Orthodontic technology

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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.

Contents

There are three main types of orthodontic appliances: active, passive and functional. All these types can be fixed or removable.

Active appliances

An active appliance is a device used to apply forces to the teeth to change the relationship of the teeth.

Removable active appliances

Removable active appliances are intended for simple tipping movements. Use of removable appliances in modern orthodontics is much more limited than in the past due to their various shortcomings.

Fixed active appliances

Edward Angle, regarded as the father of American orthodontics, [2] developed many universal fixed active appliances, unifying orthodontic practice. [3]

Functional appliances

Upper and Lower Jaw Functional Expanders Upper and Lower Jaw Functional Expanders.jpg
Upper and Lower Jaw Functional Expanders

There is a totally different orthodontics approach without extraction and pain, is called functional orthodontics, the functional orthodontic technology is different and called functional appliance, that is an appliance that produces all or part of its effect by altering the position of the mandible/maxilla. Also known as dentofacial orthopaedic appliances, these appliances utilize the muscle action of the patient and responses of nervous system to produce orthodontic or orthopaedic forces. Various functional appliances have been described. There is a List of Orthodontic Functional Appliances.

Functional appliances are orthodontic appliances that are used to correct a malocclusion by avoiding mouth breathing and utilising, eliminating or guiding muscle function forces, tooth eruption and growth. Although there are many different types (fixed and removable), the majority work by via forward mandibular posturing to promote mandibular growth in growing patients. They are mostly used to reduce the projection of the front teeth (increased overjet) in patients with class II malocclusion. These appliances are not very effective at correcting dental irregularities or improving alignment and so are usually followed by treatment with fixed appliances. [4] Whilst functional appliances have been suggested for treatment of Class III malocclusion, their limited success has been superseded by substantially improved treatment results with protraction headgear.

Orthodontic headgear

Headgear Headgear - Vertical Pull.jpg
Headgear

Orthodontic headgear is a type of appliance attached to dental braces that aids in correcting more severe bite problems.

Headgear is an orthodontic appliance for the correction of Class II correction, typically used in growing patients to correct overbites by holding back the growth of the upper jaw, allowing the lower jaw to catch up.

The headgear can also be used to make more space for teeth to come in. The headgear is then attached to the molars (via molar headgear bands & tubes), and helps to push or draw them backwards in the mouth, opening up space for the front teeth to be moved back using braces and bands.

Full orthodontic headgear with headcap, fitting straps, facebow, and elastics Full orthodontic headgear with headcap and fitting straps.jpg
Full orthodontic headgear with headcap, fitting straps, facebow, and elastics

Headgear needs to be worn approximately 12 to 22 hours a day to be truly effective in correcting the overbite, and treatment is usually anywhere from 6 to 18 months in duration, depending on the severity of the overbite and how much a patient is growing. [5]

Orthodontic facemask and reverse-pull headgear

Facemask Headgear - Reverse Pull2.jpg
Facemask

Facemask or reverse-pull headgear is used to control the growth of the maxillary and mandibular bones during orthodontic treatment.

The appliance is used in growing patients to correct under bites (known as a Class III orthodontic problem) by pulling forward and assisting the growth of the upper jaw, allowing the upper jaw to catch up.

Facemasks or reverse-pull headgear needs to be worn approximately 12 to 22 hrs to be truly effective in correcting the under bite, usually anywhere from 6 to 18 months depending on the severity of the bite and how much a patient is growing. [5]

The appliance normally consists of a frame or a centre bars that are strapped to the patients head during a fitting appointment. The frame has a section which is positioned in front of the patients mouth, which allows for the attachment of elastic or rubber bands directly into the mouth area. These elastics are then hooked onto the child's braces (brackets and bands) or appliance fitted in his or her mouth.

This creates a forward 'pulling' force to pull the upper jaw forward.

Fixed functional appliances

1) Permanent effect, independent of patient compliance, as it is fixed. 2) Esthetics, as it is small and lingually located. 3) Eliminates the need for two separate treatment phases, as it is suitable for use in parallel with complete multibracket appliance in both arches. 4) Flexibility in treatment timing, as it can be used anytime during the mixed and permanent dentition. 5) No interference with occlusal development. 6) Wide and comfortable range of mastication movements, as the appliance consists of two separate parts with no permanent and physical intermaxillary connection.

Treatment Timing

Timing of treatment with functional appliances is crucial as they must be used whilst the patient is still growing in order to achieve maximum benefit. It has been suggested that the best time to prescribe one of these appliances is in alignment with the pubertal grown spurt. [7]

Types

There are many different types of fixed and removable functional applications. Only a few of the most common are discussed below.

The most popular functional appliance is the Twin-block appliance as it has been found to be the most “patient-friendly”. [8] This consists of upper and lower removable appliances that each have bite blocks posturing the mandible into a forward position. [4] However, patient compliance can sometimes be an issue with this appliance as the bulky acrylic blocks can cause issues with eating and speaking and patients can easily remove them. [8] Removable Twin-blocks have been found to be as effective as the fixed Herbst appliance. [9]

The Herbst appliance is a fixed-functional appliance. It consists of sections attached to the upper and lower posterior teeth that are attached by a rigid arm pushing the mandible forwards. The fact that it is a fixed appliance eliminates the patient compliance issues that accompany the Twin-block appliance. [8] O’Brien et al. (2003) found that treatment the Herbst appliance displayed a lower failure-to-complete treatment rate (12.9%) than Twin-block appliances (33.6%). [10] However, the Herbst application still remains the less popular choice than the Twin-blocks due to a higher breakage rate and increased cost of appliance manufacture and clinical time. [4]

A myriad of other functional appliance have been invented including the standard activator, the medium opening activator (MOA), Bionator and Frankel. The MOA is a single piece functional appliance that allows for greater patient comfort with minimal acrylic than any of the other single-piece removable functional appliances but compliance with all of these can be limited due to these paradoxically limiting normal mandibular function during wear. All of these appliances allows selective eruption of the lower posterior teeth which is useful for reducing a deep overbite whilst correcting the Class II malocclusion. [4]

Additional benefits

Tulloch et al. (1998) found that functional appliances reduce the need for orthognathic surgery. [11] The use of functional appliances to correct Class II malocclusion can also have psychological benefits. O’Brien at el. (2003) found that early treatment using Twin-block appliances increased the patient's self-esteem and resulted in reduced negative social encounters. [9]

Digital Orthodontic Technology

There are 7 parts to an orthodontic assessment: case history, clinical examination, model analysis, functional analysis, cephalometric analysis, radiographic analysis of the teeth, and photographic analysis. [12] To focus specifically on radiographic and photographic analysis we can analyze the effect of digital technology in the field of orthodontics.

Radiography

Radiography has been used in dental offices for decades, but as digital technology expands there are various benefits to using digital radiography compared to conventional film. Digital radiography: decreases environmental burdens, improves accuracy in image processing, decreases time and increases efficiency, reduces radiation, and improves diagnosis and treatment planning for professionals. [13]

3D radiography is also becoming more prevalent in dental offices as well and provides numerous benefits for assessing and locating positions of various diagnosis such as TMJ problems, impacted teeth, and tooth eruptions. [14]

Digital Scanners

One of the most noticeable changes in digital dental technology is the adaptation of digital scanners in dental and specialty offices. A big change for patients specifically, is the transition from plaster model impressions to digital scanners. It provides more accurate impressions and is noticeably more comfortable for patients. [14] Digital scanners are also used as way for dental offices to manufacture aligners and retainers directly from their office. This allows for improved collaboration between offices through the ability to transfer scans electronically and it allows a direct removal of defects in the scan before being printed. [15]

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">Orthodontic headgear</span> Orthodontic device used to correct bite

Orthodontic headgear is a type of orthodontic appliance typically attached to the patient's head with a strap or number of straps around the patient's head or neck. From this, a force is transferred to the mouth/jaw(s) of the subject.

<span class="mw-page-title-main">Prognathism</span> Protrusion of the upper or lower human jaw

Prognathism, also called Habsburg chin, Habsburg's chin, Habsburg jaw or Habsburg's jaw primarily in the context of its prevalence amongst members of the House of Habsburg, is a positional relationship of the mandible or maxilla to the skeletal base where either of the jaws protrudes beyond a predetermined imaginary line in the coronal plane of the skull. In general dentistry, oral and maxillofacial surgery, and orthodontics, this is assessed clinically or radiographically (cephalometrics). The word prognathism derives from Greek πρό and γνάθος. One or more types of prognathism can result in the common condition of malocclusion, in which an individual's top teeth and lower teeth do not align properly.

<span class="mw-page-title-main">Orthognathic surgery</span> Surgery of the jaw

Orthognathic surgery, also known as corrective jaw surgery or simply jaw surgery, is surgery designed to correct conditions of the jaw and lower face related to structure, growth, airway issues including sleep apnea, TMJ disorders, malocclusion problems primarily arising from skeletal disharmonies, and other orthodontic dental bite problems that cannot be treated easily with braces, as well as the broad range of facial imbalances, disharmonies, asymmetries, and malproportions where correction may be considered to improve facial aesthetics and self-esteem.

<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">Overjet</span> Medical condition

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.

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

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.

Pre-eruption guidance is an orthodontic treatment method that allows for expansion of existing erupting teeth long before they appear in the mouth. The use off pre-eruption guidance appliances and the timing of extractions of certain deciduous teeth aligns the teeth naturally as opposed to orthodontic mechanical movement of permanent teeth into alignment after they have erupted. Research shows that pre-eruption guidance produces far more stable tooth alignment than alternative treatments.

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.

Dr. William J. Clark is a Scottish orthodontist known for developing Twin Block Appliance in Orthodontics. This appliance was developed by Dr. Clark in 1977 in Scotland and since then this appliance has been used in correction of Class 2 malocclusions with retrognathic mandible. He also developed invisible TransForce Appliance in 2004.

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

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.

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.

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.

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.

The Herbst appliance is an orthodontic appliance used by orthodontists to correct class 2 retrognathic mandible in a growing patient, meaning that the lower jaw is too far back. This is also called bitejumping. Herbst appliance parts include stainless steel surgical frameworks that are secured onto the teeth by bands or acrylic bites. These are connected by sets of telescoping mechanisms that apply gentle upward and backward force on the upper jaw, and forward force on the lower jaw. The original bite-jumping appliance was designed by Dr. Emil Herbst and reintroduced by Dr. Hans Pancherz using maxillary and mandibular first molars and first bicuspids. The bands were connected with heavy wire soldered to each band and carried a tube and piston assembly that allowed mandibular movement but permanently postured the mandible forward. The appliance not only corrected a dental Class II to a dental Class I but also offered a marked improvement of the classic Class II facial profile.

References

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  2. Peck, Sheldon (Nov 2009). "A biographical portrait of Edward Hartley Angle, the first specialist in orthodontics, part 1". Angle Orthod. 79 (6). United States: 1021–7. doi: 10.2319/021009-93.1 . ISSN   0003-3219. PMID   19852589.
  3. King, Sam (18 January 2015). "The History of Orthodontic Technology". King Orthodontics. Retrieved 4 April 2015.
  4. 1 2 3 4 MITCHELL L. (2007). An introduction to orthodontics. 3rd ed. Chapter 19: Functional appliances. Pg 203-215.
  5. 1 2 Children and Orthodontics: Types of Braces, Retainers, Headgear and Facemasks www.webmd.com/oral-health/guide/children-and-orthodontics WebMD describes common types of orthodontics for children, including braces headgear, and retainers.
  6. "Hanks Herbst Appliance | Dental Appliance". ODL Orthodontic Labs. Retrieved 2022-06-07.
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  8. 1 2 3 CLARK W. (2010). Design and management of Twin Blocks: reflections after 30 years of clinical use. Journal of Orthodontics. 37: 209-216.
  9. 1 2 O’BRIEN K. et al. (2003). Effectiveness of early orthodontic treatment with the Twin-block appliance: a multicentre, randomized, controlled trial. Part 2: Psychosocial effects. American Journal of Orthodontics and Dentofacial Orthopedics. 124(5): 488-494.
  10. O’BRIEN K. et al. (2003). Effectiveness of treatment for Class II malocclusion with the Herbst or twin-block appliances : a randomized, controlled trial. American Journal of Orthodontics and Dentofacial Orthopedics. 124(2): 128-137.
  11. TULLOCH J.F., PHILLIPS C. and PROFFIT W.R (1998). Benefit of early Class II treatment: progress report of a two-phase randomized clinical trial. American Journal of Orthodontics and Dentofacial Orthopedics. 113: 62-72.
  12. Hohmann, Arnold (2014). Foundations of dental technology. Anatomy and physiology. Werner Hielscher. Hanover Park, IL. ISBN   978-0-86715-688-1. OCLC   887737816.{{cite book}}: CS1 maint: location missing publisher (link)
  13. Clinical applications of digital dental technology. Radi Masri, Carl F. Driscoll. Ames, Iowa. 2015. ISBN   978-1-118-98302-7. OCLC   904400171.{{cite book}}: CS1 maint: location missing publisher (link) CS1 maint: others (link)
  14. 1 2 Tarraf, Nour Eldin; Ali, Darendeliler M. (2018-12-01). "Present and the future of digital orthodontics✰". Seminars in Orthodontics. Digital Technologies In Orthodontics – An update. 24 (4): 376–385. doi:10.1053/j.sodo.2018.10.002. ISSN   1073-8746. S2CID   81046374.
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