Orthodontics "orthodontia" or the specialty of dentistry that is concerned with the study and treatment of malocclusions, which may be a result of tooth irregularity, disproportionate jaw relationships, or both.
Orthodontic treatment can be carried out for purely aesthetic reasons - improving the general appearance of patients' teeth for cosmetic reasons- but treatment is often prescribed for practical reasons, providing the patient with a functionally improved bite (occlusion).
Treatment includes fixed appliances, most commonly dental braces, which can be made from stainless steel or a more esthetic ceramic material; removable appliances, or "plates"; headgear; elastic bands; and other appliances, including expansion appliances, and functional appliances.
After a course of active orthodontic treatment, patients will often wear retainers, which will maintain the teeth in their improved position whilst the surrounding bone reforms around them. The retainers are generally worn full-time for a short period, perhaps 6 months to a year, and then worn periodically (typically nightly during sleep) for as long as the orthodontist recommends. It is possible for the teeth to stay aligned without regular retainer wear. However, there are many reasons teeth will crowd as a person ages and thus, there is no guarantee that teeth, orthodontically treated or otherwise, will stay aligned without retention. For this reason, many orthodontists recommend periodic retainer wear for many years (or indefinitely) after orthodontic treatment.
An orthodontist is a dentist who specializes in diagnosing and treating malocclusions, which are mis-alignments of the teeth, jaws, or both. Following dental school, an orthodontist completes 2-3 years of full-time additional training resulting in a specialty certificate in orthodontics. In many orthodontic training programs, students can also earn one of three master's degree (Master of Science - MS; Master of Dental Science - MDS, or Master of Science in Dentistry - MSD) in addition to a specialty certificate.
The orthodontist will align teeth with respect to the surrounding soft tissues, with or without movement of the underlying bones (which can be moved either through orthopaedic or orthognathic movements). Orthopaedic movements are attained through the judicious use of (mainly) acrylic appliances (functional appliances), that influence the position of the jaws relative to one other and the face, and will be carried out on growing children. The correct application of orthopaedic appliances can influence the development of an adolescent's jawline, giving a much improved aesthetic and functional result.
Orthognathic movement is achieved by surgically repositioning the jaw(s), in patients that have completed their growth. Such surgical treatment is carried out by maxillofacial surgeons who work closely with the orthodontic team.
One of the most common situations leading to orthodontic treatment is crowding of the teeth. In this situation, there is insufficient room for the normal complement of adult teeth, which can sometimes result in teeth being extracted. Crowding of teeth is recognised as an affliction that stems in part from a modern western lifestyle. We do not know for sure whether it is due to the consistency of western diets; a result of mouthbreathing; or the result of an early loss of deciduous (milk, baby) teeth due to decay. It is also possible that Homo sapiens have evolved smaller jaws without a reduction in the number of teeth they will house happening at the same time. orthodontistry is not always for aesthetic purposes. Braces may be fitted in the case of an overbite to help prevent the occurrence of teeth being knocked out in an accident, for example, hockey or skating.
Much has been made in the media of links between tooth extraction and temporo-mandibular joint dysfunction (problems, including clicking and jamming, of the jaw joint). No research has shown a definitive link between extraction of teeth and jaw joint problems. Most temporo-mandibular joint problems are a result of the patient having a clenching habit - that is the patient bites the teeth together on a regular basis (e.g. when under stress).