If you recollect the moment when it was in pain and compare to the moment when it was absent then you cannot say that latter is not better than the former. You said that yourself that it is better. This feeling better is your sensation. Recollection of past sensation is sensation as well as far as mind is concerned.
Now when your teeth are not aching you can eat an apple or drink cold water. Or just meditate on the fact that they are in their present state. Pleasure can vary in kind but not in intensity or degree.