Misaligned teeth

Classification according to ICD-10
K.07	Dentofacial abnormalities (including improper occlusion)
ICD-10 online (WHO version 2019)

Skeletal and dental malalignment

A tooth misalignment is any position of a tooth outside the ideal arch shape of the upper or lower jaw, which is aesthetically negative or causes a dysfunction (malfunction) in the occlusion . A distinction is made between dental misalignments ("teeth are wrong", malocclusion ) and skeletal malpositions ("size or position deviations of the facial skeleton") and combinations of both.

classification

The sagittal position of the jaws in relation to each other is divided into angle classes. On the other hand, misaligned teeth are defined in terms of their angulation to the occlusal plane . Finally, misaligned teeth are also defined by the occlusion curve ( Spee curve , compensation curve ) if z. B. there is no occlusion curve, but a straight occlusal plane.

In the neutral occlusion, the maxillary arch overlaps the mandibular arch. If teeth bite directly into one another, this is called a head bite ; If the lower jaw teeth lie further vestibularly than the upper jaw teeth, this is called a crossbite . Crossbite is mostly a transverse deviation; but it can also be a deviation in the sagittal (anterior teeth).

If the upper jaw lies more than the “normal” half tooth in front of the lower jaw, this is called prognathism (“teeth are in front”); if the lower jaw lies in front of the upper jaw, this is called progeny (“chin lies in front”).

Angle classes

The American orthodontist Angle defined occlusion in 1899. He started from the occlusal relationship of the six-year-old molars and drew conclusions about the positional relationship of the jaws to one another. Edwart Hartley Angle , Minneapolis, 1855–1930 is the founder of scientific orthodontics.

The division of the dentition anomalies after the occlusion of the first lower molars compared to the upper first molars is based on the Angle classification.

The finding of the bite position in the sagittal means at

• Class I: neutral bite
• Class II: distal bite
• Class III: mesial bite.

Angle class I.

The anterior cusp of the upper six-year molar occludes between the large cusps of the lower six-year molar (the six-year molar is the first molar that erupts behind the deciduous molar from the second dentition at around 6 years of age). This occlusion position is called neutral occlusion (in the sagittal area).

Angle class II / 1

The anterior cusp of the upper six-year molar occludes in front of the anterior cusp of the lower six-year molar. At the same time, the upper front teeth are clearly tilted forward (protruded). Often the maxillary arch is narrowed and the palatal vault is higher than usual. This (jaw!) Misalignment is often the result of thumb sucking for too long in childhood. The general rule is: soft tissue forms hard tissue. A relatively small force applied over a long period of time can definitely shape the (hard) bone, especially by influencing the growth in a certain direction. The latter is the core of any orthopedic treatment.

Angle class II / 2

The anterior cusp of the upper six-year molar occludes in front of the anterior cusp of the lower six-year molar. At the same time, the upper front teeth are strongly tilted (retro-inclined) palatally (towards the palate).

Angle class III

Example of an Angle class III (progeny): Ferdinand I. (HRR) as a young archduke. Many Habsburgs were pro-genetics . Progeny can be inherited. Note the clear step between the present incisors in the lower jaw and the upper jaw teeth. Today such a severe skeletal malformation would be corrected surgically .

.
The anterior cusp of the upper six-year molar occludes behind the second cusp of the lower six-year molar. The lower front teeth can stand in front of the upper front teeth - progeny .

Criticism of the system of angle classes and alternative systems

A main disadvantage of the classification according to the Angle system is the only two-dimensional view along a spatial axis in the sagittal plane in the final bite, although occlusion problems are basically three-dimensional. Deviations in other spatial axes, asymmetrical deviations, functional disorders and other characteristics relevant to therapy are not recorded. Another inadequacy is the lack of a theoretical foundation for this purely descriptive classification system. One of the other, much discussed weaknesses of the system is that it only considers static occlusion, that it does not take into account the origin and causes ( etiology ) of occlusion problems and does not take into account the proportions (or generally the relationships) of teeth and face. As a result, numerous attempts have been made to modify the Angle system or to replace it entirely with a more powerful one, but the Angle classification has so far been able to hold on primarily because of its simplicity and clarity. Well-known modifications of the Angle classification go back to Martin Dewey (1915) and Lischer (1912, 1933). Alternative systems have been proposed by Simon (1930, the first three-dimensional classification system), Salzmann (1950, with classification based on skeletal structures) and by James L. Ackerman and William R. Proffit (1969).

The cause of misaligned teeth and jaws

• Hereditary causes (inheritance)
• Hormonal causes (progeny, acromegaly)
• In connection with cleft lip and palate (inheritable)
• Acquired tooth misalignments through:
  • Malfunction (dysfunction) of the swallowing muscles, tongue motor skills
  • so-called habits (habits) such as finger sucking, pacifiers
  • Tooth extractions without subsequent prosthetic restoration
• Infectious diseases
• chronic vitamin deficiency

Consequences of misaligned teeth and jaws

• Misalignment of the teeth in the jaw
• Malformations of the teeth (irregular tooth growth )
• Misalignment of the lower jaw
• Incorrect development of the jaw ( dysgnathia ), e.g. B. Inhibition of growth of the upper jaw (maxillary retrognathy) with a cleft lip and palate . There are three phases in the development of the jaw that are particularly sensitive to influences and that can lead to undesirable development. These are the prenatal phase in the first trimester of pregnancy, the early postnatal phase up to the age of 4, and finally the last phase in puberty around the age of 14.
• Malformation of the jaw or facial muscles
• Improper loading of teeth, bones and muscles
• Tongue too big ( macroglossia )

Importance of misaligned teeth

1. Aesthetic meaning: As can be seen from the above photo, misalignments shape the profile, the aesthetic, sympathetic appearance as well as the facial expressions and expressiveness of the face very strongly or significantly .
2. Medical significance of tooth misalignments: Even small misalignments of teeth can permanently disrupt the occlusion, especially in terms of dynamics, and traumatize periodontia, the temporomandibular joints and the masticatory muscles.

therapy

→ Main article : Orthodontics

Orthodontic therapy can be carried out with removable or fixed devices. Regardless of this, a distinction must be made between influencing the skull and moving teeth.

species

A distinction is made between horizontal and vertical bite errors and transversal bite errors , which should be eliminated as far as possible by orthodontic treatment.

• Bad bite
  • Overbite ,
  • Underbite,
  • Crossbite ,
  • open bite,
  • Mesial bite ,
  • Distal bite
  • Cover bite
  • Overshot
• The rudiment of wisdom teeth
• Tooth misalignments in connection with cleft lip and palate
• in animals:
  • Bridging of the rodents

See also

• Temporomandibular joint

Web links

Commons : Orthodontics  - collection of images, videos and audio files

literature

• James L. Ackerman, William R. Proffit: The characteristics of malocclusion: A modern approach to classification and diagnosis . In: American Journal of Orthodontics, Vol. 56, Issue 5, November 1969, pp. 443-454
• Edward H. Angle : Classification of Malocclusion . In: Dental Cosmos. 1899
• Stephan Guyenet: Malocclusion: Disease of Civilization , part IV, in: Whole Health Source - Nutrition and Health Science, 2009
• Sridhar Premkumar: Prep manual for undergraduates: orthodontics . Reed Elsevier, New Delhi 2008, ISBN 978-81-312-1054-3 (English, limited preview in Google Book Search [accessed January 5, 2017]).
• Sheldon Peck: A Biographical Portrait of Edward Hartley Angle, the First Specialist in Orthodontics, Part 1. In: Angle Orthodontist, Vol 79, No 6, 2009
• Gurkeerat Singh: Textbook of Orthodontics. 704 pp., 2nd edition 2008, ISBN 978-81-89979-04-1 .

Individual evidence

1. ^ Angle EH: Classification of malocclusion. in: Dental Cosmos. 1899; 41. p. 248
2. ↑ Sheldon Peck, Biography of EH Angle Angle Orthodontist, Vol 79, No 6, 2009
3. ↑ Jörg A. Lisson, Orthodontic Diagnostic Seminar ( Memento from September 4, 2016 in the Internet Archive ) (PDF; 1.3 MB), Saarland University Hospital
4. ↑ Sridhar Premkumar : S. 127
5. ↑ Sridhar Premkumar : p. 123. (There is a list of 18 such approaches with further references at the end of the book.)
6. ↑ Gurkeerat Singh: Textbook of Orthodontics, pp. 163-170. With further references on p. 174.
7. ↑ Stephan Guyenet: Malocclusion: Disease of Civilization, Part IV (engl.)

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !