C.A.
I don't know much about breastfeeding, but I would assume she won't wean herself unless she learns how to put herself to sleep. You could try to to get her a lovey or something to help her fall asleep, my daughter has a stuffed bunny that she couldn't sleep without. Does she sooth herself back to sleep when she wakes up? Have you tried putting her down sleepy but awake?
My pedi dds said that kids who get cavities before they are 2 or 3 have to be sedated to have them taken care of. You (we) should brush their teeth before bed and not give them anything to eat or drink (breast milk included I'm assuming because it's on the teeth) and start flossing as soon as the teeth start to touch. I personally found it very valid because I don't think I would handle my daughter sedated very well =O)
Best of luck!
C.