상악동의 염증성 병변 진단 시 Waters 방사선영상의 진단능 평가

학위논문 (석사)-- 서울대학교 대학원 : 치의학과, 2012. 2. 최순철.1. 목 적 상악동 내의 염증성 병변 진단 시 Waters 방사선영상의 진단능을 평가하고 점막비후의 두께와 위치에 따른 진단능을 알아보며 판독자의 경험이 진단능에 미치는 영향을 평가하고자 하였다. 2. 방 법 본 연구는 CT 영상과 Waters 방사선영상을 모두 촬영한 106명의 환자에서 189개의 상악동을 대상으로 시행하였다. CT 영상에서 점막비후 등의 염증성 변화를 보이는 상악동과 보이지 않는 상악동을 분류하였다. CT 영상에서 상악동 벽의 점막비후 두께에 따라 5군으로 분류하였는데 상악동 벽의 점막비후가 없는 경우, 점막비후가 1~5 mm인 경우, 점막비후가 6~10 mm인 경우, 점막비후가 11 mm 이상인 경우, 점막비후가 상악동을 모두 채운 경우로 분류하였다. 또한 상악동에서 점막비후를 보이는 위치에 따라 7군으로 분류하였는데 대부분이 두 벽 이상에서 점막비후를 보이므로 중복으로 포함시켰다. 전벽, 후벽, 내벽, 외벽, 상벽, 상악동저, 모든 벽에서 점막비후가 보이는 경우로 분류하였다. Waters 방사선영상의 진단능을 평가하기 위하여 판독자는 서울대학교 치의학대학원 4학년 학생과 구강악안면방사선학 전공자의 두 그룹으로 나누었다. 각 그룹 당 3명의 판독자가 환자에 대한 사전 지식 없이 5단계 체계로 일주일 간격으로 2회씩 Waters 방사선영상에서 병소의 유무를 ROC분석을 통하여 평가하였다. 각 판독자의 판독결과를 t-test로 비교하였으며 점막비후 두께와 위치에 따른 진단능의 차이와 점막비후의 위치에 따른 진단능의 차이를 알아보기 위하여 ANOVA를 이용하였다. 두 그룹의 판독자간 일치도와 판독자내 일치도를 kappa value를 구하여 평가하였다. 3. 결 과 전공자 그룹(0.817)이 학생 그룹(0.701)에 비해 전체적으로 진단능이 높게 나타났다(p<0.05). 그룹 내 판독자간 일치도는 전반적으로 전공자 그룹(0.653)이 학생 그룹(0.335)에 비해 높게 나타났고, 판독자내 일치도도 전공자 그룹(모두 0.7이상)에서 학생 그룹(3명 중 2명이 0.4 이상)에 비해 높은 일치도를 보였다. 점막비후 두께에 따른 진단능은 전공자 그룹과 학생 그룹 모두 점막비후 두께가 증가함에 따라 진단능이 증가하였으나 방사선불투과상이 전체를 채운 경우는 진단능이 감소하였다 (p<0.05). 점막비후 위치에 따른 진단능은 전공자 그룹과 학생 그룹 모두 후벽에 점막비후가 있을 때 가장 높게 나타났으나 학생 그룹에서는 유의성을 보이지 않았다(p>0.05). 4. 결 론 Waters 방사선영상은 상악동의 염증성 병변 검사에 좋은 진단능을 보이며 점막비후의 두께가 증가할수록 진단이 용이하나 많은 판독 경험이 필요하다. 그러므로 경험이 부족한 판독자의 경우 Waters 방사선영상에서 병변이 의심될 때는 추가적인 검사가 필요하다.1. Purpose The aim of this study was to evaluate the diagnostic ability of Waters radiograph in the diagnosis of inflammatory changes in the maxillary sinus and the effect of observers experience on their diagnostic performance. 2. Material and methods The study was performed on 189 maxillary sinuses observed with Waters radiographs and CT. Maxillary sinuses monitored by CT were divided into 5 groups based on the degree of mucosal thickening, including 115 cases with no mucosal thickening, 29 cases with thickening of 1~5 mm, 16 cases with thickening of 6~10 mm, 12 cases with thickening of more than 11 mm, and 17 cases of total radiopacity. Also, maxillary sinuses were categorized into 7 groups according to the location of mucosal thickening. Because most sinuses had mucosal thickening on more than two walls, groups of sinuses were overlapping. The results were comprised of 38 cases with mucosal thickening on the anterior wall, 33 cases with thickening on the posterior wall, 37 cases with thickening on the medial wall, 45 cases with thickening on the lateral wall, 30 cases with thickening on the superior wall, 50 cases with thickening on inferior wall, and 28 cases with thickening on all walls. These CT results were used as the gold standard. Three oral maxillofacial radiologists and three dental students participated in this study. Each observer made a diagnosis based on the Waters radiographs twice at an interval of one week blinded. The presence or absence of antral mucosal thickening was scored using 5-grade scale system. ROC analysis with calculation of the area under the ROC curve was performed. Inter/intra-observer agreement was calculated using a kappa value. 3. Results The diagnostic ability of the oral maxillofacial radiologist group was significantly superior to that of the dental student group (p<0.05). Inter/intra-observer agreement of the oral maxillofacial radiologist group was also higher than in the student group. The diagnostic ability of the oral maxillofacial radiologist and dental student groups improved as the thickness of mucosal thickening increased (p>0.05). However, their diagnostic ability was decreased in cases of total radiopacity (p>0.05). The diagnostic ability of the two groups was highest in sinuses with mucosal thickening on the posterior wall. Statistical differences were not observed in student group (p>0.05). 4. Conclusion The Watersradiograph alone allows facile diagnosis of inflammatory changes in maxillary sinus, especially when mucosal thickening is increased. In addition, sufficient observer experience is warranted since the diagnostic utility of Waters radiographs strongly depends on the skill and knowledge of the observer. Therefore, further examination is recommended when an inflammatory lesion is suspected from Waters radiographs.Maste

돼지 심막에서 추출한 새로운 콜라겐 차폐막의 임상적 효율에 대한 무작위, 이중 맹검 임상 비교 연구

학위논문 (박사)-- 서울대학교 대학원 : 치의학대학원 치의과학과, 2018. 8. 김성태.Purpose : The aim of this study was to radiographically and clinically compare dimensional alterations during ridge preservation using two extracellular matrix (ECM) membranes. Methods : A widely used ECM membrane (Bio-Gide®) and newly developed ECM membrane (Lyso-Gide®) were applied during the ridge preservation procedure in control and test groups, respectively. Cone-beam computed tomography (CBCT) scans were taken at surgery day and 6 months after the ridge preservation procedure. Alginate impressions were obtained at 1 week and 6 months after the ridge preservation procedure. Results were statistically analyzed using the independent t-test and the nonparametric Whitney U test. Results : Change of extraction socket dimension from master casts showed no significant difference between two ECM membranes. Likewise, differences of width, height and quantity of bone tissue from CBCT scans showed no significant difference. The mean VAS of characteristics of test group was shown higher than that of control group. Conclusions : Newly developed ECM membrane in ridge preservation procedure showed comparable clinical/ radiographical result to widely used ECM membrane. 1. Introduction . 1 2. Material & Methods . 6 3. Results . 12 4. Discussion 14 5. References 19 6. Tables . 24 7. Figures . 27 국문초록 33Docto

Preparation of silica based core/shell nanostructures for bioimaging and drug delivery

학위논문 (석사)-- 서울대학교 대학원 : 나노융합학과, 2012. 2. 박원철.In recent years, the development of nanostructured materials for biomedical applications has been continued by many researchers. Various nanomaterials have been studied as promising candidates and among them, silica based core/shell nanostructured materials were conducted to study actively due to their low toxicity, easy modification, inexpensive process, etc. In this research, we synthesized two types of silica based core/shell nanostructured materials. First, RITC-doped core/mesoporous shell silica nanostructured materials were synthesized for investigating the possibility to act as theranostic nanocarriers. RITC-encapsulated core silica nanoparticles were prepared by sol-gel process. The cores were further grown to various size by coating with pure silica through the Stöber method. Furthermore, mesoporous shells were coated again by using cetyl trimethylammonium bromide (CTAB) as porous guiding agent. The shape, size, and fluorescence of the as-prepared nanostructured materials were confirmed by using transmission electron microscopy (TEM), dynamic laser scattering (DLS), and photoluminescence (PL) spectroscopy. Ibuprofen loading and release experiments in buffer solution (pH 7.4) showed that these nanostructured materials were available for drug delivery system. In addition, cytotoxicity test and fluorescent imaging were carefully conducted to investigate the cell-level behavior of the nanostructured materials. From these results, we demonstrated that the as-synthesized nanostructured materials had the potential applicability as theranostic nanocarriers. Second, iron oxide core/RITC-doped silica shell nanostructured materials were prepared. The as-prepared nanostructured materials were suitable for dual imaging. The synthesis of the nanostructured materials was based on reverse micelle method and iron oxide nanocrystals coat with RITC-doped silica. The as-prepared nanostructured materials were analyzed to confirm the shape, size, and distribution by TEM and DLS. In addition, fluorescent properties were discussed through the analysis of PL. By WST-1 assay, we confirmed that the as-prepared nanostructured materials showed low toxicity to cells. Finally, through in vivo and in vitro MR and fluorescent imaging, we verified that the as-prepared nanostructured materials could be used as dual imaging contrast agents. The as-prepared nanostructured materials were intended to improve the diagnostic accuracy and broaden the diagnostic scope of diseases by performing both MR and fluorescence imaging.Maste