I am far from an expert on dentistry and pacifier usage, but I think that at some point pacifier usage causes abnormal development of the palate and of muscular function. Granted, I don't know the extent to which it happens, at what age, how reversable it is, and how many hours of usage per day is of concern. However, if this is something that you are already thinking about, you may want to do some research to see what you think about the studies that have been done in this area--I think there are a lot. Good luck! I know I feel better about a decision when I have at least read the academic studies on the topic, even if I end up not going along with what was "decided".