The Effect of Time and Force Magnitude on Orthodontic Tooth Movement

Abstract
The holographic technique, recently developed for precise and accurate measurement of tooth displacements, was used to study the three-dimensional motion of human teeth. Maxillary central incisors were loaded with forces of 300 grams and 500 grams. Translations and rotations in three-dimensions were measured over 45 seconds. The experimental results, presented as a function of time, indicate that the instantaneous centers of rotation can be represented by space centrodes that are characteristic for each patient and the applied force system.