I think for the most part most pacifiers are designed to prevent damage to infant/toddler's teeth. I watch my 16 month old niece and she still uses her pacifier quite a bit to soothe herself. Personally, I wouldn't be to concerned. You don't want to rush her to get rid of the pacifier. She may pick-up a new habit like thumb sucking that can damage her teeth.
Also, I don't know if this applies to toddlers, but I wanted to share what I was told about my son. My son is four years old and he is so different with my husband and I than he is with everyone else. I get so many compliments on how polite, helpful, and nice he is. Some days I want to ask.. "are we talking about the same boy?" I was told that this is a good thing because it means they're comfortable enough at home to be themselves. It, also, means that they KNOW how to behave properly and actually do it. However, she is much younger so, she may just know that you'll let her act "younger" than at her daycare. We, Moms, tend to want to baby our li'l angels a bit. At the daycare, she is with a group of other toddlers her age and is forced to be more independant. Again, I'm no expert. I just thought I'd share what I was told. I hope it helps!
Smiles,
E. B