Method for training a neural network to determine at least one value of a tooth attribute relating to a tooth represented on an analysis image, said method comprising enrichment of a learning base so as to acquire a plurality of historical images, and then use of said learning base to train said neural network, said enrichment method being characterized in that it comprises the following steps: A) at an instant called "updated" instant, production of a digital three-dimensional model of a dental arch of a patient, or "updated reference model", and segmentation of the updated reference model so as to produce, for each tooth, a digital three-dimensional tooth model, or "tooth model", and, for at least one tooth attribute, assignment of a tooth attribute value to each tooth model; B) acquisition of at least one image of said arch, or "updated image", in real acquisition conditions; C) for each updated image, search for virtual acquisition conditions suitable for an acquisition of an image of the updated reference model, called "reference image", exhibiting a maximum match with the updated image in said virtual acquisition conditions, and acquisition of said reference image; D) identification, in the reference image, of at least one zone representing a tooth model, or "reference tooth zone" and, by comparison of the updated image and of the reference image, determination, in the updated image, of a zone representing said tooth model, or "updated tooth zone"; E) assignment, to said updated tooth zone, of the one or more tooth attribute values of said tooth model; F) addition of the updated image enriched with a description of said updated tooth zone and its one or more tooth attribute values, said enriched updated image being called "historical image", in the learning base. A) at an instant called "updated" instant, production of a digital three-dimensional model of a dental arch of a patient, or "updated reference model", and segmentation of the updated reference model so as to produce, for each tooth, a digital three-dimensional tooth model, or "tooth model", and, for at least one tooth attribute, assignment of a tooth attribute value to each tooth model; B) acquisition of at least one image of said arch, or "updated image", in real acquisition conditions; C) for each updated image, search for virtual acquisition conditions suitable for an acquisition of an image of the updated reference model, called "reference image", exhibiting a maximum match with the updated image in said virtual acquisition conditions, and acquisition of said reference image; D) identification, in the reference image, of at least one zone representing a tooth model, or "reference tooth zone" and, by comparison of the updated image and of the reference image, determination, in the updated image, of a zone representing said tooth model, or "updated tooth zone"; E) assignment, to said updated tooth zone, of the one or more tooth attribute values of said tooth model; F) addition of the updated image enriched with a description of said updated tooth zone and its one or more tooth attribute values, said enriched updated image being called "historical image", in the learning base. <EOS>