• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.3
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• pp.169-174
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• 2002

Purpose: Irradiation in the oral cancer patients causes early and late complications such as intraoral mucositis and fibrosis, with a various expression of GM-CSF and TGF-${\beta}1$. The purpose of this study was to investigate the production of GM-CSF and TGF-${\beta}1$ by the irradiated human gingival fibroblasts cultivated with lipopolysaccharide. Materials and Methods: Irradiated (total dose, 60 Gy) human gingival fibroblasts were incubated with LPS. Culture supernatants that were collected at 24, 48, and 72 hours were assessed for GM-CSF and TGF-${\beta}1$ by enzyme-linked immunosorbent assay. Results: 1. GM-CSF production in nomal gingival fibroblasts was increased with incubation time, but decreased with incubation time in irradiated gingival fibroblasts. GM-CSF production in both normal and irradiated gingival fibroblasts induced with LPS was higher than the control. 2. TGF-${\beta}1$ production in normal gingival fibroblasts was decreased after 24 hours, but, it was increased until 48 hours in irradiated gingival fibroblasts. TGF-${\beta}1$ production in normal gingival fibroblasts exposed with LPS was higher than the control. Conversely, It was lower than the control in irradiated gingival fibroblasts exposed with LPS. Conclusion: This indicates that irradiation in gingival fibroblasts may play an important role in radiation-induced intraoral mucositis and fibrosis. However, LPS decreases the production of TGF-${\beta}1$ in the irradiated gingival fibroblasts.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.3
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• pp.175-181
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• 2002

Intermaxillary fixation and occusal splint are routine procedure for maxillofacial fracture and orthognathic surgery. When these methods could obstruct oral airway the patients who kept intermaxillary fixation and occusal splint in their mouth, are very difficult to breath after surgery. Nasal bleeding and pharyngeal edema due to nasotracheal intubation, residual effect of muscle relaxants, and anesthetic agent could be contributing factor of airway obstruction. In this study, pulmonary function test was evaluated before and after intermaxillary fixation, and intermaxillary fixation with occusal splint in 22 volunteers. The results were as follows 1. FVC, %FVC, $FEV_1$, $FEV_1%$, PEF, $PEF_{50}$, MVV without intermaxillary fixtion were 4.45L, 88%, 4.03L, 90.9%, 10.26L/s, 5.53L/s, and 136.14L/min, and with intermaxillary fixation were 3.51L, 68.67%, 3.06L, 69.39L, 6.52L/s, 3.94L/s, and 69.39L/min. The results with intermaxillary fixation and occusal splint were 2.15L, 42.41%, 1.71L, 38.81%, 2.83L/s, 1.74L/s, and 37.14L/min. 2. Compared with before and after intermaxillary fixation, all values of pulmonary function test were decreased and after intermaxillary fixation and intermaixillary fixation with occulasal splint, the results were decreased. 3. MVV and PEF were decreased significantly with interaxillary fixtion and occusal splint, and FVC was less decreased. It meant that intermaxillary fixation and occluasal splint induced reduction of respiratory flow significantly, but less reduction of respiratory volume. 4. Intermaxillary fixation and occulsal splint induced increase of airway resistance, decrease of expiratory volume and air flow. So severe respiratory difficulty could be seen to all volunteers who kept intermaxillary fixtion and occusal splint. 5. In classification of respiratory difficulty, intermaxillary fixation with occulsal splint induced complex respiratory difficulty more than intermaxillary fixation only did. From the above results, doctors who care patients kept intermaxillary fixation and occusal splint should be aware of respiratory depression caused by these treatment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.3
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• pp.196-204
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• 2002

For the study of its stability when the screw has been fixed after sagittal split ramus osteotomy(SSRO) of the mandible, the methods of screw arrangement are classified into two types, triangular and straight. The angles of screws to the bone surface are classified as perpendicular arrangements, the $60^{\circ}$ anterioinferior screw, known as triangular, and the most posterior screw, called straight arrangement, thus there are four types. The finite element method model has been made by using a three dimensional calculator and a supercomputer. The load directions are to the anterior teeth, premolar region, and molar region, and the bite force is 1 Kgf to each region. The distribution of stress, the von-Mises yield strength, and safety of margin refer to the total sum of transformed energy have been studied by comparison with each other. The following conclusion has been researched : 1. When shear stress is compared, in the triangular arrangement in the form of "ㄱ", the anterosuperior screw is seen at contributing to the support of the bone fragment. In the straight arrangement, substantial stress is seen to be concentrated on the most posterior angled screw. 2. When the von-Mises yield strength is compared, it seemed that the stress concentration on the angled anteroinferior screw is higher, it shows a higher possibility of fracture than any other screw. In the straight arrangement, stress appeared to be concentrated on the most posteriorly angled screw. 3. When the safety margins of the transfomed energy are compared, the energy conduction is much greater in the case of the angled screw than in the case of the perpendicular screw. The triangular arrangement in the form of "ㄱ" shows a superior clinical sign to that of the straight arrangement. Judging from the above results, when the screw fixation is made after SSRO in practical clinical cases, two screws should be inserted in the superior border of mandibular ramus and a third screw of mandibular inferior border should be inserted in the form of triangular. All screws on the bony surface should be placed perpendicularly-$90^{\circ}$ angles apparently best promote bony support and stability.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.1
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• pp.5-17
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• 2000

To evaluate the possible therapeutic effects of growth hormone and vitamin C on multiorgan failure, a rat model was developed for LPS-induced sepsis. Using this model, the effects of growth hormone and vitamin C on tissue damages, catalase and i-NOS activities, and MDA levels were examined in the lung and liver. The level of TNF- in plasm was also examined. Male, Sprague-Dawley rats were injected with LPS intraperitoneally then divided into 3 groups : positive controls injected with LPS only, the ones injected with growth hormone or vitamin C immediately after the LPS injections. The lung and the liver were then isolated, blood samples were collected at 24 or 48 hours after the LPS injection, then examined for histopathological and biochemical changes. The results obtained were as follows. 1. LPS induced sinusoid vasodilation and mild destruction of lobular structure in the liver. In the lung, alveolar structure appeared to be thickened and interstitial edema was observed. The levels of MDA in the liver and the lung was increased by LPS, while the activity of catalase was decreased. The activity of i-NOS of those tissues was also increased, which was more pronounced at 24 hr. The level of TNF- in plasm was increased by LPS 2. In the lung, vitamin C suppressed lymphocyte and neutrophil infiltration, alveolar wall thickening and interstitial edema. In the liver, vitamin C protected against the destruction of the lobular structure. The activity of catalase reduced by LPS was reversed partly by vitamin C. The activity of i-NOS enhanced by LPS was also reversed by vitamin C. The level of TNF- in plasm reduced in some animals by vitamin C, which however was not significant statistically(p<0.05). 3. Growth hormone showed similar protective effects against inflammation and damages in the liver and lung tissues. Growth hormone reversed partly the LPS effects on the level of MDA, the activity of catalase and i-NOS induction in the liver and the lung. Growth hormone reduced plasma level of TNF-${\alpha}$ substantially, which contrasted from vitamin C. Besides this, overall protective effects of growth hormone against LPS-induced experimental sepsis were similar to those of vitamin C. From this results, the mechanism of growth hormone on suppression of LPS-induced tissue damage might be associated with production of antioxidative enzyme and suppression of plasma TNF- level.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.1
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• pp.24-39
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• 2000

Various methods and graft materials have been used to fill in the defect adjacent to the implants and considered as clinically acceptable. But it is not clear whether the regenerated bone increases the implant-bone contact and supports the implant. The purpose of this study is to evaluate regenerated bone surrounding implants using bone morphogenetic protein(BMP) and demineralized freeze-dried bone(DFDB), and the interfaces between implants and regenerated bone. bBMP was extracted and partially purified from the bovine bone matrix using heparine chromatography. Demineralized freeze-dried bone was made from the dog. Inactive insoluble collagenous bone matrix(IBM) of dog was used as carrier of bBMP. Interfaces of titanium coated epoxy resin implants were processed for demineralized section for transmission electron microscopy(TEM) and those of screw type implants were for nondemineralized section for light and fluoromicroscopic examination. Implants were inserted in the inferior border of mandible of adult dogs and artificial bony defects($3{\times}3{\times}4mm$) were made at the mesial and distal side of implants. Defects were filled with BMP(BMP group) and DFDB(DFDB group). For the fluoromicroscopic examination, the fluorescent dyes(oxytetracycline, calcein green, alizarin red) were injected 2, 4, 6, 8, 12 weeks after implantation. The experimental animals were sacrificed at the 6th and the 12th week and their mandible were extirpated and processed for examination with light microscopy, fluoromicroscopy and TEM. The obtained results were as follows : 1. By the light microscopic findings, the defects were filled with woven bone at the 6th week and compact bone at the 12th week, and the osseointegrations were seen in both groups. There was no histological difference between them. 2. On the basis of the histomorphometric analysis, BMP group(6th week: 40.25%, 12th week: 56.04%) had higher bony contact ratio than DFDB group(38.37%, 42.63%). There was significant difference between two groups at the 12th week(p<0.05). 3. The amount of bone formation in BMP group was more prominent than in DFDB group. Significant difference was noted among two groups at the 6th and the 8th week(p<0.05). 4. By the transmission electron microscopic findings, $0.4-2{\mu}m$ soft tissue layer was found in adjacent to the interfaces and over the collagen fibrils of bone at the 6th week. However, about 100nm amorphous layer was noted at the interface or collagen fibrils directly extended to the titanium surface at the 12th week. There was no significant difference between two groups. 5. These results suggest that BMP and DFDB can be used as good graft materials in the regeneration of bone adjacent to implant, and BMP is more valuable as a bone inducer than DFDB.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.1
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• pp.85-92
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• 2000

Common dental procedures(dental extraction & minor operation) are potentially stress-inducing in many patients, especially medically compromised patients. The body's response to dental stress involves the cardiovascular system(an increase in cardiovascular workload), the respiratory organ and the endocrine system(change in metabolism). To minimize the stress to the medical risk patient, the stress reduction protocol was established. The obtained contents were as follows: (1) Recognize the patient's degree of medical risk (2) Complete medical consultation before dental therapy (3) Schedule the patient's appointment in the morning (4) Monitor and record preoperative and postoperative vital signs (5) Use psychosedation during therapy (6) Use adequate pain control during therapy (7) Short length of appointment : do not exceed the patient's limits of tolerance (8) Follow up with postoperative pain/anxiety control (9) Telephone the higher medical risk patient later on the same day that treatment was given Though the stress reduction protocol above was applied to the dental extraction in medically compromised patients with the advanced infected teeth, the final responsibility for the complications(syncope, bleeding & infection, etc.) in a patient rests with the dentist who ultimately treats him. For the prevention of postextraction complications & poor prognosis, the authors treated the advanced infected teeth with the pulp extirpation, opening drainage through the canal and complete occlusal reduction. The final extraction and wound closure were then done after $1{\sim}2$ weeks. The final prognosis was comfortable without common complications.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.1
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• pp.46-54
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• 2005

Purpose: This study was performed in order to compare the osseointegration of 4 different surfaced implants in the dog's tibia which has thick dense cortical bone and loose marrow space. Materials & methods: Four mongrel dogs and four different surface types of implants, smooth surfaced AVANA implants, RBM surfaced AVANA implants, HA-coated Steri-Oss implants and SLA Bicon implants, were used in this study. The animals were divided into 4 groups on the basis of implant surface characteristics: Control group, RBM group, HA group, and SLA group. Three implants of each group were installed into the metaphysis of tibia of adult dogs. The animals were sacrificed at 8 weeks after implantation. The undecalcified specimens were prepared for histological examination and histomorphometric analysis of implant-bone contact ratios. Results: Radiographically and histologically good osseointegration of implant was observed in the dense cortical bone, but poor osseointegration was observed in the marrow space. Histologically more bone apposition to implant surface was found in rough surfaced groups than the smooth surfaced, Control group. In histomorphometric findings of cortical bone the average bone-implant contact ratios of HA group (95.4%, p<0.01), RBM group (87.1%, p<0.05), and SLA group (86.0%, p<0.05) were significantly higher than that of Control group (75.9%). In marrow space the average bone-implant contact ratios of HA group (76.1%, p<0.01) and SLA group (45.4%, p<0.05) were significantly higher than that of Control group (29.6%). The ratio of RBM group was higher than that of Control group but there was no significantly difference between RBM group and Control group. Conclusion: These results suggest that the rough surfaced implants can obtain the better osseointegration than the smooth surfaced implant in the cortical and marrow space and that HA-coated implants can obtain the best osseointegration in the marrow space among them.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.1
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• pp.69-75
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• 2006

Head and neck squamous cell carcinoma(HNSCC) is the sixth most common cancer among men in the developed world affecting the tongue, pharynx, larynx and oral cavity. HNSCC is thought to represent a multistep process whereby carcinogen exposure leads to genetic instability in the tissue and accumulation of specific genetic events, which result in dysregulation of proliferation, differentiation, and cell loss and the acquisition of invasive capacity. Despite therapeutic and diagnostic progress in oncology during the past decades, the prognosis of HNSCC remains poor. Thus it seems that finding a biological tumor markers which will increase the early diagnosis and treatment monitoring rates, is of paramount importance in respect to improving prognosis. In an effort to identify gene expression signatures that may serve as biomarkers, this study several genes were selected, such as H3,3A, S100A7, UCHL1, GSTP1, PAI-2, PLK, TGF${\beta}$1 and bFGF, and used 7 HNSCC cell lines that were established various anatomical sites, and also 17 other cancer cell lines were used for control group using real-time quantitative RT-PCR and immunocytochemical analysis with a monoclonal antibody. In this study, S100A7 showed a clearly restricted occurrence in tongue originated cell line, and GSTP1 expression level in the pharynx originated cell line was very increased, relative to corresponding other cell lines. These results suggest that S100A7 and GSTP1 genes' expression can occur during tongue and pharynx originated head and neck tumorigenesis and that genetic change is an important driving force in the carcinogenesis process. This data indicate that S100A7 and GSTP1 expression pattern in HNSCC reflect both diagnostic clue and biological marker. And this is provides a foundation for the development of site-specific diagnostic strategies and treatments for HNSCC.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.1
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• pp.36-41
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• 2006

Objective. The objective of this study was to examine the hypothesis that inflammatory synovial fluid from TMJ internal derangement initiates a transient increase in intracellular calcium concentration ([$Ca^{2+}$]i) in chondrocytes and the induced Ca2+ signaling affects iNOS/COX-2 gene expression patterns following exposure to inflamed synovial fluid. Materials and Methods. Two female adult patients with symptoms of TMD who agreed to participate in the study were selected for this study. Immortalized human juvenile costal chondrocyte C-28/I2 was grown to 80% confluency and synovial fluids from two patients were added respectively to culture media for 24 hours at the concentration of 100ng/10ml. Confocal laser scanning microscope (CLSM) was used to examine changes of intracellular calcium concentration ([$Ca^{2+}$]i). RT-PCR was performed to identify the expression profile of IL-1${\alpha}$, iNOS, COX-2. Results. Increased [$Ca^{2+}$]i was observed in chondrocytes subjected to inflamed synovial fluid compared to control cultures and in respective cultures exposed to inflamed synovial fluids from each patient, IL-1${\beta}$, COX-2 mRNA were detected. However, in neither case iNOS mRNA was expressed. IL-1${\alpha}$, COX-2, and iNOS mRNA were expressed in control culture. Conclusion. Our results show that immortalized chondrocytes cultured with inflamed synovial fluids from patients diagnosed as disc displacement without reduction and limitation in mouth opening showed increased calcium concentration and expression of COX-2 while inhibiting the production of iNOS, which in turn could adversely affect the chondrocytes in at least short term by hindering physiologic role of NO against inflammatory cascades. These findings suggest that inflamed synovial fluid may differentially regulate the transcriptomes of relevant inflammatory mediators, especially iNOS/COX-2 axis in chondrocytes through adjusting calcium transients.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.1
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• pp.8-18
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• 2006

Purpose: The purpose of this study was to verify that the expressions of angiogenin, transforming growth factor-beta(TGF-${\beta}$), vascular endothelial growth factor(VEGF), human apurinic/apyrimidinic endonuclease(APEX) and tumor necrosis factor-alpha(TNF-${\alpha}$) were associated with the tumorigenesis of the oral squamous cell carcinoma(OSCC). Materials and Methods: Fifty-one samples of OSCC and fifteen normal oral mucosae were obtained to analyze the expression levels of above five factors. mRNA expressions were quantified by the quantitative competitive PCR(QC-PCR) method. After 2% agarose gel electrophoresis stained with ethidium bromide, the concentration of mRNA was calculated by a digital image analysis system. The expression levels of angiogenin, TGF-${\beta}$, VEGF, APEX and TNF-${\alpha}$ were compared by unpaired Student's t-tests between cancer and normal tissues. We analyzed statistically to find the cut-off values that would be useful as diagnostic markers, and the linear regression analysis between every two factors of these five factors by SAS system. Results: All of these five factors (angiogenin: P<0.0037, TGF-${\beta}$: P<0.0001, VEGF: P<0.0102, APEX: P<0.0023, TNF-${\alpha}$: P<0.0074) were significantly correlated with OSCC. In the analysis to find the cut-off values for the diagnosis, we could not find any value that had a reasonable sensitivity and specificity. In the linear regression analysis, there were correlations between angiogenin and TNF-${\alpha}$, TGF-${\beta}$ and VEGF, TGF-${\beta}$ and APEX, TGF-${\beta}$ and TNF-${\alpha}$, VEGF and APEX, VEGF and TNF-${\alpha}$, APEX and TNF-${\alpha}$. Conclusion: Our results suggest that not only angiogenin, TGF-${\beta}$, VEGF, APEX and TNF-${\alpha}$ are significantly associated with the tumorigenesis, but also the close relationship between these factors might enhance the tumorigenesis of OSCC. We can not find clinical availability for diagnosis.