Bite Analysis in Dentistry
A bite analysis is used to determine the position of the lower jaw in relation to the upper jaw.
With regard to its position vis-à-vis the upper jaw, the lower jaw is not positioned in a permanent fashion; i.e., its optimal position is recalculated over and over by the brain based on data supplied by small receptors in the periodontal apparatus, the musculature, and the jaw joint. Thus, the masticatory apparatus is able to adjust very quickly to the wearing down of the teeth and to tooth loss. In most cases, you only notice the phenomenon of the variable position of the lower jaw in the morning. Many people sleep with their mouth open at night, thus erasing the “optimal” position of the lower jaw in the brain. The result is a feeling in the morning that your teeth don’t fit together with one another. It’s only after a few chewing movements that our brain rediscovers the correct jaw position by means of these sensitive receptors; then we can begin the day. If the lower jaw is “pressed” into an unfavorable position, e.g., due to a bad dental prosthesis, it can cause facial pain, jaw joint pain, and even headaches.
In individuals with a full set of teeth, the position of the jaws is determined by the dentition. In persons without any teeth or with very few teeth, the dental technician needs information about how the jaws relate to one another in order to be able to correctly prepare the dental prosthesis. A bite analysis will demonstrate the jaw relationship to the technician. There are numerous techniques for taking a bite analysis. You see one of them here: First, the patient bites into a cotton roll for 10 minutes, so that memory – our brain – is deprogrammed.
Afterwards, the practitioner grabs the patient’s lower jaw through a special grip and closes it, thereby pushing the mandibular condyles to the upper front. However, this technique should only be used in patients, who – due to severely reduced teeth – don’t possess a clear dental arch and whose lower jaw cannot be positioned in a reproducible fashion.
During the bite analysis procedure, a silicone squeezer is placed between the two toothless/sparsely toothed jaws. Based on the impressions of the jaw ridges in the squeezers, the technician can roughly position the plaster models and prepare a bite splint. With the aid of the bite splint, a second bite analysis is performed, during which the patient wears the bite splint instead of the squeezer. Thus, the determination of the jaw position is even more accurate.
Nowadays, it’s assumed that the ideal position of the mandibular condyles in the large joint socket is at the “top front;” therefore, one attempts to achieve this position in the lower jaw during the reconstruction of the bite. In the past and even today sometimes, the lower jaws of many patients with teeth were/are forced into a “target position” by means of new dentures and/or the cutting of the teeth. This makes no sense whatsoever. A bite analysis of patients with a good set of teeth and of those without complaints is unnecessary, because the individual’s bite results from the dentition of the teeth.
Although it may deviate from the “ideal” bite, this fact doesn’t matter at all. Thus, a bite analysis only makes sense if there’s a lack of reference points, i.e., in case of a severely reduced bite or a toothless patient. It’s very rare that a new bite is sought in patients with a full set of teeth – e.g., in those with facial and/or jaw joint disorders. For such purposes, the remaining teeth must be cut to accommodate the new bite situation.
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