I had a TKR about 2 1/2 years ago and received somewhat conflicting advice going forward. The surgeon wanted me to take antibiotics before every dental cleaning or procedure where bacteria might enter the bloodstream and migrate to the knee. My dentist, on the other hand, did not think it was necessary. I've been cautious, perhaps overly cautious, so I do take antibiotics before each dental cleaning, but will probably stop now. You take the antibiotic a day before or the day of your dental procedure. Talk to your orthopedic surgeon and your dentist and get their advice if you haven't already. You (and I) are in an area where there isn't 100% agreement by the medical folks. I don't know why you would need to cancel needed dental treatment now as you probably had antibiotics post surgery and could take another course before a needed dental procedure. Good luck going forward.