I've been using it when she gets fussy and she seems to love it. Is this a bad habit to get into? I've heard there are potential dental/breastfeeding/dependency issues. Is there any truth to this?
One cause for concern is nipple confusion. Essentially:
Not all children get it (mine didn't), but I've had friends whose kids have definitely had issues with this. This article discusses the timing of introduction of the pacifier and the bottle. The article is lengthy, and also discusses bottle feeding vs. breast feeding (germane, as the problem is nipple confusion, which can arise here as well). Her final recommendations with bottles (unless you have to supplement feeding) are:
EDIT: Also, in case you're worried about potential effects later in life (ie, the possible need for braces caused or exacerbated by the use of pacifiers or bottle feeding), there does not appear to be a statistically relevant link, according to this study. From the abstract:
When they're infants? Nah. When they're three? Yes!
Your pediatrician will keep an eye on the baby's physical development in their mouth, and should let you know when they've been using the pacifier too long.
When babies can learn to self-sooth, they are a lot of the way along to learning a skill that's vital for falling back to sleep without help. Even if they don't always use the pacifier at bedtime, they will have learned that they don't always need your help to calm down. Yay!