If using a pacifier, try and restrict its use to when your baby seems to need the self-comforting behavior of sucking. Avoid using it every time your baby cries (it is usually better to pick and hold your baby to comfort him when she is crying) and to be safe, use a one-piece commercial pacifier and do not hang it around your baby’s neck. Also try and avoid allowing your infant to get into the habit of falling asleep with a pacifier, since she may wake up when it falls out and cry until you put it back in her mouth.

After six months of age, you should restrict pacifier use to only when your baby is in her crib so that she begins to lose interest in it.

While it is usually recommended that you try and wean your child from thumb sucking or using a pacifier around the time they are six to nine months old, many children continue sucking on their thumb or pacifier and don't stop until around their third birthday. This has recently been associated with an increased risk of ear infections. 

If your child has not stopped by her third birthday, you should consider taking action to stop this habit if she is sucking on her thumb/pacifier for most of the day, if it is affecting her communication or social skills, if she is having trouble with her pronunciation of words, or if it is causing problems with her oral development. It is not as important to get your child to give up this habit if it is not causing any problems.

Some tips to help your child give up sucking his thumb or pacifier include:

• offer a reward or special treat to give it up. Star charts are a good way to track progress.
• give her lots of praise and attention when she is not sucking her thumb or pacifier
• begin to limit thumb/pacifier use (first limit use to inside the house, and then put the kitchen off-limits, etc.)
  take the air out of the pacifier by poking a hole in it or cutting off the end
• replace the comfort of sucking with other comforts (for example, holding her hand when she upset)
• supply a substitute and keep her mouth busy by singing a song, playing a musical instrument or having a snack
• most importantly, ask your child about giving up sucking her thumb or pacifier and how she would like to go about doing it (slowly vs. cold turkey).
  

Avoid putting your child down or describing her as being ‘babyish.’ Also avoid nagging your child or turning this into a power struggle. The more anxious she becomes, the more likely she will need the comfort of her pacifier or thumb.

If your child is motivated to stop, then placing something on her thumb to remind her that she is about to suck her thumb may be helpful. This is really only useful as a reminder though, since she can easily take it off.

A Pediatric dentist can also install in oral appliance that makes it uncomfortable to suck her thumb and relieves pressure on the teeth and palate. This is important if her thumb sucking is affecting her oral development.