Orthodontics 101: What is a Crossbite?

Crossbite. It’s perhaps not as well-known as issues like an overbite or underbite but it’s equally a problem when it comes to oral functioning, health, and aesthetics. 

That’s why we at Foundations Orthodontics want to take a moment to answer the question, “What is a crossbite?”

If you think you have a crossbite, read on to learn what it’s all about and how your orthodontist can help.

We’ll cover:

What is a crossbite?

Crossbites fall into the same group as overbites and underbites: a type of malocclusion — or dental misalignment — where your upper and lower teeth don’t stack properly together. As described by the American Association of Orthodontists, a crossbite is where upper teeth sit inside your lower teeth. 

Doesn’t this sound like an underbite, you ask? We know, it’s easy to get the two confused; the difference is that a crossbite is only a few teeth sitting inside the lower teeth while an underbite is the entire top arch sitting inside the bottom one. A crossbite can involve only one misaligned tooth or groups of teeth, and sit at the front, back, or side of your dental arch. 

On the other hand, a well-aligned bite has teeth lined up so they fit and stack together well. The upper arch is slightly wider than the bottom and all the upper teeth will sit slightly outside the bottom (both not so much that it turns into an overbite).


Different types of crossbites

Crossbites come in two types: an anterior crossbite and a posterior crossbite. Let’s talk about each of these below:

Anterior crossbite: “Anterior” means “front” so if you have an anterior crossbite, you have one or more front teeth sitting behind the front bottom teeth. These teeth include the upper incisors and canines. In some severe cases, the lower front teeth completely hide the upper front teeth.

Posterior Crossbite: This is the opposite of an anterior crossbite. “Posterior” refers to the back teeth, so if you’re diagnosed with an anterior crossbite, one or more of your upper back teeth — your molars — sit behind your lower back teeth. 

Posterior crossbites typically happen because the upper jaw and palate is very narrow.


What causes a crossbite?

There’s more than one answer when it comes to the question, “What causes a crossbite?” Causes of both posterior and anterior crossbite include:

Genetics

The most common reason for crossbite teeth is genetics. Perhaps you’ve noticed that your parents, grandparents or other family members have orthodontic issues like a smaller upper jaw and a larger lower jaw. Or a narrow palate and misaligned teeth. Crossbites can happen in these situations once permanent teeth start to erupt.

Delayed eruption of adult teeth

Sometimes a crossbite is the result of abnormal dental development in childhood, like if baby teeth take a longer time to fall out and prevent permanent teeth from growing in properly.

Unhelpful early childhood habits

Going back further, a crossbite can occur because of infant oral habits that continued into the toddler or early school years: Prolonged thumbsucking or fingersucking, excessive bottle or pacifier use, tongue thrust, or swallowing in a certain way can result in pressure that pushes teeth into a crossbite and distorts jawbone shape.

Mouth breathing

Breathing through the mouth when you’re sick or because of seasonal allergies is one thing. Persistent mouth breathing from more serious underlying issues is another. For children, the latter can turn into a laundry list of oral issues like crossbites, as well as physical and cognitive problems. 

How? Mouth breathing can alter normal facial development, contributing to misaligned jaws that can lead to a crossbite. And if a child has a small upper jaw already, there’s a higher chance of developing a crossbite when they’re adult teeth come in.


Complications that result from crossbite teeth

Whether a front crossbite or back crossbite, this type of misalignment can bring about many oral and overall health issues. For some of our patients, a crossbite even significantly impacts their quality of life. That’s why if you suspect you have a crossbite, we suggest you see your Denver orthodontist sooner than later.

Complications that result from crossbite teeth
Some of the complications that can arise from crossbite teeth include:
  • Cracks or chips in teeth from occlusion between your upper and lower teeth
  • Increased risk of cavities
  • Gum disease that can lead to bone loss
  • Receding gums, again from occluded teeth sitting or rubbing against each other improperly
  • Inability to close your mouth fully with your lips together
  • Pain or difficulty when chewing or biting
  • Headaches and jaw aches
  • TMJ pain
  • Serious toothaches
  • Wearing down of your tooth enamel
  • Poor sleep
  • Speech issues
  • Low self esteem

If left untreated in childhood, crossbite in a child can lead to the jaw shifting to one side during development, a lopsided jaw, and an asymmetrical face shape as an adult. These issues are harder to fix later in life versus during childhood, when the facial structure is easier to manipulate.

How to fix a crossbite 

A crossbite needs orthodontic intervention to correct, it’s not an oral health issue you grow out of or that corrects itself over time. In fact, it typically gets worse the longer it goes untreated. As bite correction experts, Dr. Moran and Dr. White can fix your crossbite and give you a new lease on life.

Every patient’s path to a crossbite-free smile is different since everyone’s teeth are unique. But what’s the same about every crossbite case at Foundations Orthodontics is that everyone receives a personalized treatment plan from a holistic approach. This all-encompassing focus means Dr. Moran and Dr. White design a smile in harmony with the whole face, with a strong, stable bite that functions as it should, and teeth that look amazing.


Crossbite correction in children - with braces

Fixing crossbite teeth in a child typically involves treatment with braces. We offer both clear and metal braces for crossbite treatment at Foundations Orthodontics. You might like to know that braces on their own can correct a crossbite when here’s only a single tooth or just a few. However, severe crossbites may require using a palatal expander as well. 

What is a palatal expander? A palatal expander is an appliance that sits against the roof of the mouth and is secured there with wires attached around the molars. A tiny screw is turned everyday to incrementally expand the upper jaw, which, for kids, responds well because the upper jawbone is still in two halves during childhood. These halves eventually fuse together by adulthood, making maxillary expansion (widening the upper jaw) a longer process.

Because movement is so gradual with a palatal expander, kids don’t feel much discomfort, if any at all. The result? A wider upper jaw that situates crossbite teeth outside the lower jaw instead of inside it.


Do clear aligners work for a crossbite?

To put it simply, yes. Aligners can work for crossbite cases, but typically milder ones. Many of our adult patients prefer clear aligners because they’re discreet and offer minimal change to your daily life. 


Surgery for a crossbite

More severe cases of crossbite in a child, teen, or adult might require surgery. Orthognathic surgery — any surgery to correct malocclusion from a misaligned bite — is typically paired with braces or clear aligners to complete treatment. Orthognathic surgery procedures achieve a variety of movements for the upper jaw like moving it forward, backward, or even widening it. Procedures can also move the lower jaw: rotationally to correct asymmetry, forward, or backward.

Typically, your orthodontist is the one who refers you to a surgeon to discuss jaw surgery. It becomes part of your overall crossbite treatment plan and a big step in your journey towards an aligned bite that’s healthy and beautiful.


How long does crossbite treatment take?

As with all orthodontic treatment, the time it takes to achieve crossbite results varies from person to person. Treatment time depends on the patient’s age and the severity of their crossbite. For kids, crossbite treatment is often fairly quick because their jaw is still developing and bones are softer and easier to manipulate. Fixing crossbites in adults takes more time.

Correcting a front or back crossbite with braces typically takes between six months to two years. If jaw surgery is part of your treatment plan, your crossbite correction will be longer, especially including your recovery time.


How much does it cost to fix a crossbite?

Because treatment plans vary, so do costs. The good news is that orthodontic insurance can help lower your out-of-pocket investment in your smile, especially if your crossbite has had a serious negative impact on your daily life. 

On the way to a crossbite-free smile with your Denver bite specialist

Bottom line, the certified bite specialists at Foundations Orthodontics have you covered. We’ll help you say goodbye to a crossbite and hello to a strong, stable, and stunning smile. You’re in expert hands with board certified orthodontists, Dr. Renee Moran and Dr. Caitlin White. 

Make an appointment at one of our four Colorado locations: Denver, Granby, Winter Park, or our newest Homestead Park office in Centennial.

Renee Moran