1.COMPARISON OF WEAR RESISTANCE AMONG RESIN DENTURE TEETH OPPOSING VARIOUS RESTORATIVE MATERIALS.
Chul Young LEE ; Moon Kyu CHUNG
The Journal of Korean Academy of Prosthodontics 1999;37(3):313-327
The aim of this study was to compare wear resistance of resin denture teeth opposing various restorative materials. The wear resistance of conventional acrylic resin teeth (Trubyte Biotone) and three high-strength resin teeth(Bioform IPN, Endura, SR-Orthosit-PE) opposing different restorative materials (gold alloys, dental porcelain, composite resin) was compared. Wear tests were conducted with a sliding-induced wear testing apparatus which applied 100,000 strokes to the specimen in an mesio-distal direction under conditions of 100 stroke/min and constant loading of 1Kgf/tooth. Wear resistance of the resin denture teeth was evaluated by the following criteria : 1) wear depth, 2)weight loss, and 3) SEM observation. Results were as follows. 1. When opposed to gold alloys and composite resin, high-strength resin teeth showed superior wear resistance compared to acrylic resin teeth. But, in cases opposing dental porcelain, differences between the wear of the high-strength and acrylic resin teeth were not statistically significant (p<0.05). 2. When comparing wear resistance among high-strength resin teeth, opposing gold alloys, Endura was slightly more resistant and while in cases opposing dental porcelain, SR-Orthosit-PE was showed to be slightly resistant(p<0.05). 3. The wear of high-strength resin teeth was greater by 5 to 7 times when opposing porcelain and 2 to 3 times when opposing composite resin compared to gold alloys(p<0.05). 4. SEM observations of the wear surface showed that wear of resin teeth opposing gold alloys is a fatigue type of wear and wear of resin teeth opposing dental porcelain is fatigue and abrasion type of wear. Trubyte Biotone showed more severe fatigue type of wear than high-strength resin teeth. In conclusion, the use of dental porcelain should seriously be considered as restorative material in cases opposing resin denture teeth and improvement seems to be needed on resin teeth in the areas of wear resistance.
Dental Alloys
;
Dental Porcelain
;
Dentures*
;
Fatigue
;
Gold Alloys
;
Stroke
;
Tooth*
2.Prefrontal Cortex and Schizophrenia.
Young Chul CHUNG ; Hong Bae EUN
Journal of the Korean Society of Biological Psychiatry 1998;5(2):184-196
With a rapid development of neuroscience, the theories related to the pathophysiology of schizophrenia have been changed a lot from a simple hyperdopaminergic one to the various complicated ones. Among these, the theories regarding prefrontal cortex(PFC) pathology as a cause of schizophrenia are gaining more recognition as the results of neuroimaging and neuropsychological tests in schizophrenia consistently report abnormalities in PFC. Therefore, we first reviewed the unique characteristics of PFC in anatomy, neurochemistry and neurophysiology to enhance an understanding of those ones. Secondly, various neurotransmitter, neurodevelopmental and neural network theories of schizophrenia introduced recently were reviewed in terms of PFC pathology.
Dopamine
;
Neurochemistry
;
Neuroimaging
;
Neurophysiology
;
Neuropsychological Tests
;
Neurosciences
;
Neurotransmitter Agents
;
Pathology
;
Prefrontal Cortex*
;
Schizophrenia*
3.A case of amniotic band syndrome with anencephaly.
Young Chul YOO ; Chung Hoon KIM ; Soon Beom KANG
Korean Journal of Obstetrics and Gynecology 1991;34(5):705-710
No abstract available.
Amniotic Band Syndrome*
;
Anencephaly*
;
Infant, Newborn
4.Two cases of atypical fibroxanthoma of the skin.
Young Jo KIM ; Byoung Soo CHUNG ; Kyu Chul CHOI
Korean Journal of Dermatology 1992;30(5):715-719
Atypical fibroxanthoma(AFX) occurs most on sun-exposed area of the head and neck of elderly person. It has an excellent prognosis after conservative, but complete, excision. However, because of its potential, albeit small, for metastasis, it is widely regarded as a low-grade sarcoma. We present herein two cases of atypical fibroxanthoma. The case 1 was a 86-year-old female who had a small egg-sized, dome shaped nodule with eroive surface on the left cheek. The other case was a 60-year-old male who had solitry bean-sized, nodulo-ulcerative lesion on the vertex. Immunohistochemical studies revealed positive reaction for vimntin and a-antichymo trypsin. These patients have received completely total surgical ecis on and remained free of recurrence for a period of about, 2 years follow up.
Aged
;
Aged, 80 and over
;
Cheek
;
Female
;
Follow-Up Studies
;
Head
;
Humans
;
Male
;
Middle Aged
;
Neck
;
Neoplasm Metastasis
;
Prognosis
;
Recurrence
;
Sarcoma
;
Skin*
;
Trypsin
5.Prevalence and clinical characteristics of the anti-HCV positive patients who had invreased transaminase levels with negative HBsAg.
Eun Joo AHN ; Tae Ho CHUNG ; Hee Chul KANG ; Chul Young BAE ; Dong Hak SHIN
Journal of the Korean Academy of Family Medicine 1992;13(1):72-78
No abstract available.
Hepatitis B Surface Antigens*
;
Humans
;
Prevalence*
6.A study on relationship of headache to depression and anxiety.
Tae Ho CHUNG ; Young Sung SUH ; Su Young LIM ; Hi Chul KANG ; Chul Young BAE ; Dong Hak SHIN
Journal of the Korean Academy of Family Medicine 1992;13(5):436-441
No abstract available.
Anxiety*
;
Depression*
;
Headache*
7.Bacterial meningitis in newborn and infant: Correlation between organism, CT findings and clinical outcome.
Hye Young CHOI ; Young Seo PARK ; Shi Joon YOO ; Dae Chul SUH ; Young Kyo CHUNG
Journal of the Korean Radiological Society 1993;29(2):312-318
Bacterial meningitis results in significant neurologic dificits despite in spite of much effort in the treatment of the disease. This study was performed to determine the incidence of caustive organisms and to correlate between the organisms and computed tomographic (CT) findings with clinical outcome of bacterial meningitis in newborns and infants. We analyzed the brain CT and clinical records of 15 infants who had been diagnosed as bactrial meningitis by CSF culture. We found that the most common organisms were Group B streptococcus in neonates withou no neurologic complications in all but one and Hemophilus influenza in infants whose clinical outomes were poor in all except one. CT findings related with poor prognosis in this study were cerebral edema, basal cistermal obliteration & enhancement, and cerebral infarction on initial CT and ventriculomegaly on follow-up CT. We concluded that CT diagnosed intracranial complications of bacterial meningitis well and could contributed to better treatment of bacterial meningitis.
Brain
;
Brain Edema
;
Cerebral Infarction
;
Follow-Up Studies
;
Haemophilus
;
Humans
;
Incidence
;
Infant*
;
Infant, Newborn*
;
Influenza, Human
;
Meningitis
;
Meningitis, Bacterial*
;
Prognosis
;
Streptococcus
8.Effect of MK-801 on the Prevention and Treatment of Tardive Dyskinesia.
Jeung Soo SEO ; Young Chul CHUNG ; Keun Young PARK ; Hong Bai EUN ; Young Hyun KIM
Journal of the Korean Society of Biological Psychiatry 1997;4(2):246-250
Tardive dyskinesia(TD) is a serious side effect of long-term treatment with neuroleptic medications. To investigate if glutamatergic hyperfunction is associated with TD, effect of MK-801 on the prevention and treatment of TD was studied using a rat model, i.e., vacuous chewing movements(VCM). When comparing VCM scores of Group I(haldol decanoate+MK-801) with that of Group II(hadol decanoate+phosphate buffer saline), late measured VCM scores of former were significantly lower than that of latter, meaning that MK-801 is effective in the prevention of VCM. Furthermore, when MK-801 is also effective in the treatment of VCM. From the above results, it is suggested that glutamatergic hyperfunction might be involved in the development of TD and MK801 could be effective in the prevention and treatment of it.
Dizocilpine Maleate*
;
Mastication
;
Models, Animal
;
Movement Disorders*
9.Short Term Chemotherapy in Urinary Tuberculosis.
Chung Sub JUNG ; Woo Chul MOON ; Young Sun KIM
Korean Journal of Urology 1989;30(5):727-733
Recently short term chemotherapy has become popular for the treatment of genitourinary tuberculosis. But it is questionable weather short term chemotherapy can cure all cases of genitourinary tuberculosis regardless of their severity ;and the role of nephrectomy in patients with renal tuberculosis is still controversial. Herein we analyzed 52 patients with confirmed urinary tuberculosis who were treated with triple drugs, including isoniazid, rifampicin and ethambutol, for 6 to 9 months. The patients ranged from 13 to 71 years of age, and the male to female ratio was 2.4: 1. Follow up period ranged from 6 to 65 months with a mean period of 19.7 months. The patients were classified according to the severity of renal tuberculosis on pyelography into Group I ( minimal, 8 patients), II (moderate, 9 patients) and III (severe, 35 patients), and treatment result were analyzed in each group. Of 52 patients, 19 were treated by chemotherapy only and 33 (63.5%) reconstructive surgery. Success rates of short term chemotherapy in terms of cure of tuberculosis and preservation of functional renal tissue were :overall 75%, 100% in Group I , 77% in Group II and 68.6% in Group III. Two of 9 patients in Group II and 10 of 17 in Group III who were treated with chemotherapy only, deteriorated with loss of the kidney. Poor vascular pyonephrotic kidney and progressive ureteral stricture were suggested as the main cause of failure. Ureteroneocystostomy and double J enting were helpful not only in the preservation of the kidney but also in the rapid cure of a renal tuberculosis. 24 patients who were treated with 6 to 9 months chemotherapy after removal of their nonfunctioning kidney were relapse-free on follow up. In conclusion, 6 to 9 months chemotherapy is adequate minimal urinary tuberculosis. For the treatment of moderate to advanced urinary tuberculosis, a longer period of chemotherapy may be adequate, and meticulous follow up with IVP and aggressive management of ureteral stricture is essential. A far advanced, nonfunctioning, unilateral tuberculosis kidney is better to be removed early, followed by 6 to 9 months' chemotherapy.
Constriction, Pathologic
;
Drug Therapy*
;
Ethambutol
;
Female
;
Follow-Up Studies
;
Humans
;
Isoniazid
;
Kidney
;
Male
;
Nephrectomy
;
Rifampin
;
Tuberculosis*
;
Tuberculosis, Renal
;
Ureter
;
Urography
;
Weather
10.Multiple ESWL treatment for renal stones with piezoelectric lithotriptor.
Young Tae MOON ; Chung Hwan OH ; Sae Chul KIM
Korean Journal of Urology 1991;32(6):941-949
From February 1987 to December 1990, 654 patients with renal stones completed the multiple ESWL monotherapies using the EDAP-LT01 piezoelectric lithotriptor. The location of stones was calyx in 452 patients. pelvis in 1O8. calyx and pelvis in 94 and the stone size ranged from 0.6 to 4.8cm (mean 1.9cm). The number of treatment sessions was 2 to 19 sessions (mean 4.7) with 72.2% of re-treatment rate. In accordance with increment of stone size, number of treatment increased but success rate decreased; 2.8 sessions. 96.2% for 0.6-<1 cm. 4.4, 93.2% for 1-<2 cm, 5.5. 87.7% for 2-<3 cm. 6.3, 65.5% for 3-<4 cm and 6.4, 58.8% for stones larger than 4 cm. Supposing 654 patients had been completed by 5 sessions only. 67.9% of success rate would have been expected. But. 88.4% (578,654) of success rate was obtained by multiple treatment up to 19 sessions, adding 20.5%. Auxiliary ureteral manipulations were required in 88 (13.5%) patients and there were no significant complications. Therefore. multiple ESWL monotherapy is considered to be a efficient. safe procedure as the first applicable method for treatment of larger renal stones and to extend the indications of ESWL for renal stone.
Humans
;
Pelvis
;
Ureter