The human jaw consists of a maxilla and a mandible. The jaws are part of the skull. The lower jaw is a U-shaped bone attached to the temporal bone by the temporomandibular joint. At the anterior part of the lower jawbone, part of the masticatory muscles begin. Through the jaw joint of the lower jaw bone is movable.
The upper jawbone is the largest bone of the midface. Partially, the upper jawbone is hollow. The cavities within the bone are part of the paranasal sinuses and are called maxillary sinuses. In contrast to the lower jaw, the upper jaw is immobile. Teeth are anchored in the jaws of the jawbone.
A bite is the interlocking of maxillary and mandibular teeth. The bite position, in turn, is a location statement that provides information about how the two jawbones are related to each other. The physiological bite is called a neutral bite or as a standard bite. Mandible and maxilla are in a normal relationship both with each other and with the entire skull.
A normal bite condition is a prerequisite for a physiological chewing process. Chewing requires optimal coordination between jawbone, masticatory muscles, teeth and temporomandibular joints. The buying function is reflexive. The necessary for the chewing movements performs only the lower jaw. In the process, fast fine tuning through the jaw musculature is constantly carried out.
In normal bite, the teeth have contact only when chewing, biting and swallowing. Due to the high pressure load during the chewing process, it is important that a vertical load of the teeth takes place.
The teeth are suspended in collagen fibers in the jaws of the jawbone. The pressure acting on the tooth during chewing is converted into a tensile load of the bone. With an optimal bite position, chewing stimulates bone build-up in the jawbone. Conversely, the lack of pressure in a malposition can lead to bone loss.
A physiological bite allows humans to effectively break down the food they feed and thus prepare them optimally for digestion. The teeth are not only chewing tools, but also speech tools that are involved in the formation of sounds. A normal bite allows you to speak without hissing, whistling or lisping.
Incidentally, the dental and jaw apparatus also fulfills a social function. Healthy and straight teeth as well as a straight jaw position are perceived as beautiful and desirable and are considered a social figurehead. Frequently, a corresponding social status is associated with the condition and position of the teeth.
If the upper and lower jaw are in a pathological positional relationship, this is called a false bite or a wrong bite position. If the lower jaw is displaced to the rear, a Distalbiss arises. The distal bite is also referred to as a lower reserve. Seen from the front, the lower arch then lies behind the upper arch. The distal bite is also known as a frontal overbite or scissor bite. In the vernacular one speaks of hare teeth or a fleeing chin.
The opposite of the distal bite is the so-called mesial bite. Here are the upper incisors, resulting in a frontal overbite. Lower incisors, which bite in front of the upper incisors, form a Vorbiss. The classification of malocclusions is done in Angle classes. Distal bites belong to class II, mesial bites to class III.
The causes of dental and jaw malformations are manifold. Frequently, the anomalies are inherited, for example, in conjunction with a cleft lip and palate. Also hormonal causes are conceivable. For example, acromegaly can result in a change in the bite position. In acromegaly, the growth hormone somatotropin is increasingly formed. Among other things, it comes to a bony growth in the chin area.
Malocclusions can also be acquired. Constant finger sucking or the pacifier in infancy as well as dysfunctions during the swallowing process can lead to an altered bite position. Likewise, infectious diseases or chronic vitamin deficiency are possible causes of a pathological bite.
Even small misalignments of the jawbone can cause considerable damage. Due to the wrong positional relationship, there is an incorrect load on the teeth, the jawbone and the masticatory muscles.
Chewing causes great forces. The chewing pressure in humans is at the food shredding at 20-30Kp / cm². In a normal bite position, the pressure is evenly distributed. With a forward or backbite this optimal pressure distribution is no longer guaranteed. The constant overuse of certain areas of the jaw can lead to a jaw clamp. In this case, the mouth can not be fully opened. Also, a jaw lock as a result of a false bite situation is conceivable. A jaw lock prevents the mouth from closing.
Facial pain, headache and back pain can be caused by a jaw malposition. Due to the malfunction of the jaw, the chewing and facial muscles become tense. The neck muscles are also strained. Not infrequently, the cause of a migraine in the jaw area.
The uneven pressure distribution also affects the teeth. The teeth may prematurely die or fall out. Perhaps the pathological bite even manifests itself in digestive problems. If biting and chewing are not properly possible due to the malposition, the food is only insufficiently minced. This can lead to problems in the gastrointestinal area. If the mouth can not close properly due to the bite, breathing is usually through the mouth. Dry mucous membranes and an increased susceptibility to infection are the result. Depending on the bite situation, it can also lead to speech disorders.