<unk> ing in (A) shows the effect of oral seal to enable nasal breathing whilst awake , whereby lack of<unk>  (B) ensures obligate oral breathing. When asleep in a supine position,<unk>  tone is lost, potentiating both oral and nasal airflow blockage (C). This is relieved by drawing both the collapsed<unk>  (glossoptosis) and small jaw forward through dependent thumb sucking, enabling normal nasal breathing. Diagram obtained from Coceancig, Paul. 6Ways To Design A Face: corrective jaw surgery to optimize bite, airway, and facial balance. Batavia: Quintessence Publishing. .<unk>  (also called reverse swallow or immature swallow) is a pseudo-pathological name of what is either considered a normal adaptive lip seal mechanism, whereby normal nasal breathing or normal swallowing can occur. Or, it is seen as an oral myofunctional disorder - a<unk>  muscle pattern that is perceived as clinically abnormal and in which the<unk>  protrudes anteriorly to seal otherwise incompetent lips.<unk> ing is only seen during speech, swallowing or eating, and in order to close otherwise incompetent lips on background of an almost ubiquitous small lower jaw and anterior open bite. The behaviour is apparent only during a normal awake state, and whilst the<unk>  (and rest of the body) is in normal resting tone. By descriptive inference,<unk> ing is impossible during deep sleep, or non-tone phases; or in particular during non-conscious states. Nearly all infants exhibit a swallowing pattern involving forward<unk>  tip push as part of infant suckling behaviour . By six months of age most lose the forward extent of this push once paediatric incisal teeth erupt, and normal lip seal is automatically acquired as solid foods begin. There are thus two community and clinical professional views of the observation of<unk> ing behaviour that persists past the neonatal period. 1. Either it is a normal adaptive means of closing an open (or incompetent) lip state, caused by a unique combination of anatomical reasons, or 2.<unk> ing is the cause or potentiator of an open or incompetent lip state, and which resists efforts at behavioural change or clinical attempt at remedy. In generality,<unk> ing is poorly understood. In particular it lacks consensus on many points of description, causality, effect or management and between the various clinical groups that each offer different forms of treatments or philosophies of professional interest. The Classical view of<unk> ing == Since 1958, the term<unk> " has been described and discussed in speech and orthodontic (dental) publications and by a range of writers - and speaking from specific non-medical professional perspectives and clinical biases - as a pathological event that exists as an entity for itself and without fundamental or primary functional or necessary cause. Both the general dental and speech pathologist classical views are that<unk> ing causes both the dentofacial abnormality of anterior open bite, and the incompetent lip seal and swallowing and speech effects associated with<unk> . In both professions,<unk>  is represented as a behavioural disturbance which can be taught to be resisted. Such interventional therapy is represented to strongly assist orthodontic or speech pathologist efforts at resolution of both the speech and orthodontic effects of anterior open bite and the associated lip incompetence of both. As with normal reflexes, most school-age children have<unk>  if looked for. For example, according to recent literature, as many as 67–95 percent of children 5–8 years old exhibit<unk> , which may professionally be represented as associated with or contributing to an orthodontic or speech problem - depending on the clinical bias of proposal. Up to the age of four, as with the complex conversion of all simpler reflex events, there is a possibility that any observed child will normally outgrow<unk>  as they transition to a fuller dentofacial development. However, if a<unk>  pattern is retained beyond infancy, it can be seen through a lens of abnormality, and this vulnerable to clinical bias and attempts to clinically interact. Types of<unk> ing include: ;Anterior<unk>  :This is the most common type of<unk> . It is often associated with a low, forward<unk>  rest posture. Sometimes the<unk>  can be seen protruding beyond the lips at rest and/or during the swallow. Upper incisors can be extremely protruded and the lower incisors are pulled in by the lower lip. An anterior open bite is a common malocclusion associated with this type of<unk> ing pattern, especially in the presence of lip incompetence. This type of<unk>  is most generally accompanied by a strong mentalis. ;Unilateral<unk>  :This occurs when the<unk>  pushes unilaterally to the side between the back teeth during the swallow. The bite can be characteristically open on that side. ;Bilateral<unk>  :This occurs when the<unk>  pushes between the back teeth on both sides during the swallow with the jaw partially or subtly open. Sometimes, the only teeth that touch are the molars, with the bite completely open on both sides including the anterior teeth. A large<unk>  can also be noted. This is the most difficult<unk>  to correct.
Tongue thrust
Concussion
Nose-blowing
Pressure of speech
Arytenoid adduction
Sidaction
Sinus lift
Cramp