1.Three dimensional finite element stress analysis of five different taper design implant systems.
Sang Ki BYUN ; Won Hee PARK ; Young Soo LEE
The Journal of Korean Academy of Prosthodontics 2006;44(5):584-593
STATEMENT OF PROBLEM: Dental implant which has been developed gradually through many experiments and clinical applications is presently used to various dental prosthetic treatments. To conduct a successful function of implant prosthesis in oral cavity for a long time, it is important that not only structure materials must have the biocompatibility, but also the prosthesis must be designed for the stress, which is occurred in occlusion, to scatter adequately of load support. Therefore, it is essential to give the consideration about the stress analysis of supporting tissues for higher successful rates. PURPOSE: Recently, many implant manufacturing company produce various taper design of root form implant, the fixture is often selected. However, the stress analysis of taper form fixture still requires more studies. MATERIAL AND METHOD: This study we make the element models that five implant fixture; Branemark system(Nobel Biocare, Gothenberg, Sweden), Camlog system(Altatec, Germany), Astra system(Astra Tech, Sweden), 3i system(Implant Innovations Inc, USA), Avana system(Osstem, Korea)were placed in the area of mandibular first premolar and prosthesis fabricated, which we compared with stress distribution using the three-dimension finite element analysis under two loading condition. RESULTS: This study compares the aspect of stress distribution of each system with the standard of Von mises stress, among many resulted from finite element analysis so that this research gets the following results. 1. In all implant system, oblique loading of maximum Von mises stress of implant, alveolar bone and crown is higher than vertical loading of those. 2. Regardless of loading conditions and type of system, cortical bone which contacts with implant fixture top area has high stress, and cancellous bone has a little stress. under the vertical loading, maximum Von mises stress is more higher in order of Branemark, Camlog, Astra, 3i, Avana. under the horizontal loading, maximum Von mises is more higher in order of Camlog, Branemark, Astra, 3i, Avana.
Bicuspid
;
Crowns
;
Dental Implants
;
Finite Element Analysis
;
Mouth
;
Prostheses and Implants
2.Effect of Two-year Course of Food and Nutrition on Improving Nutrition Knowledge, Dietary Attitudes and Food Habits of Junior College Female Students.
Korean Journal of Community Nutrition 2010;15(6):750-759
This study was conducted to investigate the effect of two-year course of food and nutrition on improving nutrition knowledge, dietary attitudes and food habits of junior college female students by questionnaires. The subjects were 108 college female students enrolled in the department of food and nutrition in Gyeonggi area. The results were as follows: There were no significant changes in the weights and BMI (Body Mass Index) after 2-yr course of food and nutrition. Nutrition knowledge (14.7 vs 16.3, p < 0.001) and dietary attitude (34.3 vs 35.8, p < 0.01) increased significantly after 2-yr course. However, no significant changes in food habit were observed. Among nutrition knowledge, the scores of functions (4.5 vs 5.2, p < 0.001) and understanding (6.7 vs 7.4, p < 0.01) of nutrients were significantly increased. The recognition of nutrition knowledge increased significantly (83.1 vs 95.7, p < 0.001). Among food habit, dietary habit (13.2 vs 12.5, p < 0.01) and health related habit (15.6 vs 14.6, p < 0.001) were significantly lowered after 2-yr course. The change in dietary attitudes showed significantly positive correlation with food habit changes (p < 0.05). These results showed that 2-yr course of Food and Nutrition had improved the nutrition knowledge and dietary attitudes. Therefore, providing the more systematic and appropriate nutrition education to students during their study period will be improved dietary attitudes and food habits.
Female
;
Food Habits
;
Humans
;
Surveys and Questionnaires
;
Weights and Measures
3.A clinical study of vascularized osteocutaneous fibular transfer to the tibia.
Kwang Suk LEE ; Snag Won PARK ; Ki Hoon KANG ; Young Soo BYUN
The Journal of the Korean Orthopaedic Association 1993;28(6):2131-2142
No abstract available.
Tibia*
4.Beneficial Effects of Estrogen in Syndrome X of Postmenopausal Women.
Dongsoo KIM ; Ki Hyun BYUN ; Hyuck Moon KWON ; Yong Won YOON ; Bum Kee HONG ; Kyung Soon SONG ; Hyun Seung KIM
Korean Circulation Journal 1999;29(3):298-305
BACKGROUND: There are many reports about the correlation between cardiovascular disorders and estrogen deficiency in postmenopausal women. The purpose of current study is to know that postmenopausal estrogen therapy may affect the lipid metabolism and endogenous fibrinolytic system and exercise tolerance. METHOD: We investigated the relation of estrogen treatment (srogen 0.625 mg/day) to serum lipid levels, angiotensin converting enzyme activity, plasminogen activator inhibitor-1 and parameters of treadmill test in 22 postmenopausal women of normal coronary artery with abnormal exercise test complained with chest pain accompanied by postmenopausal symptoms. RESULTS: Estrogen treatment significantly elevated the serum HDL-cholesterol level (42.8 to 50.1 mg/dl, p<0.05) and reduced the PAI-1 level (16.2 to 10.4 ng/dl, p<0.01) without considerable side effects. During the exercise test, the positivity appearance time and total exercise duration is significantly increased after estrogen treatment. CONCLUSION: The postmenopausal use of estrogen favorably changed the lipid level, fibrinolytic system and might improve the microcirculation which may protect against the ischemic heart disease risk without significant side effects.
Chest Pain
;
Coronary Vessels
;
Estrogens*
;
Exercise Test
;
Exercise Tolerance
;
Female
;
Humans
;
Lipid Metabolism
;
Microcirculation
;
Myocardial Ischemia
;
Peptidyl-Dipeptidase A
;
Plasminogen Activator Inhibitor 1
;
Plasminogen Activators
;
Postmenopause
5.Clinical Result of 105 Cases Overcorrected Temporally after LASIK: 6 Months follow-up.
Journal of the Korean Ophthalmological Society 1999;40(9):2458-2463
This study aimed to evaluate the refractive and visual results of the cases temporally overcorrected after laser in situ keratomileusis (LASIK). Among 582 myopic eyes that underwent LASIK using VISX STAR from March 1997 to October 1998, 105 eyes were overcorrected more than one diopter (D) one week after LASIK. 105 eyes were divided into three groups according to their spherical equivalent (SE) at one week: Group l (> or = 3D, 9 eyes), group ll (2-2.9D, 14 eyes), and group lll (1-1.9D, 82 eyes).Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), SE, and complications were studied one day, one week, two months, and six months after LASIK. The mean preoperative SE was -11.17 +/-2.57D in group l,-9.40 +/-2.91D in group lland -8.09 +/-1.92D in group lll. At 6 months, the mean SE was 1.81 +/-1.61D, 0.04 +/-0.43D and -0.37 +/-0.76D in group l, ll and lll, respectively. The mean regression of SE from one day to six months was 1.85D, 2.27D and 1.73D in group l,ll and lll, respectively (p>0.05). The proportion of eyes that lost two or more lines of UCVA after LASIK compared to preoperative BCVA was 33.3% in group l, 10% in group ll, and 9.2% in group lll. There were central island (5 eyes), capsular wrinkling (3 eyes), free cap (1 eye), subepithelal metalic debris (1 eye), epithelial ingrowth (1 eye)as complications in all groups. With these results it might be concluded that hyperopia less than 3D one week after LASIK is temporary and disappears 6 months after surgery without any additional treatment, whereas hyperopia equal or more than 3D one week after LASIK still showed hyperopic refraction even after 6 months. Therefore, these eyes need further evaluation for the correction of hyperopia.
Follow-Up Studies*
;
Hyperopia
;
Keratomileusis, Laser In Situ*
;
Visual Acuity
6.Effect of Cataract Surgery through Clear Corneal Incision in Glaucomatous Eyes with Filtering Blebs.
Sung Won BYUN ; Chan Ki PARK ; Myung Douk AHN
Journal of the Korean Ophthalmological Society 1999;40(6):1630-1635
The small-incision cataract surgery by phacoemulsification with foldable posterior chamber lens implantation have recently permitted new options for combined trabeculectomy with cataract extraction. In the present study, we performed phacoemulsification and foldable intraocular lens implantation using small clear corneal incision in 20 patients with 22 glaucomatous eyes who had previously undergone trabeculectomy and determined its effects on visual acuity, intraocular pressure, the number of medications applied, and status of the filtering blebs. The mean follow-up period was 10.1 months and the mean time interval between the two surgeries was 14.7 months. The mean best corrected visual acuity was 0.19 preoperatively and 0.60 postoperatively and the postoperative visual acuity had improved in 19 eyes(86.4%). The mean(+/-standard deviation, SD) preoperative IOP was 16.7+/-5.88 mmHg and the mean(+/-SD) postoperative IOP at final visit was 15.5+/-4.07 mmHg. Postoperatively, the IOPs remained well controlled in 20 eyes(90.9%) without additional ocular hypotensives and required additional medications for control in 2 eyes(9.09%). And the funictioning bleb failures occurred in 5 eyes(22.7%). We found the procedure to be effective in restoring vision while controlling intraoperative pressure and preserving the filtering blebs.
Blister*
;
Cataract Extraction
;
Cataract*
;
Follow-Up Studies
;
Humans
;
Intraocular Pressure
;
Lens Implantation, Intraocular
;
Phacoemulsification
;
Trabeculectomy
;
Visual Acuity
7.A Case of Primary Malignant Leptomeningeal Melanomatosis.
Yeung Ki LEE ; Yeung Ju BYUN ; Choong Seo PARK ; Won Hee CHOI
Journal of the Korean Neurological Association 1991;9(3):357-361
Primary malignant melaomatosis of leptomeninges is uncommon, not reported in the Korea to this time. Primary melanomatosis of leptomeninges are not associated with any specific clinical or radiological symptoms. The diagnosis was made by ultrastructural demonstration of malignant melanoma cells from CSF. The patient is 23 years male, who has had meningeal irritating symptoms such as intermittent headache. Nausea, vomiting and disturbed consciousness. Brain CT and MRI showed no mass lesion but cytology of cerebrospinal fluid revealed malignant melanoma cells. There was no evidence of extracerebral melanoma.
Brain
;
Cerebrospinal Fluid
;
Consciousness
;
Diagnosis
;
Headache
;
Humans
;
Korea
;
Magnetic Resonance Imaging
;
Male
;
Melanoma
;
Nausea
;
Vomiting
8.Results of Combined Procedures versus Two-Stage Operation using Small Incision in Patients with Cataract and Glaucoma.
Sung Won BYUN ; Chan Ki PARK ; Tae Won HAHN ; Man Soo KIM
Journal of the Korean Ophthalmological Society 1999;40(9):2561-2566
To compare the result of small-incision combined procedure with that of two-stage procedure, the authors retrospec- tively reviewed 21 patients (23 eyes) who underwent small-incision combined cataract and glaucoma surgery (group 1) and 21 patients (23 eyes) who underwent small-incision cataract surgery after trabeculectomy (group 2). Intraocular pressure (IOP), visual acuity, bleb status, antiglaucoma medications and complications were analyzed.The mean follow-up period was 12.9 (2.3~30.1) months in group 1 and 13.9 (2.1~35.9) months in group 2. The mean preoperative IOP was 21.1 +/-6.6mmHg in group 1 and 26.6 +/-9 .3 mmHg in group 2. The mean postoperative IOP was 14.3 +/-3 .7 mmHg and 15.8 +/-3.1 mmHg in group 1 and 2, respectively. At last visit,13 eyes (56.5%) in group 1 and 12 eyes (52.2%)in group 2 had functioning blebs, and 21 eyes (91.3%) in group 1 and 17 eyes (73.9%) in group 2 had well controlled postoperative IOP without antiglaucoma medications.Rupture of posterior capsule,bleb site leakage, hypotony occurred in both groups; button hole (1 eye in group 1) and hyphema (2 eyes in group 2) were observed. These results indicate that the small-incisioncombined cataract and glaucoma surgery may be as safe and effective as the two-stage procedure.
Blister
;
Cataract*
;
Follow-Up Studies
;
Glaucoma*
;
Humans
;
Hyphema
;
Intraocular Pressure
;
Trabeculectomy
;
Visual Acuity
9.Comparison of Effects of Topical, Pinpoint and Retrobulbar Anesthesin in Cataract Surgery using Clear Corneal Incision.
Jeong Bong SEO ; Sung Won BYUN ; Jae Ho KIM ; Choun Ki JOO
Journal of the Korean Ophthalmological Society 1998;39(8):1716-1722
In order to evaluate the efficacy of topical anesthesia as an alternative to pinpoint or retrobulbar anesthesia in clear corneal cataract surgery, ninety patients were randomly assigned to the topical(n=30), pinpoint(n=30), or retrobulbar(n=30) anesthesia groups prospectively. All procedures including CCC, phacoemulsification, and foldable IOL implantation were performed using a temporal clear corneal approach by one surgeon(Joo). visual rehabilitation, change of astigmatism, degree of pain, comfortability, cooperation, and intraoperative and postoperative complications were compared. Intraocular pressure was higher in pinpoint anesthesia than in topical anesthesia at the beginning point of operation(p<0.05). Four hours after surgery, topical of pinpoint anesthesia group had significantly better visual acuity than retrobulbar anesthesia group(p<0.05). Pain score in topical anesthesia was marginally higher than that in retrobulbar anesthesia during the phacoemulsification. Comfortability was prominent in topical anesthesia group. There was no difference among the groups in change of astigmatism, cooperation and risk of serious complicatins. With these results it was found that topical anesthesia would be a safe, effective alternative to pinpoint or retrobulbar anesthesia in cataract surgery using clear corneal incision.
Anesthesia
;
Astigmatism
;
Benzocaine*
;
Cataract*
;
Humans
;
Intraocular Pressure
;
Phacoemulsification
;
Postoperative Complications
;
Prospective Studies
;
Rehabilitation
;
Visual Acuity
10.The Validity and Reliability of Addiction Severity Index in Alcoholic Patients.
Duk Ki LEE ; Woo Suk JANG ; Seok Gu SEOL ; Suk Ja YOUN ; Jin Seok CHO ; Won Tan BYUN
Journal of Korean Neuropsychiatric Association 1997;36(6):1033-1040
OBJECTIVE: The purpose of this study was to evaluate the validity and reliability of Korean version of Addiction Severity Index for the systematic diagnosis and evaluation of alcoholism. METHODS: The authors selected 65 alcoholic patients with the criteria of DSM-VI. RESULTS: The results were as follows: 1) The exception of the significant correlation between psychiatric and the family/social problem area, the 6 sections of ASI were mutually independent. 2) There was significant inter-rater reliability in all sections of ASI. 3) In medical, alcohol use, family/social and psychiatry section, the calculation of composite score showed reasonable level of item consistency. In all sections, there was significant correlation between composite scores and severity ratings of corresponding section. 4) The important items of each section were most highly correlated with their corresponding severity ratings except two sections. 5) In the multiple regression analysis, the amount of variance accounted far by the most important 4 items were 83% in medical section, 45% in employment/support,43% in alcohol use section, 55% in legal section,53% in family/social section and 84% in psychiatric section. 6) Severity rating of psychiatric section was significantly correlated with the scores of MMFI, MAST and SCL-90-R. CONCLUSION: The result suggests that Korean version of the ASI showed relatively reasonable reliability and validity and it can be used in treatment and study of alcoholic patients.
Alcoholics*
;
Alcoholism
;
Diagnosis
;
Humans
;
Reproducibility of Results*