The influence of the die hardener on gypsum die / 대한치과보철학회지

STATEMENT OF PROBLEM: Die materials require abrasion resistance, dimensional stability with time, and high surface wettability for adequate material properties. Wear of gypsum materials is a significant problem in the fabrication of accurately fitting cast prosthetic devices. So It has been recommended that the use of die hardener before carving or burnishing ofthe wax pattern. PURPOSE: The purpose of this study was to compare the abrasion resistance and surface microhardness(Knoop) with 3 commonly used gypsum die materials(MG Crystal Rock, Super plumstone, GC FUJIROCK(R) EP) with and without the application of 2 die hardeners. MATERIAL AND METHODS: Three die materials were evaluated for abrasion resistance and surface microhardness after application of 2 die hardeners(Die hardener and Stone die & plaster hardener). Thirty specimens of each gypsum material were fabricated using an impression of resin die(Pattern resin; GC Corporation, Japan) with 1-mm high ridges, sloped 90 degrees. Gypsum materials were mixed according to manufacturer's recommendations and allowed to set 24 hours before coating. Specimens were arbitrary assigned to 1 of 3 treatment subgroups (n=10/subgroup): no treatment(control), coated with Die hardener, and coated with Stone die & plaster hardener. Abrasion resistance(measured by weight loss) was evaluated using device in 50g mass perpendicular to the ridges. Knoop hardness was determined by loading each specimen face 5 times for 15 seconds with a force of 50g. A scanning electron microscope was used to evaluate the surface of specimens in each treatment subgroup. Conclusions: The obtained results were as follows: 1. 3 types of die stone evaluated in this study did not show significant differences in surface hardness and abrasive resistance(P<.05). 2. In the abrasive resistance test, there were no significant differences between GC FUJIROCK(R) EP and MG Crystal Rock with or without 2 die hardener(P<.05). 3. Super plumstone treated with Stone die & plaster hardener showed increased wear loss(P<.05). 4. Die hardener coatings used in this study decreased the surface hardness of the gypsum material(P<.05).

Treatment of Hepatic Cavernous Hemangioma:A Report of 47 Cases / 中国医师杂志

Objective To summrize the effects of various treatment methods,including operation,transcatheter arterial embolization(TAE),and percutaneous ethanol injection(PEI) on hepatic cavernous hemangioma(HCH),in order to select an optimal therapy strategy for HCH.MethodsClinic data of 47 patients with 58 hepatic hemangiomas treated in our hospital in recent 10 years were analyzed retrospectively.Results There were 26 males and 21 females with mean age 42?2 5 years(10～72 years old)in this series.The diameters of these lesions were 3～21 5cm(mean diameter 8 5?1 8cm).Of them,obvious symptoms appeared in 39 patients,malignancy could not excluded in 6,and the size of HCH increased rapidly in 2.Operations were performed in 40 patients,including 2 patients failed to PEI;TAE was conducted in 7cases.There was no mortality or major morbidity occurred in the operative patients,except right pleual effusion in one case and subdiaphragmatic fluid collections in another case(2/40).Neither is mortality nor morbidity seen in the TAE treated case.Conclusions Operation is an effective procedure for HCH.But for more diffuse lesions or lesions located in special region,TAE is a more favorable alterative selection.Because PEI has risk of hemorrhage and hardener injection under ultrasonography guide has uncertain outcome,so it should be chosen cautiously.