This is probably one of the age-old questions that until the advent of modern dentistry could only be answered by our great-grandmother's old wives' tales. Today we are better able to determine the answer to that question with greater detail on the why and why not's.

So, is thumb-sucking good or bad? The quickest answer to the question? Yes.

Wait, what?

Starting with infants

According to the American Dental Association, thumb and finger-sucking is a very natural habit for infants. The behavior often starts in the womb, as prospective parents sometimes find in their sonograms.

Thumb-sucking is an instinctive reflex that gives your baby comfort and helps them feel secure. This behavior develops into a coping mechanism to aid them as they learn to deal with anxiety and separation, which can be a great tool when you are trying to get them to go to sleep.

Use of this coping mechanism will continue as they grow into toddlers and find themselves exposed to new environments, activities and people on a daily basis.

So, for infants and toddlers, the answer is "Yes, it is good for them."

Preschool age

We all know that as a child gets older, parens should discourage them from relying on a thumb or pacifier. And while some parents are fortunate enough to have a child that loses interest by age two, others will find themselves battling over the subject all the way into Kindergarten when peer pressure usually solves the issue.

So, how old is too old? The American Dental Association determined that by age four or five, it's best to find a way to stop your child from sucking their thumbs or using a pacifier.

Once the permanent teeth erupt, thumb-sucking has been known to produce issues in the ideal growth of the mouth as well as the proper alignment of the teeth. The habit has also shown to cause changes to the roof of the mouth and its shape.

Watch your child's habits closely. If he or she is merely resting their thumbs passively in their mouths, this will have less of an effect as those who suck actively or vigorously.

So, for older preschool ages and above, the answer is "Yes, it is bad for them."

How can I make them stop?

Just like any other habit, especially one developed as a coping mechanism, thumb-sucking can be challenging for a child to stop.

The Mayo Clinic advises parents on what to look out for and provides steps to assist your child in breaking the habit before it becomes a problem. You can start by talking to your child about the practice. There is a better possibility of success if your child understands why they need to stop, and is allowed to be involved in the method applied.

In other situations, ignoring the habit can be enough. Doing this is useful in cases where the child has established thumb-sucking as a way to get your attention.

Other options include:

Gentle reminders

Most of us have formed certain habits without realizing it. If your child sucks his or her thumb unconsciously, it's best not to be critical when addressing it. Just gently remind him or her to stop. You don't want an unconscious habit to convert into a trigger habit.

Identify their triggers

For many children, the habit developed as a comforting reaction to stress. If you can identify the issues that lead to the behavior and provide comfort in other ways, you will remove the need for thumb-sucking altogether.

Positive reinforcement

Offer praise or small incentives when they choose to stop. These could include such rewards as extra bedtime stories or a special outing. Keeping track of their progress with stickers on a calendar will show them how well they are doing and encourage them to continue.

If you have growing concerns about the effects of thumb-sucking on your child's teeth, talk to your dentist. In fact, for some children, hearing why it's important to quit the habit from their dentist is all it takes. It's also sometimes more effective than hearing it from mom and dad.

If thumb-sucking becomes a problem to the development of their teeth and mouth, your dentist can recommend a mouth guard or similar product that impedes with sucking.

What if nothing seems to work?

For some children, thumb-sucking will be as challenging to stop as smoking would be for an adult. If this happens, you may need to let nature take its course. Putting too much pressure on your child to stop will only increase the anxiety that the habit helps alleviate, and will end up delaying the desired result. Eventually, peer pressure leads most older children to stop.

Remember each child is unique and develops at their own pace. So don't worry if your child takes longer to wean off the pacifier; with your help and encouragement, they won't need it soon enough.