title: Effects of four mixing methods on setting expansion and compressive strength of six commercial phosphate-bonded silica investments.
abstract: Six commercial phosphate-bonded silica investments were mixed with four different mixing methods such as hand, two conventional blade-driven vacuum mixers and a new planetary mixing device, and examined for their setting expansion and compressive strength. The two properties often altered, depending upon the mixing method and the investment. The setting expansion of three investments were significantly affected by the mixing method while those of the other three were not. Compressive strength of all six investments varied by changing the mixing method. It is emphasized here that a mixing method and mixing condition must be properly set for each investment to improve the fit of the final metallic castings. This study also suggests that the planetary mixing device is a useful substitute for conventional blade-driven vacuum mixers.
authors.affiliation: Department of Dental Materials Science and Technology, Osaka University Faculty of Dentistry, and Taisei Dental Manufacturing Corporation Limited, Osaka, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Taira
authors.forename: M
authors.initials: M
authors.lastname: Okazaki
authors.forename: J
authors.initials: J
authors.lastname: Takahashi
authors.forename: F
authors.initials: F
authors.lastname: Kubo
mesh_terms: D019245:Compressive Strength; D003734:Dental Casting Investment / Q000737:chemistry*; D003735:Dental Casting Technique / Q000295:instrumentation; D008422:Materials Testing / Q000379:methods / Q000706:statistics & numerical data; D010710:Phosphates / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D003734:Dental Casting Investment; D010710:Phosphates; D012822:Silicon Dioxide