Orthodontics

Crossbite —The condition in which the upper teeth bite inside the lower teeth.

Crown —The natural part of the tooth covered by enamel. A restorative crown is a protective shell that fits over a tooth.

Deep bite —A closed bite; a deep or excessive overbite in which the lower incisors bite too closely to or into the gum tissue or palate behind the upper teeth.

Eruption —The process of a tooth breaking through the gum tissue to grow into place in the mouth.

Impacted tooth —Any tooth that is prevented from reaching its normal position in the mouth by another tooth, bone, or soft tissue.

Incisors —The eight front teeth.

Interceptive orthodontics —Preventative orthodontics; early, simpler orthodontic treatment.

Malocclusion —The misalignment of opposing teeth in the upper and lower jaws.

Molars —The teeth behind the primary canines or the permanent premolars, with large crowns and broad chewing surfaces for grinding food.

Open bite —A malocclusion in which some teeth do not meet the opposing teeth.

Orthognatic surgery —Surgery to alter the relationships of the teeth and/or supporting bones, usually in conjunction with orthodontic treatment.

Overbite —Protrusion of the upper teeth over the lower teeth.

Plaque —A sticky film of saliva, food particles, and bacteria that attaches to the tooth surface and causes decay.

Retainer —An orthodontic appliance that is worn to stabilize teeth in a new position.



Source:
http://www.encyclopedia.com/topic/orthodontics.aspx