Hi N. -
Have you read some of the responses from Trena V's pacifier question? Although your children are different ages, I think much of the same concern is there.
I allowed my children to have pacifiers until they were one, however, it was my mother who really got them over their dependence by making them quit cold turkey. It was hard on our entire household for about a week, but once they were weaned, it was a glorious feeling not to be slaves to their "pacies." No more fretting about the whereabouts or sanitizing them when they dropped on the ground, or buying them late into the night because they disappeared somewhere in the house. My mom was absolutely right in telling me that WE depended on their "pacies" and needed them more than our kids did because it was a quick fix to keep them quiet.
What many moms don't realize and are resentful about is that pre-schools and daycares don't allow pacifier usage because they are trying to encourage children of that age to become independent and less reliant on objects that provide false security. A pacifier or blankie or stuffed animal is not going to provide the safety, security, or confidence that a human being will do (i.e. parents, teachers, etc.). Most importantly, however, children need to eventually learn how to comfort themselves by going through a little anxiety and working through it with parental and/or teacher guidance - not temporary comfort from inanimate objects.
Many of my own friends anguish over the fact that their two-year olds aren't speaking at the level they should be because their kids would rather just rely on the comfort of the pacy rather than trying to express themselves with actual words. Concerns about proper dental growth are valid (I don't know ANY dentist who would advocate pacifier usage after age one), however, I think most importantly, giving up the pacifier is foremost about encouraging independence. After all, we don't want our children growing into needy, insecure adults. Now is the time to encourage your child to "self-soothe," and while it may be difficult at first, the pay off is their independence and what a great feeling that is for everyone around! Blessings to you and yours.