I have 4 consultations through implantologist, oral surgeon, 2 cosmetic dentists around my broken front crown( the front tooth already have had a root canal long time ago) The very kind specialist of implant doctor told me that because of the front tooth and for the esthetic reason implant is not an option( I have a little bit of a gummy smile) he suggested to place the bridge instead and not o extract the remain tooth out to avoid the future gum collapse. Is it safe o leave the remaining tooth?