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Causes of changes to your bite – It’s more than you think! Part 4

August 17, 2026

Open bite caused by thumb sucking - 4 year old

Changes to the bite can start very early in life. The bone of a young human is very malleable. The teeth just going along for the ride.

You see the thumb is mightier than the bone! (Sometimes fingers have a go too).

Yes, a persistent child can alter the bone in BOTH jaws, the teeth, its growth pattern, shape of face, speech, mouth breathing, swallowing and yes even the bite. A bite that has no bite on the front teeth.

Thumb sucking starts in the womb. It continues once the baby is born as it reminds the child of the mum’s nipple. The problem arises once teeth start to come through after six months. Persistent thumb or finger sucking becomes a comfort habit which can be hard to break as the baby gets older. Babies’ bones are very malleable during their development. The upper jaw, the maxilla, in early develop has a front section called the pre-maxilla. This disappears with age, but thumb sucking can cause it to change shape, and be molded more forward to the normal arch of the teeth.

But there’s more. We have man-made device that that gives the thumb and fingers a run for their money.

I give you the dummy.

Anatomical dummy

A dummy is often used to help a child go sleep or as a pacifier. An anatomical dummy is usually better suited to the shape of the mouth. However, there are few things that need to be avoided with dummies.

Do not put the dummy into your mouth then into your baby – it’s dirty! They will inherit your bacteria and any infections you have AND visa-versa. This is not the time to share the love. A family can get very sick very quickly.

NEVER PUT ANY SUGARY SUBSTANCES ON THE DUMMY. This is a recipe for dental and dietary disaster. The bub will crave for sugar and will have decay in their new teeth to show for it!

Prolonged use of dummies can lead to the same problems as thumb sucking.

If the habit is stopped early enough then the child’s growth can often correct the effects of a dummy. The earlier it is removed the better. The very latest is 5 years old but even then, is habit that has to be broken, i.e. before the permanent teeth appear.

The advantage of a dummy used for getting a baby to sleep is that it can be removed. A thumb is a bit more difficult.

How to get rid of it!

Get four or five dummies. Pierce a hole in one dummy with a pin. The next dummy pierce more holes. Then the third dummy bigger holes. The fourth dummy bigger holes then the final dummy cut the top of it.

Give the baby the first dummy. When the baby finds the suction is not as good, and throws it away then give him/her the next dummy with more holes. And repeat the process till the final dummy which has no suction. By this stage the baby will be frustrated with the use of a dummy.

Then if all goes well, bye bye dummy! Hello, hopefully, a good bite!

Dummy pierced by needle to reduce suction

Next in Series: Causes of changes to your bite – It’s more than you think! Part 5 – Bone Growth issue

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