Holographic Investigation of Tooth Deformations

Abstract

A bad approximal contact may cause food impactions between teeth by masticatory forces. This may give rise to caries or other paradental diseases. Many studies on approximal contact relation have been presented based on clinical experience [1] and considered from a morphological standpoint [2] up to now. However, there have been only few studies on approximal contact relation investigated from a functional viewpoint. Therefore, investigations of the deformations of teeth subjected to occlusial or masticatory forces and the mechanical effect to their adjacent teeth are very important. Deformations have been measured, until now, with mechanical instruments [3], [4] such as dial gauges and strain gauges. Recently, double-exposure holographic interferometry has been found useful to measure three-dimensional deformations of teeth [5], [6]. This method, however, is restricted to the measurement of deformations within a certain time interval. Real-time holographic interferometry, on the other hand, allows measuring such deformations continuously.