Periodontal Disease: What is the Better Option a Bridge or a Dental Implant?

I have periodontal disease and am in the process of undergoing the deep gum cleaning. I recently had to have a bottom molar #19 extracted, because it was broken underneath the gumline. My periodonist said that within four or five months, after getting my gum disease under control, she would refer me an oral surgeon, to replace the tooth with a dental implant. Alternatively, my periodontist told me that I could replace it with a bridge. It was up to me. My question is, given my periodontal disease, what is the better option for me, and implant or a bridge? If I go with the implant, and if it fails, would I have another options afterwards ? I have read that if a implant fails, you cannot replace it with a bridge later.