M.H.
She probably got used to waking up when she was sick, and now that she is better, she is simply just used to waking frequently. Since she was sleeping well before she was sick, she should be able to do so again easily (even through the teething). My suggestion is what our pediatrician recommened for my son at 4 months (although I wasn't tough enough to follow through with it until after six months). We used the Ferber method as suggested by our doctor. You can use this method with babies beginnign at 4 months.
Basically, it boils down to checking her when she crys at night, but not picking her up or soothing her back to sleep (you can pat her to let her know everything is okay) and then leave the room. You wait five minutes, and then check her agian, wait ten minutes, then check her again, and so on, increasing the amount of time between each check by five minutes until she goes back to sleep. The program stresses the importance of allowing your baby to return to sleep on her own, and once she gets used to that - poof, she is sleeping through the night again.
"Ususally" it takes about a week to work. With my son it took much longer, but he had NEVER slept more than two hours at a stetch by the age of six months. With your daughter having previously been a good sleeper, she would likely respond pretty quickly.
For eight months now, my son has slept for 12 straight hours every night (teething and all)!
There are other variations on this method, so you may want to research your options, and choose a method that you are comfortable with (I have also heard of "Sleep Easy" but am not familiar with it.)
Also, my son had problems with congestion at night (he was sick a lot). I felt that was what was causing him so much sleep difficulty. Our pediaterician said it was just a matter of learning to sleep through it. Well, he did! He has been sick and had congestion during the last eight months, but never once did it disturb his sleep now that he has "learned" how to sleep.
One last suggestion I have is keeping her bed time consistent, Like instead of "between" 8-9, choose a time, (I like 8:00) and stick to that time as strictly as you can.
You will probably get a lot of different advice on this subject and ultimately will have to do what you are comfortable with. And, every baby is different, so you may have to try a couple things before finding what works for you. Glad I could share what worked for me.
I just found a link to some "Ferber" info on Baby Center:
http://www.babycenter.com/0_the-ferber-method-demystified...
My pediatrician gave me a handout on it, and I bought the book. It seemd like a good approach, so I guess I never realized that there was any "controversy". I say talk to your doc at her 4 month check-up and research it before you make any decisions.