1.Tooth color changes associated with the bracket bonding and debonding.
Seok Pil KIM ; In Nam HWANG ; Jin Hyoung CHO ; Hyeon Shik HWANG
Korean Journal of Orthodontics 2006;36(2):114-124
The purpose of this study was to evaluate the tooth color changes of resin bonding sites and their adjacent sites on orthodontic bracket bonding. Sixty extracted sound premolars were used and the tooth color was recorded according to the CIE L(*)a(*)b(*) color system using a spectrophotometer. The tooth colors of the twenty premolars were measured and compared before bracket bonding and after removal. On a further twenty premolars, the tooth color was measured before and after only primer application. In the change of L(*) values, according to the bracket bonding and primer application, the lightness was decreased, and in the change of a(*) and b(*) values, the color was changed into a more yellowish color. The color differences (delta E(*)) were calculated from the L(*)a(*)b(*) values and compared with the standard value of clinical detection (delta E(*)=3.7). The color differences between before the bracket bonding and after removal noted exceeded the standard value and those of between before and after the primer application were not larger than the standard value. Toothbrushing was performed after application of the primer to evaluate the color changes according to the primer abrasion. As a control, toothbrushing was performed on the last twenty premolars. The color differences noted were larger than the standard value after toothbrushing. Also, to evaluate the color changes of the tooth which is exposed to sun irradiation after bracket removal, additional photoaging was performed and the color was measured for all teeth. The additional color differences after photoaging were smaller than the standard value. The above results suggest that the tooth color changes after fixed orthodontic treatment.
Bicuspid
;
Orthodontic Brackets
;
Solar System
;
Tooth*
;
Toothbrushing
2.Experience of Transperitoneal Laparoscopic Adrenalectomy: lnitial 4 Cases.
Ahn Kie LEE ; Kwan Jin PARK ; Hyeon Hoe KIM ; Hwang CHOI
Korean Journal of Urology 2000;41(3):408-413
No abstract available.
Adrenalectomy*
3.Vascular Calcification in Chronic Kidney Disease: Distinct Features of Pathogenesis and Clinical Implication
Jin Sug KIM ; Hyeon Seok HWANG
Korean Circulation Journal 2021;51(12):961-982
Chronic kidney disease (CKD) is associated with a higher prevalence of vascular calcification (VC) and cardiovascular disease. VC in CKD patients showed different pathophysiological features from those of the general population. The pathogenesis of VC in CKD is a highly organized process, and prior studies have suggested that patients with CKD have their own specific contributors to the phenotypic change of vascular smooth muscle cells (VSMCs), including uremic toxins, CKD-mineral and bone disease (CKD-MBD), inflammation, and oxidative stress. For the diagnosis and monitoring of VC in CKD, several imaging modalities, including plain radiography, ultrasound, and computed tomography have been utilized. VC in CKD patients has distinct clinical features and implications. CKD patients revealed a more intense and more prevalent calcification on the intimal and medial layers, whereas intimal calcification is predominantly observed in the general population. While a higher VC score is clearly associated with a higher risk of all-cause mortality and cardiovascular events, a greater VC score in CKD patients does not fully reflect the burden of atherosclerosis, because they have more calcification at equal volumes of atheromatous plaques. The primary goal of VC treatment in CKD is the prevention of VC progression, and the main management is to control the biochemical components of CKD-MBD. Cinacalcet and non-calcium-containing phosphate binders are the mainstay of VC prevention in CKD-MBD management. VC in patients with CKD is an ongoing area of research and is expected to advance soon.
4.Breast hamartoma: 3 case report.
Ki Keun OH ; Hee Sung HWANG ; Choon Sik YOON ; Jin Sik MIN ; Kyong Sik LEE ; Hyeon Joo JEONG
Journal of the Korean Radiological Society 1991;27(1):77-81
No abstract available.
Breast*
;
Hamartoma*
5.Two Cases of Familial B-Thalassemia Minor.
Jeomg Hwa HWANG ; Hyeon Jeong LEE ; Jun HUR ; Gae Soon YEON ; Hee Jin KIM ; Tae Jun YUN ; Chan Yung KIM
Journal of the Korean Pediatric Society 1995;38(6):867-871
No abstract available.
6.Assessment of metal artifacts in three-dimensional dental surface models derived by cone-beam computed tomography.
Wael NABHA ; Young Min HONG ; Jin Hyoung CHO ; Hyeon Shik HWANG
The Korean Journal of Orthodontics 2014;44(5):229-235
OBJECTIVE: The aim of this study was to assess artifacts induced by metallic restorations in three-dimensional (3D) dental surface models derived by cone-beam computed tomography (CBCT). METHODS: Fifteen specimens, each with four extracted human premolars and molars embedded in a plaster block, were scanned by CBCT before and after the cavitated second premolars were restored with dental amalgam. Five consecutive surface models of each specimen were created according to increasing restoration size: no restoration (control) and small occlusal, large occlusal, disto-occlusal, and mesio-occluso-distal restorations. After registering each restored model with the control model, maximum linear discrepancy, area, and intensity of the artifacts were measured and compared. RESULTS: Artifacts developed mostly on the buccal and lingual surfaces. They occurred not only on the second premolar but also on the first premolar and first molar. The parametric values increased significantly with increasing restoration size. CONCLUSIONS: Metallic restorations induce considerable artifacts in 3D dental surface models. Artifact reduction should be taken into consideration for a proper diagnosis and treatment planning when using 3D surface model derived by CBCT in dentofacial deformity patients.
Artifacts*
;
Bicuspid
;
Cone-Beam Computed Tomography*
;
Dental Amalgam
;
Dentofacial Deformities
;
Diagnosis
;
Humans
;
Molar
7.Intussusception in an Adult due to Inverted Meckel's Diverticulum with Ectopic Pancreatic Tissue.
Ye Won JUN ; Bong Hyun KYE ; Hyung Jin KIM ; Hyeon Min CHO ; Changyoung YOO ; Seong Su HWANG
Journal of the Korean Surgical Society 2010;79(Suppl 1):S41-S44
Adult intussusception is rare involving of only 1% of the causes of bowel obstruction. We report a case of a 39-year-old female with intussusceptions due to inverted Meckel's diverticulum. She visited our hospital for diffuse abdominal pain during 1 week and aggravated abdominal pain for 2 days. Vital signs were stable, and there was periumbilical tenderness. She had no history of abdominal operation. CT scan showed a 3.7x2.1 cm of fatty mass with focal intussusception in the distal ileum. When the emergency operation was performed, the patient was found to be suffering from ileocolic intussusception. A manual reduction of intussusception showed inverted Meckel's deverticulum at 65 cm proximal to the ileocecal valve, and the segmental resection of small bowel including a Meckel's diverticulum was performed. Pathologic examination revealed a Meckel's diverticulum containing a 0.6x0.6 cm sized aberrant pancreas.
Abdominal Pain
;
Adult
;
Emergencies
;
Female
;
Humans
;
Ileocecal Valve
;
Ileum
;
Intussusception
;
Meckel Diverticulum
;
Pancreas
;
Stress, Psychological
;
Vital Signs
8.A comparative study of guiding methods for natural head posture in cephalometrics.
Jin Myoung SONG ; Ki Heon LEE ; Hyeon Shik HWANG
Korean Journal of Orthodontics 2005;35(5):341-350
The purpose of this study was to compare the degree of vertical head rotation and to evaluate the reproducibility of natural head posture (NHP) according to two guiding methods, the head posture aligner (HPA) method and the self balance posture (SBP) method. The subjects consisted of 30 adults. On the first day, lateral and frontal cephalometric radiographs were obtained through the two guiding methods. One month later, lateral and frontal cephalometric radiographs were obtained again through both guiding methods. The degrees of vertical head rotation of both guiding methods were compared and the reproducibility was evaluated for each guiding method. A comparison of the degrees of vertical head rotation for the two methods revealed that the vertical head posture was lower in the SBP method than in the HPA method by an average of 2.79 degrees. All measurements obtained using the HPA and SBP methods with a time interval of one month did not show any significant difference in lateral and frontal cephalometric radiographs. The results of the present study suggest that the SBP method may be used as an alternative to the HPA method in case the HPA method can not be applied.
Adult
;
Head*
;
Humans
;
Posture*
9.The effects of ipriflavone on the periodontal reorganization following experimental tooth movement in the rat.
Ji Hyun MIN ; Jin Hyoung CHO ; Ki Heon LEE ; Hyeon Shik HWANG
Korean Journal of Orthodontics 2008;38(5):347-357
OBJECTIVE: The purpose of this study was to examine the effect of ipriflavone on periodontal reorganization and prevention of relapse following tooth movement. METHODS: Orthodontic rubber bands were inserted between the first and second maxillary molars of 27 white male rats for 3 weeks for experimental tooth movement. From one day before the removal of orthodontic rubber band, ipriflavone was administered 50 or 400 mg/kg daily in each experimental group whereas carboxymethyl cellulose solution was administered in the control group. They were sacrificed at the 5, 10, and 15th day from the day of removal of orthodontic rubber bands. The amount of relapse was evaluated by measuring the interdental space, and the extent of periodontal reorganization was compared through histological examination. RESULTS: In case of ipriflavone administration, the amount and velocity of relapse was less and slower compared to the control group. In addition, the ipriflavone group showed more rapid periodontal reorganization compared to the control group. CONCLUSIONS: The results of the present study suggest that ipriflavone administration can be used effectively in the prevention of relapse following orthodontic tooth movement through the acceleration of periodontal reorganization.
Acceleration
;
Animals
;
Carboxymethylcellulose Sodium
;
Humans
;
Isoflavones
;
Male
;
Molar
;
Rats
;
Recurrence
;
Rubber
;
Tooth
;
Tooth Movement
10.Evaluation of cytotoxicity of electroplated stainless steel orthodontic wire.
Gye Hyeong LEE ; Jin Hyoung CHO ; Ki Heon LEE ; Hyeon Shik HWANG
Korean Journal of Orthodontics 2005;35(2):127-136
The purpose of this study was to examine the cytotoxicity of orthodontic wire which had an increased diameter through electroplating, and to evaluate its possible clinical applications. First, nickel plating was carried out on the commercially available stainless steel wire using an electroplating technique. For the comparison of the electroplated wire with ready made stainless steel wire and titanium or copper, each wire was incubated for 72 hours in a medium. The release of the metal ion was measured using ICP-AES (Inductively Coupled Plasma Atomic Emission Spectrophotometer). Balb/c 3T3 mouse fibroblast was put on a microplate and placed in an incubated medium of 75%, 50%, and 20% dilation. An MTT analysis was used to compare with the medium only. The change in absorbency value of each wire group and the difference of absorbency value according to the change of dilution was measured. The results of ICP-AES analysis showed that great amount nickel ion was isolated from electroplated orthodontic wires and great amount copper ion was isolated from copper. The results of the MTT analysis showed that there was no difference in the absorbency value of titanium at any dilution. However, the electroplated wires (p < 0.001), the stainless steel wires (p < 0.05) and the copper (p < 0.001) were statistically significantly lower than those of medium only at all dilutions. Assessment as per ISO 10993, part 5, showed that electroplated wire was alloted to "moderate cytotoxic", the titanium and stainless steel wire were "non-cytotoxic". The results of this study indicate that the electroplated orthodontic wires need additional efforts to decrease cytotoxicity for their clinical applications.
Animals
;
Copper
;
Electroplating
;
Fibroblasts
;
Mice
;
Nickel
;
Orthodontic Wires*
;
Plasma
;
Stainless Steel*
;
Titanium