Orthodontic Vocabulary


A wire that is inserted in your brackets and attached with colored rubber bands or ties.

Ball Hook or Hook

A part of the bracket used for attachment of the rubber bands/elastics.


A metal ring that is attached to your back molars.


The attachment created by adhering a bracket or band to your teeth.


A small ceramic or stainless steel brace that is attached to your teeth to hold your archwire in place.

Elastic (Rubber Band)

A small rubber band that is attached to multiple brackets to move your teeth into correct position.

Elastic Tie

A small rubber band that is stretched around your bracket to secure the archwire to the bracket. These come in many colors, and are changed at each appointment.


Orthodontic headgear is a type of orthodontic appliance that attaches to braces or expanders to help correct severe bite problems. A variation includes reverse pull headgear, or a facemask.

Lip Bumper

A molded piece of plastic attached to your archwire. It is used to hold back the molars on your lower jaw to provide more space for your other teeth.


This word literally means “bad bite.” Malocclusion is a problem with the way the upper and lower teeth fit together when you bite or chew.

Class I Malocclusion

Your upper and lower teeth line up correctly, but your teeth are crooked, crowded or turned.

Class II Malocclusion

Your upper teeth protrude from your lower teeth. This is also called an overjet.

Class III Malocclusion

Your lower teeth protrude in front of your upper teeth. This is also called an underbite.


The amount the upper front teeth overlap the lower front teeth.

Rapid Palatal Expander

An orthodontic appliance that is attached to your upper molars. This appliance expands the upper arch by using gradual gentle force.


A retainer can be a removable or bonded appliance. A removable retainer is worn at night, typically on your upper arch, to hold your teeth in position after braces are removed. A bonded retainer is a wire that is bonded or glued, typically behind your lower front six teeth, to hold teeth in the correct position.

Separators or spacers

Small rubber bands that are inserted between molars to slightly move them apart so that bands may be placed


A shortened name for an elastic tie (see above).

Twin Block Appliance

A removable appliance consisting of two plates for the upper and lower teeth. When worn, the Twin Block postures the lower jaw forward and opens the bite between the upper and lower jaws