• Title/Summary/Keyword: 두부촬영

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Facial soft tissue measuring analysis of normal occlusion using three-dimensional CT imaging (3차원 CT 영상을 이용한 정상교합자의 안면 연조직 계측 분석)

  • Han, Soo-Yeon;Baik, Hyoung-Seon;Kim, Kee-Deog;Yu, Hyung-Seog
    • The korean journal of orthodontics
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    • v.35 no.6 s.113
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    • pp.409-419
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    • 2005
  • Studies for diagnostic analysis using three-dimensional (3D) CT images are recently in progress and needs for 3D craniofacial analysis are increasing in the fields of orthodontics. It is especially essential to analyze the facial soft tissue after orthodontic treatment and orthognathic surgery. In this study 3D CT images of adults with normal occlusion were taken to analyze the facial soft tissue. Norms were obtained from CT images of adults with normal occlusion (12 males, 11 females) using a computer program named V works 4.0 program. 3D coordinate planes were established using soft tissue Nasion as the reference point and a total of 20 reproducible landmarks of facial soft tissue were obtained using the multiple reconstructive sectional images (axial, sagittal and coronal images) of the V works 4.0 program: soft tissue Nasion, Pronasale, Subnasale, Upper lip center, Lower lip center, soft tissue B, soft tissue Pogonion, soft tissue Menton, Endocanthion (Rt/Lt), Alare lateralis (Rt/Lt), Cheilion (Rt/Lt), soft tissue Gonion (Rt/Lt), Tragus (Rt/Lt), and Zygomatic point (Rt/Lt). According to the established landmarks and measuring method, the 3D CT images of adults with normal occlusion were measured and the normal positional measurements and their Net (${\delta}=\sqrt{{X^2}+{Y^2}+{Z^2}}$) values were obtained using V surgery program, In the linear measurement between landmarks, there was a significant difference between males and females except Na' -Sn and En(Rt)-En(Lt). The normal ranges of Na'-Zy, Na'-Ch and Na'-Go' (facial depth) were obtained, which was difficult to measure by two-dimensional (2D) cephalometric analysis and facial photographs. These data may be used as references for 3D diagnosis and treatment planning for patients with malocclusion and dentofacial deformity.

A study on the smile of Korean Youth compared with twenty years ago (20년전과 비교한 한국청년의 미소 변화에 관한 연구)

  • Beom, Seung-Gyun;Jung, Ji-Hye;Kim, Tae-Young;Lee, Kyung-Eun;Dong, Jin-Keun
    • The Journal of Korean Academy of Prosthodontics
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    • v.50 no.3
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    • pp.162-168
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    • 2012
  • Purpose: Teeth are generally exposed when people smiling. Moreover, the exposed teeth and soft tissue when smiling becomes an important guideline for esthetically prosthetic restoration. This research is to compare and find out differences of Korean young men's smile living in presence and twenty years ago. Materials and methods: Subjects, 100 young men (50 male and 50 female), were required about several aspects; normally developed physical condition, no psychological or genetic disorders, a fine face with no loss of teeth, no experience in orthodontic or prosthetic treatment, relatively normal occlusion, aged between 20-29. The photos of the subject at rest position and front face when fully smiled were taken three times. 100 photos (50 male and 50 female) were chosen at random from the 240 university students' smile photos taken by Yoon and his colleagues in 1991. By Hulsey's method of measuring smile, several factors; the change of upper lip curvature, the change of the relation between the upper lip and teeth, parallelism between Mx. incisor and lower lip, contact relation between Mx. incisor and lower lip and teeth displayed in a smile, were measured and analyzed. Meanwhile, ten dentists assessed aesthetic evaluation about men and women's smile for twice and recorded and compared smile score. The -test (P<.05) was used to compare the measured value. The difference of smile score was analyzed by t-test (P<.05). Results: The smile score calculated in 2011 (60.22) was higher than that of 1991 (52.80). Among five measurement categories, the noticeable difference was distinguished from two factors; the change of upper lip curvature and contact relation between Mx. incisor and lower lip. Conclusion: The Korean young men's smile has been considerably improved for twenty years. And it is found that the change of upper lip curvature plays an important role, that is, the smile formed with an ascended labial commissure has been increased significantly.

The Three Dimensional Analysis on Nasal Airway Morphology in Class III Malocclusion (골격성 III급 부정교합자의 Nasal Airway 형태에 관한 3차원적 분석 연구)

  • Kim, Moon-Hwan;Lee, Jin-Woo;Cha, Kyung-Suk;Chung, Dong-Hwa
    • Journal of Dental Rehabilitation and Applied Science
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    • v.24 no.4
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    • pp.389-403
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    • 2008
  • In Angle's Class III malocclusion, which has higher incidence in Korean than Western, depressed midfacial profile with protruded lower lips and mandible may give rise to many functional, esthetic, psychological, social problems. Due to the different malocclusion incidence according to racial differences, many previous studies focused on the relationship between Class II malocclusion and nasal airway obstruction. Previous studies used lateral cephalography which has limitations of 2 dimensional image with projection error and identification error. Therefore, the purpose of this study was to analyze morphologic differences in the nasal airway between normal occlusion and Angle's Class III malocclusion patients using 3-dimensional facial computed tomography. Thirteen normal occlusion(7 men and 6 women) and sixteen skeletal Class III(7 men and 9 women) patients were selected and 3-dimensional facial computed tomography taking was performed. Comparison between two group in volume and sectional area of nasal airway were carried out. The results were followed. 1. In the comparison of absolute nasal airway volume, oropharyngeal space of experimental group were larger than control group but there are no significant difference in other. 2. In the comparison of relative nasal airway volume, oropharyngeal space of experimental group were larger than control group but there are no significant difference in other. 3. In the oropharyngeal space width on frontal and lateral view, the similar tendency was revealed between two groups. 4. In the lateral curvature of nasal airway, the similar tendency was revealed between two groups.

Etiology and Analysis of Severity in Childhood Pancreatitis (소아 췌장염의 원인과 중증도 분석)

  • Park, Jun-Eun;Kim, Kyong-Mo
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.2 no.2
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    • pp.194-203
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    • 1999
  • Purpose: Childhood pancreatitis has more various and somewhat different etiology than adult. Until now the analysis of severity in childhood pancreatitis were not well-known, although several studies have been made. Therefore, we studied the etiology and complications in childhood pancreatitis and analyzed whether Ranson and CT criteria could be applicated to evaluate the severity of childhood pancreatitis patients. Methods: The records of 30 patients with pancreatitis under 15 years of ages who were diagnosed in Asan medical center were reviewed. Age, sex, history, etiology, clinical features and treatment was reviewed in all patients but complications, Ranson and CT criteria were available in only 12 patients. Correlation between the number of complications and both Ranson and CT criteria were calculated with Spearman correlation coefficient. Results: 1. Median age at diagnosis was 7.3 years of age. 28 cases were acute pancreatitis and 2 cases were chronic pancreatitis. 2. Etiology: choledochal cyst(8 cases), drug (7 cases), trauma (4 cases), infection (3 cases), biliary stone or bile sludge (3 cases), idiopathic (2 cases) Hemolytic uremic syndrome, pancreatic duct obstruction, iatrogenic (1 case). 3. Local complications were ascites (5 cases), pseudocyts (4 cases) and systemic complications were hyperglycemia (4 cases), hypocalcemia (3 cases), pleural effusion (3 cases), etc. 4. Positive correlation was found between the number of complication and Ranson creteria (r=0.78, P=0.0016) and between the number of complication and CT criteria (r=0.65, P=0.015) in 13 cases. Conclusion: A trial to search the biliary duct anomaly may help to find the causes of childhood idiopathic pancreatitis, and both Ranson and CT criteria can be applicated to pediatric patients to evaluate the severity of childhood pancreatitis.

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Development of a Model for MR-CT Bi-directional Conversion based on scCycleGAN (scCycleGAN 기반 MR-CT 상호 변환 모델의 구축)

  • Da-Um Jeong;Seung-Jin Park;Seung-Yeon Shin;Yong-Ah Lee;Seong-Bin Jang;Jong-Cheon Lim;Joo-Wan Hong;Dong-Kyoon Han
    • Journal of the Korean Society of Radiology
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    • v.18 no.6
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    • pp.715-724
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    • 2024
  • We aimed to build an MR-CT interconversion model based on structure-constraints Cycle-constraints Generative Adversarial Neural Networks (scCycleGANs). We used MDCT (Somatom Definition Flash CT, SIEMENS, Germany) and 3.0T MRI (Ingenia 3.0T CX MRI, PHILIPS, Netherlands) as our hardware equipment and Python (3.12.6) and PyTorch (2.4.0) as software. The study model was scCycleGAN. We acquired 2,871 and 2,436 brain CT and MR (T2WI) images of 87 patients, respectively, and for a total of 5,307 medical images, CT and MR images taken at the same level were classified through primary evaluation, and 364, 27, and 8 pairs of images were labeled as training, validation, and test data, respectively. Then, we applied hybrid objective function to the GAN model based on the basic APS frameworks to build the model, and the evaluation of the generated model was divided into quantitative and qualitative evaluation. The qualitative evaluation was conducted on 10 radiologists with more than 20 years of experience, and the quantitative evaluation was set as PSNR, IOU, SSIM, and MAE. The results of the qualitative evaluation showed that the percentage of 'positive responses', defined as a response of 'Neutral' or better, was 63% and 96% for the Synthesis CT (sCT) and Synthesis MR (sMR) groups, respectively, while the quantitative evaluation metrics PSNR, SSIM, and MAE achieved the initial target values for both groups. Our study can be used as basic guided research in the field of medical image conversion and synthesis. And further research and complementary studies are expected to solve problems such as model lightweighting to reduce the dose burden on patients and medical costs if applied to clinical environments.

Radiation Therapy Using M3 Wax Bolus in Patients with Malignant Scalp Tumors (악성 두피 종양(Scalp) 환자의 M3 Wax Bolus를 이용한 방사선치료)

  • Kwon, Da Eun;Hwang, Ji Hye;Park, In Seo;Yang, Jun Cheol;Kim, Su Jin;You, Ah Young;Won, Young Jinn;Kwon, Kyung Tae
    • The Journal of Korean Society for Radiation Therapy
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    • v.31 no.1
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    • pp.75-81
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    • 2019
  • Purpose: Helmet type bolus for 3D printer is being manufactured because of the disadvantages of Bolus materials when photon beam is used for the treatment of scalp malignancy. However, PLA, which is a used material, has a higher density than a tissue equivalent material and inconveniences occur when the patient wears PLA. In this study, we try to treat malignant scalp tumors by using M3 wax helmet with 3D printer. Methods and materials: For the modeling of the helmet type M3 wax, the head phantom was photographed by CT, which was acquired with a DICOM file. The part for helmet on the scalp was made with Helmet contour. The M3 Wax helmet was made by dissolving paraffin wax, mixing magnesium oxide and calcium carbonate, solidifying it in a PLA 3D helmet, and then eliminated PLA 3D Helmet of the surface. The treatment plan was based on Intensity-Modulated Radiation Therapy (IMRT) of 10 Portals, and the therapeutic dose was 200 cGy, using Analytical Anisotropic Algorithm (AAA) of Eclipse. Then, the dose was verified by using EBT3 film and Mosfet (Metal Oxide Semiconductor Field Effect Transistor: USA), and the IMRT plan was measured 3 times in 3 parts by reproducing the phantom of the head human model under the same condition with the CT simulation room. Results: The Hounsfield unit (HU) of the bolus measured by CT was $52{\pm}37.1$. The dose of TPS was 186.6 cGy, 193.2 cGy and 190.6 cGy at the M3 Wax bolus measurement points of A, B and C, and the dose measured three times at Mostet was $179.66{\pm}2.62cGy$, $184.33{\pm}1.24cGy$ and $195.33{\pm}1.69cGy$. And the error rates were -3.71 %, -4.59 %, and 2.48 %. The dose measured with EBT3 film was $182.00{\pm}1.63cGy$, $193.66{\pm}2.05cGy$ and $196{\pm}2.16cGy$. The error rates were -2.46 %, 0.23 % and 2.83 %. Conclusions: The thickness of the M3 wax bolus was 2 cm, which could help the treatment plan to be established by easily lowering the dose of the brain part. The maximum error rate of the scalp surface dose was measured within 5 % and generally within 3 %, even in the A, B, C measurements of dosimeters of EBT3 film and Mosfet in the treatment dose verification. The making period of M3 wax bolus is shorter, cheaper than that of 3D printer, can be reused and is very useful for the treatment of scalp malignancies as human tissue equivalent material. Therefore, we think that the use of casting type M3 wax bolus, which will complement the making period and cost of high capacity Bolus and Compensator in 3D printer, will increase later.

Dentofacial changes of non-orthodontically treated female patients with TMJ disk displacement: a longitudinal cephalometric study (교정 치료를 받지 않은 측두하악관절원반변위가 있는 여성 환자의 두부계측방사선사진을 이용한 안모 및 치열 변화 연구)

  • Han, Jung-Woo;Kim, Tae-Woo
    • The korean journal of orthodontics
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    • v.40 no.6
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    • pp.398-410
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    • 2010
  • Objective: The purpose of this study was to investigate the changes in dentofacial morphology of non-orthodontically treated female patients with TMJ disk displacement. Methods: The sample consisted of 25 Korean female patients with bilateral TMJ disk displacement who visited the Department of Orthodontics, Seoul National University Dental Hospital from 1996 to 2006. Disk displacements were diagnosed using the magnetic resonance imaging (MRI) of both TMJs. Baseline (T1) and follow-up (T2) lateral cephalograms were analyzed. The mean age of samples at T1 was $18.1{\pm}3.5$ years (range 14.2 - 25.8 years) and at T2, $21.1{\pm}3.5$ years (range 16.2 - 28.0 years). The mean observation period was $3.0{\pm}1.9$ years. Descriptive statistics for each variable were calculated at baseline (T1) and follow-up (T2) stages, and during the observation period (T2-T1). Results: Skeletal changes were found in 64% of the non-orthodontically treated female patients with TMJ disk displacement during the observation period. The L1 to Mandibular plane distance (mm) increased significantly by 0.8 mm (p < 0.01). But there were no significant differences in the other dental relationship variables (overjet, overbite, U1 to palatal plane) during the observation period. Most patients with skeletal changes showed a backward rotation of the mandible. The ratio of the rotation was a decrease of SNB by $0.43^{\circ}$ for every $1^{\circ}$ increase of FMA (Spearman rho = -0.660, P < 0.01). A few patients showed a distal shift of the mandible without rotation or significant changes in the vertical dimension. Conclusions: During observation periods without orthodontic treatment, non-growing patients with TMJ disk displacement showed dentoskeletal changes, mainly backward rotation of the mandible.

SEMI-LONGITUDINAL STUDY ON GROWTH AND DEVELOPMENT OF CHILDREN AGED 6 TO 17 Part II : GROWTH CHANGE OF CRANIOFACIAL SOFT TISSUE (한국인 6-17세 아동의 성장과 발육에 관한 준종단적 연구 제 2 세부과제 : 두개 및 안면 연조직의 성장변화)

  • Park, Young-Chel;Lee, Kee-Joon;Han, Hee-Kyoung;Lee, Jang-Yeol
    • The korean journal of orthodontics
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    • v.26 no.4
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    • pp.325-340
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    • 1996
  • Along with traditional goal of 'straightening teeth', today's orthodontics put more and more emphasis on facial esthetics. Naturally, the importance of soft tissue, which dictates one's facial form, is noticed. There have been many cephalometric studies on growth of hard tissue ; however, only a few on that of soft tissue. In Korea, various methods of sampling, measuring and analysing were used to study soft tissue changes, and yet, soft tissue changes along with process of normal growth have not been studied. The author carried out this study as a part of semi-longitudinal study on craniofacial growth and development of Korean children from ages of six to seventeen. 409 boys and 436 girls who'd had no systemic disease for the last three years and shown normal developmental and occlusal status were chosen as subjects. Cephalometric X-rays were taken of each subject, and facial form, lip position & form, nose form, and lip thickness were measured. Mean values and standard deviations were calculated according to age and gender, and figures and tables were drawn accordingly. The following results were obtained: 1. In respect to facial form, boys showed growth for longer period compared to girls. Also, lower face showed higher growth rate than upper face. 2. There was not much change in thickness of upper and lower lips with age; however, they appeared more prominent compared to caucasian children. 3. Nose grew horizontally with age. 4. Horizontal thickness of lower face increased with age, and upper lip thickness at nose base[A-Sn(FH)] showed more growth than anywhere else.

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Relationship between maximum bite force and facial skeletal pattern (최대 교합력과 안면 골격 형태에 관한 연구)

  • Choi, Won-Cheul;Kim, Tae-Woo
    • The korean journal of orthodontics
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    • v.33 no.6 s.101
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    • pp.437-451
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    • 2003
  • The purpose of this study was to measure maximum bite force and to investigate its relationship with anteroposterior, vertical, and transverse facial skeletal measurements. From among the dental students at the College of Dentistry, forty subjects (26 male and 14 female) were selected. With two sets of strain gauge, maximum bite force at the right and left first molars and anterior teeth was measured in the morning and afternoon. After taking lateral and posteroanterior cephalograms, fifty and nineteen variables were evaluated, respectively Paired t-tests and an independent t-test were done and correlation coefficients were obtained. 1. The maximum bite force at the first molars was $68.0\pm13.9kg$. in males and $55.6\pm10.5kg$ in females (p<0.05) while the force at the anterior teeth was $8.4\pm4.9kg\;and\;1.1\pm3.4kg$ respectively (p<0.05). 2. Some tendency for a greater value of maximum bite force at the preferred side was observed but not statistically significant (p>0.05). 3. Significant difference was observed between the strong bite force group and the weak bite force group in some cephalometric and other measurements (p<0.05). N-S-Ar, S-Ar-Go, FH-Hl, IMPA and MMO showed a significant difference in posterior maximum bite force (P). N-S-Ar and FH-H1 also showed a significant difference in anterior maximum bite force (A). 4. Several cephalometric variables showed some correlation with maximum bite force (p<0.05). N-S-Ar, S-Ar-Go, UGA, FH-H6, FH-H1, body weight and MMO were significantly correlated with posterior maximum bite force (P). Go-Me, P-1 and IMPA were significantly correlated with anterior maximum bite force (A).

Correlations between dental and skeletal maturity (치아성숙도와 골성숙도의 상호연관성에 관한 연구)

  • Lee, Young-Mi;Kim, Kwang-Won;Yoon, Young-Jooh
    • The korean journal of orthodontics
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    • v.30 no.2 s.79
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    • pp.143-157
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    • 2000
  • To investigate the developmental stages of dental and skeletal maturation by ages and the correlations among dental maturity, skeletal maturity of cervical vertebrae, and that of hand-and-wrist, the author used the cephalograms, orthopantomograms, and hand-and-wrist radiograms of 1055 patients (male 458, female 597) aged 7 to 20 years old. In the cephalograms, the skeletal maturity stages of each bone were mainly assessed by Hassel and Farman's cervical vertebrae maturation indicators (CVMI) method. In the orthopantomograms, the dental maturity stages of each tooth were mainly assessed by Nolla's tooth calcification stages method. In the hand-and-wrist radiograms, the skeletal maturity stages of each bone were mainly assessed by Fishman's skeletal maturity indicators (SMI) method. The results were as follows. 1. There was a high correlation among dental maturity, skeletal maturity of cervical vertebrae, and that of hand-and-wrist in the both sexes (P<0.001). 2. There was a high correlation (r=0.91-0.93) between skeletal maturity of cervical vertebrae and that of hand-and-wrist. 3. There was a high correlation (r>0.8) between skeletal maturity of hand-and-wrist and maturity of upper and lower canine, first premolar, and second premolar. 4. There was high a correlation(r=0.8) between skeletal maturity of cervical vertebrae and maturity of upper canine. 5. By the ages, dental maturity, skeletal maturity of cervical vertebrae, and that of hand-and-wrist were obtained in the both sexes. In summary, dental maturity, skeletal maturity of cervical vertebrae, and that of hand-and-wrist we of sufficient diagnostic worth as an index to predict adolescent growth.

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