I would call Demerol comparable with the Percocet, maybe a bit stronger. It should keep you very comfortable. When I have kidney stones I am usually given Demerol through IV in the hospital and then sent home with the Percocet 10 mgs. They usually give me equal relief. The Demoral is, however, a very euphoric drug, especially through IV. Many hospitals are going completely Demoral-free for that reason. So enjoy your hospital stay.
For the answerer above me, you are incorrect. Demorla is an opiod. It is completely synthetic. Percocet is an opiate, it is derived from Thebaine which is one of the alkaloids of the opium poppy. Percocet is a very strong narcotic and should not be taken lightly. The very same medication that is in Percocet is in OxyContin. It can be very dangerous and addictive if used improperly and should not be dismissed lightly. And, just as an aside, the pain from wisdom teeth removal and especially shingles can be extremely severe.