I had my right hip replaced with titanium about 4 years ago, but I don't think the surgery or any other medications I took through the surgery
and recovery have anything to do with my tongue
at this late stage.
I've continued the same medication (Indomethicin) for at least 6 years now, so I don't think that's the cause either.
I drink a lot of coffee and tea, and I was thinking that might be the cause; however, I've always drank a lot of coffee, so it doesn't seem plausible to me.