1.A photoelastic study of the stress distribution in the alveolar bone by various molar uprighting springs.
Korean Journal of Orthodontics 1991;21(2):353-365
This study was performed to analyze the effects of forces to the alveolar bone by various molar uprighting spring such as helical uprighting spring. T-loop spring, Modified T-loop spring and open coil spring. The simplified two-dimensional photoelastic model was constructed with a lower left posterior quadrant containing the second molar, the first and second premolars and the canine, with the first molar missing. Several molar up righting springs were fabricated from 0.017 by 0.022 inch blue Elgiloy and applied to the photoelastic model. Two-dimensional photoelastic stress analysis was performed, and the stress distribution was recorded by photography. The results obtained were as follows; 1. In all the kinds of the springs, the center of rotation of the mandibular second molar was observed at the apical 1/5-1/6 between the alveolar crest and the root apex. 2. In all the kinds of the spring, the stress induced in the mesial root surface of the mandibular second molar was relatively homogeneous but there was some difference in the magnitude of the stress. 3. In the kinds of the springs, the distal crown tipping moment of the second molar was increased in turn as open coil spring, helical uprighting spring, T-loop spring, and modified T-loop spring. 4. The largest extrusive force was occured in the T-loop spring, intrusive force was occured in Modified T-loop spring only, and the largest distal tipping force was occured in open coil spring. 5. In the T-loop spring with activation, the stress induced in the mesial root surface of the second molar was increased gradually from the root apex to the alveolar crest and highly concentrated in the alveolar crest.
Bicuspid
;
Crowns
;
Molar*
;
Photography
2.Effects of bisphosphonate on alveolar bone resorption during experimental tooth movement in rats: Biochemical & histological observations.
Korean Journal of Orthodontics 1999;29(1):95-106
This study was performed to examine the effect of bisphosphonate, an inhibitor of bone resorption, on the formation of osteoclast and bone resorption during experimental tooth movement. Whether bisphosphonate has a cytotoxicity in high dose was also examined. Eighty-seven male Sprague-Dawley rats. Weighing 260-350g, were classified into normal (no appliance + 0.9% NaCl), control (appliance + 0.9% NaCl) and four bisphosphonate-treated( appliance + 0.8mg, 4mg, 20mg, or 100mg/kg) groups. The maxillary left first molar was moved mesially with the tippping movement using 50-70g of force. Bisphosphonate(etidronate disodium)was injected intraperitoneally with a dose of 0.8mg, 4 mg, 20mg, or 100mg/kg simultaneously with the application of the orthodontic force. They were killed at day 1.3 or 7after the application of the orthodontic force. The activities of serum acid phosphatase and lactate dehydrogenase (LDH) were assayed, and osteoclasts and the degree of bone resorption were examined histologically. The results obtained were as follows: 1. Acid phosphatase activities were significantly higher in the appliance groups, both control and bisphosphonate-treated( 4, 20 and 100mg/kg) groups, at days 1and 3 than these in normal. At day 1, bisphosphonate -treated(4, 20mg/kg) groups showed even higher acid phosphatase than control. However, at day 7, no significant difference was noted between the control and bisphosphonate-treated groups. 2. LDH activities in the 4, 20mg/kg bisphosphonate-treated groups were increased during the experimental periods examined, but there were no significant differences in the 0.8, 100mg/kg bisphosphonate-treated groups. 3. There was no bone resorption at day 1, but severe bone resorption was observed at days 3and 7 in the control. Bone resorption was reduced by bisphosphonate-treatment at day 3. Bone resorption observed at day 7 was similar between the control and bisphosphonate-treated groups. 4. Few osteoclasts were observed at the alveolar bone in the control and biosphosphnate-treated groups at day 1. At day 3. numerous osteoclasts were shown in the control, the degree of which was reduced in bisphosphonate-treated groups. These results suggest that the inhibition of the osteoclast formation was not the mechanism of bone resorption by the bisphosphonate-treatment during experimenal tooth movement. There was no distinct cytotoxicity with a high dose of bisphosphonate. And the drug should be administrated repeatedly to maintain the inhibitory effect of bone resorption.
Acid Phosphatase
;
Animals
;
Bone Resorption*
;
Humans
;
L-Lactate Dehydrogenase
;
Male
;
Molar
;
Osteoclasts
;
Rats*
;
Rats, Sprague-Dawley
;
Tooth Movement*
;
Tooth*
3.Comparison of slim bristled and V-shaped orthodontic toothbrushes in patients with fixed orthodontic appliances.
Korean Journal of Orthodontics 2009;39(6):383-392
OBJECTIVE: The purpose of this study was to evaluate the efficacy of a slim bristled toothbrush compared with a V-shaped orthodontic toothbrush in patients with fixed orthodontic appliances. METHODS: Thirty four orthodontic patients receiving edgewise treatment were randomly assigned to two groups, a slim bristled toothbrush (Nano silver slim care) and a V-shaped toothbrush (Oral-B). Plaque index, gingival index and bleeding index were recorded at the beginning of the study (baseline), 2 weeks, 4 weeks and 6 weeks after new toothbrushes were supplied and the results were analyzed statistically. RESULTS: No statistically significant differences were found for plaque index, gingival index and bleeding index between toothbrush groups during the 6 weeks. Plaque and gingival indices were decreased at 2 weeks and 4 weeks but increased at 6 weeks in both toothbrush groups. Bleeding index in the V-shaped toothbrush group showed the lowest value at 2 weeks then increased at 4 weeks and 6 weeks but in the slim bristled toothbrush group decreased from 2 weeks through 6 weeks to under baseline levels. Patients in their twenties had significantly lower values than teenagers in the slim bristled toothbrush group (p < 0.013). CONCLUSIONS: The results would suggest that both of the toothbrushes are equally effective but the use of a slim bristled toothbrush may be of benefit in promoting gingival health for fixed orthodontic appliance patients in their twenties and over.
Adolescent
;
Hemorrhage
;
Humans
;
Oral Hygiene
;
Orthodontic Appliances
;
Periodontal Index
;
Silver
4.Discomfort caused by the circumferential comfortable retainer (CCR) as a removable maxillary retainer.
Jin Hugh CHOI ; Cheol Hyun MOON
Korean Journal of Orthodontics 2010;40(5):325-333
OBJECTIVE: The aim of this study was to illustrate the circumferential comfortable retainer (CCR) as a removable maxillary retainer with good potential patient compliance and to evaluate the discomfort of the retainers including distorted speech, gagging sensation and appliance discomfort. METHODS: Sixty-six orthodontic patients (male, 23; female, 43; mean age, 23.42 +/- 10.19 years) who received orthodontic treatment with fixed orthodontic appliances were randomly assigned to two groups after debonding, a conventional wraparound retainer (CWR) group that fully covers the palate with an acrylic plate and a highly polished surface, and a circumferential comfortable retainer (CCR) group which has a horseshoe shaped base plate with three folds on the anterior region. A questionnaire that had a visual analog scale (VAS) which consists of a 100-mm horizontal line with 2 end-points labeled "no discomfort" on the left and "worst discomfort" on the right, with regard to distorted speech, gagging sensation and discomfort, was administered to patients after 4 weeks of retainer wear. The Mann-Whitney test was used to test the hypothesis that there was no difference between the two retainers. RESULTS: Comparing distorted speech and discomfort, the CCR group significantly had lower values than the CWR group (p < 0.05). Comparing gagging sensation, the CCR group had lower values than the CWR group but there were no statistically significant differences between groups (p = 0.146). CONCLUSIONS: In conclusion, the results suggest that the circumferential comfortable retainer (CCR) might facilitate patient compliance and thereby improve the maintenance of the fixed orthodontic treatment outcome.
Female
;
Gagging
;
Humans
;
Orthodontic Appliances
;
Palate
;
Patient Compliance
;
Surveys and Questionnaires
;
Sensation
;
Treatment Outcome
5.Non-surgical treatment and retention of open bite in adult patients with orthodontic mini-implants.
Cheol Hyun MOON ; Joo Sin LEE ; Hyun Sun LEE ; Jin Hugh CHOI
Korean Journal of Orthodontics 2009;39(6):402-419
Successful treatment of the non-growing patient with an open bite of either dental skeletal pattern often presents a difficult challenge. The morphologic pattern in anterior open bite is characterized by longer vertical dimensions, an increase in development of the maxillary posterior dento-alveolar structure and a steep mandibular plane. In such cases, molar intrusion would be a good remedy for treatment. This article reports the successful treatment and retention of two anterior open-bite cases. We used orthodontic mini-implants for treatment and a circumferential retainer with posterior bite block or skeletal fixed retainer for retention. The diagnostic criteria and mechanics for appropriate treatment are discussed. Our results suggest that open bite can be reduced successfully with intrusion of molars using orthodontic mini-implants (OMI) without orthognathic surgery, and that circumferential retainer with posterior bite block and skeletal fixed retainer are effective for retention.
Adult
;
Bites and Stings
;
Humans
;
Mechanics
;
Molar
;
Open Bite
;
Orthognathic Surgery
;
Retention (Psychology)
;
Vertical Dimension
6.Safety and effectiveness of Rixubis in patients with hemophilia B:a real-world, prospective, postmarketing surveillance study in South Korea
Eun Jin CHOI ; Tai ju HWANG ; Yong Mook CHOI ; Hugh Chul KIM ; Myung Chul YOO ; Haylee SONG ; Kayode BADEJO
Blood Research 2020;55(4):246-252
Background:
Rixubis (recombinant factor IX, nonacog gamma) is indicated for the control and prevention of bleeding episodes, perioperative management, and routine prophylaxis in hemophilia B patients. This real-world, postmarketing surveillance study aimed to evaluate the safety and effectiveness of Rixubis in adult and pediatric hemophilia B patients in South Korea.
Methods:
This prospective, observational, multicenter study (clinicaltrials.gov identifier: NCT029 22231) was conducted in hemophilia B patients between April 2015 and April 2019, who were observed for up to 6 months after the initiation of Rixubis treatment. Safety was evaluated based on the number and severity of adverse events (AEs) and serious AEs (SAEs). Hemostatic effectiveness was assessed by physicians and patients by using a four-point scale and rated as excellent, good, fair, or no response based on treatment type.
Results:
In all, 58 patients were enrolled from four centers by seven physicians during the study period. The safety and effectiveness analysis sets included 57 and 54 patients, respectively. Overall, 11 AEs were reported in eight patients (14.0%), of which three were SAEs and occurred in three patients (5.3%). All 11 AEs were reported as unexpected and mild in severity, with no anaphylactic reaction, and 10 AEs (90.9%) resolved. The majority of AEs (10) were unrelated to Rixubis. Of the 142 hemostatic effectiveness assessments, 123 (86.6%) were reported as good or excellent.
Conclusion
Rixubis demonstrated an acceptable safety and effectiveness profile in the treatment of bleeding, perioperative management, and prophylaxis in hemophilia B patients in a real-world setting in South Korea.
7.Development and Test of an Information Needs Scale for Outpatients Undergoing Chemotherapy.
Eun Hyun LEE ; Jin Hyuk CHOI ; Ho Yeong LIM ; Mi Sook SEO ; Hugh C KIM
Cancer Research and Treatment 2002;34(2):97-103
PURPOSE: The purpose of this study was to develop and test an Information Needs Scale for Korean outpatients undergoing chemotherapy (INS-C). MATERIALS AND METHODS: Thirty-three items of the INS-C had content validity based upon findings in the literature and the experiences of expert oncology physicians and nurses. Each item consisted of a five-point Likert scale from 1 (don't want to know) to 5 (want to know very much). The items were administered to 175 Korean outpatients undergoing chemotherapy. The data obtained was analysed using a factor analysis for construct validity and Cronabch's alpha for internal consistent reliability. RESULTS: From the factor analysis, six subscales were derived significantly. The six subscales explained 64.62% of the variance. The subscales were named Side-Effects/Investigative Tests (9 items), Spread of Disease (4 items), Financial Cost (2 items), Treatment (7 items), Activities/ Eating (6 items), and Interrelationships/Support (5 items). The Cronbach's alpha of the total INS-C was .95, and the alpha of the subscales ranged from .77 to .91. CONCLUSION: The present study suggests that the INS-C is a reliable and valid instrument to measure the information needs of outpatients undergoing chemotherapy. Health professionals caring for patients with cancer should assess the informational needs of their patients using a reliable and valid instrument and be prepared to provide accurate information.
Drug Therapy*
;
Eating
;
Health Occupations
;
Humans
;
Outpatients*
8.Validity of Superimposition Range at 3-Dimensional Facial Images
Hak Hee CHOI ; Jin Hyoung CHO ; Hong Ju PARK ; Hee Kyun OH ; Jin Hugh CHOI ; Hyeon Shik HWANG ; Ki Heon LEE
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons 2009;31(2):149-157
Adult
;
Humans
;
Hypogonadism
;
Mitochondrial Diseases
;
Nose
;
Ophthalmoplegia
;
Tokyo
9.Clinical characteristics and prognosis according to the classification of myelodysplastic syndrome.
Hyun Woo LEE ; Hyeoung Il KIM ; Jae Myoung CHOI ; Seok Yun KANG ; Jun Ho JANG ; Joon Seong PARK ; Jin Hyuk CHOI ; Ho Yeong LIM ; Hugh Chul KIM
Korean Journal of Medicine 2006;70(3):253-260
BACKGROUND: Myelodysplastic syndromes (MDS) are clonal hematologic stem cell disorders characterized clinically and morphologically by ineffective hematopoiesis. A consensus-defined French-American-British (FAB) classification and International Prognostic Scoring System (IPSS) for predicting outcome and planning therapy in MDS has been developed, but its prognostic value in a large and independent series remains unproven. So we investigate clinical characteristics and prognosis of MDS, according to French-American-British (FAB) classification and International Prognostic Scoring System (IPSS). METHODS: A retrospective analysis of 50 patients who were diagnosed as myelodysplastic syndrome at Ajou University Hospital was performed from November, 1994 to April, 2003. The patients with secondary MDS were excluded. All patients were classified according to the FAB classification and calculated prognostic scores for IPSS. Patients were evaluated for clinical features and for blood and bone marrow findings at the time of diagnosis, and were followed up for survival and leukemic progression. Survival curves were based on the Kaplan-Meier method. All reported p values less than or equal to 0.05 were regarded as stastistically significant. RESULTS: The peak age was in the fifth decade and the male to female ratio was 1.5:1. RA (36%) was observed most frequently. Thereafter, RAEB-t (26%), RAEB (24%), RARS (12%) and CMML (2%) were observed, respectively. The initial symptoms on admission were fever (24%), dizziness and headache (16%), general weakness (16%), hemorrhage (14%), dyspnea (12%), abdominal pain (4%) and vomiting (4%). Cytogenetic studies were performed in 34 patients with MDS. They were classified as good, intermediate, poor group by chromosome score of IPSS. The median survival was 16.4 months for the good group, 15 months for the intermediate, 10.3 months for the poor. The median survival according to FAB classified groups were RA (33.8 mo), RARS (12.5 mo), RAEB (16.4 mo), RAEB-t (6.7 mo) and CMML (1.3 mo). Survival according to IPSS scoring system were 67.2 months for low, 27.1 months for intermediate-1, 10.3 months for intermediate-2 and 6.0 months for high groups. These data were statistically significant (p<0.05). CONCLUSIONS: In our experiencies, FAB and IPSS classification would be good predictors in clinical outcomes. But, because of the heterogeneity of MDS, large multicenter studies will be needed to define the issue of a new classification for these disorders.
Abdominal Pain
;
Anemia, Refractory, with Excess of Blasts
;
Bone Marrow
;
Classification*
;
Cytogenetics
;
Diagnosis
;
Dizziness
;
Dyspnea
;
Female
;
Fever
;
Headache
;
Hematopoiesis
;
Hemorrhage
;
Humans
;
Male
;
Myelodysplastic Syndromes*
;
Population Characteristics
;
Prognosis*
;
Retrospective Studies
;
Stem Cells
;
Vomiting
10.A Case of Lymphomatoid Papulosis after Allogenic Bone Marrow Transplatation.
Jae Myoung CHOI ; Hyun Woo LEE ; Seok Yun KANG ; Jun Ho JANG ; Joon Seong PARK ; Jin Hyuk CHOI ; Ho yeong LIM ; Hugh Chul KIM ; Eun So LEE
Korean Journal of Hematology 2005;40(2):111-115
A twenty-year-old man developed pruritic papules on his right forearm on the 25th day after an allogeneic bone marrow transplantation from an HLA-matched related donor. The skin lesion turned out to be lymphomatoid papulosis, both histologically and immunophenotypically, not a GVHD skin lesion. Lymphomatoid papulosis is a chronic lymphoproliferative disease of the skin, characterized by recurrent crusts of pruritic papules, which initially appearing on the upper trunk and both extremities. The lesions heal spontaneously within 2~8 weeks, usually leaving slightly depressed oval scars. Histologically, the lesions show wedge-shaped dense dermal infiltrates of lymphoid cells, with numerous eosinophils, neutrophils and atypical lymphocytes. As much as 50% of the infiltrates show atypical lymphocytes, and the dermal vessels may show endothelial swelling, fibrin deposition and red blood cell extravasation. We are reporting a case of spontaneously healing CD56+ lymphomatoid papulosis, in the patient who received bone marrow transplantation, is reported.
Bone Marrow Transplantation
;
Bone Marrow*
;
Cicatrix
;
Eosinophils
;
Erythrocytes
;
Extremities
;
Fibrin
;
Forearm
;
Humans
;
Lymphocytes
;
Lymphomatoid Papulosis*
;
Neutrophils
;
Skin
;
Tissue Donors