Expanders - Braces R Us

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Twin Falls

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(480) 668-8200




Date: October 19, 2023

Expanders are a commonly used orthodontic appliance. All expanders widen the semi-circular arch the teeth form. This creates space to alleviate crowding, and also creates a fuller, more pleasing smile, enhancing the esthetics of the overall treatment result.

Expansion is used in orthodontic treatment for a number of reasons. There are a number of developmental, environmental, functional, or growth discrepancies that can create a need for expansion as part of an overall treatment plan that addresses a patients’ orthodontic needs. Sometimes the teeth are collapsed inward towards the tongue, other times the jaws are narrow, or the problem could be a result of both the teeth and the jaws being narrowed. If the upper or lower teeth, or the upper jaw, need to be widened, an expander may be indicated.

There are expanders for the upper teeth and jaw, as well as expanders for the lower teeth. Expanders can be removable, or they can be “fixed” or cemented in place like the braces. Some expanders are designed to widen the upper jaw, and others are made to widen the semi-circular arch that the upper or lower teeth follow. The goal of all these expanders is to correct a width deficiency in the upper jaw, or the arch the teeth follow.

Expanders have several names. These orthodontic appliances are often just called expanders, but are also known as RPE’s, MSE’s or by other acronyms, as well as some designs being named after the doctors who invented the appliance, like the Schwarz appliance. Because there are a variety of problems that need to be addressed in orthodontic treatment, there are a variety of expander appliances. Each style of expander appliance provides expansion, but expands in a different manner or provides another function in addition to the expansion.

There are two types of expansion; dental and skeletal. Both the upper and the lower teeth can be expanded, but only the upper jaw allows skeletal expansion. Dental expansion is often referred to as “arch development” because the dental arch is expanded and a more natural arch form is developed. Generally speaking, removable expanders are as effective as fixed expanders at achieving arch development. For skeletal expansion, it usually requires a fixed expander to widen the upper jaw.

With dental expansion, or arch development, an expander appliance is not always needed. At times, arch development can be achieved with the braces. However, an expander may provide additional benefits or a more predicatable outcome in some cases, so not all arch development is done with or without an expander. The manner in which arch development is achieved depends on the individuals needs and what the treating orthodontist determines will be best suited to the patient and their individualized treatment plan.

For skeletal expansion of the upper jaw, there are expanders that attach to the teeth and there are variations that attach directly to the bone via small skeletal anchors or TADs. These appliances are generically called MARPE’s, and are especially helpful in getting skeletal expansion in adults and nongrowing teenagers. This is an exciting new development in orthodontic treatment because it allows for potential skeletal expansion in adults, where previously it required a surgical procedure to expand the upper jaw. Surgical expansion may be avoided with a MARPE, provided the upper jaw responds in a normal fashion.

Expanders widen the semi-circular arch the teeth follow which makes space to alleviate crowding, in addition to creating a fuller, more pleasing smile. Expanders are a wonderful appliance that helps the orthodontist improve the patients appearance, smile, bite, function, and oral health.

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