there is no preparation. don't take any vitamin C supplements a couple days before your appointment. it is ok to use oil of clove on it for pain if u need to. it is also ok to use some oil of oregano. but, rinsing with warm salt water is best, several times a day (especially after meals). for the first 2 days or so, don't swish the water, just move your head side to side. you could use some amosan oral would cleaner, but i would try not to use it for a couple days or so (dilute it to half, tho; it is strong). u can find it at most drug stores. i hope that your dentist is not packing the cavitations with anything; it is not the best method for healing.