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THE TREATMENT REGISTRY
Patient journey

Jaw malocclusion

By The Treatment Registry editors

Misalignment between the upper and lower jaws — Class II (retrognathic mandible), Class III (prognathic mandible), open bite, or asymmetric — producing functional and aesthetic concerns. Treatment combines orthodontics and, in moderate to severe skeletal cases, orthognathic surgery.

Clinical overview

Signs and symptoms

Malocclusion is a misalignment or incorrect relation between the teeth of the upper and lower dental arches when the jaws close. It is a common finding that is not usually serious enough to require treatment, but more severe malocclusions, including those presenting as part of craniofacial anomalies, may require orthodontic and sometimes orthognathic surgical treatment. Reported consequences include tooth decay and periodontal disease arising from difficulty maintaining oral hygiene, an increased risk of trauma to anterior teeth where the overjet exceeds 3mm, difficulty chewing with anterior open bites or large increased and reverse overjet, speech impairment such as a lisp, tooth impaction, and effects on psychosocial well-being. Skeletal disharmony between the upper and lower jaws can distort facial shape and impair mastication and speech.

Causes and risk factors

The aetiology of malocclusion is multifactorial, with both genetic and environmental influences, and three causative factors are generally recognised. Skeletal factors concern the size, shape and relative positions of the upper and lower jaws; variations can arise from environmental or behavioural factors such as a childhood diet of soft, cooked food (producing smaller jaws), nocturnal mouth breathing, and cleft lip and palate. Muscle factors relate to the form and function of the muscles surrounding the teeth, influenced by habits such as finger sucking, nail biting, pacifier use and tongue thrusting. Dental factors include the size of the teeth relative to the jaw, and early loss of teeth causing spacing or crowding, abnormal eruption, hyperdontia or hypodontia.

How it is diagnosed

Malocclusion is defined as any deviation of the occlusion from the ideal. Its classification, popularised by Edward Angle, is based on the relationship between the mesiobuccal cusp of the maxillary first molar and the buccal groove of the mandibular first molar; if this molar relationship is correct, the teeth can align into normal occlusion. Assessment should also take into account aesthetics and the impact on function, and where these are acceptable to the patient despite the formal definition being met, treatment may not be necessary. Severe malocclusions, which may present with skeletal disharmony between the jaws as part of craniofacial anomalies, generally require orthodontic and often orthognathic surgical evaluation.

Who it affects

Malocclusion is a common finding in the population, although it is not usually severe enough to require treatment. It is estimated that nearly 30% of the population has malocclusions that are categorised as severe and would definitely benefit from orthodontic treatment. Malocclusion can occur in both primary and secondary dentition.

Clinical overview sourced from encyclopaedic medical reference; see sources below. General information only — not a substitute for individual clinical assessment.

Treatment ladder

Conservative options are first-line where appropriate; surgical options are typically reserved for cases where lower-tier options are unsuitable or have failed. Decisions are individual and depend on clinical assessment.

Conservative

  • Orthodontics alone

    Fixed or clear-aligner orthodontics can address mild skeletal discrepancy and most dental malocclusion. Treatment time is typically 12-36 months.

Procedural

  • Orthodontics with skeletal anchorage

    Temporary anchorage devices (mini-implants) enable orthodontic movement beyond what brackets alone achieve. Useful in borderline cases between orthodontics-only and surgery.

Surgical

  • Orthognathic jaw surgery · View procedure page

    Single-jaw (maxillary or mandibular) or double-jaw surgery, typically preceded and followed by orthodontic treatment. The standard treatment for moderate to severe skeletal malocclusion; outcomes can be marked but operative and recovery time are substantial.

Related procedures

Sources

  1. [1]WHO Surgical Safety Checklist — who.int(accessed 2026-05-09)
  2. [2]Wikipedia — Malocclusion — en.wikipedia.org(accessed 2026-07-24)

Sources marked “on file” are held by The Treatment Registry but are not publicly accessible.