1.Comparative Study of Panoramic Mandibular Parameters in Postmenopausal Osteoporotic women.
Cheol Hun KIM ; Sang Hun SHIN ; Dong Kyu YANG
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2000;26(5):519-526
Osteoporosis has recently been recognized as a major health problem in the elderly population. The disorder is manifested as a loss of bone mass accompanied by structural alteration of bone and increased incidence of fracture. Mandible also may be affected. So, I evaluated panoramic views of 66 postmenopausal women for finding the possibility of useful diagnostic mandibular parmeters of osteoporosis. To know the correlationship between skeleton and mandible, the average of the bone mineral density of lumbar from 2nd to 4th by the dual energy X-ray absorptiometry(DEXA, LUNAR DPZ. USA), and age and mandibular parameters, that is, the number of residual teeth, alveolar ridge resorption ratio, panoramic mandibular index (PMI), mandibular cortical width (MCW), angular cortical thickness (ACT), ramus cortical thickness (RCT), morphology of mandibular inferior cortical (MIC) were compared. And I divided the all tested women to the osteoporotic group and non-osteoporotic group by the use of T-score-2.0, which was derived from skeletal bone mineral density (BMD). To find the correlationship of the each group with mandibular parameters, t-test and discriminant analysis were done. The results of the t-test were that all parameters were highly related with 2 groups (p<0.05). Especially ACT, MIC, age have had even higher correlationship than others (p<0.001). The results of the discriminant analysis by the use of these ACT, MIC and age were that the discriminant function was Z =-2.973+(-1.447)x(ACT)+1.131x(MIC score)+(0.052)x(age), the cutting score was 0.257 and the classification accuracy was 84.8%. Therefore I suggest that the consideration of the angular cortical thickness (ACT), the age of patient and the morphology of mandibular inferior cortical(MIC) may help find the osteoporosis.
Aged
;
Alveolar Process
;
Bone Density
;
Classification
;
Female
;
Humans
;
Incidence
;
Mandible
;
Osteoporosis
;
Skeleton
;
Tooth
2.A STUDY OF THE STRESS DISTRIBUTION OF THE ABUTMENT AND SUPPORTING TISSUES ACCORDING TO THE SLOPES AND TYPES OF GUIDING PLANES OF THE LAST ABUTMENT IN DISTAL EXTENSION REMOVABLE PARTIAL DENTURE USING THREE DIMENSIONAL FINITE ELEMENTANALYSIS METHOD.
Yang Kyo KIM ; Cheong Hee LEE ; Kwang Hun JO
The Journal of Korean Academy of Prosthodontics 1999;37(5):581-596
The purpose of this study was to investigate the stress distribution of the abutment and supporting tissues according tot he slopes and types of the guiding plane of distal extension removable partial dentures. The 3-dimensional finite element method was used and the finite element models were prepared as follows. Model I : Kratochvil type guiding plane with 90degree to residual ridge Model II : Kratochvil type guiding plane with 95degree to residual ridge Model III : Kratochvil type guiding plane with 100degree to residual ridge Model IV : Krol type guiding plane with 90degree to residual ridge Distal extension partial denture which right mandibular first and second molar were lost was used and the second premolar was prepared as primary abutment with RPI type retainer. Then 150N of compressive force was applied to central fossae of the first and second molars and von Mises stress and displacement were measured. The results were as follows : 1. Model I and Model IV showed a similar stress distribution pattern and the stress was concentrated on the apex of the root of the abutment. 2. The stress was increased and concentrated on mesial side of the root of the abutment in Model II. The stress was concentrated on buccal and mesiobuccal side of the root of the abutment in Model III. 3. In Model I, the root of the abutment displaced and twisted a little in clockwise. In Model IV, the root of the abutment displaced to distolingually at apical region of the root and mesiobucally at cervical region of the root. 4. In Model II, the root of the abutment displaced to mesiolingually at apical region of the root and more displaced and twisted in counterclockwise at cervical region of the root. In Model III, the root of the abutment displaced to mesiobucally at apical region of the root and more displaced and twisted in clockwise at cervical region of the root.
Bicuspid
;
Denture, Partial
;
Denture, Partial, Removable*
;
Molar
3.CT Appearance of Internal Hernia:Whorling Sign of Mesentery and Mesenteric Vessels.
Tae Hun KIM ; Won Ho KIM ; Geun Seok YANG ; Sung Woo KIM ; Duk Sik KANG
Journal of the Korean Radiological Society 1995;32(2):297-302
PURPOSE: To evaluate CT findings of internal hernia. MATERIALS AND METHODS: Three patients with internal hernia had abdominal CT scans and two of them had small bowel follow through examinations. The CT features of two patients with retroanastomotic and one patient with left paraduodenal hernia were evaluated and correlated with small bowel follow through examinations, and surgical findings. Two patients with retroanastomotic hernia had a history of subtotal gastrectomy with antecolic gastrojejunostomy. The diagnosis of internal hernia was made on the basis of surgical find ings in two patients of retroanastomotic hernia, and characteristic barium study findings in one patient of left paraduodenal hernia. RESULTS: The small bowel follow through examination showed small bowel loops gathered in a circumscribed mass in the left mid abdomen, and delay in passage through these loops. In case of left paraduodenal hernia, abrupt narrowing of the distal duodenum could be identified. The characteristic CT findings of all three patients were whorling of the mesentery and mesenteric vessels in the left mid-abdomen. In the patient with left paraduodenal hernia, after resolution of the gastrointestinal symptoms, a follow-up CT scan showed spontaneous disappearance of whorling of the mesentery and mesenteric vessels suggesting spontaneous resolution of the hernia. In the other two cases, upon exploration of the abdomen, dilatation of afferent duodenum caused by adhesion between ligament of Treitz and adjacent bowel walls, and retro- anastomotic herniation of the efferent loops were found. CONCLUSION: The usual diagnosis of internal hernia is based on the appearance of the small bowel follow through examination. However, we consider that the whorling appearance(we call it whorling sign) of the mesentery and mesenteric vessels on CT scan is also suggestive of internal hernia in patients under clinical suspicion.
Abdomen
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Barium
;
Diagnosis
;
Dilatation
;
Duodenum
;
Follow-Up Studies
;
Gastrectomy
;
Gastric Bypass
;
Hernia
;
Humans
;
Ligaments
;
Mesentery*
;
Tomography, X-Ray Computed
4.Radiologic Findings of the Anthrax: Focus on Alimentary Anthrax.
Tae Hun KIM ; Duk Sik KANG ; Won Ho KIM ; Geun Seok YANG ; Sung Woo KIM
Journal of the Korean Radiological Society 1995;33(4):599-603
PURPOSE: To evaluate the radiologic findings of alimentary anthrax. MATERIALS AND METHODS: 19 patients with alimentary anthrax, which was caused by ingestion of contaminated beef, were included in this study. The diagnosis was made .b.y demonstration of Bacillus anthracis in smear and culture of the contaminated meat. We evaluated the clinical manifestations and the findings of thoracic, abdominal radiographs, cervical, abdominal ultrasonograms and abdominal CT scans. RESULTS: Out of the 19 patients with the alimentary infection, 9 had oropharyngeal form, 18 had abdominal form and 8 had combination of oropharyngeal and abdominal form. The patients had general symptoms and signs such as fever, chill, myalgia. Clinical symptoms and signs were sore throat, throat injection, throat ulcer and patch in oropharyngeal form, and nausea, vomiting, abdominal pain, diarrhea, and gross GI bleeding in abdominal form. Radiologic findings included enlarged cervical lymph nodes(36%) in oropharyngeal form, and paralytic ileus(26%), ascites(26%), hepatomegaly(21%), enlarged mesenteric lymph nodes(26%), small bowel wall thickening(5%) in abdominal form. In two patients, late complications occurred as intestinal obstruction due to ileal stricture with perforation, and inflammatory changes of pelvic cavity due to ileovesical fistula. CONCLUSION: Radiologic findings of alimentary anthrax are difficult in differentiation from those of other inflammatory bowel disease, but those radiologic findings with clinical manifestations may be helpful in diagnosis and evaluation of disease process in patients with alimentary anthrax.
Abdominal Pain
;
Anthrax*
;
Bacillus anthracis
;
Constriction, Pathologic
;
Diagnosis
;
Diarrhea
;
Eating
;
Fever
;
Fistula
;
Hemorrhage
;
Humans
;
Inflammatory Bowel Diseases
;
Intestinal Obstruction
;
Meat
;
Myalgia
;
Nausea
;
Pharyngitis
;
Pharynx
;
Tomography, X-Ray Computed
;
Ulcer
;
Ultrasonography
;
Vomiting
5.The Operation of Unaffected Normal Eye in Unilateral Ptosis.
Chun Hun LEE ; Yong Ran KIM ; Hi Soo KIM
Journal of the Korean Ophthalmological Society 1997;38(9):1622-1627
Moderate to severe unilateral ptosis has previously been treated with levator resection or frontalis sling and cosmetic double fold in the opposite eyelid. This method often resulted in undesirable asymmetrical lid lag phenomenon in down gaze. From December 1991 to December 1994, we treated 65 cases of unilateral ptosis with frontalis sling or levator resection, and simultaneously cosmetic frontalis sling have been performed in the unaffected normal eyes of 41 patients and cosmetic double fold have been performed in the unaffected normal eyes of 11 patients. After 6 months of operation, authors survey the patients content. The number of cases of content were 4(36.36%) in 11 cosmetic double fold group and 31(75.6%) in 41 cosmetic frontalis sling group. The content after cosmetic frontalis sling was higher than cosmetic double fold. Asymmetrical lid lag phenomenon on downward gaze which is inevitable complication postoperatively was reduced by means of cosmetic frontalis sling of unafeected normal eye in unilatral ptosis. The authors expect that the patient will be more satisfied with the result of symmetrical lid lag in down gaze after cosmetic frontalis sling of unaffected normal eye in aesthetic aspect.
Eyelids
;
Humans
6.Analysis of medical student's book reports on Cronin's The Citadel: would young doctors give up ideals for prestige and wealth?.
Se Won HWANG ; Hun KIM ; Ae Yang KIM ; Kun HWANG
Korean Journal of Medical Education 2016;28(2):231-235
PURPOSE: The purpose of this study is to find what medical students think the reward for their future work should be and whether they would keep their ideals or abandon them for prestige and wealth by analyzing the book reports of Cronin's The Citadel. METHODS: Participants were 50 medical students of junior class. A month before the classroom lecture, the book and digital video disk were provided. Students had discussions in groups of seven and wrote book reports which include answers of three questions. RESULTS: Regarding what should be the reward for the medical doctor, two-thirds of students (66.7%) answered with spiritual compensation, while one-third (33.3%) chose material reward. In the situation presented to Manson, three-fifths (60.0%) answered they would keep their ideals (idealist), while the remaining two-fifths (40.0%) decided they would abandon them. Less than one-third of students (30.0%) answered they would reveal the corruptions of the doctor's society, while two-thirds (64.0%) would not. CONCLUSION: The larger number of idealists who prefer spiritual reward rather than a material reward represents the innocence of youth as in portrayed in The Citadel.
Adolescent
;
Compensation and Redress
;
Humans
;
Medicine in Literature
;
Reward
;
Students, Medical
7.The effect of low temperature aging on the mechanical property & phase stability of Y-TZP ceramics.
Hyung Tae KIM ; Jung Suk HAN ; Jae Ho YANG ; Jai Bong LEE ; Sung Hun KIM
The Journal of Advanced Prosthodontics 2009;1(3):113-117
STATEMENT OF PROBLEM: Recently Yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) has been introduced due to superior flexural strength and fracture toughness compared to other dental ceramic systems. Although zirconia has outstanding mechanical properties, the phenomenon of decrease in the life-time of zirconia resulted from degradation in flexural strength after low temperature aging has been reported. PURPOSE: The objective of this study was to investigate degradation of flexural strength of Y-TZP ceramics after various low temperature aging treatments and to evaluate the phase stability and micro-structural change after aging by using X-ray diffraction analysis and a scanning electron microscope (SEM). MATERIAL AND METHODS: Y-TZP blocks of Vita In-Ceram YZ (Vita Zahnfabrik, Bad Sackingen, Germany) were prepared in 40 mm (length) x 4 mm (width) x 3 mm (height) samples. Specimens were artificially aged in distilled water by heat-treatment at a temperature of 75, 100, 125, 150, 175, 200, and 225degrees C for 10 hours, in order to induce the phase transformation at the surface. To measure the mechanical property, the specimens were subjected to a four-point bending test using a universal testing machine (Instron model 3365; Instron, Canton, Mass, USA). In addition, X-ray diffraction analysis (DMAX 2500; Rigaku, Tokyo, Japan) and SEM (Hitachi s4700; Jeol Ltd, Tokyo, Japan) were performed to estimate the phase transformation. The statistical analysis was done using SAS 9.1.3 (SAS institute, USA). The flexural strength data of the experimental groups were analyzed by one-way analysis of variance and to detect statistically significant differences (alpha= .05). RESULTS: The mean flexural strength of sintered Vita In-Ceram YZ without autoclaving was 798 MPa. When applied aging temperature at below 125degrees C for 10 hours, the flexural strength of Vita In-Ceram YZ increased up to 1,161 MPa. However, at above 150degrees C, the flexural strength started to decrease. Although low temperature aging caused the tetragonal-to-monoclinic phase transformation related to temperature, the minimum flexural strength was above 700 MPa. CONCLUSION: The monoclinic phase started to appear after aging treatment above 100degrees C. With the higher aging temperature, the fraction of monoclinic phase increased. The ratio of monoclinic/tetragonal + monoclinic phase reached a plateau value, circa 75% above 175degrees C. The point of monoclinic concentration at which the flexural strength begins to decrease was between 12% and 54%.
Aged
;
Aging
;
Aluminum Oxide
;
Ceramics
;
Collodion
;
Dental Porcelain
;
Electrons
;
Humans
;
Phenothiazines
;
Tokyo
;
Water
;
X-Ray Diffraction
;
Yttrium
;
Zirconium
8.A Case of Adrenal Cavernous Hemangioma.
Jeong Oh LEE ; Seung Hun JEON ; Yang Hoo KIM ; In Gon KIM ; In Gi SEONG ; Bo Hyun HAN
Korean Journal of Urology 2000;41(6):803-806
No abstract available.
Hemangioma, Cavernous*
9.Adjusted Peak Urinary Flow Rate for Varying Age and Volume Voided in Healthy Korean Male.
Tae Hun KIM ; Dae Yul YANG ; Hayoung KIM
Korean Journal of Urology 1998;39(5):476-479
PURPOSE: Peak urinary flow rate is a widely used parameter in the diagnosis and evaluation of treatment erect of BPH because of its objectiveness and non-in vasiveness. The peak urinary flow rate, however is different with each voided volume in the same patient and tends to decrease even in an asymptomatic man with increasing ages. Therefore we need an adjusted peak urinary flow rate corresponding with the age and voided volume. This adjusted peak urinary flow rate can be used to evaluate the voiding function more easily in the same patient periodically or In the different patient of various voided volume and ages. MATERIALS AND METHODS: Data on age, volume voided and peak urinary flow rate were accumulated from 216 male aged from 10 to 80 who were free of voiding symptoms. All combinations of peak urinary flow rate, age and volume voided were tested for equation of bet fit by the least squares method with search for the equation providing least residual standard deviation with SAS package. RESULTS: When the peak urinary flow rate is defined as a function of age and voided volume, the equation is Q=35.01+0.086A-0.0031A2-1612/V(Q: peak urinary flow rate, A: age, V: voided volume). At the point of population means for volume voided(247.5ml) arid age(35.2) the reference peak urinary flow rate was 27.7m1/sec. Adjusted peak flow rate can be obtained by subtracting the difference between the measured and expected peak flow rate(expected minus measured) from the reference peak flow rate. To make the adjusted peak flow rate obtained easily with measured peak flow rate, age and voided volume nomogram that incorporates the equation has been designed. In our nomogram an adjusted peak flow rate < 19.9 ml/sec or > 1.3 standard deviation below mean should be considered suspicious for obstruction. CONCLUSIONS: Nomogram for adjusted peak flow rate that incorporates the age, voided volume and measured peak flow rate would be satisfactory for clinical use.
Diagnosis
;
Humans
;
Least-Squares Analysis
;
Male*
;
Nomograms
10.Comparison of polymer-based temporary crown and fixed partial denture materials by diametral tensile strength.
Seung Ryong HA ; Jae Ho YANG ; Jai Bong LEE ; Jung Suk HAN ; Sung Hun KIM
The Journal of Advanced Prosthodontics 2010;2(1):14-17
PURPOSE: The purpose of this study was to investigate the diametral tensile strength of polymer-based temporary crown and fixed partial denture (FPD) materials, and the change of the diametral tensile strength with time. MATERIAL AND METHODS: One monomethacrylate-based temporary crown and FPD material (Trim) and three dimethacrylate-based ones (Protemp 3 Garant, Temphase, Luxtemp) were investigated. 20 specimens (the empty set 4 mm x 6 mm) were fabricated and randomly divided into two groups (Group I: Immediately, Group II: 1 hour) according to the measurement time after completion of mixing. Universal Testing Machine was used to load the specimens at a cross-head speed of 0.5 mm/min. The data were analyzed using one-way ANOVA, the multiple comparison Scheffe test and independent sample t test (alpha = 0.05). RESULTS: Trim showed severe permanent deformation without an obvious fracture during loading at both times. There were statistically significant differences among the dimethacrylate-based materials. The dimethacrylate-based materials presented an increase in strength from 5 minutes to 1 hour and were as follows: Protemp 3 Garant (23.16 - 37.6 MPa), Temphase (22.27 - 28.08 MPa), Luxatemp (14.46 - 20.59 MPa). Protemp 3 Garant showed the highest value. CONCLUSION: The dimethacrylate-based temporary materials tested were stronger in diametral tensile strength than the monomethacrylate-based one. The diametral tensile strength of the materials investigated increased with time.
Acrylic Resins
;
Bisphenol A-Glycidyl Methacrylate
;
Collodion
;
Composite Resins
;
Crowns
;
Denture, Partial, Fixed
;
Methacrylates
;
Polymethacrylic Acids
;
Tensile Strength