Thanks for all the responses so far, eat comments by all, and great work martintay; thanks for sharing. So, galvanic reaction aside...well not so quick. What are the effects of galvanic reaction to fixture and tissue (hard and soft)?
Now galvanic action aside how do you guys address the oxide build up after pocrelain firing. Do you glass bead or chemically treat to remove oxide? My indoctrination back in the day was that you leave the mating surface to the platform pristine, virgin. But that was using N & HN alloys and manufactured abutments which did not oxidize during porcelain cycles. Now with NP (CrCo) I experienced oxidation, much different to what John stated. If left untreated this may lead to tatooing the tissue around the margins over time. Even the screw access became tighter after firing due to oxidation growth, I know this can be addressed with a reamer. But this is happening to the exposed metal during firing and that means the mating surfaces are being altered by the oxide buildup. If glass beaded, then the mating surface is altered. Aside from using N & HN alloys how do you guys avoid this. Why would anyone use an alloy thats not only challenging in the laboratory but will cause clinical problems later down the road?