The purpose of this study was to investigate the stress distribution of the abutment and supporting tissues according tot he slopes and types of the guiding plane of distal extension removable partial dentures. The 3-dimensional finite element method was used and the finite element models were prepared as follows. Model I : Kratochvil type guiding plane with 90degree to residual ridge Model II : Kratochvil type guiding plane with 95degree to residual ridge Model III : Kratochvil type guiding plane with 100degree to residual ridge Model IV : Krol type guiding plane with 90degree to residual ridge Distal extension partial denture which right mandibular first and second molar were lost was used and the second premolar was prepared as primary abutment with RPI type retainer. Then 150N of compressive force was applied to central fossae of the first and second molars and von Mises stress and displacement were measured. The results were as follows : 1. Model I and Model IV showed a similar stress distribution pattern and the stress was concentrated on the apex of the root of the abutment. 2. The stress was increased and concentrated on mesial side of the root of the abutment in Model II. The stress was concentrated on buccal and mesiobuccal side of the root of the abutment in Model III. 3. In Model I, the root of the abutment displaced and twisted a little in clockwise. In Model IV, the root of the abutment displaced to distolingually at apical region of the root and mesiobucally at cervical region of the root. 4. In Model II, the root of the abutment displaced to mesiolingually at apical region of the root and more displaced and twisted in counterclockwise at cervical region of the root. In Model III, the root of the abutment displaced to mesiobucally at apical region of the root and more displaced and twisted in clockwise at cervical region of the root.
Bicuspid ; Denture, Partial ; Denture, Partial, Removable* ; Molar

The effects of pretreatment of Co-Cr alloy, including two adhesive primers that contain either MDP or MAC-10, and silicoating on the bond. The results obtained as follows : Strength of 4-META/MMA-TBB resin were investigated using FT-IR SEM, and EDAX. in the SEM observation of surface morphologies, the sandblasted specimen exibited a very rough surface, whereas the surfaces of the two groups primed with either MDR or MAC-10 were covered with a layer of primer, and the surface morphology of the silicoated specimen remained almost the same after sandblasting. Before the thermocycling tests, the group treated with MDP demonstrated the highest mean tensile bond strength and the sandblasted group showed the lowest bond strength. After 20,000 themocyling, the mean tensile bond strength of the sandblasted group exhibited a 50% reduction in bond strength, while the other showed a 20~30% reduction. Observation of the metal-resin interface revealed that in all groups the resin permeated the rough surface formed by sandblasting thereby producing a mechnical bond between the metal and the resin, It was also found that thermocycling resulted in a gap formation at the metal-resin interface of the specimens, and the sandblasted group exhibited a larger gap width than the other groups. in fracture mode, all specimens indicated a cohesive fracture within the resin before thermocycling. However, thermocyling produced adhesive failure at the edge of the resin-metal interface in most specimens, The sandblasted group, which exhibited the lowest bond strength after thermocycling, also demonstrated the largest area of adhexive failure.
Adhesives ; Alloys*

The light therapy has been known to be effective to non-seasonal affective disorder as well as seasonal affective disorder. Although the mechanism of action of light therapy for depressive disorder has not been verified yet, its clinical application revealed similar effects like antidepressants and relatively smaller side effects. However, it is not common to apply the light therapy for treatment resistant depressive disorder. This case report indicates a robust efficacy of light therapy and its clinical usefulness, illustrating the complete remission in a treatment resistant patient with major depressive disorder after bright light therapy.
Antidepressive Agents ; Depressive Disorder ; Depressive Disorder, Major* ; Humans ; Mood Disorders ; Phototherapy* ; Seasonal Affective Disorder

Biliary atresia is a surgical disease of infancy with a very poor prognosis usually attributed to the rarity of surgically correctable case. This paper presents a case of incorrectable type of biliary atresia 50 days old Direan female infant who were subjected to the Modified Kasai Operation She had shown good bile excretion after surgery but developed recurrent fever, severe hypocalcemia and roentgenographically prover rickets during the follow up periods. She died 7 months after the operation.
Bile ; Biliary Atresia* ; Female ; Fever ; Follow-Up Studies ; Humans ; Hypocalcemia ; Infant ; Prognosis ; Rickets

Telomerase activity has been detected in many human immortal cell lines and tumor tissues. We studied telomerase activity in a series of human musculoskeletal tumors. Twenty-eleven tumors from 27 patients were studied using a sensitive PCR (polymerase chain reaction)-based technique, the TRAP(telomeric repeat amplication protocol) assay. Telomerase activity was present in seven tumors(25.9%). Telomerase activity was present in six of 18 malignant tumors(33.3%), while telomerase was active in one of 9 benign tumors(11.1%). Telomerase was active in 40% for osteosarcomas, 25% for soft tissue sarcomas, 16.7% for giant cell tumors of bone, and none for benign tumors. These results are a remarkablely low positive rate of telomerase activity in comparing with other types of carcinoma. In conclusion, it suggests that the musculoskeletal tumors, arisen from mesenchymal cells, follow different pathways of neoplastic progression or it is due to tile specific characteristics stick of sarcomas-abundant extracellular matrix and lack of tumor cells-differed tumor those of carcinomas.
Cell Line ; Extracellular Matrix ; Giant Cell Tumors ; Humans ; Osteosarcoma ; Polymerase Chain Reaction ; Sarcoma ; Telomerase*

BACKGROUND: We studied the hemodynamic changes induced by pneumoperitoneum and a reversed Trendelenburg in elderly patients with increased cardiac risk (ASA class III; n = 30; age 70.8 +/- 4.9 years, mean +/- SD) and compared the results with elderly patients at normal risk (ASA class II; n = 30; age 69.2 +/- 4.1 years) during laparoscopic cholecystectomy. METHODS: The transesophageal Doppler monitor was performed after induction of general anesthesia (pre-incision), after onset of pneumoperitoneum (insufflation), after head-up (20degrees) and a left lateral tilt (15degrees) (reversed Trendelenburg) and after deflation and horizontal position (desufflation). Mean arterial pressure (MAP), heart rate, cardiac index (CI) and systemic vascular resistance (SVR) were measured, respectively. RESULTS: Induction of pneumoperitoneum and head-up tilt in patients with cardiac risk resulted significantly in a decrease in CI and an increase in SVR compared with patients with normal risk (P < 0.05), and that remained until deflation, but no interval changes in MAP and heart rate. The CI, MAP and heart rate decreased and SVR increased significantly in patients with cardiac risk compared with patients with normal risk before incision (P < 0.05). No complications occurred. The results indicate that pneumoperitoneum and a reversed Trendelenburg are associated with significant but relatively benign hemodynamic changes. CONCLUSIONS: Anesthesia for laparoscopic cholecystectomy in elderly patients with increased cardiac risk should be performed with an adequate hemodynamic monitoring.
Aged ; Anesthesia ; Anesthesia, General ; Arterial Pressure ; Cholecystectomy, Laparoscopic ; Heart Diseases ; Heart Rate ; Hemodynamics ; Humans ; Organothiophosphorus Compounds ; Pneumoperitoneum ; Vascular Resistance

BACKGROUND: The hemodynamic and metabolic effects of tourniquet application undergoing knee surgery with general anesthesia in elderly patients with hypertension have been rarely reported. We evaluated the hemodynamic and metabolic effects in elderly patients compared with young adults. METHODS: Thirty elderly patients (elderly hypertension group, 71.8 +/- 3.9 years) with chronic hypertension undergoing total knee replacement and 30 young adults (normal group, 33.1 +/- 5.1 years) undergoing knee surgery were studied. Mean arterial pressure (MAP), heart rate, cardiac index (CI) by esophageal doppler method, and systemic vascular resistance index (SVRI) were measured before, during, and after tourniquet application. pH, PaO2, PaCO2, Hb and lactate blood concentrations were also measured. RESULTS: MAP increased 25% and 16% in elderly hypertension and normal groups during inflation, respectively (P < 0.05) and returned to basal values after deflation. CI increased to 30% higher than basal values in both groups after deflation (P < 0.05). SVRI decreased 31% and 19% in elderly hypertension and normal groups after deflation, respectively (P < 0.05). After deflation, PaCO2 and lactate increased (P < 0.05). CONCLUSIONS: Elderly patients with hypertension have the significant hemodynamic changes during and after tourniquet application than before, however, there are no differences compared to normal group. These elderly patients should be needed the active hemodynamic monitoring due to the lower compensatory ability.
Aged* ; Anesthesia, General ; Arterial Pressure ; Arthroplasty, Replacement, Knee ; Heart Rate ; Hemodynamics* ; Humans ; Hydrogen-Ion Concentration ; Hypertension* ; Inflation, Economic ; Knee* ; Lactic Acid ; Tourniquets* ; Vascular Resistance ; Young Adult

BACKGROUND: Atracurium appears to be a neuromuscular blocking agent best suited for use in patients with renal failure. The influence on the neuromuscular effect of atracurium has been studied in rabbits with experimental liver cirrhosis induced by subcutaneous injection of carbon tetrachloride (CCl4). METHODS: Cirrhosis was induced in rabbits by CCl4 treatment for 11 weeks. Rabbits were randomly assigned to two groups; control group: corn oil 0.5 ml/kg/2 days sq for 11 weeks; study group: CCl4 0.5 ml/kg/2 days mixed 1 : 1 with corn oil sq for 11 weeks. The dose-response relations of atracurium were studied in sixteen rabbits during thiopental anesthesia. They received atracurium 60, 80 and 100microgram/kg in control group, and 80, 100 and 120microgram/kg in study group, respectively. The time course of atracurium 0.2 mg/kg in sixteen rabbits was evaluated in each groups. Three fragments of each liver lobe at the end of the experimental period were collected and processed for light microscopy, and performed the histological examination. RESULTS: After eleven-week CCl4 treatment, liver histology demonstrated well-defined liver cirrhosis, and increased AST and ALT compared with controls. The calculated ED50 for atracurium were 81.9+/-6.8microgram/kg and 101.1+/-9.4microgram/kg, respectively, in control and study group, and corresponding ED95 was 124.8+/-9.7microgram/kg and 156.1+/-12.1microgram/kg, respectively. There were significant difference between two groups (P < 0.001). The times after atracurium until 95% twitch recovery in control and study group were 31.7+/-6.7 min and 32.8+/-7.4 min, respectively. There were no difference between two groups. CONCLUSIONS: Atracurium in the experimental liver cirrhosis model induced by CCl4 has a decreased potency, but a similar duration of action compared with control. It is suggested that atracurium was also used with monitoring of neuromuscular function in patients with hepatic dysfunction.
Anesthesia ; Atracurium* ; Carbon Tetrachloride* ; Carbon* ; Corn Oil ; Fibrosis ; Humans ; Injections, Subcutaneous ; Liver Cirrhosis* ; Liver Cirrhosis, Experimental ; Liver* ; Microscopy ; Neuromuscular Agents ; Neuromuscular Blockade ; Rabbits* ; Renal Insufficiency ; Thiopental

BACKGROUND: Invasive central venous catheterization is necessary in critically ill patients for hemodynamic monitoring and for administration of hypertonic fluids, drugs, and parenteral nutrition. Common access sites are the internal jugular veins, subclavian veins, and femoral veins. Yoffa's percutaneous supraclavicular subclavian vein catheterization technique has some disadvantages and difficulties which include dislodgement of the puncture needle and difficult enhancement of the guide wire. To overcome these problems, we modified Yoffa's technique as a symmetrical puncture against the clavicle. METHODS: A patient was placed supine with his/her head turned to the opposite side with the arm at the side. The needle was inserted through the skin at a point around 1 cm below the clavicle, toward the imaginary midline of the clavicular head of the sternocleidomastoid muscle (SCM). The guide wire was inserted with a J-wire. Measurements were made to determine the length from the puncture site to the lower border of the clavicle, the depth and angles from the needle to mid sagittal line, the coronary line and skin (Fig. 2). We also evaluated the No. of punctures, wire insertions, and complications. RESULTS: Our success rate was 95.1% and 6 cases with complications (5.9%) occurred in 102 attempts. The most serious complication was a delayed tension pneumothorax 6 h postoperatively. CONCLUSIONS: These results suggest that the new landmark for infraclavicular subclavian vein catheterization is an easy and safe procedure for an experienced physician. We also recommend close observation postoperatively for at least 24 h for complications.
Arm ; Catheterization* ; Catheterization, Central Venous ; Catheters* ; Central Venous Catheters ; Clavicle ; Critical Illness ; Femoral Vein ; Head* ; Hemodynamics ; Humans ; Jugular Veins ; Needles ; Parenteral Nutrition ; Pneumothorax ; Punctures ; Skin ; Subclavian Vein*

BACKGROUND: Patients with obstructive sleep apnea syndrome (OSAS) exhibits repititive, prolonged episode of apnea during sleep with serious nocturnal and diurnal physiologic derangements. With their physiologic derangements, they are often obese, very sensitive to central depressant drugs and difficult to intubate. The purpose of this paper is to evaluate the potential problems encountered in anesthetic management of adult OSAS. METHODS: Anesthetic records of 28 patients with OSAS who had undergone the uvulopalatopharyngoplasty (UPPP) under the general anesthesia during the period of 1981 and 1996 years were analysed retrospectively. RESULTS: Although past anesthetic records were not recorded completely, we discovered that the policy in selection of drugs with shorter duration of action time and not using central depressant drugs during the induction of anesthesia of adult OSAS patients were not kept. CONCLUSIONS: Sleep apnea syndrome presents the anesthetists with many implications. In addition to difficulties of tracheal intubation imposed by anatomical features, these patients are sensitive to central depressant drugs particularly opioids. Anesthetic care, postoperative analgesia, cardiorespiratory management need to be handled with care.
Adult ; Analgesia ; Analgesics, Opioid ; Anesthesia ; Anesthesia, General* ; Apnea ; Humans ; Intubation ; Postoperative Care ; Retrospective Studies ; Sleep Apnea Syndromes ; Sleep Apnea, Obstructive*