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.Statitical Techniques Reported in Korean Dermatology Journals During 1990-1994.
Sung Yul LEE ; Jong Suk LEE ; Jae Young HWANG ; Chong Hyeok KIM
Annals of Dermatology 1996;8(4):243-246
BACKGROUND: Effective evaluation of an article's scientific merit requires familiarity with the methodology described, especially when quantitative techniques, such as statistical procedures, are invoked to clarify research findings or to summarize data. OBJECTIVE: The purpose of this study was to describe the frequency with which various statistical concepts were reported in journals important to dermatology. From these results, dermatologists can identify the major statistical skills needed to critically evaluate their literature. METHODS: All 376 original articles of the Korean Journal of Dermatology(KJD) and the Annals of Dermatology(KAD) during 1990-1994 were chosen for review. Each article was re-viewed to determine the statistical content. RESULTS: The two most commonly used statistical techniques in the two journals were mean and standard deviation. The t-test was the next most frequently used statistical technique in the reviewed journals, followed by non-parametric, chi-square test, orphan p, ANOVA, and correlation/regression. CONCLUSION: These results indicate the need for wider education about the use of descriptive and basic comparative statistics. It is impossible to evaluate the dermatological literature critically without these skills.
Child
;
Child, Orphaned
;
Dermatology*
;
Education
;
Humans
;
Recognition (Psychology)
3.Acanthocytosis in a Patient with Chorea-acanthocytosis.
Laboratory Medicine Online 2012;2(3):179-180
No abstract available.
Abetalipoproteinemia
;
Humans
;
Neuroacanthocytosis
4.Acanthocytosis in a Patient with Chorea-acanthocytosis.
Laboratory Medicine Online 2012;2(3):179-180
No abstract available.
Abetalipoproteinemia
;
Humans
;
Neuroacanthocytosis
5.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
6.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
7.Neuropsychological profiles and their correlation to motor symptoms in newly diagnosed Parkinsondisease patients with mild cognitive impairment
Eun Joo Chung ; Jae-Hyeok Lee ; Kyngha Seok ; Sang Jin Kim
Neurology Asia 2014;19(1):19-25
Background & Objectives: Frontal executive dysfunction, which is hypothesized to reflect dorsolateral
prefrontal function, predominates in Parkinson’s disease (PD). Visuospatial dysfunction and episodic
memory deficit, which are associated with the posterior cortical area, are critical symptoms of mild
cognitive impairment in PD (PD-MCI). The first aim of this study is to investigate whether dominant
cognitive deficits are caused by posterior cortical dysfunction in drug naïve, de novo PD-MCI patients.
The second aim is to analyze the relationship between parkinsonian motor symptoms and the cognitive
domain in these patients. Methods: Newly diagnosed PD patients who had not received treatment were
divided into two subgroups as follows: PD-MCI (n=39) and PD patients with normal cognition (PD-NC)
(n=39). Various neuropsychological tests were performed in all of the patients. The parkinsonian motor
subscores were divided into tremor, rigidity, axial impairment, bulbar dysfunction and bradykinesia
by the UPDRS motor scores. Results: Verbal episodic memory (immediate recall; p = 0.0001, delayed
recall; p = 0.0001, recognition; p = 0.003), visual episodic memory (immediate recall; p = 0.0001,
delayed recall; p = 0.002) and visuospatial function (p = 0.046) were lower in the PD-MCI group
than in the PD-NC group. In the analysis of the correlation of the motor components to the cognitive
tests, impairment in visual episodic memory correlated with axial symptoms (immediate recall; r =
-0.441, p = 0.021, delayed recall; r = -0.393, p = 0.042). The contrast program test correlated with
bradykinesia (r = -0.479, p = 0.013)
Conclusion: Episodic memory and visuospatial dysfunction, which reflect impairment of the posterior
cortical area, are critical cognitive deficits, and memory impairment is correlated with the axial symptoms
that are associated with non-dopaminergic pathways in newly diagnosed PD-MCI patients.
8.Behavioral and psychological symptoms in Korean patients with mild Alzheimer’s disease: Preliminary study
Soo-Ji Lee ; Jae-Hyeok Heo ; Hee-Tae Kim ; Jin-Young Ahn
Neurology Asia 2013;18(1):65-71
Behavioral and psychological symptoms of dementia are major components of Alzheimer’s disease.
In this study, we aimed at investigating the prevalence and severity of behavioral and psychological
symptoms of dementia in very mild to mild Alzheimer’s disease. Forty-four patients with Alzheimer’s
disease who visited the neurology outpatient clinic of Seoul Medical Center were included. A trained
neurologist or a supervised test technician administered the neuropsychological test, the Seoul
Neuropsychological Screening Battery including Mini Mental State Examination and Clinical Dementia
Rating. The instrument used for assessing behavioral and psychological symptoms of dementia was
Neuropsychiatric Inventory-Questionnaire. In order of prevalence, apathy, depression, irritability,
anxiety, and agitation were the most common symptoms occurring in very mild-to-mild Alzheimer’s
disease group. The prevalence and severity of behavioral and psychological symptoms of dementia
were found to be in positive correlation with the Clinical Dementia Rating scores. Behavioral and
psychological symptoms of dementia are found even in the very early stage of Alzheimer’s disease,
apathy and depression being the most common symptoms. Physicians should be aware of this when
managing dementia patients.
9.Arthroscopic Synovectomy in the Rheumatoid Arthritis of the Knee Joint.
Hyun Kee CHUNG ; Choong Hyeok CHOI ; Young Joon CHOI ; Kyeong Jin CHOI ; Jae Min LEE
The Journal of the Korean Orthopaedic Association 1998;33(2):264-272
The short term beneficial effect of arthroscopic excision of synovial tissue in knees with rheumatoid arthritis have been well documented. The purpose of this study to report the results of synovectomy in patients with rheumatoid arthritis who have been observed at least 3 years. We analysed the clinical result with modified Laurin criteria, radiologic change and patients own satisfaction degree with survey. The results were as follows; 1. The preoperative symptoms were pain (100%), swelling (100%), decreased range of motion (83%) and joint tenderness (74%), and those were improved postoperatively to 43%, 60%, 11%, 43% each other. 2. Among the laboratory parameters, C-reactive protein (CRP) was improved most significantly (pvalue =0.026). 3. On simple supine A-P X-rays, the width of medial joint space and lateral joint space were compared to preoperatively and postoperatively. The width of medial joint space was 4.33mm preoperatively, and it was changed to 3.22mm at last follow up (p=0.032). Those of lateral joint space was changed from 4.24mm preoperatively to 3.27mm at last tollow up (p=0.106). 4. The grade of articular cartilage damage was related with severity of preoperative symptoms and the patients with low grade of articular cartilage damage showed more postoperative improvement. The result of operation was related to symptom duration, degree of X-ray change and degree of cartilage damage. 5. 58% ot patients were satisfied to results of synovectomy, 28% were answered neither satisfied nor ansatisfied and 14% were unsatisf'ied to operation. We concluded the arthroscopic synovectomy of the knee joints was effective procedure to improve the clinical symptoms, range of knee motion and to alleviate the inflammatory reaction at mid-term period al'ter the operation. So we consider this procedure is a palliative treatment that modified and alleviate the progression of rheumatoid arthritis of knee joints.
Arthritis, Rheumatoid*
;
C-Reactive Protein
;
Cartilage
;
Cartilage, Articular
;
Follow-Up Studies
;
Humans
;
Joints
;
Knee Joint*
;
Knee*
;
Palliative Care
;
Range of Motion, Articular
10.Recurrent Aspiration Pneumonia due to Anterior Cervical Osteophyte.
Jae Jun LEE ; Ji Young HONG ; Jun Han JUNG ; Jun Hyeok YANG ; Jun Young SOHN
Korean Journal of Critical Care Medicine 2017;32(1):74-78
A 74-year-old man presented with recurrent vomiting and aspiration pneumonia in the left lower lobe. He entered the intensive care unit to manage the pneumonia and septic shock. Although a percutaneous endoscopic gastrostomy tube was implanted for recurrent vomiting, vomiting and aspiration recurred frequently during admission. Subsequently, he complained of neck pain when in an upright position. A videofluoroscopic swallowing study showed compression of the esophagus by cervical osteophytes and tracheal aspiration caused by an abnormality at the laryngeal inlet. Cervical spine X-rays and computed tomography showed anterior cervical osteophytes at the C3-6 levels. Surgical decompression was scheduled, but was cancelled due to his frailty. Unfortunately, further recurrent vomiting and aspiration resulted in respiratory arrest leading to hypoxic brain damage and death. Physicians should consider cervical spine disease, such as diffuse skeletal hyperostosis as an uncommon cause of recurrent aspiration pneumonia.
Aged
;
Bays
;
Decompression, Surgical
;
Deglutition
;
Esophagus
;
Gastrostomy
;
Humans
;
Hyperostosis
;
Hypoxia, Brain
;
Intensive Care Units
;
Neck Pain
;
Osteophyte*
;
Pneumonia
;
Pneumonia, Aspiration*
;
Shock, Septic
;
Spine
;
Vomiting