Abstract: A method for evaluating, by computer, at an “updated” time, the conformity of an orthodontic aligner with a dental arch of a patient, referred to as the “support arch.” The method includes the following successive steps: A) producing a digital three-dimensional model of the support arch in its configuration at the updated time, or an “updated reference model”, and determining from the updated reference model, a support surface for the aligner; B) deforming the support surface on the basis of the geometry of the aligner in order to obtain a deformed support surface; C) comparing an external surface of the aligner with the deformed support surface, then determining, on the basis of the comparison, at least one score for the conformity of the aligner with the support arch.