Abstract:

BACKGROUND: NEO cobalt chromium ceramic alloy does not contain harmful substance, but whether it can be reused is still unclear. There are few reports about the effects of recasting on properties of NEO ceramic alloy.
OBJECTIVE: To investigate the effects of recasting on bonding properties, metallurgical structure and morphology of metal-ceramic interface of NEO cobalt chromium ceramic alloy.
METHODS: The NEO cobalt chromium ceramic alloys were casted by argon pressure casting in vacuum condition according to ISO9693. The bonding properties of NEO cobalt chromium ceramic alloys after recasting for 1-5 times were tested by three-point bending test. Metalloscope was used to observe the metallurgical structures of each generation of casting, and their morphologies of metal-ceramic interface were observed by scanning electron microscope.
RESULTS AND CONCLUSION: There were differences in bonding properties of NEO cobalt chromium ceramic alloys after recasting for 1-5 times (P < 0.05). With the increase in recasting time, the dendritic structures and grain structures of castings were gradually blurred and disappeared, the combination of metal-ceramic interface was gradually loosening and the thickness of transition layer was increased. It is indicated that recasting can significantly affect the bonding properties of NEO cobalt chromium ceramic alloy.