Abstract
In this study, the influences of fixation of soldering investment and post-heat treatment after welding on the prevention of the welding deformation were investigated by using a 3-unit bridge.
Moreover, the metal die for the welding and fixation bar were made for trial purposes to gain strong fixation, and they were used in the experiment. In addition, the deformations induced bywelding on a super hard stone model, soldering, and one-piece casting were compared with the result of laser welding.
The conclusions were as follows:
In the laser welding of Ag-Pd-Cu-Au alloy, thebest method of obtaining adental prosthesis with good agreement is post-heat treatment after welding, while its castings are fixed stronglytothemetaldiefor welding.
Moreover, the adaptability of the 3-uni tbridge that was welded by this method wasmoreexcellentthan that of the bridge made by soldering or one-piece casting.
As a result, welding on the super hard stone model was undesirable, because large transverse shrinkage was induced and it was not possible to heat-treat it after welding because it was fixed.
