Effect of venting on cast gold full crowns

摘要: I t would be highly desirable if the marginal opening of a crown could reduced significantly by venting before cementation without making any other alteration casting. Both electrochemical milling and etching require long time. Also, equipment that is necessary to do not generally available practitioner. Although stripping can done with aqua regia, amount gold removed process at best an estimate time-consuming. Therefore, procedure accomplished chair, minimum time equipment, help dentists improve adaptation full-crown castings. In 1966, study’ was made determine type margin cast restoration acceptable experienced dentists. The results showed interproximal margins from 34 microns up 119 were acceptable. This study underlines difficulties involved in using explorer radiographs evaluate subgingival after restoration. One most common causes failure solubility luting agent used cement restoration.’ Because rate washout related exposed margin, anything reduce will increase restoration’s chance for success. Several factors influence cementation. Of these factors, consistency mixed contour preparation are important considerations, but cemented go completely place on prepared tooth also source error. result incomplete seating increased margins.