The purpose of this study was to investigate the displacements of cast framework by torch soldering and electric soldering techniques. Specimen had two cylinders and connecting bar that had sectioned with 0.3mm gap at mid point. 10 of total specimens were divided into two groups. In torch soldered group, soldering investment block was made and conventional torch soldering procedure was carried out. In electric soldered group, electric soldering was carried out on the master cast without soldering investment block by using electric soldering machine(Dentapunkt DP 7, Kulzer, Germany). After soldering procedure, three dimensional coordinates of two centroids of each cylinder were measured by three dimensional coordinate measuring machine. The intercentroidal displacement and global displacement were calculated and then, these values were compared and evaluated. The results were obtained as follows: 1. Intercentroidal distances of specimens decreased after both soldering procedures, and the decrease in intercentroidal distance was greater for torch soldered group than for electric soldered group 2. Global displacements of torch soldered group were greater than those of electric soldered group
Investments

PURPOSE: The purpose of this study was to compare the fracture strength of the zirconia monolithic all-ceramic crowns according to the thickness (0.5mm, 0.8mm, 1.1mm) and metal-ceramic crowns (1.0mm, 1.5mm). MATERIAL AND METHOD: Twelve crowns for each of 3 zirconia crown groups were fabricated using CAD/CAM system (Kavo, Germany) and twelve crowns for each of 2 metal-ceramic crown groups were made by the conventional method. All crowns were luted to the metal dies using resin cement. Half of the specimens were exposed to thermocycling (5-55degrees C, 1 Hz) and cyclic loading (300,000 cycles, 50N). Subsequently, all crowns were mounted on the testing jig in a universal testing machine. The load was directed at the center of crown with perpendicular to the long axis of each specimen until catastrophic failure occurred. Analysis of variance and Tukey multiple comparison test (P<.05) were used for statistical analysis of all groups, and paired t-test (P<.05) was followed for statistical comparison between each groups'fracture load before and after cyclic loading. RESULTS: 1. The fracture strength of the zirconia monolithic crowns and the metal-ceramic crown increased as thickness increased (P<.05). 2. The cyclic loading and thermocycling significantly decreased the fracture strength of the zirconia monolithic crowns (P<.05). 3. The standard deviation of fracture strength of the zirconia monolithic crowns was very low. CONCLUSION: The fracture strength of the zirconia monolithic crowns for the posterior area tends to be higher with thickness increased and 0.8mm or over in thickness is recommended to have similar or over the fracture strength of metal-ceramic crowns.
Axis, Cervical Vertebra ; Crowns* ; Resin Cements

No abstract available.
Colorectal Neoplasms* ; Electrophoresis* ; Genes, ras* ; Humans* ; Point Mutation* ; Polymerase Chain Reaction*

No abstract available.
Blood Platelets* ; Humans ; Platelet Aggregation* ; Plateletpheresis* ; Tissue Donors*

BACKGROUND: Inguinal hernia is one of the most common surgical diseases in pediatric patients. We reviewed pediatric inguinal hernia cases retrospectively to analyze the clinical characteristics. METHODS: We reviewed 200 herniorrhaphies in 194 patients who were under the age of 15 and who were operated on at Chungbuk National University Hospital from January 1992 to July 1997. RESULTS: 1) All of the cases were indirect inguinal hernias. Sliding hernias were noticed in 6 cases. High ligations were performed in all cases except 2 cases of Bassini operations. 2) Boys were affected 3.4 times more often than girls. 56.2% of the hernias occurred on the right side, 35.0% on the left side, and 8.8% bilaterally. Bilateral inguinal hernias occurred more often in girls (13.6%) than in boys (7.3%). 3) Hernias were noticed under the age of 1 year (47.9% of the cases). In most of those cases, operations were delayed. Especially, the operations were delayed more than 3 months for 82.1% of patients with hernias and under the age of 6 months. 4) On admission, most patients complained of inguinal or scrotal swelling and inguinal pain or discomfort. 5) Hospitalization occurred in 20.6% of the cases, 3 of which needed emergency operations. Hospitalization occurred in 47.5% of the cases under the age of 1 year; in those cases, hernias were noticed within the first 6 months, and in most of those cases, operations were delayed more than 3 months. 6) Postoperative complications occurred in 9 cases, i.e., 8 cases of scrotal swelling and 1 case of scrotal hematoma. There were no recurrent cases after operation (average follow-up of 33 months). 7) After unilateral inguinal hernia repairs, contralateral hernias developed in 10 patients including 4 patients who had had received their first hernia operations at other hospitals. The sex ratio was 9:1. Laterality of the first hernias were right in 5 cases and left in 5 cases. Contralateral hernias developed within an average of 4.8 months after the first operation; however, 6 cases developed within 6 months after the first operation. CONCLUSIONS: Education for early operation to prevent complications of hernias and careful evaluation of contralateral inguinal hernias in unilateral hernias are needed in the treatment of pediatric inguinal hernias.
Chungcheongbuk-do ; Education ; Emergencies ; Female ; Follow-Up Studies ; Hematoma ; Hernia ; Hernia, Inguinal* ; Herniorrhaphy ; Hospitalization ; Humans ; Ligation ; Postoperative Complications ; Retrospective Studies ; Sex Ratio

STATEMENT OF PROBLEM: Little is known about the effect of a counter-torque device and the internal hexagon of abutment on the tightening torque transmitted to the implant. PURPOSE: The purpose of this study was to examine the effect of a counter-torque device and the internal hexagon of abutment on the tightening torque transmitted to the implant. MATERIAL AND METHODS: In this study, three types of abutment were used; (1) two-piece conical abutment with hexagon, (2) two-piece conical abutment without hexagon, and (3) one-piece conical abutment without hexagon. The experimental groups were divided into five groups according to the type of abutment and the usage of a counter-torque device. Group I : two-piece conical abutment with internal hexagon was tightened without the use of a counter-torque device. Group II : two-piece conical abutment without internal hexagon was tightened without the use of a counter-torque device. Group III : one-piece conical abutment without internal hexagon was tightened without the use of a counter-torque device. Group IV : two-piece conical abutment with internal hexagon was tightened with the use of a counter-torque device. Group V : two-piece conical abutment without internal hexagon was tightened with the use of a counter-torque device. Abutments were tightened 20Ncm torque with the use of manual torque wrench and then torque values were measured by torque-gauge. After the measurement of torque values, all groups were loosened with the use of manual torque wrench and then detorque values were measured by torque-gauge. RESULTS: The results were as follows: 1. There were no differences in torque values among three types of abutment. 2. Regardless of the existence of the internal hexagon of abutment, a counter-torque device decreased the tightening torque transmitted to the implant about 92%. 3. In group III showed the highest detorque value, however there were no differences among group I, II, IV and V. CONCLUSION: Within the limitations of this study, it was concluded that the internal hexagon of abutment has no effect on the tightening torque transmitted to the implant and the detorque value of abutment screw. The use of a counter-torque device is essential to prevent microfracture on the implant-bone interface but has no effect on preload.
Torque*

No abstract available.
Polychondritis, Relapsing*

No abstract available.
Polychondritis, Relapsing*

PURPOSE: To report a case of isolated conjunctival lymphangioma mimicking a recurrent conjunctival cyst. CASE SUMMARY: A 39-year-old male with a conjunctival cyst in the right eye lasted for 1 month visited our hospital. He had previously undergone aspiration of the cyst at another hospital 1 week before visiting our hospital. However, the cyst recurred, and he was referred to our hospital. On slit lamp biomicroscopy, yellow-colored turbid fluid and a hemorrhage were observed in the conjunctival cyst, but no specific finding was found in the fundus photography. The patient was initially treated with topical antibiotics and steroids. Three weeks later, absorption of the hemorrhage was noted, but there was no change in the size of the cyst. Therefore, surgical removal and histological examination of the cyst were performed. The histological examination revealed that the lesion was positive for CD 31 and D2-40, and the cyst was diagnosed as a cystic conjunctival lymphangioma. Thereafter, brain magnetic resonance imaging was performed to screen for orbital lymphangioma and systemic disease that could accompany a conjunctival lymphangioma. However, no specific findings were observed. There was no recurrence of the conjunctival cyst at 1 year and 6 months after surgical removal, and no other ophthalmic or systemic complication was observed. CONCLUSIONS: An isolated conjunctival lymphangioma is a rare lesion. In the diagnosis of lymphangioma, systemic examination is recommended for the identification of comorbid diseases, such as orbital lymphangioma.
Absorption ; Adult ; Anti-Bacterial Agents ; Brain ; Diagnosis ; Hemorrhage ; Humans ; Lymphangioma ; Magnetic Resonance Imaging ; Male ; Orbit ; Photography ; Recurrence ; Slit Lamp ; Steroids