INTRODUCTION: The welding method most commonly used in dentistry can not be applied to pure titanium and its alloys and its alloys due to high reactivity of titanium with the atmospheric elements must not be welded by common process. OBJECTIVE: This study surveyed the characteristics of commercially pure titanium metal intact samples and those laser weld and tungsten inert gas weld. MATERIAL AND METHOD: Fifteen cylindrical rods were developments by using brass rods are patterns. The samples were invested in casings, subjected to thermal cycles, and positioned in a plasma arc-welding machine under argon atmosphere and vacuum, and titanium was injected under vacuum/pressure. Three groups were formed I: laser welding, II, III and TIG welding, without welding. The bodies of the test piece in group I and II were cut in half and welded by TIG and laser, respectively, and group III was maintained intact as control. The metallographic analysis was performed under magnification 50×, 100× and 200× microscope. RESULT: The results obtained in the micrographs, the commercially pure titanium showed an equiaxed grain morphology of α phase, the laser weld bead showed martensitic structure and TIG Widmanstätten microstructure. CONCLUSION: Martensitic microstructure is in agreement with the high cooling rate from the laser welding process. Martensitic and Widmansttäten structures are more refined when compared to the microstructure of the base metal.
Dental soldering; titanium; dental prosthesis; dental implantation