Bite or dental occlusion as it is also known is the normal spatial relation of the teeth when the jaws are closed. Occlusion is influenced by three primary components teeth nerves and muscles and bones all working together to produce the best bite possible. Another factor which can affect the way your teeth come together is your posture.
The term centric occlusion is used to define the normal position of a closed jaw. An ideal centric occlusion is when all the teeth are in proper contact with no cross bite or any under bite or over bite. In order to achieve this centric occlusion different parts of the teeth and mouth structure work together to guide the jaw.
In an ideal occlusion when the lower jaw is shifted to one side the posterior teeth should not touch. To achieve this a process called canine guidance or canine protected occlusion occurs where the lower canine or eyetooth rides up on the upper canine. When the canines touch nerves send a message back to the brain which in turn sends a message to large muscles that lose the jaw. This is a biofeedback mechanism that causes the muscles to relax. If this canine protection or biofeedback mechanism is removed the muscles stay active. This is the reason for teeth clenching grinding of the teeth joint pain fracturing of teeth excessive wear of the enamel on top of the tooth erosion of the root surface (abfractions) and gum recession. If teeth are properly aligned all the components that make up the occlusal system (teeth nerves muscles and bones) should function in harmony. Normal chewing places approximately 68 lbs/sq inch of pressure on the back teeth. Intentionally clenching your teeth you may increase that force to about 150 lbs/sq inch
Another mechanism that interacts to produce a proper bite posture is known as Anterior Guidance. In a normal bite the anterior (front) teeth guide the posterior (back) teeth into position or centric Occlusion. When the front teeth are placed together on their biting edges the posterior teeth should not touch.
Some individuals front teeth do not touch at all and they have what is called an anterior open bite or an overbite. This is due to bony (skeletal) discrepancy between their upper and lower jawbones. Sometimes this can be corrected by a combination of orthodontics surgery to reposition the bones and/or crowns (caps).
Symptoms of a non-perfect occlusion are very easy to spot and include the following problems.
Heavy wear facets on the biting surface of the teeth. Receding gum tissue Erosion/notching of the root surfaces (abfractions) Cracked/fractured teeth Front teeth do not touch Pain in the joint and muscles Erosion of the biting surfaces of the back teeth loss of enamel Clenching or grinding of the teeth
