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Common Appliances

Below is a list of appliances commonly used at AvA Orthodontics. For each appliance there is a brief summary of why Dr. Amin Movahhedian and Dr. Hamed Vaziri use them. If you are wearing any of these appliances and simply want to know how to take care of it at home, please check our other page: Instructions

Nance

It consists of the following parts 
  1. Bands around the first permanent molars on each side
  2. A thin acrylic button that rests on the palate of the mouth
  3. Two arms connecting the parts

It is used for the following reasons:

  1. Space Maintainer: To prevent the back teeth from coming forward after a premature loss of the baby teeth. If we don’t have a nance in place, the permanent molars will come forward and close the space that needs to be available for the eruption of the permanent premolars.
     
  2. Anchorage: To correct the position of the teeth sticking out, an orthodontist will decide to pull two teeth and utilize the space gained to push the front teeth back. However most of the time we don’t want the back teeth to come forward at all. In order to hold the back teeth from moving, to allow us to retract the front teeth as much as possible, the nance is used.
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Lingual Arch

It consists of the following parts
  1. Bands around the first permanent molars on each side
  2. An arm connecting the bands 
It is used as a space maintainer for the lower teeth. If baby teeth are lost and the permanent teeth that are replacing them won’t erupt soon, there is a high chance that the back teeth will move forward and occupy the empty space partially or fully. This could cause impaction of the permanent teeth or crowding. In order to reserve the space for the future permanent teeth and hold the back teeth where they are, a Lingual Arch will be necessary.
 
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Palatal Expander

The common names for it: Rapid palatal expander or RPE, Maxillary expander.
It is a butterfly looking appliance that consists of the following parts
  1. A keyhole
  2. Bands on the first molars
  3. Two arms adjacent to the palatal surface of the teeth on each side
  4. Connectors that hold the pieces together
  5. A key for activation
It is used to widen the upper dental arch when the palate is constricted. Each turn of the key increases the width of the appliance 0.2mm. Because we can modify the bone on young and growing patients, it will have the most effective orthopedic result. While the upper jaw widens, some space may develop between the front teeth. Usually for each millimeter increase in the back, we expect .3mm space in the front which shows itself as space between the two front teeth. The space usually closes by itself or we close it with braces. After the expansion is complete, we keep the expander in place for a few more months to make sure what we have achieved is stable. Sometimes there may be some level of discomfort after each turn, however the feeling of pain is quite uncommon. 
 
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Schwartz Expander

It is either removable or fixed.
  • The fixed expander looks like a lingual arch with the keyhole right in the middle.
  • The removable appliance looks like a lower Hawley retainer with the keyhole right in the middle.
 
It is used to widen the lower dental arch. Expansion allows us to make more room for the remaining permanent teeth that haven’t erupted or for correcting the crossbite. Unlike the maxillary expander, there will not be any orthopedic expansion. 
 
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TPA

It consists of the following parts 
  1. Bands around the first permanent molars on each side
  2. Two arms connecting the parts

It is used for the following reasons

  1. Space Maintainer: To prevent the back teeth from coming forward after a premature loss of the baby teeth. If we don’t have a TPA in place, permanent molars will come forward and close the space that needs to be available for the eruption of the permanent premolars.
     
  2. Anchorage for impacted canine: Sometimes to bring in impacted canines in the mouth, we need additional force from the molars. In order to minimize side effects on the molars while doing that we need to hold the molars stationary in their position.  Therefore, a TPA is a great appliance used to achieve this goal.
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Forsus

Forsus are used when the upper teeth are sticking out in comparison to the lower teeth. This means there is an extended overjet, you may know it as “overbite”. To be able to fix the “overbite”, an orthodontist needs to push the upper teeth backward and the lower teeth forward. It is possible by a few appliances. The most well-known appliance is Headgear. Dr. Amin Movahhedian and Dr. Hamed Vaziri are not big fans of headgear because it is an extra-oral appliance and patients do not like to wear it. 
 

Advantages of Forsus

  • All of its parts are inside the mouth.  
  • It doesn’t restrict jaw movements. 
  • It doesn’t interfere with eating, chewing, speaking, etc. 
  • It is fixed in place means you cannot take it out.  
It consists of the following parts
  1. A metal rod with a connector on each end
  2. A coil spring around the rod
  3. Bands on the upper molars
The coil spring along the metal core is clipped to the band around the upper first molar and crimped around the lower wire between the canine and the first bicuspid. The pressure of the spring creates constant and mild pressure which results in moving the upper teeth backward and the lower teeth forward. 

In the following video you will the see comparison of headgear versus Forsus

 
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Tongue crib

It is a habit breaker appliance for tongue thrusters. With the help of this appliance we train the tongue not to come between front teeth during swallowing, speaking etc. 
 
At AvA Orthodontics we use two different designs for this appliance.
  • Lingual arch design: It is placed on the lower teeth. It looks like a lingual arch with vertical bars welded to it in the front area.
  • Nance design: It is placed on the upper teeth. It looks like a Nance (with or without the acrylic button) with vertical bars welded to it in the front area. 
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3-way sagittal

It consists of the following parts
  1. Three keyholes
  2. Acrylic connector plate covering the palate
  3. A key for activation
 
It is used when there is a constricted upper arch along with an underbite. It is mainly a palatal expander with additional set of keys by which we can move the front teeth forward and correct the underbite. Like a palatal expander it works best in young and growing patients. After the expansion is complete, we keep the expander in its place for a few more months to make sure what we have achieved is stable. Sometimes there is some level of discomfort after each turn, however pain is quite uncommon.
 
We look forward to being a part of your wonderful, life-changing experience.

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