1.The level of residual monomer in injection molded denture base materials.
Hyeok Jae LEE ; Chang Whe KIM ; Yung Soo KIM
The Journal of Korean Academy of Prosthodontics 2003;41(3):360-368
STATEMENT OF PROBLEM: The residual monomer of denture base materials causes hypersensitivity on oral mucosa and intereferes with the mechanical properties of the cured resin. The amount of residual monomer is influenced by materials, curing cycle, processing method, and etc. PURPOSE: The aim of this study was to investigate the residual methyl methacrylate(MMA) content of injection molded denture base polymer, and to compare this with the self-cured resin and the conventional compression molded heat-cured resin. MATERIALS AND METHODS: Disc shaped test specimens (50mm in diameter and 3mm thick) were prepared in a conventional flasking technique with gypsum molding. One autopolymerized denture base resins (Vertex SC. Dentimex. Netherlands) and two heat-cured denture base resins (Vertex RS. Dentimex. Netherlands, Ivocap. Ivoclar Vivadent, USA) were used. The three types of specimens were processed according to the manufacturer's instruction. After polymerization, all specimens were stored in the dark at room emperature for 7 days. There were 10 specimens in each of the test groups. 3-mm twist drills were used to obtain the resin samples and 650mg of the drilled sample were collected for each estimation. Gas chromatography (Agillent 6890 Plus Gas Chromatograph, Agillent Co, USA) was used to determine the residual MMA content of 10 test specimens of each three types of polymer. RESULTS: The residual monomer content of injection molded denture base resins was 1.057+/- 0.141%. The residual monomer content of injection molded denture base resins was higher than that of compression molded heat cured resin (0.867+/-0.169%). However, there was no statistical significant difference between two groups (p > 0.01). The level of residual monomer in self cured resin(3.675+/-0.791) was higher than those of injection molded and compression molded heat cured resins (p<0.01). CONCLUSION: With respect to ISO specification pass/fail test (2.2% mass fraction) of residual monomer, injection molding technique(1.057+/-0.141%) is a clinicaly useful and safe technique in terms of residual monomer.
Calcium Sulfate
;
Chromatography, Gas
;
Denture Bases*
;
Dentures*
;
Fungi*
;
Hot Temperature
;
Hypersensitivity
;
Mouth Mucosa
;
Netherlands
;
Polymerization
;
Polymers
2.Complications of Traumatic Brain Injury: Post-traumatic Headache and Epilepsy.
Brain & Neurorehabilitation 2012;5(2):62-67
Posttraumatic headache (PTH) is one of several complications of traumatic brain injury (TBI). PTH usually resolving within the first 3 months, although a minority develop chronic headaches. PTH remains among the most controversial headache topics to its propensity for chronicity and often associated additional cognitive, behavioral, and somatic problems. Sufficient psychological or neurobiological markers for PTH do no exist, thus treatment can be very challenging and should always be multidisciplinary to make every reasonable effort in preventing the development of chronic pain. Posttraumatic seizure or epilepsy (PTE) is defined as a recurrent seizure disorder due to traumatic brain injury. PTE can be divided into three groups: immediate, early and late seizures. Immediate and early seizures are provoked seizures, whereas late seizure is unprovoked seizure. The effects of antiepileptic drugs (AED) in patients with TBI must be assessed separately in terms of prevention and control of provoked seizures and prevention of subsequent unprovoked seizures. Routine preventive AEDs are not indicated for patients with TBI and the effects are controversy.
Anticonvulsants
;
Brain
;
Brain Injuries
;
Chronic Pain
;
Epilepsy
;
Headache
;
Headache Disorders
;
Humans
;
Post-Traumatic Headache
;
Seizures
3.Accuracy of a proposed implant impression technique using abutments and metal framework.
Hyeok Jae LEE ; Young Jun LIM ; Chang Whe KIM ; Jung Han CHOI ; Myung Joo KIM
The Journal of Advanced Prosthodontics 2010;2(1):25-31
PURPOSE: This study compared the accuracy of an abutment-framework (A-F) taken with open tray impression technique combining cementon crown abutments, a metal framework and resin cement to closed tray and resin-splinted open tray impression techniques for the 3-implant definitive casts. The effect of angulation on the accuracy of these 3 techniques was also evaluated. MATERIAL AND METHODS: Three definitive casts, each with 3 linearly positioned implant analogs at relative angulations 0, 30, and 40 degrees, were fabricated with passively fitted corresponding reference frameworks. Ten impressions were made and poured, using each of the 3 techniques on each of the 3 definitive casts. To record the vertical gap between reference frameworks and analogs in duplicate casts, a light microscope with image processing was used. Data were analyzed by two-way analysis of variance and the Tukey test. RESULTS: The open tray techniques showed significantly smaller vertical gaps compare to closed tray technique (P < .05). The closed tray and the resin-splinted open tray technique showed significantly different vertical gaps according to the angulation of implant (P < .05), but the A-F impression technique did not (P > .05). CONCLUSION: The accuracy of the A-F impression technique was superior to that of conventional techniques, and was not affected by the angulation of the implants.
Crowns
;
Light
;
Resin Cements
4.Recombination and Expression of VP1 Gene of Infectious Pancreatic Necrosis Virus DRT Strain in a Baculovirus,Hyphantria cunea Nuclear Polyhedrosis Virus.
Hyung Hoan LEE ; Jae Hyeok CHANG ; Hye Kyung CHUNG ; Sung Chul CHA
Journal of the Korean Society of Virology 1997;27(2):239-256
Expression of the cDNA of the VP1 gene on the genome RNA B segment of infectious pancreatic necrosis virus (IPNV) DRT strain in E. coli and a recombinant baculovirus were carried out. The VP1 gene in the peal-pol clone (Lee et al 1995) was cleaved with XbaI and transferred into baculovirus transfer vector, pBacPAK9 and it was named pBacVP1 clone. The VP1 gene in the pBacVP1 clone was double-digested with SacI and PstI and then inserted just behind 75 phage promoter and the 6x His region of the pQE-30 expression vector, and it was called pQEVP1. Again, the 6xHis-tagged VP1 DNA fragment in the pOEVPl was cleaved with EcoRl and transferred into the VP1 site of the pBacVPl, resulting pBacHis-VPl recombinant. The pBacHis-VP1 DNA was cotransfected with LacZ-Hyphantria cunea nuclear polyhedrosis virus (Lacz-HcNPV) DNA digested with Bsu361 onto S. frugiperda cells to make a recombinant virus. One VP1-gene inserted recombinant virus was selected by plaque assay, The recombinant virus was named VP1-HcNPV-1. The 6xHis-tagged VP1 protein produced by the pQEVPl was purified with Ni-NTA resin chromatography and analyzed by SDS-PAGE and Western blot analysis. The molecular weight of the VP1 protein was 94 kDa. The recombinant virus, VP1-HcNPV-1 did not form polyhedral inclusion bodies and expressed VP1 protein with 95 kDa in the infected S. frugiperda cells, which was detected by Western blot. The titer of the VP1-HcNPV-1 in the first infected cells was 2.0x10(5) pfu/ml at 7 days postinfection.
Bacteriophages
;
Baculoviridae
;
Blotting, Western
;
Chromatography
;
Clone Cells
;
DNA
;
DNA, Complementary
;
Electrophoresis, Polyacrylamide Gel
;
Genome
;
Inclusion Bodies
;
Infectious pancreatic necrosis virus*
;
Molecular Weight
;
Nucleopolyhedrovirus*
;
Recombination, Genetic*
;
RNA
5.Motor Recovery Effect of Minocycline in Spinal Cord Injured Rats.
Hyun Yoon KO ; Jae Hyeok CHANG ; Jae Heung PARK
Journal of the Korean Academy of Rehabilitation Medicine 2006;30(6):565-570
OBJECTIVE: To observe motor recovery after spinal cord injury (SCI) by time and impact strength in minocycline administration rat. METHOD: Forty Sprague-Dawley rats were divided into four groups according to minocycline administration and damage heights. Rats in first group were damaged in 2.5 cm heights, and injected with minocycline. In second group, minocycline was not injected. Rats in third group were damaged in 5 cm heights, and injected with minocycline. In fourth group, rats were damaged in 5 cm and minocycline was not injected. Rats received injury by the force-calibrated weight drop device and first and third groups injected minocycline 90 mg/kg immediately after injury and injected 45 mg/kg every 12 hours. Motor recovery was determined by the Basso-Beattie-Bresnahan (BBB) locomotor rating scale at 1st, 7th, 14th, 21st, and 28th day after injury. RESULTS: The BBB scores were significantly higher in first and third groups as compared to second and fourth groups after injury. There was significant change of BBB scores in first group as compared to third. CONCLUSION: After injury, BBB scores were significantly higher in minocycline treated rats as compared to the control. Minocycline might have beneficial effects on the recovery cascade after SCI.
Animals
;
Minocycline*
;
Rats*
;
Rats, Sprague-Dawley
;
Spinal Cord Injuries
;
Spinal Cord*
6.Secondary Parkinsonism due to Extrapontine Myelinolysis without Central Pontine Myelinolysis: A case report.
Jae Heung PARK ; Jae Hyeok CHANG ; Ji Sang PARK ; Si Chul CHO
Journal of the Korean Academy of Rehabilitation Medicine 2007;31(1):119-112
Parkinsonism is characterized by clinical symptoms of rigidity, bradykinesia, tremor, and gait disturbance. There are many causes of secondary parkinsonism. The present report discusses a secondary parkinsonism of extrapontine myelinolysis (EPM) without central pontine myelinolysis (CPM) after rapid correction of hyponatremia. EPM is a demyelinating process of the brain. EPM with CPM is relatively common, but EMP without CPM is rare. A 57- year-old woman with Tsutsugamushi disease had a subacuteonset of parkinsonism on the fourteenth day after a rapid correction of severe hyponatremia. Magnetic resonance imaging of the bilateral basal ganglia showed a high signal intensity on T2-weighted images, and a low signal on T1- weighted images. She was started on levodopa, and parkinsonian features slowly improved. We report an unusual case of EPM without CPM, that presented with parkinsonism.
Basal Ganglia
;
Brain
;
Female
;
Gait
;
Humans
;
Hypokinesia
;
Hyponatremia
;
Levodopa
;
Magnetic Resonance Imaging
;
Myelinolysis, Central Pontine*
;
Parkinson Disease, Secondary*
;
Parkinsonian Disorders
;
Scrub Typhus
;
Tremor
7.Effects of Botulinum Toxin on Reducing the Co-contraction of Antagonists in Birth Brachial Plexus Palsy.
Yong Beom SHIN ; Myung Jun SHIN ; Jae Hyeok CHANG ; Young Sun CHA ; Hyun Yoon KO
Annals of Rehabilitation Medicine 2014;38(1):127-131
Birth brachial plexus palsy (BBPP) is usually caused by plexus traction during difficult delivery. Although the possibility of complete recovery is relatively high, 5% to 25% of BBPP cases result in prolonged and persistent disability. In particular, muscle imbalance and co-contraction around the shoulder and elbow cause abnormal motor performance, osseous deformities, and joint contracture. Physical and occupational therapies have most commonly been used, but these conventional therapeutic strategies have often been inadequate, in managing the residual muscle imbalance and muscle co-contraction. Therefore, we attempted to improve the functional movements, by using botulinum toxin type A, to reduce the abnormal co-contraction of the antagonist muscles.
Botulinum Toxins*
;
Botulinum Toxins, Type A
;
Brachial Plexus Neuropathies
;
Brachial Plexus*
;
Congenital Abnormalities
;
Contracture
;
Elbow
;
Joints
;
Muscles
;
Occupational Therapy
;
Paralysis*
;
Parturition*
;
Shoulder
;
Traction
8.Airway Inflammation and Responses in the Bronchial Asthma Model in Sprague-Dawley Rats Sensitized by Ovalbumin.
Moon Jun NA ; Byoung Hoon LEE ; Chang Hyeok AN ; Jae Yeol KIM ; In Won PARK ; Byung Whui CHOI ; Sung Ho HUE
Tuberculosis and Respiratory Diseases 2000;48(1):33-44
BACKGROUND: To evaluate airway responses and inflammation to antigen in Sprague-Dawley rat asthma model, we examined airway responses, serial histologic changes of the lung, and the relationship between airway responses and airway inflammation after antigen airway challenge. METHODS: Sprague-Dawley rats were sensitized with subcutaneous injection of 10 microgram ovalbumin(OA). Antigen airway challenges were done 14 ~16 days after sensitization and the sensitized rats were sacrificed 1h(AE), 6 ~8h(AL) and 1day(AD) after airway challenge, to examine the histologic changes of the lung. Airway responses were measured by body plethysmograph and recorded by enhanced pause(Penh) as an index of airway obstruction 6 ~8h after antigen challenges. Nonsensitized controls(10 rats) were also challenged with antigen and sacrificed 1 day later. Histopathologic examination of two trachea, large bronchi, small bronchi, and vessels was performed to evaluate the severity of inflammation and eosinophilic infiltration with H&E stain. RESULTS: In 17 of 20 rats(85%) in both groups, we observed airway responses. Among them, an early response(ER) in 15 rats(75%), an dual response in 5(25%), and an late response(LR) only in 2 rats(10%) displayed. There were no significant differences in the severity of inflammation among the trachea, large bronchi, small bronchi and vessels in all groups after antigen challenge(p>0.05) and between early and late responders. The significant eosinophil infiltration was observed in 5 rats(50%) of AL(p<0.05) compared with in AE and controls. Also, eosinophil infiltration was observed in higher trend in LR(57.1%) compared to ER(40%)(p>0.05). CONCLUSION: Sprague-Dawley rats sensitized with subcutaneous injection of OA showed a significant airway responses to antigen challenge. But antigen challenges caused a little eosinophil infiltration and no significant airway inflammation. Asthma model of Sprague-Dawley rats could be useful for antigen-induced airway responses, but this model has a limitation for the study of human asthma because of no significant pathologic change.
Airway Obstruction
;
Animals
;
Asthma*
;
Bronchi
;
Eosinophils
;
Humans
;
Inflammation*
;
Injections, Subcutaneous
;
Lung
;
Ovalbumin*
;
Rats
;
Rats, Sprague-Dawley*
;
Trachea
9.Leadpoints in Childhood Intussusception.
Kwan Ju LEE ; Jae Hee CHUNG ; Min Kwang HONG ; Won Yong SUNG ; Chang Hyeok AN ; Young Tack SONG
Journal of the Korean Association of Pediatric Surgeons 2001;7(2):126-129
Childhood intussusception is usually idiopathic, and pathological lesions as the leading point are found in limited cases. Sixteen operative cases with leadpoints among 2,889 cases of childhood intussusecption treated at the surgical departments of the affiliated hospitals of Catholic University over 19 years are reviewed. The approximate incidence of pathological lesions as the leading point was 0.6%. The male to female ratio was 2:1. The mean age was 3.5 years. There was not an age preponderance. The symptoms were vomiting (63%), abdominal pain (38%), irritability (38%), bloody stools (25%), fever (25%) and abdominal mass (6%). The average duration of the symptoms was 2.4 days (1-10days). The most common lesion was Meckel's diverticulum, followed by malignant lymphomas, polyps, ectopic pancreas, and cecal duplication. An ileocolic type was most frequent, followed by ileoileocolic and ileoileal. Segmental resection or wedge resection of the ileum was done in 10 cases, ileocecectomy in 3, and right hemicolectomy in 3. Surgical reduction was done only in an ectopic pancreas, with no later recurrence. The average hospital stay was 10 days. Postoperative adhesive ileus occurred in two cases, and in one of them adhesiolysis was performed. One case of malignant lymphoma died at 28 days after surgery due to chemotherapy related complication.
Abdominal Pain
;
Adhesives
;
Drug Therapy
;
Female
;
Fever
;
Humans
;
Ileum
;
Ileus
;
Incidence
;
Intussusception*
;
Length of Stay
;
Lymphoma
;
Male
;
Meckel Diverticulum
;
Pancreas
;
Polyps
;
Recurrence
;
Vomiting
10.A Case of Annular Pustular Psoriasis Showing Features of Subcorneal Pustular Dermatosis.
Hyeok Man KWON ; Jeong Soo KIM ; Young Suck RO ; Chang Woo LEE ; Jae Hong KIM
Korean Journal of Dermatology 2002;40(12):1527-1530
Annular pustular psoriasis(APP) is a rare variant of the generalized pustular psoriasis characterized by subacute onset of annular lesion with peripheral advancing pustules. Histologically, it is characterized by spongiform and/or subcorneal pustules which are also found in subcorneal pustular dermatosis(SPD). SPD is very difficult to differentiate from APP, although SPD is thought to be a separate and distinctive entity because of its clinical appearance, characteristic histology, and response to dapsone. We herein report a case of APP showing clinical and histologic features of SPD developed in a patient who had a history of generalized pustular psoriasis.
Dapsone
;
Humans
;
Psoriasis*
;
Skin Diseases, Vesiculobullous*