bin;Kil, Yong-Kab;Hong, Yong-Jae
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.29 no.2
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    • pp.182-186
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    • 2007
  • A cyst is a pathologic lesion characterized by a cavity filled with fluid, celluar products, air, or a combination of these. Dentigerous cysts were formed around the crown of unerupted teeth. The reduced enamel epithelium persists around the crown after it has formed. Proliferation of the epithelium in a fluid-filled sac may be induced by osmotic pressure. In the first decade the most frequent location is the premolar site. In each subsequent decade the largest number of cysts are in the mandibular third molar site, with the second most frequent site being the maxillary canine. The treatment of odontogenic cyst can be mostly classified into three types of cyst enucleation, marsupialization and decompression. We should consider age of patient, anatomic structure, location and size for choosing a treatment method. Advantage of cyst enucleation is fast healing, but a injury of a surrounding structure is highly. Marsupialization is conservative treatment that can reduce the damage of a adjacent structure, but it is only limited at superficial lesion. Decompression also is conservative treatment, but it has the difficulty of the oral hygiene and the troublesome of the lavage. We present the possibility that reduces the defect of decompression and cures the lesion efficiently. We report a male patient with the dentigerous cyst developed at left mandibular third molar in this study. We used the decompression for a treatment and created special appliance to treat the lesion efficiently. We report a case of the cyst treatment that is association with efficiency of decompression appliance.

Development of a Control Algorithm for Automatic Ventilation (환기창 자동제어용 제어 알고리즘 개발)

  • 박규식;이기명
    • Journal of Bio-Environment Control
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    • v.6 no.4
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    • pp.242-249
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    • 1997
  • Environmental control operations have been considerably contributed to the reduction of labor cost in both plastic film and glass greenhouses since government supported projects were begun. However, some problems are still remaining on the optimal environmental control and excessive operation due to an inflexible software regulating ventilation gear - reducers. The unadjustable software caused the damage of ventilation system, resulting in heat stresses of crops. This study was performed to develop a ventilation software controlling the vent opening level, opening sequence, based on the wind direction, and control interval according to the difference between ambient and set- up temperatures. The software included a beeper system alarming urgent cases, while a manager was remote from the greenhouse. A compatible hardware with the software was also developed by using a low-cost diffused DSP controller.

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SUGICAL TREATMENT OF MUCOSITIS AND FUNGAL INFECTION IN THE ACUTE LEUKEMIC PATIENTS (급성 백혈병 환자에서 점막 질환과 진균감염의 외과적 처치)

  • Ha, Won-Suk;Ye, Young-Geun;Park, Jae-Hong;Pyo, Sung-Un;Yun, Hyun-Jung;Lee, Sang-Hwa
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.28 no.2
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    • pp.172-177
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    • 2006
  • It is generally known that mucositis which often occur on hematopoietic disease patients, shows local necrosis of oral mucosa when the CBC is below the normal range. But sometimes, the lesions are occasionally infiltrate into adjacent tissue. When the pathologic destructive expansion is occurred, differential diagnosis with fungal infection, one of opportunistic infections, is needed. This means treatment and prognosis can be changed according to the diagnosis. So the diagnostic process is more important in this hematopoietic disease patients. In case of fungal infection, the range of tissue damage can expand broadly, and also proper antifungal agent and surgical extirpation should be done. After operation, continuous antifungal therapy and observations are needed. We made a comparative study of following 2 cases of fungal infection appeared on the acute lymphatic leukemia patients to discuss what the proper surgical treatment and medications are, and when the proper surgical intervention time is.