Swords Orthodontics
17 Main St, Swords, Co Dublin, Ireland

What is a Crossbite?

The two crossbites we see the most here at Swords Orthodontics are Incisor crossbites and Molar crossbites.

Incisor crossbite before

Incisor crossbite after

Is it common? The rate of anterior crossbite is 4 to 5 percent according to the Contemporary Clinical Dentistry Journal (2013)

Causes: Usually developmental, but could be as a result of trauma/injury

Presents as/What to look for: The upper front teeth (incisors) sit behind the lower front teeth

Complications: The result of an Incisor crossbite is a bad bite also referred to as malocclusion. This means the teeth are not meeting correctly and that the bite is misaligned. This can result in other dental problems. It is particularly serious if the crossbite is associated with an interference in how the teeth close and the lower jaw closes in a position that isn't right for it. Sometimes a crossbite can cause abnormal wear on the front teeth.

What are the interceptive methods? Wearing a removable or fixed brace to push the upper front teeth in front of the lower front teeth.


Molar crossbite before

Molar crossbite after

Is it common? According to Cochrane:’Orthodontic treatment for posterior crossbite’ (2014)The condition affects between 1% and 16% of children who only have their baby teeth. Most posterior crossbites (50% to 90%) remain even when the permanent teeth erupt”

Causes: Genetically narrower upper jaw than lower jaw, or teeth developing and then erupting in the wrong position

Presents as/What to look for: The upper teeth or jaw are narrower than the bottom teeth and when they bite down the top teeth sit down inside the bottom back teeth. This is particularly a problem if it causes the lower jaw to shift sideways when the teeth close together.

Complications: Cochrane(2014) states ”In order to obtain a more comfortable bite, the lower jaw shifts to one side into a position that allows more teeth to come into contact. However, this shifting of the lower jaw may lead to tooth grinding, and this may lead to other dental problems including the tooth surface being worn away, abnormal growth and development of the teeth and jaws, and jaw joint problems.”

What are the interceptive methods? The use of a Rapid Maxillary Expander (RME) or a removable expander to widen the upper jaw and then wearing braces.

If you notice you or your child has one or both of these crossbites don’t hesitate to call us on 01 810 7622 for a free consultation with one of our Orthodontic specalists.

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As part of Phase One of the National Reopening, Swords Orthodontics is now resuming routine orthodontic treatment.
There will be a few differences in how we do this specifically to deal with coronavirus, but you'll still be getting great orthodontic treatment.
We'll be in touch to reorganise your appointments, please don't attend without an appointment.