I agree with you @cstucky about erring on the side of caution. I am especially concerned because my cousin has lived for years without a hip after chronic MRSA set in.
My very respected orthopedic surgeon explained it this way: We know the risk is low for joint infection, but it is not zero. We know the mouth can be a vector for many infections, especially if you have periodontal disease or an abcess. We know the antibiotics are quite safe as a preventive measure. We also know joint infection, if you get it, can be devastating. So I recommend prophylactic antibiotics permanently.
My dentist happens to agree. I see them like other health practices, like hand washing, masking & vaccination - giving me the best chance to remain healthy.
Sue