Hi, I got a 12 unit bridge recently on top teeth. Any suggestions?

My question is had a impacted canine in left top. That too with some decay in it. And I had two gaps in front teeth.it was permanant gap. So my orthodontist told me to extract canine. And place bridge from canine to canine.. After removng my canine doctor told me I have bone loss in that area so it got a holow part like a ridge.. Now bridge is fixed and that area is covered with gingivia like material,.My doctor told this is normal some patients gets bone loss. Is it so?