Asking some children to give up a pacifier is like getting an adult to quit smoking. Oral gratification is an instinctive human relaxation behavior that calms everyone from thumb-sucking fetuses to gum smacking colleagues. Smoking, pencil chewing, and snacking are all iterations of this self-soothing technique. It's a tough behavior to change, but pacifiers can be a costly habit in the form of orthodontic bills later on.
According to the American Dental Association, "Children who continue to use pacifiers past the age of three show a higher prevalence of altered dental arches and abnormal lip and cheek mobility compared to those who never used a pacifier." After 18 years of pediatric dentistry, Dr. David Snodgrass, DDS, recommends ditching the binky between 14 and 16 months of age, "We've found that the best way to get the children off the pacifier is to simply place every one of them in the house in a plastic freezer bag, shake them in front of the child, and tell them they are going to take them to their pediatrician (or Dr. Snodgrass) so he can give them to the little babies at the hospital. The next time the child asks for them, blame it on me."
Other parents recommend trading the old pacifiers in for a brand new toy or throwing a Pacifier Party complete with cupcakes and streamers to say goodbye to their dear old friends. Another way is to gradually cut back on the nipple size by snipping a little off each week. This worked like a charm for my kids because they still got to hold their precious pacifiers—nothing was taken from them—they just couldn't seem to keep them in their mouths for more than a minute because the suction breaks when your snip off the tip. It's almost the same as someone tuning your television to only broadcast the weather channel: you still have a TV and it still works, but it's so boring that you quit watching it after a few minutes!