Abstract: A tooth mobility measuring apparatus of this invention includes an impact mechanism which injects or sucks a fluid to apply an impact to a tooth, a sensor which detects the displacement state of the tooth which is moved by the impact force from the impact mechanism, and a tooth mobility calculation mechanism which calculates the tooth mobility of the tooth on the basis of the output signal from the sensor. The displacement state of the tooth is measured without touching the tooth.

Abstract: An automatic selection apparatus for sheet material can automatically distinguish whether sheet materials such as sheets of paper are good or bad. While the sheet materials are carried one by one in the direction perpendicular to the flow direction in the manufacturing process or working process of the sheet materials with a leading edge thereof being held by a gripper, an optical type defect detection device detects a defect in the sheet material. Accordingly, vibration of the sheet material is avoided and the defect can be accurately detected. A controller receives a signal from the defect detection device and drives a switching device which opens and closes the gripper at a defective sheet discharged portion or a good sheet stacked portion.