Tooth movement sensor for clinical use

The examination of tooth mobility is important in estimating the condition of the periodontium. The authors previously reported on a transducer for measuring the stiffness of the human skin, and have applied its principle to the measurement of tooth mobility. The tooth movement sensor developed is built into a simple and portable "T-M (tooth mobility) tester". In this tester, a sinusoidal vibration is applied to the tooth crown, the acceleration response is detected, and the MI (mobility index) corresponding to the tooth movement is obtained. The measurement conditions, such as the contact preload on the tooth crown and the actuating direction of the measuring probe, are also studied. The tooth mobility of artificial tooth models and the diurnal variation in physiological tooth mobility are also measured.