The oils in your previous runs had noticeably lower viscosities on less miles. So, you're telling us the 110,000 /9000 run with an ending vis of 8.52 started as a 40W vis?
Best to keep a natural tooth vs. an implant. Here's why: Your gum will not adhere to an implant causing food collection under the gum/ implant, future gum problems, etc., etc., etc. .02.
You gotta decide what you wanna do. Pull it or crown it? Down here, the root canal guys are specialists and the crown people can be general dentists. Anybody can pull a tooth, but, I would prefer an oral surgeon to pull mine.