Treatment of open bite and deep bite at the Center for Oral, Maxillofacial and Facial Surgery

With these malpositionings of the jaws the vertical height of the bite is very important and affects the biting function and facial esthetics. Due to the growth pattern of the jaws the open bite is usually shown by a long face and the deep bite by a short face – in connection with the appropriate functional problems.

Open bite

In cases of an open bite the upper jaw has developed too narrow and too far down towards the lower jaw due to uncoordinated growth and has thus negatively influenced growth of the lower jaw. This results in a malocclusion with malpositioned teeth – a so-called scelettally open bite. Mostly these are severe malocclusions.

The open bite often comes with crooked teeth, lots of visible gums and a distal position of the lower jaw. This means that most of the time the lips cannot be easily laid together when the mouth is closed (lip closure incompetence). In addition, the biting function is impaired, the pronounced oral breathing is combined with restricted nasal breathing and causes dry mucous membranes and lips, caries susceptibility of the teeth, gum diseases and an increase of infectious diseases.

Changes of the temporomandibular joints can also cause an open bite so that temporomandibular joint diagnostics are indicated. In addition, a tongue malfunctioning, such as, for instance, an altered swallowing pattern or tongue pressing can be excluded or treated.

An accurate analysis is very important for the planning of the treatment and stability of the treatment results.

In cases of an open bite, improvement of the occlusion solely by moving the teeth (dental compensation), i.e. orthodontic reduction of the distance between teeth of the upper and lower jaws as well as widening of the maxillar arch should be avoided. Once the fixed braces are removed the occlusion may open again – there is a risk of recidivism.

The open bite is often accompanied by crooked teeth, a lot of visible gums and a backward dislocation of the mandible. Most of the time the lips cannot lie next to each other in a relaxed way when the mouth is closed (mouth closure incompetence). In addition, the biting function is impaired, the pronounced mouth breathing is combined with impaired nasal breathing and causes dry gums and chapped lips, susceptibility for tooth decay, gum diseases and a high frequency of infections.

Changes in the temporomandibular joints may also lead to an open bite so that temporomandibular joint diagnostics are indicated. Furthermore, a tongue malfunction, such as an altered swallowing pattern or tongue pressing, must be excluded or treated.

An accurate analysis is of great importance for planning the treatment and for the stability of the treatment results.

In an open bite, improvement of the bite solely by tooth movements (dental compensation), i.e. by orthodontic reduction of the distance between upper and lower teeth as well as widening of the maxillary arch should be avoided. Once the braces are removed the bite might open up again – there is a risk of relapse.

Deep bite

In cases of a deep bite the upper jaw has developed too narrow and insufficiently towards the lower jaw due to uncoordinated growth and in addition negatively influenced growth of the lower jaw. The result is a malocclusion. The teeth of the lower jaw are hidden deeply underneath those of the upper jaw.

The deep bite comes with a loss of occlusion height and, consequently, also of facial height since there is a pronounced difference in the levels of anterior and posterior teeth of the lower jaw, Compared to the posterior teeth the anterior teeth are perceptibly higher. In addition, there is a distal position of the lower jaw (angle class II/1 or angle class II/2). This causes the lowest third of the face to appear reduced in comparison with the middle face and the forehead, so that forehead and the region of the nose appear larger. On the whole, the teeth are less visible.

Due to the deep bite and the distal mandible the condyles are often pushed far to the back (forced bite with locking phenomenon) so that temporomandibular joint problems with clicking (disc relocations) may appear. Tooth gnashing (bruxism) may cause straining of the chewing muscles with muscle hypertrophy (e.g. masseter hypertrophy) and muscle tenseness. This in turn will cause a widening of the jaw angle contours and make the face appear wider.