It depends on the age of the child. If they are young, I would usually tell the parents that you just have to do it. It's good for them. It is like getting a vaccination. When they are older there are other ways like using electric toothbrushes and putting stickers and sort of making it into a game, but in the end, the parents still have to check and supervise.
In fact, a lot of times, these appointments are squeezed in during school. Sometimes parents might be stressed, but the thing we usually do is treatment and the child might have never come in the clinic before, making it hard for us as we do not know what the parents promised the child and when we break the promises, it’s hard to rebuild the trust.