As the dentist does accept AMEX, you can earn more points by not doing the health fund rebate in the surgery, but putting the whole amount on the cc. That way, you will get all the points and the shop small discount.
Good point.
I did think about paying in full but only had 5 amex cards so no more credits and today I was happy to forego the points on the rebate in order to get it over and done with (very stressful fitting in dental emergency into an overfull day). But yes best to pay in full and then claim.