抄録
Occlusion, together with the morphology and position of the teeth, changes throughout a person's life. It also seems quite natural that deviation of the mandible occurs in conjunction with these changes. Observation of this phenomenon in mature adults over a period of ten years clearly shows that this is an aspect of physical health that can readily be confirmed by anyone. The extent of these changes is generally small in dentate individuals.
In order to determine whether the situation should be considered a disease state, it is important to carefully investigate whether the oral tissues and function deviate from normal human physiological limits. However, when we carry out the same observations on an oral cavity where several teeth have been lost, it becomes obvious that these changes have accelerated. These effects are often seen in cases where treatment was done without a thorough evaluation and diagnosis of the dentition with missing teeth, and can be considered the result of the long-term use of a poor prosthesis that was provided. This can occur because the most important task of the oral cavity as an organ is mastication, and the surrounding tissues attempt to adapt to accomplish this task even though there is malocclusion. Maintenance of masticatory movements in this way result in deviation of the mandibular position owing to training of the muscles of mastication, and often creates establishment of a pathologic mandibular position.
Although it is necessary to return the mandible to its normal physiologic position and movements, the methodology for this is in no way simple. In this particular case, I searched out the reasons for the patient's mandibular deviation, and using the evaluation and diagnosis of a dentition with missing teeth as a basis, present here in detail the thought process involved in the treatment and selection of the necessary target mandibular position for establishment of a physiologic occlusion.
