What Is a Palate Expander and When Is It Used?

A palate expander is one of the most common interceptive orthodontic appliances and is used to correct bite problems. Learn more.
What Is a Palate Expander and When Is It Used?
Vanesa Evangelina Buffa

Written and verified by the dentist Vanesa Evangelina Buffa.

Last update: 05 February, 2023

A palate expander is one of the most common appliances in interceptive orthodontic treatment. It’s used to correct bite problems caused by a palate that’s too narrow. This oral appliance is used during childhood when the little one’s bones are still growing. Learn more in this article.

With these devices, it’s possible to guide and stimulate the development, size, and positioning of the jaw and widen the palate. This corrects the child’s bite problems and prevents more complicated conditions. In contrast, the persistence of a very small palate requires much more complex and invasive treatments in the future.

What’s interceptive orthodontics?

Before focusing on the characteristics of a palate expander, it’s important to understand what interceptive orthodontics is and why braces are used during childhood. This type of treatment is performed in childhood to take advantage of bone growth and correct malocclusions caused by bone problems.

Depending on the needs of each case, an orthodontist seeks to guide, stimulate, or slow the growth of the facial bones. For this purpose, different types of appliances are used, among them, palate expanders. By acting on the development of the jaws, the bones achieve an adequate size and position.

Applying interceptive orthodontics allows for the solution of bite problems in an early and simple way and, in this way, prevents them from progressing. It’s recommended during childhood, up to 12 years of age, when the stage of dental replacement is usually completed and bone development is stabilized.

What’s a palate expander?

An orange palate expander.
When the palate is very compressed, small, and domed in its center, a palate expander can enlarge it.

As its name indicates, this appliance allows for the widening of the roof of the mouth when it’s very narrow. It’s also known as a palatal expander.

There are several causes that can lead to a child’s palate not developing normally. Genetic factors, mouth breathing, and thumb sucking are some common reasons.

If the high-arched palate isn’t corrected, it causes problems such as dental crowding, crossbite, and discomfort while eating and breathing. It also affects the aesthetics of the smile and face. A palate expander helps the maxillary bone to increase its surface.

What problems are treated with a palate expander?

A palate expander can treat oral problems caused by an upper jaw that’s too narrow or too deep. As we told you, this may be due to genetic reasons or may have arisen due to harmful habits, such as oral breathing, thumb sucking, or prolonged use of pacifiers or bottles.

Having an ogival palate can cause different oral problems in children. These are the most common ones:

  • Crossbite: The upper jaw is very narrow and fails to fit correctly with the lower jaw. This causes some lower teeth to bite outside or in front of the upper teeth when closing the mouth.
  • Dental crowding: The lack of space in the jaw causes the teeth to erupt out of place, overlapping each other. Crowding of the teeth affects the esthetics of the smile, makes oral hygiene difficult, and increases the risk of cavities and periodontal diseases.
  • Tooth eruption problems: Sometimes teeth can block the eruption of a permanent tooth and prevent it from erupting. With a palatal expander, space is created in the jaw so that the retained tooth can come out without the need for a more invasive intervention.

Palatal expanders are also a useful treatment during the rehabilitation of children with cleft palate. These devices act as pre-surgical orthopedics and allow early development of the bony structures.

How does a palate expander work?

A palatal expander is placed over the child’s molars. It consists of two symmetrical components, made of acrylic or metal, joined together by means of a screw. This way, a determined force is applied to the maxillary bone to promote its growth and obtain an optimal size and shape.

Parents play a very important role in this process, as they’re the ones who activate the action of the appliance. The orthodontist will explain how to manipulate the expander screw and how often to do it.

How is a palate expander placed in the mouth?

When the orthodontist determines that the best treatment to solve the child’s bite problem is to use a palatal expander, they’ll follow the steps below:

  • Take impressions and make models of the child’s mouth to make the appliance.
  • Place the palate expander in the child’s palate and attach it to the upper molars.
  • Teach the parents how to activate and deactivate the appliance.

Active treatment lasts approximately 15 to 20 days. During this period, palate expansion will occur. After placement, it’s common for the child to feel some pressure in the mouth. In any case, these discomforts are temporary and disappear after a few hours of use.

During the palate widening, it’s common for diastemas or enlarged spaces between the teeth to develop. This shouldn’t be a cause for concern, as dental eruption or the use of fixed appliances in the future will correct the malpositions that arise at this stage.

Once the expansion time has elapsed, the appliance is locked in place and will remain in the mouth for 6 to 12 months. This is to ensure the stability of the results obtained. After this period, the specialist will assess whether a retainer is necessary or if the child needs to start a fixed orthodontic treatment with braces.

Orthodontic braces sitting on a table next to orthodontic tools.
There are several types of palate expanders made of different materials. These can be metal or acrylic and fixed or removable.

Types of palate expanders

There are different types of dental expanders. We’ll tell you which are the most commonly used designs.

McNamara expander

The McNamara expander is used in young children who are in the early stages of tooth replacement. It consists of two lateral acrylic planes, approximately 2 millimeters thick, which are placed on top of the molars.

Hass expander

This type of expander has a mixed support: It uses dental bands on the molars and has an acrylic plate that rests on the palatal mucosa and contains the screw. According to its proponents, it has a greater skeletal effect as it transmits the force more directly.

Hyrax expander

The Hyrax expander consists of two metallic planes that are kept fixed in the mouth by means of bands that are installed on the molars. It’s placed on the first premolars and on the first upper molars. Therefore, it’s useful when tooth replacement is more advanced.

Removable palatal expander

A removable expander is only recommended when the child needs a minor widening of the maxilla. These appliances are similar to acrylic expanders and can be taken off and put on by the patient.

Prevention’s the best medicine

Acting early solves problems in the mouth. Interceptive orthodontics can prevent malocclusions by acting on the facial bones as they grow. For this reason, it’s vitally important that parents take their children for check-ups with an orthodontist from the age of 6.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

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This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.