[Displacement and distortion of non-precious ceramometal fixed bridges during the laboratory procedure. Non-precious metal].
The purpose of this study is to measure the three-dimentional displacement and distortion in the Non-precious (Ni-Cr) ceramometal bridges during laboratory procedure. At the time of pre-soldering stage, the author examined the phosphatic investment (low and high thermal expantion: ph, ps) to addition of gypsum investment which was usually to used to fix the position for soldering. The following results were obtained. 1. The displacement of the framework at the pre-soldering stage, in case of using phosphatic investment mixed by water (ph), it was small on the horizontal and vertical plane. And in the other case of mixing by 100% colloidal silica (ps), a kind of displacement was seen where the curve of the bridge opened as result of the position of two soldering bodies getting out of order from each other. So that phosphatic bonded investment, it can be used to because thermal expantion can be controlled, the soldering block. 2. Throughout the surface grinding of framework to grazing, displacement was minimal, at the time of opaque porcerain firing, the curve of the bridge closed but it had no effect on clinical adaptation. 3. In the case of assembling multi-unit non-precious ceramometal bridge mainly the displacement caused at pre-soldering stage, so it is important to check the adaptation after soldering.
Hagiwara
Y
Y
D002858:Chromium Alloys; D003734:Dental Casting Investment; D003776:Dental Porcelain; D012994:Dental Soldering; D003799:Dental Stress Analysis; D003779:Denture Design; D003830:Denture, Partial, Fixed; D006801:Humans
D002858:Chromium Alloys; D003734:Dental Casting Investment; D003776:Dental Porcelain