• Journal of Korean Dental Science
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• 제2권2호
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• pp.12-17
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• 2009

Purpose : To determine whether peri-implant crestal bone loss could be affected by systemic disease, primary ISQ value, implantation method (submerged vs. non-submerged), surface treatment, and bone density Materials and methods : Patients who underwent fixture installation from June 24, 2005 to October 23, 2008 at Seoul National University Bundang Hospital were evaluated. A total of 157 patients (male: 52, female: 85) had 346 fixtures installed. Among them, 49 patients had periapical radiographs taken 1 year after prostheses were first set. A total of 97 fixtures were implanted. In particular, 30 fixtures were installed in patients with systemic diseases such as diabetes mellitus, cardiovascular disease, hypertension, and liver disease. The immediate stability of implants was measured with $Osstell^{tm}$. Implant surface treatment was classified into two groups (RBM, Cellnest (Anodized)), and bone density, into four groups (D1~D4). The bone resorption on the mesial and distal areas of fixtures was measured with periapical radiographs using the paralleling technique, and the mean value was calculated. The length determination program in IMPAX (AGFA, Belgium) was used. Results : At least 332 out of 346 (96%) installed GS II implants were successfully osseointegrated 1 year after prostheses were first set. The mean value of the bone resorption of the installed GS II implants was 0.44mm. The minimum value was 0mm, and the maximum value, 2.85mm. There was a statistically significant difference between the implantation methods (submerged, non-submerged) with regard to the amount of alveolar bone loss 1 year after prostheses were first set (p<0.05). Non-submerged implants showed less crestal bone loss. Note, however, that other variables had no correlation with crestal bone loss (p>0.05). Conclusion : There was a statistically significant difference between the 1-stage method and 2-stage method with regard to the amount of alveolar bone loss 1 year after prostheses were first set. Systemic disease, primary ISQ value, surface treatment, and bone density were not associated with alveolar bone loss. Other variables were assumed to have a correlation with alveolar bone loss.

• 대한소아치과학회지
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• 제24권1호
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• pp.204-219
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• 1997

The use of fluoride is one of the most effective methods for caries prevention. Fluoridation of public water supply has been recognized, for many years, as an effective way to reduce dental caries. The fluoride supplement has been recommended when the natural fluoride was unavailable or below the optimal range. However the mechanism of caries prevention by fluoride has not yet been clarified and it is well known that an overdose of fluoride results inacute and chronic toxicity, especially dental fluorosis. Fluoride mouthrinsing solution is widely used in dentistry due to its effectiveness in carrying anticariogenic action. Understanding the effects of fluoride mouthrinsing solution on human gingival fibroblasts will provide the safety rationale for its use during the caries preventive therapy. The purpose of this study was to evaluate the cytotoxic effect of fluoride mouthrinsing solution on the human gingival fibroblast in vitro. The human gingival fibroblasts were cultured from healthy gingiva on the extracted deciduous teeth of children. Cells were inoculated into a 24-well plate with $1{\times}10^4cells/well$ of medium at $37^{\circ}C$, 100% humidity, 5% $CO_2$ incubator for 24 hours. And the cells were counted by using the hemocytometer at each designed study. Human gingival fibroblasts were cultured in growth medium after one minute application range of 0.02%-0.2% NaF solution and 0.1% $SnF_2$ solution. The cells used in this study were between fifth to eighth passage number. The cell morphology was examined by inverted microscope and cell proliferation was measured by incorporating $[^3H]$-thymidine into DNA. DNA synthesis by human gingival fibroblasts was assessed by $[^3H]$-thymidine uptake assays while the cell activity was measured by MTT assay. Each concentrated fluoride mouthrinsing solution was estimated for its biocompatability with fibroblasts by the tissue culture technique. The results of this study were as follows : 1. It was observed that at 0.05%, 0.2% NaF mouthrinsing solution the cytoplasmic processes became globular. When 0.1% $SnF_2$ mouthrinsing solution was applied, the cytoplasmic process and cell morphology were disappeared. 2. DNA synthetic activity was reduced regardless of the concentration of the fluoride mouthrinsing solution. However, the result is statistically insignificant except 0.1% $SnF_2$ mouthrinsing solution(p<0.05). 3. Our results indicate that 0.02%, 0.05% concentrations of NaF mouthrinsing solution caused minimal cytotoxicity. But 0.2% NaF and 0.1% $SnF_2$ concentration were a significant difference between the cell activity in the experimental group and control group (p<0.05). 4. After appling 0.05% & 0.02% NaF fluoride mouthrinsing solution, cell activity was restored to the control groups level according to incubating time. The results suggest that direct exposure to fluoride solution inhibits gingival fibroblast activity. Therefore, for the most effective use of fluoride use, lowering the concentration of fluoride mouthrinsing is advisable because it maintains biocompatability and free ion in the oral fluid.

• 대한치과교정학회지
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• 제30권2호
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• pp.245-260
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• 2000

본 연구는 인터넷상의 가상공간에 다양한 자료로 구성된 환자 증례를 통해, 교정을 배우고자 하는 임상의나 학생들의 교육에 필요한 멀티미디어 데이터베이스를 구축하기 위한 것이다. 이러한 시스템을 구현하기 위해서는 이미지 자료의 처리, computer network를 통한 빠른 정보처리 기능, 진단 분석법의 개발, 데이터베이스의 구축 기술, 데이터베이스와 인터넷과의 연계, 증례를 통한 교육방법론과 같은 기술적 문제점들이 있다. 진단과 치료계획을 위한 분석은 모델 분석과 두부방사선 사진분석으로 나누어 제공하였다. 모델분석법은 arch length discrepancy와 Bolton tooth ratio를 환자 정보란에 제공하였다. 두부방사선 사진분석은 초진란에 제공하였다. Cephalometric analysis ver 2.0과 Power Ceph pro 3.3.5를 이용하여 Tweed, Steiner, Jarabak분석법 등을 제공하였으나, 본문에서는 주로 Kim's analysis와 몇 가지 계측치를 추가하여 설명하였고, 나머지는 tracing란에서 제시하였다. 또한 치료 종료 후나 보정란에서 치료 전,후의 두부방사선 사진을 중첩해서 보여줌으로써 치료에 의한 효과를 직접 볼 수 있도록 하였다.

• 대한약리학회지
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• 제24권1호
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• pp.43-52
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• 1988

국소마취제의 약리학적 작용기전을 탐구키 위하여 소의 신선한 대뇌피질로부터 synaptosomal plasma membrane vesicles(SPMV)를 분리한 후 그 소수성 중심부의 microviscosity에 미치는 국소마취제의 영향을 pyrene 형광 probe법으로 측정한 결과 lidocaine HCI과 procaine HCI이 microviscosity를 낮춘다는 것을 알았고 그 정도는 procaine HCI에 비하여 tidocaine.HCI이 더욱 컸다. 또 국소마취 제 가 dimyristoylphosphatidylcholine (DMPC) multilamellar liposomes의 상전 이온도를 낮추며 cooperative unit크기를 감소시킨다는 것도 시차 열량분석법으로 알게 되었다. 상전이온도와 cooperative unit 크기의 감소 정도는 dibucaine HCI>tetracaine HCI>lidocaine HCI > procaine HCI의 순이었다.

• Archives of Pharmacal Research
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• 제20권1호
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• pp.1-6
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• 1997

We determined the microviscosity of synaptosomal plasma membrane vesicles (SPMV) isolated from bovine cerebral cortex and liposomes of total lipids (SPMTL) and phospholipids (SPMPL) extracted from SPMV. Changes in the microviscosity induced by the range and rate of lateral diffusion were measured by the intramolecular excimerization of 1, 3-di(1-pyrenyl)propane (Py-3-Py). The microviscosity values of the direct probe environment in SPMV, SPMTL and SPMPL were 38.17, 31.11 and 27.64 cP, respectively, at$37^{\circ}C$and the activation energies $(E_a)$ of the excimer formation of Py-3-Py in SPMV, SPMTL and SPMPL were 8.236, 7.448 amd 7.025 kcal/mol, respectively. Probe location was measured by polarity and polarizability parameters of the probe Py-3-Py and probe analogues, pyrene, 1-pyrenenonanol and 1-pyrenemethyl-3${\beta}$-hydroxy-22, 23-bisnor-5-cholenate (PMC), incorporated into membranes or solubilized in reference solvents. There existed a good linear relationship between the first absorption peak of the $^1_a$ band and the polarizability parameter $(n^{2}-1)/(2n^{2}+1)$.The calculated refractive index values for SPMV, SPMTL and SPMPL were close to 1.50, which is higher than that of liquid paraffin (n=l.475). The probe location was also determined by using a polarity parameter $(f-1/2f^{I})$. Here f=$({\varepsilon}-1)/(2{\varepsilon}+1)$ is the dielectric constant function and $f^I=(n^2-1)/(2n^2+1)$ is the refractive index function. A correlation existed between the monomer fluorescence intensity ratio and the solvent polarity parameter. The probes incorporated in SPMV, SPMTL, and SPMPL report a polarity value close to that of 1-hexanol $({\varepsilon}=13.29)$. In conclusion, Py-3-Py is located completely inside the membrane, not in the very hydrophobic core, but displaced toward the polar head groups of phospholipid molecules, e.g., central methylene region of aliphatic chains of phospholipid molecules.

• Macromolecular Research
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• 제9권2호
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• pp.107-115
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• 2001

Poly(L-lactide-co-glycolide)(PLGA) was blended with poly[$\omega$-methacryloyloxyethyl phospho-rylcholine-co-ethylhexylmethacrylate (PMEH)] (PLGA/PMEH) to endow with new functionality i.e., to improve the cell-, tissue- and blood-compatibility. The characteristics of surface properties were investigated by measurement of contact angle goniometer, Fourier-transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR) and electron spectroscopy for chemical analysis (ESCA). NIH/3T3 fibroblast and bovine aortic endothelial cell were cultured on control and PLGA/PMEH surfaces for the evaluation of ceil attachment and proliferation in terms of surface functionality such as the concentration of phosphoryl-choline. Also, the behavior of platelet adhesion on PLGA/PMEH was observed in terms of the surface functionality. The contact angles on control and PLGA/PMEH surfaces decreased with increasing PMEH content from 75$^{\circ}$ to about 43$^{\circ}$. It was observed from the FTIR-ATR spectra that phosphorylcholine groups are gradually increased with increasing blended amount of MPC. The experimental P percent values from ESCA analysis were more 3.28∼7.4 times than that of the theoretical P percent for each blend films. These results clearly indicated that the MPC units were concentrated on the surface of PLGA/PMEH blend. The control and PLGA/PMEH films with 0.5 to 10.0 wt% concentration of PMEH were used to evaluate cell adhesion and growth in terms of phosphorylcholine functionality and wettability. Cell adhesion and growth on PLGA/PMEH surfaces were less active than those of control and both cell number decreased with increasing PMEH contents without the effect of surface wettability. It can be explained that the fibronectin adsorption decreased with an increase in the surface density of phosphorylcholine functional group. One can conclude the amount of the protein adsorption and the adhesion number of cells can be controlled and nonspecifically reduced by the introduction with phosphorylcholine group. Morphology of the adhered platelets on the PLGA/PMEH surface showed lower activating than control and the number of adhered platelets on the PLGA/PMEH sample decreased with increasing the phosphorylcholine contents. The amount of fibrinogen adsorbed on the PLGA/PMEH surface demonstrated that the phospholipid polar group played an important role in reducing protein adsorption on the surface. In conclusion, this surface modification technique might be effectively used PLGA film and scaffolds for controlling the adhesion and growth of cell and tissue, furthermore, blood compatibility of the PLGA was improved by blending of the MPC polymer for the application of tissue engineering fields.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권4호
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• pp.292-300
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• 2004

Orbital blowout fractures are common consequence to blunt periorbital trauma. Pure orbital blowout fractures first occur at the weakest point of the orbital wall. Computed tomography(CT) is recognized to be the best imaging technique to evaluate orbital fractures. The extent and location of a blowout fractures in the CT scan were noted to have an effect on the clinical outcome. In the early posttraumatic period, the presence of significant enophthalmos is difficult to detect because of orbital edema. Early surgical intervention may improve the ultimate outcome because open reconstruction becomes more difficult if surgery is delayed. In this study, we evaluated isolated blowout fractures of the orbital floor by region-of-interest measurements from CT scans and their relationship to ophthalmologic findings. Six patients of the medial orbital wall fractures, eleven patients of the inferior orbital wall fractures, nineteen of the medial and the inferior orbital wall fractures confirmed by CT scan, were evaluated. The area of fracture and the volume of the displaced orbital tissue were determined from CT scan using linear measurements. Each of the calculated values for the area and the volume were compared with the degree of the enophthalmos, the diplopia, and the eyeball movement limitation to determine whether there was any significant relationship between them. The fracture area and the volume of the herniated orbital tissue were significantly positively correlated with the enophthalmos and the ocular motility limitation and not correlated with the diplopia. For the enophthalmos of 2mm or greater, the mean fracture area was 3.55{\pm}1.25cm^2$ and the volume of the herniated orbital tissue was $1.74{\pm}0.97cm^3$; for less than 2mm enophthalmos, $1.43{\pm}0.99cm^3$ and $0.52{\pm}0.49cm^3$, respectively. The enophthalmos of 2mm can be expected with $2.92cm^2$ of the fracture area and $1.40cm^3$ of the herniated orbital tissue. In conclusion, the enophthalmos of 2mm or more, which is a frequent indication for surgery. It can be expected when area of fracture is $2.92cm^2$ or more, or the volume of herniated orbital tissue is $1.40cm^3$ or more. And the CT scan using linear measurements has an application in the assessment of patients with blowout fractures and provides useful information in the posttraumatic evaluation of orbital fractures.

• Journal of Dental Anesthesia and Pain Medicine
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• 제20권4호
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• pp.203-212
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• 2020

Background: This research evaluated the numbness produced by lignocaine at an equal or higher concentration than that of 4% articaine through a single point of injection for maxillary third molar surgery. This randomized double-blind study was conducted to compare the anesthetic efficiency of 4% lignocaine with that of 4% articaine in impacted maxillary third molar surgery using a single buccal infiltration alone. Methods: The study participants were 30 healthy patients requiring the bilateral surgical removal of symmetrically-positioned maxillary third molars. Using a split-mouth design, each patient randomly received buccal infiltration of 1.7 ml of 4% lignocaine and 1.7 ml of 4% articaine during two separate appointments. After 15 minutes of anesthetic injection, surgery was performed by the same surgeon using a consistent technique on both sides. Pinprick test pain scores of the buccal and palatal gingiva of the maxillary third molar after 10 minutes and 15 minutes latencies, pain scores during the surgery, the need for supplemental anesthesia, and patients' satisfaction with anesthetic efficiency were recorded. Surgery performed without supplemental anesthesia was categorized as successful. Results: The success rates of 4% lignocaine and 4% articaine (83.34% vs. 86.67%, P = 1.00) were not significantly different. Only 5 cases (4 cases in the articaine group and 1 case in the lignocaine group) reported mild pain and pressure sensation (NRS ≤ 1) on probing at the palatal side after 15 minutes of latency (P = 0.25). The pain scores of maxillary third molar surgery in the two groups were not significantly different (P > 0.05). Moreover, the statistical analysis confirmed the comparable patient satisfaction of two study groups (P = 0.284). Conclusion: This study provides evidence that single buccal infiltrations of 4% lignocaine and 4% articaine have comparable anesthetic efficacy and success rates for impacted maxillary third molar surgery. Both 4% lignocaine and 4% articaine can produce effective palatal anesthesia and pain control using buccal infiltration alone after 15 minutes of latency.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권4호
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• pp.219-225
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• 2003

Purpose: Platelet Rich Plasma(PRP) application is increasing with sinus inlay bone graft, but there is few research with radiographic ananlysis on effect of PRP in maxillary sinus. The author investigated the amount of bony changes of maxillary sinus for dental implantation among the patients with maxillary inlay graft. Materials and Methods: With 10 patients who were treated with sinus inlay autologous bone grafting combined with PRP technique, and with 5 patients who were treated with sinus inlay grafting only without PRP, the panoramic radiographys which were taken at preoperation, immediate postoperation, 3months postoperation, and 4 months postoperation(a month after dental implantation)periods were analysed. The films had been scanned, and then proceeded throughout image analysis system. The bone density of maxillary grafted sites was compared with adjacent tooth enamel density and remeasured according to density luminosity of each film. The density changes on PRP group and bone graft only group were analysed with non-parameteric statistics method. Results: In PRP combined patients group, bone density on postoperation periods was increased totally. The remarkable enhanced change of bone density was observed on 3 months postoperation period, thereafter the increasing rate was slightly reduced. In only bone graft patients group, bone density on postoperation periods was also increased compared with preoperation period, but the bone density of 4 months postoperation period was decreased compared with 3 months postoperation period. The amount of bone density on PRP group was significantly changed according to periods in contrast to bone graft only group. Conclusion: The bone density on PRP group was remarkably increased at 3 months postoperation compared to bone graft only group and it was seemed to be associated with more new bone formation, less grafted bone resorption at bone grafted sites with PRP.

• 대한장애인치과학회지
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• 제8권2호
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• pp.118-121
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• 2012

본 증례는 Down 증후군 및 선천성 심장 질환을 갖는 여자 환자에서 전위되어 매복된 상악 견치에 대한 교정 치료 내용이다. 매복된 치아의 맹출 공간이 부족하여 고정식 교정 장치를 이용하여 치아 공간을 확보한 후 교정적인 견인을 통하여 매복 치아를 전위된 위치로 배열하였다. 심내막염 방지를 위하여 교정 치료 중 필요 시 미국심장협회의 가이드라인에 따라 예방적 항생제를 복용하였고 합병증 없이 교정 치료를 마무리하였다.