Determine an amount of movement between an “anterior” updated instant and a “posterior” updated instant after the anterior updated instant. At the anterior updated instant, implementing an analysis method to obtain an anterior updated item of spatial information. Analyze a set of several images to obtain spatial information. Create a historical learning database relating to a dental body and the spatial attribute, with a set of historical images all depicting the dental body and an item of spatial information. Training the neural network, by providing the sets of several historical images as input and with the historical spatial information as output, with the spatial attribute defining an ordered sequence of variables in a three-dimensional reference frame. At the posterior updated instant, implement analysis to obtain a posterior updated item of spatial information. Compare the anterior and posterior updated spatial information, to obtain an amount of movement.