Method of evaluating an orthodontic appliance

A method for evaluating an orthodontic appliance worn by a patient, said method comprising the following steps:

• 1′) at an “appliance” instant, acquisition of at least one two-dimensional image of teeth of said patient, said image, referred to as “appliance image”, at least partially representing the orthodontic appliance in a service position in which it is worn by said teeth;
• at a “dentition” instant, acquisition of at least one two-dimensional image of said teeth of said patient, referred to as “dentition image”;
• 2′) if a determination of comparable dental and appliance attributes relative to the shape of a tooth represented on the at least one dentition image and relative to the shape of the orthodontic appliance on the at least one appliance image, respectively, is not possible from said at least one appliance image and from said at least one dentition image, respectively, conversion of at least one image chosen from the at least one appliance image and the at least one dentition image so that said at least one appliance image be compatible with said at least one dentition image;
• for each of a plurality of teeth represented on the at least one dentition and appliance images:
• 3′) determination of said dental and appliance attributes, the dental and appliance attributes at step 3′) being:
• an outline of the tooth and of the orthodontic appliance on the dentition and appliance images respectively, or
• a surface of the tooth and of the orthodontic appliance, respectively, determined from a plurality of dentition images and from a plurality of appliance images, respectively;
• 4′) comparison of the dental and appliance attributes, followed by determination of at least one score according to said comparison, said step 4′) comprising the following steps:
• for each of a plurality of teeth for which the dental and appliance attributes have been determined;
• i) determination of a distance between the dental and appliance attributes;
• ii) determination of a distance threshold;
• iii) for each of said teeth, determination of a distance score dependent on
• the distance between the dental and appliance attributes, and
• the distance threshold;
• at least one image chosen from of said at least one appliance image and said at least one dentition image being acquired with a mobile phone by the patient or another person.