Scissor bite is a type of bite seen in some mammals such as dogs and humans. This type of bite involves outward positioning of the upper posterior teeth and inward positioning of the lower posterior teeth. The reason for this happening is an expanded upper arch and constricted lower arch. [1] [2]
In humans, a scissor bite does not have any significant influence on the facial profile. However, the chewing habits is influenced due to no contact of molars. Treatment of scissor bite may involve expansion device of the lower arch, usage of cross-elastics in an orthodontic treatment. [3] A new method of using Temporary Anchorage Devices (TADs) has been shown to correct the scissor bite in humans. [4]
Orthodontics is a dentistry specialty that addresses the diagnosis, prevention, management, and correction of mal-positioned teeth and jaws, and misaligned bite patterns. It may also address the modification of facial growth, known as dentofacial orthopedics.
Dental braces are devices used in orthodontics that align and straighten teeth and help position them with regard to a person's bite, while also aiming to improve dental health. They are often used to correct underbites, as well as malocclusions, overbites, open bites, gaps, deep bites, cross bites, crooked teeth, and various other flaws of the teeth and jaw. Braces can be either cosmetic or structural. Dental braces are often used in conjunction with other orthodontic appliances to help widen the palate or jaws and to otherwise assist in shaping the teeth and jaws.
In orthodontics, a malocclusion is a misalignment or incorrect relation between the teeth of the upper and lower dental arches when they approach each other as the jaws close. The English-language term dates from 1864; Edward Angle (1855-1930), the "father of modern orthodontics", popularised it. The word "malocclusion" derives from occlusion, and refers to the manner in which opposing teeth meet.
A palatal expander is a device in the field of orthodontics which is used to widen the upper jaw (maxilla) so that the bottom and upper teeth will fit together better. This is a common orthodontic procedure. Although the use of an expander is most common in children and adolescents 8–18 years of age, it can also be used in adults, although expansion is slightly more uncomfortable and takes longer. A patient who would rather not wait several months for the end result by a palatal expander may be able to opt for a surgical separation of the maxilla. Use of a palatal expander is most often followed by braces to then straighten the teeth.
Orthodontic technology is a specialty of dental technology that is concerned with the design and fabrication of dental appliances for the treatment of malocclusions, which may be a result of tooth irregularity, disproportionate jaw relationships, or both.
Occlusion, in a dental context, means simply the contact between teeth. More technically, it is the relationship between the maxillary (upper) and mandibular (lower) teeth when they approach each other, as occurs during chewing or at rest.
Overjet is the extent of horizontal (anterior-posterior) overlap of the maxillary central incisors over the mandibular central incisors. In class II malocclusion the overjet is increased as the maxillary central incisors are protruded.
Crossbite is a form of malocclusion where a tooth has a more buccal or lingual position than its corresponding antagonist tooth in the upper or lower dental arch. In other words, crossbite is a lateral misalignment of the dental arches.
A lingual arch is an orthodontic device which connects two molars in the upper or lower dental arch. The lower lingual arch (LLA) has an archwire adapted to the lingual side of the lower teeth. In the upper arch the archwire is usually connecting the two molars passing through the palatal vault, and is commonly referred as "Transpalatal Arch" (TPA). The TPA was originally described by Robert Goshgarian in 1972. TPAs could possibly be used for maintaining transverse arch widths, anchorage in extraction case, prevent buccal tipping of molars during Burstonian segmented arch mechanics, transverse anchorage and space maintenance.
Cephalometric analysis is the clinical application of cephalometry. It is analysis of the dental and skeletal relationships of a human skull. It is frequently used by dentists, orthodontists, and oral and maxillofacial surgeons as a treatment planning tool. Two of the more popular methods of analysis used in orthodontology are the Steiner analysis and the Downs analysis. There are other methods as well which are listed below.
Interproximal reduction (IPR) is the practice of mechanically removing enamel from between the teeth to achieve orthodontic ends, such as to correct crowding, or reshape the contact area between neighboring teeth. After reducing the enamel, the procedure should also involve anatomic re-contouring and the protection of interproximal enamel surfaces.
Lingual braces are one of the many types of the fixed orthodontic treatment appliances available to patients needing orthodontics. They involve attaching the orthodontic brackets on the inner sides of the teeth. The main advantage of lingual braces is their near invisibility compared to the standard braces, which are attached on the buccal (cheek) sides of the tooth. Lingual braces were invented by Craven Kurz in 1976.
Anchorage in orthodontics is defined as a way of resisting movement of a tooth or number of teeth by using different techniques. Anchorage is an important consideration in the field of orthodontics as this is a concept that is used frequently when correcting malocclusions. Unplanned or unwanted tooth movement can have dire consequences in a treatment plan, and therefore using anchorage stop a certain tooth movement becomes important. Anchorage can be used from many different sources such as teeth, bone, implants or extra-orally.
A lip bumper is a dental appliance used in orthodontics, for various purposes to correct a dentition by preventing the pressure from the soft tissue. Lip bumpers are usually used in orthodontic treatment where the patient has a crowded maxillary or mandibular teeth in an arch.
Elastics are rubber bands frequently used in the field of orthodontics to correct different types of malocclusions. The elastic wear is prescribed by an orthodontist or a dentist in an orthodontic treatment. The longevity of the elastic wear may vary from two weeks to several months. The elastic wear can be worn from 12 to 23 hours a day, either during the night or throughout the day depending on the requirements for each malocclusion. The many different types of elastics may produce different forces on teeth. Therefore, using elastics with specific forces is critical in achieving a good orthodontic occlusion.
Activator Appliance is an Orthodontics appliance that was developed by Viggo Andresen in 1908. This was one of the first functional appliances that was developed to correct functional jaw in the early 1900s. Activator appliance became the universal appliance that was used widely throughout Europe in the earlier part of the 20th century.
Pendulum is an orthodontic appliance, developed by James J. Hilgers in 1992, that use forces to distalize the upper 1st molars to create space for eruption of impacted teeth or allowing correction of Class 2 malocclusion. This appliance is a fixed type of distalizing appliance that does not depend on the compliance of each patient to work. Hilgers published an article in Journal of Clinical Orthodontics in 1992 describing the appliance.
Intrusion is a movement in the field of orthodontics where a tooth is moved partially into the bone. Intrusion is done in orthodontics to correct an anterior deep bite or in some cases intrusion of the over-erupted posterior teeth with no opposing tooth. Intrusion can be done in many ways and consists of many different types. Intrusion, in orthodontic history, was initially defined as problematic in early 1900s and was known to cause periodontal effects such as root resorption and recession. However, in mid 1950s successful intrusion with light continuous forces was demonstrated. Charles J. Burstone defined intrusion to be "the apical movement of the geometric center of the root (centroid) in respect to the occlusal plane or plane based on the long axis of tooth".
Open bite is a type of orthodontic malocclusion which has been estimated to occur in 0.6% of the people in the United States. This type of malocclusion has no vertical overlap or contact between the anterior incisors. The term "open bite" was coined by Carevelli in 1842 2 as a distinct classification of malocclusion. Different authors have described the open bite in a variety of ways. Some authors have suggested that open bite often arises when overbite is less than the usual amount. Additionally, others have contended that open bite is identified by end-on incisal relationships. Lastly, some researchers have stated that a lack of incisal contact must be present to diagnose an open bite.
Orthodontic indices are one of the tools that are available for orthodontists to grade and assess malocclusion. Orthodontic indices can be useful for an epidemiologist to analyse prevalence and severity of malocclusion in any population.