My dd wakes at night usually only if she is having some difficulty with her teeth, or is starting to get a cold. I have found that the 2 year molars are the worst. My dd is currently working on her last one and she has been waking up screaming! I usually know that she is having some teething troubles b/c she steals LO's paci - right now her last one is coming through - If she wakes like that, and I suspect that she is teething, I will giver her some Advil or Motrin. Usually gets her through the rough patch.
Hope that helps.
L