Abstract: A teeth grinding preventing device to be put in an oral cavity of a user includes a main body portion formed into a substantially arcuate shape along a curve of a maxillary teeth alignment of the user and configured to cover an occluding surface of the maxillary teeth, a sensor portion embedded in the main body portion to extend in parallel to the occluding surfaces of maxillary and mandibular teeth and configured to detect an occlusal force and output a detection signal, a teeth grinding determining portion configured to receive the detection signal and determine whether or not the user is grinding the teeth, and a stimulation providing portion configured to provide the user with a stimulation when the teeth grinding determining portion determines that the user is grinding the teeth, and the stimulation providing portion is provided to be mountable and demountable with respect to the main body portion.

Abstract: Simultaneous measurement of a border position of a mandible joint opening and the "end-feel" force required to achieve the border position are effectuated through a single apparatus which applies a force to the upper and lower jaw of a patient and continuously measures the degree of opening of the jaw as the mandible joint opens. When a predetermined amount of force is achieved as measured by either a detected degree of spring compression within the device or release of a detent mechanism, the force is automatically or manually withdrawn leaving an indicator showing the maximum jaw opening. Simultaneous border position and "end-feel" force can also be measured in alternative embodiment through reverse scissors and a mechanical dial and slider for continuously measuring the degree of opening while an electrical transducer measures the force applied until the "end-feel" force has been achieved as digitally read out.