Elastics (orthodontics)

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Elastics are rubber bands frequently used in the field of orthodontics [1] 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. [2]

Contents

The term intermaxillary elastics is used when elastics can go from the maxillary to the mandibular arch. Intra-maxillary elastics are elastics used in one arch only, either mandibular or maxillary. People using elastics for orthodontic correction change their elastics three to four times during the day. Elastic wear is recommend to be used in a rectangular wire to minimize side effects. Elastic wear depends on the compliance of the patient. A non-compliant patient should never be instructed to continue wearing elastics, for whom other options may be considered. [3]

History

Natural rubber, used by the Incan and Mayan cultures, was the first known elastomer. Charles Goodyear developed the process of vulcanization, [4] after which the use of natural rubber increased. Henry Albert Baker is the first person known to have used elastics to correct the position of teeth. In the late 1800s he named his elastic wear the Baker Anchorage. Others, including Edward Angle, the father of orthodontics, suggest that Calvin Case was the first to use intermaxillary elastics.

Natural rubber is known to absorb water, and its elasticity deteriorates fairly quickly. Therefore, latex elastics became prominent in orthodontic usage in the early 1900s. Later synthetic elastics developed in the 1960s superseded other types of elastics for use in orthodontic correction.

Elastic forces

Elastics are available in many different type of forces. Following is the list of forces that can be found in different elastics. The forces and the labelling of the forces may depend on different manufacturers and types of elastics used. These forces pertain to intermaxillary elastics.

Force RatingForce (oz.)Force (g)
Light2 oz.56.7 g
Medium-Light3 1/2 oz.99.2 g
Medium4 oz.113.4 g
Medium-Heavy5 1/2 oz.155.9 g
Heavy6 oz.170.1 g
Extra Heavy8 oz.226.8 g

Class II elastics

Class 2 elastics are used from the lower first molar to the upper canine tooth. [1] They can be used for many different reasons, such as Class 2 malocclusions, to reinforce anchorage in a case where an extraction has been done, to allow the maxillary incisors to move backwards, and to correct midline deviation and allow buccal movement of backward-tipped lower incisors. Orthodontists generally use 12-16 oz elastics (3/16") in extraction cases or 2× 6 oz elastics on either side of the mouth (3/16"), but in non extraction cases 16-20 oz elastics (3/16") or 2× 8 oz elastics are used. It is very important to know the side effects of Class II elastics before using them in an orthodontic treatment. The following are the effects of Class 2 elastics: [5] [6]

Effect on Class II Malocclusion

A systematic review done by Janson et al. [7] looking at the effect of Class 2 elastics in correcting class II malocclusions concluded that Class II elastics are effective in correcting Class II malocclusions and that their effects are primarily dento-alveolar.

Class III elastics

Class 3 elastics are used when the molar relationship is close to Class 1 malocclusion. Class 3 malocclusions due to skeletal discrepancy (mandibular prognathism) cannot be corrected with Class 3 elastics. [8] It is important to evaluate soft tissue and hard tissue esthetics of a patient before attempting to use Class 3 elastics. Elastic wear will only produce changes in dentition, with no documented changes produced in soft and hard tissue. The following are the side-effects of Class 3 elastics: [9]

Elastic ligatures

The small elastic band used to affix the archwire to the bracket is called a ligature. Usually changed at each adjustment, these come in many varied colours, including transparent. A series of ligatures connected to each other and used to pull teeth together with more strength is called a power chain. Ligatures can also be made of wire. Self-ligation makes use of a bracket with a sliding or rotating mechanism to ligate an archwire. This type of bracket replaces traditional elastic ligatures and typically cuts orthodontic appointment times drastically [ citation needed ]. Currently, self-ligating brackets make up about 10 percent of total bracket sales worldwide.

See also

Related Research Articles

<span class="mw-page-title-main">Orthodontics</span> Correctional branch of dentistry

Orthodontics is a dentistry specialty that addresses the diagnosis, prevention, management, and correction of mal-positioned teeth and jaws, as well as misaligned bite patterns. It may also address the modification of facial growth, known as dentofacial orthopedics.

<span class="mw-page-title-main">Dental braces</span> Form of orthodontics

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.

Hypodontia is defined as the developmental absence of one or more teeth excluding the third molars. It is one of the most common dental anomalies, and can have a negative impact on function, and also appearance. It rarely occurs in primary teeth and the most commonly affected are the adult second premolars and the upper lateral incisors. It usually occurs as part of a syndrome that involves other abnormalities and requires multidisciplinary treatment.

<span class="mw-page-title-main">Malocclusion</span> Medical condition

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.

<span class="mw-page-title-main">Palatal expansion</span> Orthodontics device to widen the upper jaw

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. 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 more uncomfortable and takes longer in adults. A patient who would rather not wait several months for the end result achieved 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.

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<span class="mw-page-title-main">Crossbite</span> Medical condition

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The Damon system of orthodontics is one of many fixed, passive, self-ligating methods of correcting malocclusions. Passive self-ligating systems use brackets that do not require elastic o-rings to hold the wires in place. By not using the elastic o-rings, it is said that the wires freely slide through the slots without friction. However, this may not be correct as it allows more rotation or tipping of teeth before the bracket edges contact the wire, resulting in friction. It is believed that not using o-rings results in better oral hygiene but the research is equivocal, with findings both for and against the theory. To hold the wires in place, the Damon System uses small sliding doors. The addition of 'stops' on the wires helps prevent the wire from becoming displaced from its intended location.

<span class="mw-page-title-main">Lingual arch</span>

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.

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<span class="mw-page-title-main">Anchorage (orthodontics)</span> Way of resisting tooth movement in orthodontics

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Frankel appliance or Frankel Functional Regulator is an orthodontic functional appliance which was developed by Rolf Fränkel in 1950s for treatment to patients of all ages. This appliance primarily focused on the modulation of neuromuscular activity in order to produce changes in jaw and teeth. The appliance was opposite to the Bionator appliance and Activator appliance.

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 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.

References

  1. 1 2 "Elastics For Braces: Rubber Bands in Orthodontics". Orthodontics Australia. December 15, 2019. Retrieved December 13, 2020.
  2. Nolting, Paul R. (August 1, 1937). "Intermaxillary elastics". International Journal of Orthodontia and Oral Surgery. 23 (8): 812–813. doi:10.1016/S1072-3498(37)80050-3.
  3. Stewart, C. M.; Chaconas, S. J.; Caputo, A. A. (April 1, 1978). "Effects of intermaxillary elastic traction on orthodontic tooth movement". Journal of Oral Rehabilitation. 5 (2): 159–166. doi:10.1111/j.1365-2842.1978.tb01209.x. ISSN   0305-182X. PMID   280630.
  4. "Charles Goodyear | Goodyear Corporate". corporate.goodyear.com. Retrieved September 3, 2016.
  5. "Timișoara Medical Journal -The Effect of Intermaxillary Elastics in Orthodontic Therapy". www.tmj.ro. Retrieved September 3, 2016.
  6. Janson, Guilherme; Sathler, Renata; Fernandes, Thais Maria Freire; Branco, Nuria Cabral Castello; Freitas, Marcos Roberto de (March 1, 2013). "Correction of Class II malocclusion with Class II elastics: a systematic review". American Journal of Orthodontics and Dentofacial Orthopedics. 143 (3): 383–392. doi:10.1016/j.ajodo.2012.10.015. ISSN   1097-6752. PMID   23452973. S2CID   205354830.
  7. Janson, Guilherme; Sathler, Renata; Fernandes, Thais Maria Freire; Branco, Nuria Cabral Castello; de Freitas, Marcos Roberto (March 1, 2013). "Correction of Class II malocclusion with Class II elastics: A 2013 systematic review of 11 studies". American Journal of Orthodontics and Dentofacial Orthopedics. 143 (3): 383–392. doi:10.1016/j.ajodo.2012.10.015. PMID   23452973. S2CID   205354830.
  8. Janson, Guilherme; de Freitas, Marcos Roberto; Araki, Janine; Franco, Eduardo Jacomino; Barros, Sérgio Estelita Cavalcante (August 1, 2010). "Class III subdivision malocclusion corrected with asymmetric intermaxillary elastics". American Journal of Orthodontics and Dentofacial Orthopedics. 138 (2): 221–230. doi:10.1016/j.ajodo.2008.08.036. ISSN   1097-6752. PMID   20691365.
  9. Zimmer, Bernd; Nischwitz, Diana (September 1, 2012). "Therapeutic changes in the occlusal plane inclination using intermaxillary elastics". Journal of Orofacial Orthopedics. 73 (5): 377–386. doi:10.1007/s00056-012-0100-5. ISSN   1615-6714. PMID   22955576. S2CID   27746651.