1.Effects of Trypsin, Collagenase and Dimethyl Sulfoxide on Dissociation of Rat Heart Cells.
Chang Woo PARK ; Yung Chang LEE
Yeungnam University Journal of Medicine 1987;4(1):17-23
New born rat heart cells were dissociated using trypsin and/or collagenase to elucidate the dissociation efficiency of these two enzymes. And the effect of dimethyl sulfoxide during and immediately after cell dissociation was also investigated to clarify the so-called protective activity of dimethyl sulfoxide on cell performance. The results can be summarized as follows. 1. Cold trypsin 18 hours pretreatment followed by warm collagenase treatment resulted best cell viability and cell yield. 2. Single warm trypsin treatment gave the poorest result. 3. Dimethyl sulfoxide did not seem to play any protective role during or immediately after rat heart cell dissociation. It had very damaging effect on rat heart cells.
Animals
;
Cell Survival
;
Collagenases*
;
Dimethyl Sulfoxide*
;
Heart*
;
Rats*
;
Trypsin*
2.A Study on The Flexural Bond Strength of The Gold and The Co-Cr Alloy To The Denture Base Resins.
Hyun Joo PARK ; Chang Whe KIM ; Yung Soo KIM
The Journal of Korean Academy of Prosthodontics 2000;38(4):500-509
In general, the three major oral functions of edentulous patients-mastication, phonation, esthetics-can be rehabilitated by the complete dentures, and both the resin based complete denture and the metal based complete denture are commonly used by many clinicians today. For the sake of many advantages such as the excellent thermal conductivity, low volumetric change, high strength, low risk of fracture and the better patient's adaptation, the metal based complete dentures are indicated to the several cases. But, there are common failures of these type of dentures mainly by the fracture or the debonding between the resin structures and the metal frameworks which is caused by the discrepancies by the discrepancies of the flexural strength and the coefficient of thermal expansion. This is aggravated by the water contamination of the interface when exposed to the oral environment and results in the failure of complete denture treatment. So, the purpose of this study is to compare the bond strength and the fracture patterns of the gold alloy based and the Co-Cr alloy based complete dentures using the PMMA resins and the 4-META adhesive resins. The results of this study were as follows. 1. Both to th PMMA resin and the 4-META resin, the flexural bond strength of gold alloy is lower than that of Co-Cr alloy(p<0.05). 2. To the Co-Cr alloy, the bond strength of the 4-META resin is significantly higher tan that of PMMA resin(P<0.05). 3. The flexural strength of the group with the mechanical retention form is significantly higher than that of the group without retention form(P<0.05). 4. Comparing with the other groups, the fracture patterns of the group 3 are quite different from the group 1, 2, 5.
Adhesives
;
Alloys*
;
Denture Bases*
;
Denture, Complete
;
Dentures*
;
Phonation
;
Polymethyl Methacrylate
;
Thermal Conductivity
;
Triacetoneamine-N-Oxyl
3.Clinical study of free vascularized fibular graft.
Yung Khee CHUNG ; Myung Ryool PARK ; Chang Su OH
The Journal of the Korean Orthopaedic Association 1992;27(6):1449-1457
No abstract available.
Transplants*
4.A Case Report of Clear Cell Sarcoma in Thigh
Yung Khee CHUNG ; Won Chang PARK ; Ik Yull CHANG ; Chang Rock OH
The Journal of the Korean Orthopaedic Association 1982;17(1):158-160
Malignant tumors arising from tendon and aponeurosis are very rare. Among those reported most have been interpreted as synovial sarcoma or fibrosarcoma until Enzinger in 1965 described a new type which he called “Clear Cell Sarcoma of Tendon and Aponeurosis”. The tumor has a uniform and distinctive clinical and morphological pattern which distinguishes it from other groups of tenosynovial tumors. The problem of its histogenesis remains, especially its relation to synovial sarcoma. In this paper, we reported one case which is believed to be “Clear Sarcoma in the thigh”.
Clothing
;
Fibrosarcoma
;
Sarcoma
;
Sarcoma, Clear Cell
;
Sarcoma, Synovial
;
Tendons
;
Thigh
5.A Clinical Study of the Fractures of the Femoral Neck in Children
Yung Khee CHUNG ; Jung Soo PARK ; Won Chang PARK ; Ik Yull CHANG ; In Ho HWANG
The Journal of the Korean Orthopaedic Association 1984;19(5):925-933
Fractures of the femoral neck in children are rare and usually occur as a result of severe trauma. They are one of the most challenging injuries to treat. Their complication rate is high and their anatomic and physiologic characteristics make treatment difficult. The commonly encountered complications are avascular necrosis, nonunion, coxa vara and premature fusion of epiphyseal plate. Treatment of these fractures remains an unsolved problem but accurate reduction held with adequate internal fixation would appear to offer the best chance for succesful results. We report our observations in the treatment of eighteen cases of fracture of the femoral neck in children. Included is a review of references. The results obtained are as follows: 1. Among 18 patients, 11 were boys and 7 were girls. the highest incidence was between the ages of 5 and 7 years. 2. The main causes of fractures were traffic accidents in 10 cases (55.5%), falling from a height, and slipping down. 3. The commonest type of fracture was the cervicotrochanteric type (47.4%). Twelve cases were displaced fractures (66.7 %). 4. The range of Pauwels angle varied from 20° to 70°. 5. The commonly associated injuries were pelvic bone fractures, extremity fractures, skull fractures and soft tissue injuries. 6. Nine cases were treated by skin traction and plaster cast. Five cases ere treated by closed reduction and internal fixation with K-wires or knowles pins. 7. In 13 of the 18 cases, follow-up studies were done for an average period of 18 months. 8. The results were analyzed according to the Ratliffs assessment. Among the 13 cases, 10 cases showed good results, two fair and one poor. 9. All cases treated by closed reduction and internal fixation showed good results without complications. 10. Complications developed in five cases (38.5%), three cases of avascular necrosis and two cases of coxa vara. Among these five cases, one case of avascular necrosis developed as a result of neglect of the fracture and the others as a result of too conservative a treatment. 11. Secondary treatment of trochanteric arthroplasty was required in only one neglected case. This was further by avascular necrosis and the results were poor. 12. As a result, we recommond closed reduction and internal fixation as the most favorable method of treatment for the fracture of the femoral neck in children.
Accidental Falls
;
Accidents, Traffic
;
Arthroplasty
;
Casts, Surgical
;
Child
;
Clinical Study
;
Coxa Vara
;
Extremities
;
Female
;
Femur
;
Femur Neck
;
Follow-Up Studies
;
Growth Plate
;
Humans
;
Incidence
;
Methods
;
Necrosis
;
Pelvic Bones
;
Skin
;
Skull Fractures
;
Soft Tissue Injuries
;
Traction
6.Spinal Stenosis: Review of 40 Cases
Yung Khee CHUNG ; Won Chang PARK ; Ik Yull CHANG ; Sung Wan KIM
The Journal of the Korean Orthopaedic Association 1982;17(5):808-814
Spinal stenosis is defined as any type of narrowing of the main spinal canal, nerve canal or foramina caused by bony or sourrounding soft tissues. Its pressure symptoms are characterized by ill localized back pain, and usually bilateral chronic sciatica. During the past 80 years, the knowledge subjected to the spinal stenosis has been inproved but still many problems are remaining to be solved. Recently, the diagnosis and treatment of spinal stenosis have been facilitated due to introduction of computerized tomographic scanning apparatus. During the period of 3 years, from May 1979 to March 1982, we experienced 40 cases of spinal stenosis at Han Gang Sacred Heart Hospital and Gang Nam Sacred Heart Hospital. In study of this 40 cases clinical and radiological evaluation were made and obtained following result (25 cases of which were operated on). 1. The most common type was degenerative one (50%) 2. There were 16 males and 24 females (4:5) 3. The age distribution showed a peak incidence is the third decade (25%) 4. The most common chief complaint on admission was ill localized chronic sciatica (50%) 5. Decompressive surgery was carried on 25 cases such as; Laminectomy only (8%), Posterolateral fusion (20%), Both Laniinectomy and posterolateral fusion (72%) 6. The longest follow-up was 3 years and the shortest one was 4 months and the average was one year and four months. The outcome of follow-up were; excellent (52%), good (40%), fair (8%), poor (0%).
Age Distribution
;
Back Pain
;
Diagnosis
;
Female
;
Follow-Up Studies
;
Heart
;
Humans
;
Incidence
;
Laminectomy
;
Male
;
Sciatica
;
Spinal Canal
;
Spinal Stenosis
7.Surgical Management of Bone Infection (14 Cases Treated by papineau's Method)
Ik Yull CHANG ; Yung Khee CHUNG ; Won Chang PARK ; Jung Han YOO
The Journal of the Korean Orthopaedic Association 1983;18(2):286-296
Papineau's technique represents an excellent method of dealing with serious bone infections with significant bone and soft tissue loss. The procedure is carried out in three stages: the 1st stage is the excision of infected bone and soft tissue, stabilization of the fracture site, the 2nd stage is the cancellous bone grafting, and the 3rd stage is the skin coverage. During the period from June 1980 to September 1982, our limited experience with 14 cases has been extremely satisfactory; 1. This method is applicable to traumatic osteomyelitis and some cases in which the infection has been blood borne. 2. Successful bone grafting in the presence of infection depends upon; a. complete sequestrectomy and removal of all infected tissue b. an adequate vascular bed for the graft c. no dead space d. sufficient immobilization.
Bone Transplantation
;
Immobilization
;
Methods
;
Osteomyelitis
;
Skin
;
Transplants
8.Multiple Fractures of Forearm & Humerus by Belt Injuries
Ik Dong KIM ; Soo Young LEE ; Poong Taek KIM ; Byung Chul PARK ; Chang Yung PARK
The Journal of the Korean Orthopaedic Association 1986;21(1):137-142
In the workshops where the rorating belts are used belt, injuries frequently occur for lack of a safety device. Those injuries have several characteristics compared with other long bone fractures. Those are mostly multiple open fractures with considerable soft tissue damages, forearm both bones and humerus fractures by bending force and rotational distraction as mechanism of the injury, and sometimes particularly segmental fracture of the radius. From Aug. 1972 to Jan. 1985, we have traced 47patients of multiple fractures of forearm and humerus by belt injuries except 17 patients of solitary fractures of forearm and humerus. 1. This injury is more prevalent in males(M:F=4:1) with the peak incidence between the third and fourth deades(59%). 2. Multiple fractures of forearm and humerus by belt injuries were classified by fracture numbers and mechanism of injury as follows: Type I Fractures of Forearm Both Bones(53.2%). Type II Fractures of Forearm Both Bones and Humerus(27.7%). Type IU Segmental Fracture of Radius and Ulna(10.6%). Type IV Segmental Fracture of Radius, Ulna and Humerus(8.5%). 3. Most were open fractures with soft tissue damages(74%). 4. Nerve paralysis was the most frequent associated injury(27%). 5. All but 7 cases were treated by open reduction. Implants used for internal fixation were compression plates in 20 cases as elective surgery and Rush pins in 15 cases of forearm open fractures as emergency surgery. 6. By Anderson's critcria, satisfactory result(excellent or good) was obtained in 55% of cases.
Education
;
Emergencies
;
Forearm
;
Fractures, Bone
;
Fractures, Multiple
;
Fractures, Open
;
Humans
;
Humerus
;
Incidence
;
Paralysis
;
Protective Devices
;
Radius
;
Ulna
9.Effects of Dimethyl Sulfoxide on the Differentiation of Myocardial and Endothelial Cells.
Dong Hyup LEE ; Yee Tae PARK ; Sung Sae HAN ; Yung Chang LEE
Yeungnam University Journal of Medicine 1988;5(2):111-119
To elucidate the effects of dimethyl sulfoxide on of myocardial and endothelial cells in culture, the cells were exposed to 10% dimethyl sulfoxide in culture medium for 1 hour at 48 hours after cell isolation. The general morphology and the cytochemical reaction of marker enzymes for mitochondria and Golgi complexes were investigated. The results were summarized as follows 1. DMSO induced elongation and narrowing of the cells and increase of mitochondrial reaction in myocardial cells. 2. DMSO induced destruction and disruption of myofibrils in myocardial cells resulting in increase of contractile activities. 3. In the endothelial cells, DMSO suppressed proliferative activities but thiamine pyrophosphatase reactions were enhanced indicating increase of Golgi complex activity. 4. DMSO seemed to hamper with the adhesiveness and motility of the endothelial cells causing the decrease of the number of cells in vitro.
Adhesiveness
;
Cell Separation
;
Dimethyl Sulfoxide*
;
Endothelial Cells*
;
Golgi Apparatus
;
In Vitro Techniques
;
Mitochondria
;
Myofibrils
;
Thiamine Pyrophosphatase
10.A study on the adhesion of a soft liner containing 4-META to the base metal alloy and its viscoelastic property.
Hyun Joo PARK ; Chang Whe KIM ; Yung Soo KIM
The Journal of Korean Academy of Prosthodontics 2003;41(6):732-746
STATEMENT OF PROBLEM: Soft lining materials, also referred to as tissue conditioning materials, tissue treating materials, relining materials, soft liners or tissue conditioners, were first introduced to dentistry by a plastic manufacturer in 1959. Since the introduction of the materials to the dental field, their material properties have been continually improved through the effort of many researchers. Soft lining materials have become widely accepted, particularly by prosthodontists, because of their numerous clinical advantages and ease of manipulation. Unfortunately, few reports have been issued upon the topic of increasing the bond strength between the base metal alloy used in cast denture bases and PMMA soft liner modified with 4-META, nor upon the pattern of debonding and material change in wet environment like a intra oral situation. PURPOSE: The purposes of this study were comparing the bond strength between base metal alloy used for the cast denture bases and PMMA soft liner modified with 4-META, and describing the pattern of debonding and material property change in wet environment like the intraoral situation. MATERIAL AND METHODS: This study consisted of four experiments: 1. The in vitro measurement of shear bond strength of the adhesive soft liner. 2. The in vitro measurement of shear bond strength of the adhesive soft liner after 2 weeks of aging. 3. A comparison of debonding patterns. 4. An evaluation the gelation time of modified soft liner. The soft liner used in this study was commercially available as Coe-soft (GC America.IL., USA), which is provided in forms of powder and liquid. This is a PMMA soft liner commonly used in dental clinics. The metal primer used in this study was 4-META containing primer packed in Meta fast denture base resin (Sun Medical Co., Osaka, Japan). The specimens were formed in a single lap joint design, which is useful for evaluating the apparent shear bond strength of adhesively bonded metal plate by tensile loading. Using the 20x20mm transparent grid, percent area of adhesive soft liner remaining on the shear area was calculated to classify the debonding patterns. To evaluate the change of the initial flow of the modified adhesive soft liner, the gelation time was measured with an oscillating rheometer (Haake RS150W/TC50, Haake Co., Germany). It was a stress control and parallel plate type with the diameter of 35mm. CONCLUSION. Within the conditions and limitations of this study, the following conclusions were drawn as follows. 1. There was significant increase of bond strength in the 5% 4-META, 10% 4-META containing groups and in the primer coated groups versus the control group(P<0.05). 2. After 2 weeks of aging, no significant increase in bond strength was found except for the group containing 10% 4-META (P<0.05). 3. The gelation times of the modified soft liner were 9.3 minutes for the 5% 4-META containing liner and 11.5 minutes for the 10% 4-META liner. 4. The debonding patterns of the 4-META containing group after 2 weeks of aging were similar to those of immediaely after preparation, but the debonding pattern of the primer group showed more adhesive failure after 2 weeks of aging.
Adhesives
;
Aging
;
Alloys*
;
Dental Clinics
;
Dentistry
;
Denture Bases
;
Joints
;
Plastics
;
Polymethyl Methacrylate