What Is The Role Of The Jackscrew In Rapid Palatal Expanders?

One of the most common orthodontic appliances that is prescribed by orthodontists is rapid palatal expanders (RPE) that will create more space in the child’s mouth so that the teeth will grow straighter and more comfortably. Lack of space in a child’s mouth can result to cross bites or overcrowding and requires orthodontic treatment.

The standard palatal expander has two primary components, the framework and the jackscrew. The framework is used to secure the appliance to the teeth, tissue or palatal bone while the jackscrew provides the activation for rapid expansion.

The first time that jackscrew expander was used dates back to 1860. Angell’s case report was published in the Dental Cosmos, the first national journal of American dentists. Angell’s patient was a 14-year old girl suffering from ectopic left canine and posterior crossbite. A unique transpalatal appliance was fitted on the girl’s mouth and rested against the premolars with two counter-rotating screws.

Angell gave a key to the girl with instructions to turn the jackscrew to ensure that pressure is uniformly tight. The girl returned to Angell’s office after two weeks with the crossbite corrected and the arch widened by one-fourth inch. Angell also noticed the presence of median diastema, a sign that the maxillary bones have separated.

Unfortunately, Angell’s theory of sutural separation was rejected by the Dental Cosmos Board and he was censured by other professional dentists at that time. The rapid palatal expansion technique was abandoned.

In 1960, the jackscrew expander made a comeback with Haas RPE that featured a modern jackscrew that was made by Dentaurum. The RPE became a routine orthodontic treatment and other frameworks were introduced.

Most orthodontists prescribe customary 30 turns of jackscrews among patients suffering from moderate to severe overcrowding. The common jackscrew made from stainless steel alloy can provide 10mm of expansion.

It is important for parents to bring their child to an orthodontist if the mouth is too small to allow teeth to grow comfortably. While overcrowding does not cause pain, it can make eating and talking difficult. Orthodontists will prescribe the palatal expanders if the upper jaw is smaller than lower jaw that can lead to uneven teeth and grinding.