How to turn an expander

1) Activation of an expander is usually done by a parent, guardian, or someone other than the patient. On the day the expander is placed, we give you a key that inserts into an opening in the centre of the appliance.

2) It is easiest to have the patient lie down on a bed or couch where there is good light. Then, the patient tilts their head back so that the expander can be seen clearly. There are arrows on the middle metal portion of the expander pointing in the direction that the turn should be made.

3) The key is inserted into the hole visible until it is firmly in place. Remember that the bend in the key will not let you insert too far.

4) Follow the arrows facing towards the back of the mouth to apply a small amount of pressure to swivel the key in that direction. As you turn, the fender rotates and a new hole becomes visible. The rotation stops when the key meets the back of the expander.

5) When the turn is complete, simply push down toward the tongue while you continue to lightly apply pressure toward the back of the mouth to remove the key. You should then see the next hole for insertion at the top. You will be given specific instructions as to how many turns to complete before the next appointment.

Additional Information

What is a rapid palatal expander?

A rapid palatal expander (RPE) is an appliance used to widen the two halves of the top jaw, also known as the palate or maxilla. The two halves are joined together by a “suture” in the centre of the roof of the mouth. The RPE is attached to the upper back teeth and eases the suture apart, which makes the jaw wider. As the jaw expands, new bone fills in between the two halves of the palate. This appliance can be used to fix a cross bite and create more space for the teeth.

How does it work?

An expander is usually placed no earlier then age 7 and no later than age 14-15. This is because the upper jaw is still malleable at this age to adapts to orthopaedic pressure. With each turn of the screw, the appliance widens 1/5th of a millimeter. When it is turned every day for a month, you have achieved 6 mm of upper jaw expansion. This appliance creates enough pressure to widen the upper jaw but is slow enough that the tissues can adapt to the changes without great discomfort to the patient.

What problems can you have with an expander?

The two most common problems that can arise when having an RPE is that food can become trapped between the expander and the roof of the mouth or difficulty making the activation turn. When the expander is placed, we show you how to clean around it. Please remember to swish or gargle with warm salt water to help flush out the food. The other problem that can arise is not making a complete turn. Sometimes, you think you made the complete turn and then remove the key. It appears as if the turn was completed successfully, but when you go to make another turn the key will not go into the new hole. You will then have to return to the previous hole which is located towards the back of the mouth, insert key and complete the turn

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