Mu little girl will be 3 in 2 days and I also see no end in sight for nursing. I nurse at bedtime and then am in her bed during the night although I try to refrain from nursing until after 4am - she seems to wake up less if she does not fall asleep on the brest at 1-2am.
She also needed teeth filled, but I was told it was not due to cavities, but rather due to the fact that the enamel on her teeth did not form properly. My dentist said not to worry about breastfeeding still - very comforting as I know not many dentists will say that.
So I guess I have no real advice other than only stop if you feel you need to, and not because of his age or society beliefs. There are many societies where it is normal for kids to be breastfed to 5 or 6 years old.
I stopped day feeding by talking about it with my little one and limiting the times of the day she could have it (nap time & if she hurt herself) then we moved onto saying that during the day she does not need it and can drink milk or water, but can get cuddles whenever she wants (and some days it is alot). Although she normally does not ask for it during the day occasionally she will ask for it becasue she is tired or sad, but mostly we are able to distract her with a game or something else instead.
I also started wearing clothes which made accessing the breast difficult to impossible (dresses, normal bras etc) and told her that Mommy could not get to them right now and would she like something else (milk or water) and she can have a feed later.
It did not take long to drop the day feeding, however there is a huge attachment to the night feed and like you when the time comes I am wondering how it will be done. However, I am in no rush to force it before she is ready.
Good Luck! :)
K.