Visual glossary of orthodontic terms

When you go for an orthodontic consultation,you may hear unfamiliar terms related to diagnosis and treatment process. Although the orthodontist should explain all incomprehensible wordsto the patient, it is better for the patient to find information about the orthodontic treatment before orthodontics. For this reason,we have prepared a list of frequently used terms that you may hear from your orthodontist during the consultation and even during the orthodontic treatment.


Archwire is a special U-shaped metal alloy designed to help straighten and move the teeth in a custom way. It attaches to orthodontic brackets to conduct tooth movement.

Orthodontic band

An orthodontic band is a type of bracket used for orthodontics of molar teeth. This band is wrapped around the posterior teeth.

Orthodontic bonding

It is a process in which brackets are attached to teeth by orthodontic adhesive.

Orthodontic bracket

A small piece of metal or ceramic that is glued to each tooth. The orthodontic bracket acts as an “anchor” allowing to control the movement of each tooth individually. Orthodontic wire passes through the brackets.


Grinding of teeth, typically during sleep and unconsciously is called bruxism.


A crossbite is a malocclusion (bite problem) where the top teeth and bottom teeth do not come together when the mouth is closed or do not bite in the correct position.

Dental crowding

Tooth misalignment because of insufficient space in the maxillary arch. In this condition, because the jaw is small or the teeth are larger, due to the lack of enough space for growth, the teeth become crowded.


Removal of orthodontic brackets bonded or attached to the front or back of the teeth. Debonding is the last step of orthodontic procedures using fixed braces.

Deep bite

A deep bite is a malocclusion or misalignment of the teeth in which the top front teeth overlap over the bottom teeth. It may also be called an overbite or a closed bite. Deep bites are often caused by a lower jaw that is shorter than the top jaw, causing a serious overlap.

Other orthodontic terms related to this phenomenon are micrognathia andmandibular prognathism.


Thedistance of more than half a millimeter between two adjacent teeth is called diastema.

Early orthodontic treatment

This treatment is also known as preventive orthodontics. Early orthodontic treatment is performed when the baby teeth have not completely come out and the permanent teeth have not fully come in. This treatment is the first stage of two-phase orthodontics.

Orthodontic elastics

Orthodontic elastics or rubber bands are usually attached to hooks on brackets or orthodontic archwires to help move teeth in specific directions.

Tooth extraction

Tooth extraction for orthodontics is one of the most important parts of orthodontic procedure. In some cases, it may be necessary to extract impacted wisdom tooth or other teeth to prepare sufficient space for the teeth movement.


Facemask is a device used to help the upper teeth or jaw move frontward. It is often used in the case of anterior crossbite.

Fixed appliances

Appliances that are used to correct dental irregularities but are attached to the teeth from the beginning to the end of the treatment are called fixed appliances. These devices are only adjusted by an orthodontist.


The frenum is a natural tissuebetween the upper lip and gum. You can see itin the mirror by raising your upper lip. Sometimes this band is too large that it creates a gap between the two front teeth in the maxilla. The removal surgery of this extra part is called frenectomy.

Functional appliances

Fixed or removable orthodontic appliances which use the patient’s muscular function to make tooth or jaw moveare called functional orthodontics. This method is often used to correct mandibular growth.

Habit therapy

A treatment designed to prevent potentially harmful habits (usually involving thumb or toe sucking or sticking tongue out). This treatment may also correct the irregularity of the teeth caused by such habits.

Hawley retainer

Hawley is a removable orthodontic retainer that is used to stabilize teeth in new positions after orthodontic treatment. This retainer consists of acrylic plastic and metal. It can also move the teeth slightly.

Orthodontic headgear

An orthodontic headgear is a device attaching to the braces and neck or back of the head to move the upper teeth or upper jaw backward or to prevent them from moving forward.

Herbst appliance

Herbst is an important orthodontic device (fixed or removable) that is attached to the first permanent molars in all four corners of the patient’s mouth to strengthen the growth of jawbone. This orthodontic appliance is very practical in fixed functional orthodontics.

Impacted tooth

If a tooth does not come in, or emerges partially, it is considered to be impacted. This mostly happens with the wisdom teeth (the third set of molars). An impacted tooth remains stuck in gum tissue or bone for various reasons. The area may be overcrowded, leaving no room for the teeth to emerge.


Dental impressions are negative imprints of the teeth and oral cavity (gums, surrounding tissues, etc.). Impression is used to diagnose orthodontic problems and to make special and custom devices.

Interceptive orthodontic treatment

Orthodontic treatment while the patient still has primary or baby teeth. This treatment starts before the permanent teeth come out. This treatment is also called early orthodontic treatment or phase 1orthodontic treatment.

Lateral cephalometric radiograph

X-ray of the lateral part of the face and skull to measure the relationship of the teeth to the jaws and the jaws to the skull. This radiography is used to diagnose orthodontic problems.

Leeway space

Leeway space is the size differential between the primary posterior teeth (canine, first and second molars) and their permanent successors. This space can be used to reduce the crowd of the anterior teeth.

Lingual holding arch

It is a fixed orthodontic appliance that contains a wire running along the back of the lower teeth and attaches to the lower molar teeth. Used to preserve space during tooth transition (from baby teeth to permanent teeth).


Jaw deflection or abnormal placement of the upper and lower jaws and teeth while closing the mouth is called malocclusion.

Mixed dentition

A developmental stage in which baby and permanent teeth are present in the mouth at the same time. This period is from about 6 years old to 12 years old.


A plastic removable appliance which covers the teeth. Mouthguard is used during contact sports in order to protect the teeth and jaw structures.


O-ring is a round elastic fastening the orthodontic wire passing through the slit of the bracket. O-rings can be transparent or colored.

Open bite

A type of malocclusion and malformation of the jaw in which the front teeth of the maxilla and the front teeth of the mandible do not meet when the mouth is closed. In other words, there is a significant distance between the upper and lower teeth in the anterior part when the mouth is closed.


An orthodontist is a specialist dentist who has received theoretical and practical training about the relationship between the jaw, face, and teeth for at least 2 years after the general dental course at the school of dentistry. An orthodontist specializes in the movement of teeth as well as the improvement of dental and facial structures.

Orthognathic surgery

Orthognathic surgery or jaw surgery is a type of surgery for orthodontics performed by an oral surgeon. This surgery is usually done in conjunction with orthodontic treatment.


An overbite, also referred to as a “deep bite” is when the top teeth protrude out farther than the lower teeth. This is often referred to as having “buck teeth”. Just like underbite, this can be caused by genetics, prolonged pacifier and bottle use beyond infant years, and thumb sucking.


An overjet is when the upper teeth protrude outward and sit over the bottom teeth. Having an overjet doesn’t only affect your appearance, you may have also difficulty chewing, drinking, and biting, or jaw pain.

Panoramic radiograph

Radiography of lower and upper jaws, teeth, and surrounding structures in order to diagnose orthodontic problem.

Rapid palatal expansion

It is a method in which the width and size of the upper or lower jaw is increased by using a fixed device called palatal expander. It is used to correct posterior crossbite and can be bandaged or attached to a tooth.

Removable Appliances

Orthodontic tools that are not permanently attached to the teeth and can be removed from the mouth are called removable appliances. Retainers andaligners are in the category of removable appliances.


Retainer is a device for the post-orthodontic period used after treatment to maintain the position of the straightened teeth. It can be fixed or removable.


Tiny elastics which are placed between back teeth and create gaps to embedinterdental strips.

Space maintainer

A device that is applied when baby teeth come out prematurely to prevent the space from occupation before the permanent teeth come in. Orthodontic spacemaintaineractually are used to maintain free space.

Temporomandibular joint (TMJ)

One of the two joints paired between the mandible and the skull. It is located right in front of the ear.


An underbite is characterized by the lower jaw protruding beyond the upper jaw.