I had gastric bypass 43 days ago. All of a sudden there was a dark line across my three top front teeth. I swear it appeared in like a day. I was not taking calcium pills because I was not told to do so. I did put my self on them about 4 days ago when I seen the darkness in my smile. Its terrible that's the one thing people always said about me was how nice my smile was. Now its gone. ok pity party over I really just want to know if anybody has had this problem. Thank you in advance.