• Journal of Korean Dental Science
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• 제16권1호
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• pp.23-34
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• 2023

Purpose: This study aims to investigate the force delivery profile of thermoformed aligners (TFA) compared with direct-printed aligners (DPA) and to explore the effect of different activation amounts on forces and moments of respective groups. A secondary objective is to observe the amount of stress relaxation that occurs over the 7~14 days when aligners are maintained in a simulated intraoral environment. Materials and Methods: An in vitro setup was created to quantify forces and moments. It consisted of a three dimensional-printed base plate and segmented maxillary teeth, placed in a semi-enclosed chamber to maintain a temperature of 37℃. Ninety clear aligners were divided into nine groups of ten aligners each based on material types (Zendura, ATMOS, TC-85) and activation amounts. Aligners were created with 0.00, 0.25- and 0.50-mm activations for lingual bodily movement of the upper left central incisor and kept on models in the "stressed" position in a 37℃ water bath. Three force components acting on the upper left lateral incisor, upper left central incisor, and upper right central incisor were measured for each time point, beginning from the initial baseline measurement, 8 hours, 16 hours, 24 hours, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, and lastly, 14 days. Result: TC-85 aligners in every activation group showed less force on teeth than Zendura and ATMOS. Significant force levels from 0.0 mm activation were present and stayed consistent over the course of 14 days. Comparisons made for baseline measurements to 7-days and 14-days showed statistically significant change from the baseline force level. Conclusion: TC-85 aligners demonstrated lower, more consistent forces with fewer side effects. Aligners can generate forces even when no activation is programmed. No major decreases in force levels over time were observed; the intra-oral clinical simulated environment and length of observation time could contribute to this.

• Journal of Microbiology and Biotechnology
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• 제33권1호
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• pp.35-42
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• 2023

This study aimed to identify the therapeutic ability of a novel toll-like receptor (TLR) 5 agonist, KMRC011, on ulcerative colitis induced by Citrobacter rodentium and dextran sulfate sodium in a C57BL/6N mouse model. Ulcerative colitis was induced in the mice by the oral administration of 1% dextran sulfate sodium in sterile drinking water for seven days ad libitum, followed by C. rodentium infection on the seventh day by intra-gastric administration (DSS-CT group). KMRC011 was administered intramuscularly at both 24 h and 15 min before (Treatment 1 group), and at both 15 min and 24 h after (Treatment 2 group) the C. rodentium infection. The length of the large intestine and histopathological counts were significantly greater and mucosal thickness was significantly thinner in the Treatment 1 group compared to the DSS-CT and Treatment 2 groups. Il-6 and Il-10 mRNA expression levels were upregulated, while Ifn-γ and Tnf-α mRNA expression levels were significantly downregulated in the Treatment 1 group, compared to the DSS-CT group. NF-κB p65 expression level was elevated due to ulcerative colitis in the DSS-CT group, but was significantly downregulated in the Treatment 1 group. Overall, KMRC011 showed protective effects against murine colitis by inhibiting NF-κB signaling.

• Journal of Dental Anesthesia and Pain Medicine
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• 제24권1호
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• pp.57-65
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• 2024

Background: The objective of behavioral guidance is to establish effective communication that aligns with a child's requirements to manage disruptive behavior. This study aimed to evaluate the effectiveness of the Tell-Show-Do and Ask-Tell-Ask techniques in managing dental anxiety in children during their initial appointment. Methods: The study included 50 children (28 boys and 22 girls) without any prior experience between the ages of 7 and 11 at their first dental visit. The children were randomly categorized into two groups: Group 1, Tell Shows Do, and Group 2, Ask-Tell-Ask. Subsequently, all children underwent noninvasive treatment procedures such as restorations, sealants, and oral prophylaxis. Furthermore, behavioral management techniques were employed based on the allocated group. Finally, anxiety levels for all children were assessed using the Raghavendra, Madhuri, and Sujata Pictorial Scale (RMS-PS) and heart rate at three different intervals (before, during, and after). The obtained data were entered into Microsoft Excel, and statistical analysis was performed using SPSS software. A paired t-test and Mann-Whitney U-test were used to compare the mean and median values of the two groups and determine their effectiveness. Results: Children in the TSD group exhibited statistically significant heart rates and RMS-PS scores in intra-group comparisons. However, children in the ask-tell-ask group showed a significant reduction only in the RMS-PS scores (P < 0.001) but not in the measures used to assess heart rate (P < 0.001). Conclusion: Tell-Show-Do was more effective than ask-tell-ask in alleviating dental anxiety in children. The simultaneous application of these two strategies can synergistically alleviate dental anxiety during a child's initial dentist appointment.

• IMMUNE NETWORK
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• 제14권1호
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• pp.45-53
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• 2014

Osteoarthritis (OA) is a degenerative joint disease characterized by a progressive loss of cartilage. And, increased oxidative stress plays a relevant role in the pathogenesis of OA. Ursodeoxycholic acid (UDCA) is a used drug for liver diseases known for its free radical-scavenging property. The objectives of this study were to investigate the in vivo effects of UDCA on pain severity and cartilage degeneration using an experimental OA model and to explore its mode of actions. OA was induced in rats by intra-articular injection of monosodium iodoacetate (MIA) to the knee. Oral administration UDCA was initiated on the day of MIA injection. Limb nociception was assessed by measuring the paw withdrawal latency and threshold. Samples were analyzed macroscopically and histologically. Immunohistochemistry was used to investigate the expression of interleukin-$1{\beta}$ (IL-$1{\beta}$), IL-6, nitrotyrosine and inducible nitric oxide synthase (iNOS) in knee joints. UDCA showed an antinociceptive property and attenuated cartilage degeneration. OA rats given oral UDCA significantly exhibited a decreased number of osteoclasts in subchondral bone legion compared with the vehicle-treated OA group. UDCA reduced the expression of IL-$1{\beta}$, IL-6, nitrotyrosine and iNOS in articular cartilage. UDCA treatment significantly attenuated the mRNA expression of matrix metalloproteinase-3 (MMP-3), -13, and ADAMTS5 in IL-$1{\beta}$-stimulated human OA chondrocytes. These results show the inhibitory effects of UDCA on pain production and cartilage degeneration in experimentally induced OA. The chondroprotective properties of UDCA were achieved by suppressing oxidative damage and inhibiting catabolic factors that are implicated in the pathogenesis of cartilage damage in OA.

• 한국치위생학회지
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• 제4권2호
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• pp.277-291
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• 2004

The purpose of this study is to analyze the dental hygienists' overall performance in operative restoration and the clinical performance in operative restoration according to dental hygienists' career and to provide basic data for establishing the appropriate range of dental hygienists' work. Subjects of this study are 339 dental hygienists working at dental clinic and hospital nationwide, selected by their working place, career, type of clinic, and location of clinical institution. The distribution of people who responded to the survey shows that 81 belong to beginner level(less than 2 years since entering clinic), 115 intermediate level(2 to 3 years since entering clinic), 81 higher level(4 to 5 years since entering clinic) and 62 advanced level(more than 6 years since their entering clinic). In terms of the types of clinical institution, 178 belong to dental clinics and 161 belong to dental hospitals. The survey used in this study are focused on perception about clinical performance in operative dentistry and adequacy of the work. Operative dentistry consists of operative restoration and endodontic therapy. The operative restoration consists of 15 categories such as patient welcoming, examination and diagnosis, planning of treatment, anesthesia, control of moisture, cavity preparation, pulp protection, matrix band application, amalgam filling, resin filling, glass ionomer cement filling, abrasive strip removal, rubber dam removal, bite check and polishing, patient education, and arrangement. The reliability was Cronbach's Alpha .9453. SPSS 10.0 for Windows was used to analyze the responses. One way ANOVA was utilized to verify the differences in the dental hygienists' job performance in operative restoration and their job performance according to career. When significant difference was found. Duncan multi comparison post hoc was done. To sum up the results of this study, patient welcoming look the first place in the operative restoration. It was followed by patient education, examination and diagnosis, introducing treatment plan, resin filling, glass ionomer cement filling, amalgam filling, bite check and polishing, anesthesia, pulp protection, control of moisture, abrasive strip removal, cavity preparation, matrix band application, rubber dam removal, and anesthesia. In terms of the clinical performance by career, there were significant differences in 19 activities such as medical eraluation, oral examination, patient charting, intra oral readio graphs, firm developing fixing mounting, curing light gun, education of attention content after operation. Based on the results of this study, the specific range of operative restoration for dental hygienists should be focused on providing basic data for dentists' diagnosis, alleviation of fear and aching accompanied by injection and anesthesia, data providing for dentists' decision of anesthesia degree, and maximization of control of moisture.

• Journal of Chest Surgery
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• 제38권9호
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• pp.595-600
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• 2005

배경: 콜키신(Colchicine)은 면역 억제 작용을 갖고 있어 자가 면역 질환인 통풍(Gout)등의 질환의 치료제로 이용되어 왔다. 본 연구는 콜키신을 동종이형의 심장이식된 백서에 투여하여 면역억제효과를 확인하고자 하였다. 대상 및 방법: 백서에서의 동종이형 심장이식 거부 반응에 대하여 면역억제제를 투여하지 않는 대조군(Control group)(n=6)과 사이클로스포린(Cyclosporin A) 투여군(n=20), 콜키신 변형물질 투여군(n=20)을 비교함으로써 콜키신의 면역 억제 효과를 비교 검토하였다. 결과: 면역억제제를 투여하지 않은 대조군(n=6)에서는 모두 3주 이내에 거부반응을 보였고, 사이클로스포린(Cyclosporin A) 투여군(n=20)에서는 감염으로 추정되는 한 마리가 술 후 18일째 죽었고, 나머지 19마리는 100일 이상 생존하였다. 또한 콜키신 변형물질 투여군(n=20)에서도 술 후 9일 째에 마취 문제로 인한 호흡부전으로 한 마리가 사망한 외에 나머지는 100일 이상 생존하였다. 결론:본 실험에서는 백서에서의 동종이형 심장 이식 후 현재 면역억제제로 널리 사용되고 있는 Cyclosporin A 투여군과 콜키신 변형물질 투여군을 비교하여 본 바 콜키신 변형 물질 투여군에서도 Cyclosporin A 투여군과 마찬가지로 장기 생존의 결과를 얻을 수 있어 면역 억제 효과가 있음을 알 수 있었다.

• 대한소아치과학회지
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• 제32권1호
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• pp.49-54
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• 2005

Shell teeth는 매우 드문 상아질 이상으로 상아질 이형성증의 한 형태로서 특징적으로 정상적인 법랑질, 매우 얇은 상아질, 비정상적으로 큰 치수강, 짧아진 치근 등을 보인다. Shell teeth는 1954년 Rushton이 21세 남자 환자에서 나타난 증상을 설명하여 처음 명명하였으며, 1984년 Kinirons이 8세 남아의 shell teeth에 대해 보고하였다. 1992년 Harrison과 Kennedy는 7세 6개월 된 남아에서 보인 shell teeth를 14년간 관찰하여 보고하였는데 이 환아는 유치열과 영구치열 모두 shell teeth가 관찰되었고, 일반적인 shell teeth와 달리 치관에서는 shell teeth의 특징이 나타나지 않았으며, 치근에서만 나타났다. 매우 얇은 상아질과 큰 치수강은 국소적 이형성증에도 관찰되는 특징인데, shell teeth는 전치열에서 보이는데 반해 국소적 이형성증은 한정된 몇 개의 치아에서만 관찰되어 감별진단 할 수 있다. 본 증례는 3세 남아에 관한 것으로 구강내 소견은 모든 유치 치관이 파괴되어 상아질이 노출되어 있었고, 방사선 소견은 얇은 상아질로 둘러싸인 매우 큰 치수강과 확장된 치근관을 보였으며 다수의 소구치가 결손되어 있었다. 환아는 행동조절의 문제 때문에 전신마취하에 치료를 받았다. 현재 환아는 공간유지장치를 장착하고 있으며, 정기적인 관찰이 필요하리라 사료된다.

• 약학회지
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• 제37권5호
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• pp.511-519
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• 1993

The short and variabke transit of drug throught GI tracj and the inter-and intra-subject variations of the transit restrict the sustained drug absorption after oral adminstration. These restrictions may be solved by retaining the dosage forms in the stomach. Then the dosage form will act as a platform which releases the drug slowly and makes the GI absorption occur for a long time. In this study, as the platforms, PVP hydrogels were synthesized by chemical and y-irradiation method in the cylindrical test tube. The chemical method means the synthesis of the hydrogel by heating the mixed solution of N-vinyl-2-pyrrolidone [monomer], acrylated albumin [crosslinking agent], 2, 2'-agobis(2-methylpropionitrile) [initiator] and proxyphylline [drug] at $65^{\circ}C$ for 5 hr. The $\gamma$-irradiation method means the synthesis of the hydrogel by irradiation with $^{60}$ Co $\gamma$-ray of the mixed solution of the monomer, acrylated albumin, and flurbiprofen [drug] at room temperature with total 0.2 Mrad for 3 hr. Our intention is to design the hydrogel tablet (diameter : 1.20 cm, thickness : 0.60 cm) which swells in the gastric fluid after oral administration to such a size that passing through the pylorus could be inhibited during the period of drug release. After releasing drug, the hydrogel should be degraded by the enzymeatic digestion in the stomach, or by hydrolysis and eventually solubilized. Thus, in votro tests were performed to examine the factors that affect swelling and drug release from the PVP hydrogels. Experimental results show that the hydrogels swell to a size larger than the diameter of the pylorus(l.3$\pm$0.7 cm) and the hydrogel prepared by the chemical method is digested by pepsin. But the hydrogel prepared by the $\gamma$-irradiation method was not digested by the pepsin and just collapsed with time. Thus, the swelling of the hydrogel synthesized by $\gamma$-irradiation was independent albumin acrylation time and pepsin concentration. But drug content and radiation dose affected the swelling and drug release kinetics of the hydrogel. Drug release from the hydrigels was prolonged up to about 24 hr. Therefore, it was concluded that by adjusting these factors, the albumin-crosslinked PVP hydrogel synthesized by $\gamma$-irradiation method is expected to be retained in the stomach for up to 60hr and be a potential platform of drugs for long-term GI absorption.

• Journal of Pharmaceutical Investigation
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• 제31권4호
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• pp.265-271
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• 2001

In order to elucidate the influence of intestinal and hepatic first-pass effect on the pharmacokinetics of triflusal, the biotransformation of triflusal in the gastrointestinal tract and liver was designed. Moreover, we tried to establish an HPLC method applicable for bioassay and available to pharmacokinetics, not only with the simultaneous determination of triflusal and its active metabolite, 2-hydroxy-4-trifluoromethyl benzoic acid (HTB), but also with improving sensitivity. After the administration of triflusal (10 mg/kg) and HTB (10 mg/kg) into femoral vein, portal vein (only triflusal) and oral route (only triflusal), pharmacokinetic parameters were investigated from the plasma concentration-time profiles of triflusal and HTB in rats. An HPLC method was developed for the simultaneous determination of triflusal and HTB in rat plasma, urine and bile. The HPLC analysis was carried out using a C18 column and acetonitrile-methanol-water (25:10:65, v/v/v) as the mobile phase and UV detection at 234 nm. Furosemide was used as the internal standard. The calibration curves were linear over the concentration range $0.05-5.0\;{\mu}g/ml$ for triflusal and $0.2-200.0\;{\mu}g/ml$ for HTB with correlation coefficients greater than 0.999 and with intra-day or inter-day coefficients of variation not exceeding 10.0%. This assay procedure was applied to the study of metabolite pharmacokinetics of triflusal and HTB in rats. It was supposed that triflusal was almost metabolized in vivo because urinary and biliary excreted amounts of triflusal could be ignored as it was lower than 1.2% of the administered dose. According to the gastrointestinal and hepatic biotransformation pathways of triflusal, it was found that triflusal was hydrolyzed by about 5% in intestine and metabolized by about 53% in liver, and that the bioavailability of triflusal after oral administration of triflusal was 0.44, and also that the fraction of total elimination rate of triflusal which formed HTB in liver $(F_{mi},\;%)$ was about 98%. These results showed that triflusal was almost metabolized in liver, and the total elimination of triflusal in the body was dependent to the formation rate of HTB from triflusal in liver.

• 대한치과보철학회지
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• 제55권1호
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• pp.61-70
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• 2017

본 증례에서는 기존의 총의치 사용 환자에서 의치의 이장된 인상면을 스캔하고 이를 삼차원적으로 반전하여 잔존 치조제의 형태를 재현하고, 의치에 방사선 불투과성 마커를 부착한 상태로 스캔 및 CT 촬영을 진행하여 스캔 이미지와 CT 영상이 중첩된 데이터 상에서 임플란트 식립을 계획하였다. 수술 당일에는 치은 형태에 맞게 제작된 맞춤형 지대주와 임시 수복물을 장착하였다. 임플란트 고정체의 골유착이 완료된 이후 최종 보철물을 제작하는 과정에서는 임플란트 식립 전 미리 스캔하여 저장된 임플란트 지대주 이미지 파일과 구강 내 지대주 상태에서 채득된 구강 스캔 이미지를 중첩하였다. 중첩을 통해 얻어진 정확한 지대주 형태 상에서 최종 보철물을 제작함으로써 최종 보철물의 변연 적합도를 높이고 임상 과정을 간소화 할 수 있었다.