Does Thumb Sucking have Long-Term Effects - by Dr. Kathryn Jones


At first it seems relieving when your baby finds his/her thumb! The peace and quiet that follows is welcoming, but what are the long-term effects? Between the ages of 2-4, most children will stop sucking their thumb thanks to learning new ways to self-soothing and a little social pressure. However, each child is different and so is their habit. Some children suck vigorously and often, while other children are gentle and infrequent. thumbsucking

What is an Open Bite, Overbite, Underbite?
A dental malocclusion is an abnormal meeting of the upper (maxillary) and lower (mandibular) jaw, or tooth misalignment that is visible when the mouth is closed. A malocclusion can be present at birth or is the result of habits such as thumb sucking. Children’s jaws are soft and growing rapidly so it is easy to understand why this happens.

Open Bite happens when the top and bottom front teeth move outward and do not touch when the mouth is closed.
Overbite happens when only the top front teeth move outward. The top teeth cover the bottom teeth when the mouth is closed.
Underbite happens when only the lower front teeth move outward. The bottom teeth cover the front teeth when the mouth is closed.

How does thumb sucking affects tooth alignment?
The pressure of thumb sucking can alter the growth of the mouth and alignment of the teeth by pulling the jaw joint out of position. If stopped early enough, the shape of the mouth and jaw, and alignment of the teeth will self-correct. That’s why it a good idea to schedule your first dental appointment at one year or the appearance of the first tooth.

Tongue Positioning Changes and Speech Impediments
Thumb sucking can keep the tongue positioned in different angles or lowered in the mouth, preventing the natural upward transition, resulting in a tongue thrust. This is a behavioral habit of placing the tongue in the wrong place during swallowing, speech, and resting. Sometimes it protrudes through the front teeth. Frequent thumb sucking means that babies have fewer opportunities to practice forming words with their mouths, which can impede the oral motor skills needed for speech. Since tongue muscles don’t develop correctly, sounds like “s” and “th” are difficult.

Is there a stop date to set?
Most children stop thumb sucking between the ages of 2-4, or when their permanent teeth start to appear. Once their language develops and communication skills assist with comfort and coping skills, thumb sucking usually fades. The general rule is to stop when the permanent teeth arrive. Now research indicates effects can have an impact at a much younger age, so a stop date should be around 3 years. 

Best Practices:
Don’t use harsh words or get frustrated.
Praise your child for not sucking their thumb
Involve your child in choosing to stop.
Ask your dentist to explain the effects of thumb sucking to your child.