• The Korean Journal of Pain
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• v.8 no.2
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• pp.350-353
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• 1995

The first lesion in neural tissue produced by electrical currents were made in the 19th century by workers using direct current. In 1953, Sweet and Mark clearly demonstrated that DC lesions have unpredictable and ragged borders and may vary in size. They, as well as Hunsperger and Wyss, suggested that the use of high frequency currents might provide improved results and were proved correct. However, $Bovie^{(R)}$ electrosurgical unit may also be used in percutaneous medial branch neurotomy if a lesion made at a point or the dorsal surface of the transverse process just caudal to the most medial end of the superior edge of the transverse process (Bogduk's method). At this point the medial branch lies on the bone and its depth and medial displacement are defined by the bone which precludes the need for lateral radiographs to check placement. A lesion was made at same target point using the $Bovie^{(R)}$ electrosurgical unit in a 41 year male patient who had received a Kaneda operation because of L2 compression fracture. The patient was relieved of pain without any adverse effects.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.14 no.1_2
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• pp.65-76
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• 1992

This study was designed to observe the adaptive changes of mandibular condyles to displacement of mandibular condyle in adult animals. In this study, 16 rabbits weighting about 3.5 kg was selected. Four rabbits were preserved for control group and 8 animals were divided into 3 groups, 2 weeks, 4 weeks and 8 weeks. The experimental animals were performed oblique osteotomy on both mandibular ramus and internal wiring at mandibular border. The experimental animals were sacrificed consecutively on the 2 weeks, 4 weeks and 8 weeks after oblique osteotomy and mandibular condyles were dissected out carefully to produced tissue specimen. The specimens were fixed with 10% N formaline solution for 24 hours and rinsed with phosphate buffer solution. It was decalcified with 5% nitric acid for 15 days. Thereafter the specimens were dehydrated in alcohol series and embedded paraffin as usual manner. The mebedded specimen were sectioned in $4-6{\mu}m$ microtome, stained with hematoxylin-eosin and azan stain and observed through light microscope. The following results were observed from this experiment. When there was postional change of condyle head after mandibular ramus oblique osteotomy in adult rabbit, 1. The density of chondrocyte was generally increased at condylar cartilage and the thickness of condylar cartilage was increased posterosuperior aspect of the mandibular condyle slightly. 2. The density of chondrocyte was increased at proliferative zone so fibrous articular zone, porliferative zone and hypertrophic zone was clearly distinguished. 3. Active endochondral bone formation was occurred at mandibular condyle.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.6
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• pp.332-342
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• 2019

Objectives: Socket grafting is vital to prevent bone resorption after tooth extraction. Several techniques to prevent resorption have been described, and various bone graft substitutes have been developed and used with varying success. We conducted this pilot study to evaluate the performance of nanohydroxyapatite (nHA) derived from chicken eggshells in socket preservation. Materials and Methods: This was a prospective, single center, outcome assessor-blinded evaluation of 23 sockets (11 patients) grafted with nHA and covered with platelet-rich fibrin (PRF) membrane as a barrier. Bone width and radiographic bone density were measured using digital radiographs at 1, 12, and 24 weeks post-procedure. Postoperative histomorphometric and micro-computed tomography (CT) evaluation were performed. The study protocol was approved by the Institutional Ethics Committee. Results: All patients had uneventful wound healing without graft material displacement or leaching despite partial exposure of the grafted socket. Tissue re-epithelialized with thick gingival biotype (>3 mm). Width of the bone was maintained and radiographic density increased significantly with a trabecular pattern (73.91% of sockets) within 12 weeks. Histomorphometric analysis showed 56.52% Grade 3 bone formation and micro-CT analysis revealed newly formed bone with interconnecting trabeculae. Conclusion: Use of a PRF membrane with nHA resulted in good bone regeneration in sockets. Use of a PRF membrane prevents periosteal-releasing incisions for primary closure, thereby facilitating the preservation of keratinized mucosa and gingival architecture. This technique, which uses eggshell-derived nHA and PRF membrane from the patient's own blood, is innovative and is free of disease transfer risks. nHA is a promising economic bone graft substitute for bone regeneration and reconstruction because of the abundant availability of eggshell waste as a raw material.

• Korean Journal of Acupuncture
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• v.17 no.1
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• pp.67-73
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• 2000

The purpose of the present study is to determine the effect of Radix Stemonae on histamine induced tracheal smooth muscle contraction in guinea pigs. Guinea pig(500g, male) were killed by $CO_2$ exposure and a segment (8-10mm) of the thoracic trachea from guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine (His) which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for histamine ($10^{-7}∼10^{-4}M$). Contractions evoked by His ($ED_{50}$) were inhibited significantly by Radix Stemonae. In guinea pig tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was 87.4% (p<0.01) after $100{\mu}l/ml$ Radix Stemonae. Following treatment with propranolol, the mean percent inhibition caused by $100{\mu}l/ml$ Radix Stemonae fell to 16.2% in guinea pig induced by histamine contraction. Indomethacin and methylene blue($10^{-7}M$) did not significantly alter the inhibitory effect of Radix Stemonae. These results indicate that Radix Stemonae can relax histamine induced contraction of guinea pig tracheal smooth muscle, and that this inhibition involves sympathetic effects.

• Journal of Korean Foot and Ankle Society
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• v.6 no.2
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• pp.201-207
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• 2002

Purpose: To present the clinical analysis of the results obtained in 38 cases of displaced intraarticular calcaneal fractures undergone combined percutaneous axial pin fixation of calcaneal body and minimal internal fixation using extensile lateral approach. Materials and Methods: From March 2000 to February 2002, thirty-eight displaced intraarticular fractures of the calcaneus in 35 patients were fixed with 3.5mm cannulated screws and percutaneous 2.5mm K-wires. The extensile lateral approach was used in all cases. The average follow-up period was 16 months. Clinical evaluation was assessed according to the Ankle-Hind Foot Scale of American Orthopedic Foot and Ankle Society. Results: The clinical results were graded as excellent in 8 cases(21%), good in 22 cases(58%), fair in 6 cases(16%), and poor in 2 cases(5%). Two cases of poor result were type IV of Sanders classification. The postoperative reduction status of the articular surface was analyzed by computed tomography in all cases and was found to be less 2mm of step off in 30 cases and between 2 and 4mm in 8 cases. Unsatisfactory results were correlated with severity of articular comminution and failure to obtain accurate reduction of the articular surface. Using early functional postoperative care, all fractures healed without secondary displacement except 1 case on an average of ten weeks. Two cases had superficial necrosis of the wound margins, however, secondary wound healing was uneventful and skin grafting was not needed. Conclusion: Combined minimal internal fixation and percutaneous pin fixation using extensile lateral approach is useful operative method of intraarticular calcaneal fractures because providing enough stability to permit functional aftercare and allowing excellent anatomical reduction. In addition, this method diminishes the risk of lateral soft tissue problems.

• The Journal of Korean Academy of Prosthodontics
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• v.31 no.3
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• pp.351-384
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• 1993

Complete denture occlusion must be developed to function efficiently and with the least amount of trauma to the supporting tissues. For the preservation of supporting tissues, it is imperative to reduce to a minimum the functional stress induced by dentures. The magnitude of the horizontal component of functional stress contributed by various occlusal teeth forms has not been studied. This study was aimed to investigate the influence of different occlusal teeth forms on the mode of distribution of the stresses in the mandibular tissue, and the displacement of lower dentures during the variant functional movement of mandible for this study three dimensional finite element analysis was used. FEM models were created using commercial software Super Sap for IBM 32 bit computer. The model was composed of 3380 brick elements and 4346 nodes. The results were as follows. 1. The magnitude of stress was similar between two models in centric occlusion, in the case of anatomic model, the stress was concentrated on the buccal side of alveolar ridge beneath the bicuspids. 2. During the protrusive movement, the increasing of stress from the posterior to anterior part of mandible was seen in the case of anatomic model. 3. During the lateral movement, the stress of anatomic model was greater than that of nonanatomic model. 4. The stress of anatomic model was concentrated on the anterior region of residual ridge during the lateral movement. 5. In the case of anatomic model the anterior part of denture was displaced severely at the centric and lateral position, but the denture of nonanatomic model was displaced minutely at the protrusive and lateral position.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.1
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• pp.55-61
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• 2000

The present study was conducted to investigate the possible role of the sympathetic nervous system in two-kidney, one clip (2K1C) and deoxycorticosterone acetate (DOCA)-salt hypertension. 2K1C and DOCA- salt hypertension were made in Sprague-Dawley rats. Four weeks after induction of hypertension, systolic blood pressure measured in conscious state was significantly higher in 2K1C $(216{\pm}18\;mmHg)$ and DOCA-salt $(205{\pm}29\;mmHg)$ groups than that in control $(128{\pm}4\;mmHg).$ The third branches (＜300 ${\mu}m$ in outer diameter) of the mesenteric artery were isolated and cut into ring segments of $2{\sim}3$ mm in length. Each ring segment was mounted in tissue bath and connected to a force displacement transducer for measurement of isometric tension. The arterial rings were contracted by application of norepinephrine (NE) in a dose-dependent manner. The amplitude of the NE-induced contraction of the vessels was significantly larger in hypertension than in control. The NE-induced contraction was significantly enhanced by neuropeptide Y (NPY) in hypertension. Reciprocally, NPY-elicited vasocontraction was increased by NE in hypertension. These results suggest that the sympathetic nervous system contributes to the development of 2K1C and DOCA-salt hypertension.

• The Journal of Internal Korean Medicine
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• v.18 no.2
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• pp.83-93
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• 1997

Rhizoma Coptidis, a traditional herb medicine, has been used in Korea and China for many centuries as a treatment for many disease. The purpose of the present study was to determine the effect of Rhizoma Coptidis on histamine-induced tracheal smooth muscle contraction in guinea pigs and rats. Guinea pigs(500g, male) and rats(250g, male) were killed by $CO_2$ exposure and a segment (8-10mm) of the thoracic trachea from each guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for histamine ($10^{-7}-10^{-3}M$). Contractions evoked by histamine($ED_{50}$) were inhibited significantly by Rhizoma Coptidis. The mean percent inhibition was 33.2% after 1.5mg/ml Rhizoma Coptidis, and 69.5% after 5.0mg/ml Rhizoma Coptidis in guinea pigs, and the mean percent inhibition was 25.3% after 1.5mg/ml Rhizoma Coptidis, and 65.8% after 5.0mg/ml Rhizoma Coptidis in rats. Indomethacin ($10^{-7}M$) slightly but significantly attenuated the inhibitory effects of Rhizoma Coptidis. But propranolol and methylene blue ($10^{-7}M$) did not significantly alter the inhibitory effect of Rhizoma Coptidis. These results indicate that Rhizoma Coptidis can relax histamine-induced contraction of guinea pig and rat tracheal smooth muscle, and that this inhibition involves, in part, cyclooxygenese inhibitor.

• Archives of Craniofacial Surgery
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• v.14 no.1
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• pp.61-64
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• 2013

Schwannomas are well-differentiated solitary benign tumors that originate from the schwann cells of the nerve sheath. They can readily occur in the head and neck regions, but the schwannoma originating from the infraorbital nerve is extremely rare and usually painless, slow-growing, and without specific symptoms. The author experienced a rare case of infraorbital schwannoma, which was completely removed through the intraoral approach. A 20-year-old woman was admitted to our hospital for a painless, solid and circular mass located on the right infraorbital region. The eyeball movement and visual field were normal. There was no globe displacement or proptosis. Preoperative computed tomography demonstrated $13{\times}10{\times}5mm$-sized soft tissue mass. On March 2011, the mass was removed through an intraoral approach. On histopathological examination, the gross specimen consisted of a smooth, well-encapsulated and light yellowish solid mass, measuring $12{\times}7{\times}5mm$. Microscopically, it presented a typical manifestation of schwannoma with Antoni A area with Verocay body, and Antoni B area on H&E stain. The result of the immunohistochemical staining was positive for the S-100 protein. The patient had hypoesthesia of the nasal septum and vestibule in the postoperative period, and this finding confirmed that the internal nasal branch of infraorbital nerve was the nerve in which the schwannoma originated. Infraorbital schwannomas are very rare and must be included in the differential diagnosis of the orbital masses inferior to the eyeball. In the case of early diagnosis, the small-sized infraorbital schwannomas can be completely removed without any scar through an intraoral approach.

• Journal of Korean Neurosurgical Society
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• v.64 no.4
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• pp.585-591
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• 2021

Objective : Filum transection is one of the most commonly performed operative procedure in pediatric neurosurgery. However, the clinical and pathological features as well as the surgical indication are not well-established. This study aimed to analyze the characteristics of patients who underwent transection of the filum during the last 10 years in a single institute. Methods : A total of 82 patients underwent transection of the filum during the period. As a general rule, we performed the transection in patients who are symptomatic or have abnormality in the urologic or neuromuscular evaluations. There were exceptions as asymptomatic patients who only fit the definition of thickened filum (width greater than 2.0 mm or conus level below L3 vertebral body) were operated by parent's wish or surgeon's preference according to radiological findings, etc. Results : Seventy-six out of 82 patients had fibrous tissue in the pathologic specimen of filum. Interestingly, patients who had glial cells were more correlated with no preoperative syrinx, and no progression of syrinx even for those who did have syrinx initially. Also, larger percentage of symptomatic patients had peripheral nerve twigs than asymptomatic patients. No difference in conus level or thickness of filum was found between patients with or without preoperative syrinx. Significantly more patients with syrinx (56%) were chosen to be operated without any symptom or abnormality in study i.e., solely based on radiological findings than those without syrinx (21%). The surgical outcome for syrinx was favorable, as all but one patient had either improved or static syrinx. The exceptional case had increase in size due to the upward displacement of the proximal end of the cut filum. Conclusion : This study evaluated the pathological, clinical, radiological features of patients who underwent transection of the filum. Interesting correlations between pathological findings and clinical features were found. Excellent outcome regarding preoperative syrinx was also shown.