If the white spot is located on the biting surface it might be the opaque material the lab places to block out the darkness of the metal underneath the porcelain. If that is the case then it is possible that the porcelain is too thin in that area. More than likely nothing will happen.I am not sure what you mean by not snug by your gum. As long as the crowns fit the margins of the prepared teeth and there is no cosmetic concerns then the bridge should do well.
Thank you, the white spot is on the front of the bridge.
What I mean by the crown not being snug to the gumline is that if I floss, I can feel and see the ridge were the tooths root surface meet the bottom of crown. On my PROCERA, I do not have this problem. Normal?
seeing the ridge is ok, as long as there is not a cosmetic concern. as long as the margins are closed (well adapted to the prepared tooth structure) this is ok, and actually prefeerable becasue the tissue is less likely to get irritated. procera has no metal so the margins are less visible. the white spt indeed is porbably opaquer-- it means the porcelain is thin. if the cosmetics of this bother yoiu enough you should speak to the dentist about it, or get a 2nd opinion.