Hello all. I really hope somebody can enlighten me here.
I have a question regarding a dentist who wants to do either an implant, bottom left, 5th from back, or a bridge. the tooth is broken vertically and a disaster. Anyway, here is my question. He says he would like to do a bridge, and while surveying my teeth, he was looking at the tooth above it..on the top. He said, Sad... that one is healthy but will need to be taken out for the bridge. I don't get it. Why in the world would he need to take out a tooth from the top row above that tooth??? they are healthy up there

!!!
please, could you explain this to me???
thank you,
heather