Method for predicting a dental situation

Abstract

A method for predicting a future dental situation for a patient. Acquiring historical data including at least: previous time point and context parameter values. Acquiring at a time point all the data related to the current dental situation, including at least: the current time point, context parameter values at the current time point, statistical analysis of the historical data and the current data, so as to predict, at a future time point, at least one future dental situation for the current patient. Depending on the future dental situation, (re)evaluation of the benefit of an orthodontic treatment. Steps may include creating a three-dimensional digital reference model, acquiring at least one two-dimensional image, analysing each updated image and creation, searching, for each updated image, and collecting data relative to the updated reference model and relative to the orthodontic appliance.

1 . A method for predicting a future dental situation for a patient, called “current patient”, said prediction method including the following steps:
 1) acquisition of data, called “historical data”, relative to more than 1000 past dental situations, called “previous dental situations”, each experienced, at a time point called “previous time point”, by a patient called “previous patient”, all the historical data relative to a previous dental situation including at least:
 said previous time point; 
 context parameter values at said previous time point, the context parameters including tooth positioning parameters of said previous patient; 
 
 2) acquisition at a time point, called “current time point”, of data relative to a dental situation experienced by said current patient, called “current dental situation”, all the data related to said current dental situation, called “current data”, including at least:
 preferably, said current time point; 
 context parameter values at said current time point, the context parameters including tooth positioning parameters of said current patient; 
 
 3) statistical analysis of said historical data and said current data, so as to determine, for at least one future time point and for at least one future dental situation for the current patient,
 presentation of a difference between the future dental situation for the future time point and a prediction of an anticipated dental situation for said future time point, the anticipated dental situation being anticipated at a time prior to the current time; 
 
 4) analysis of the results obtained at step 3) and, depending on said future dental situation, evaluation of the benefit of an orthodontic treatment or, if the current patient has an orthodontic appliance, called “current orthodontic appliance”, reevaluation of the orthodontic treatment of said current patient and, depending on said reevaluation, possible modification of the orthodontic treatment of the current patient. 
 
     
     
         2 . The method as claimed in  claim 1 , wherein the context parameters at said previous time point include:
 if the previous patient has an orthodontic appliance, called “previous orthodontic appliance”,
 at least one parameter of said previous orthodontic appliance relative to the class and/or conformation of the previous orthodontic appliance; and/or 
 at least one parameter on the orthodontic treatment environment to which the previous dental situation relates, called “previous orthodontic treatment”, chosen from among a pain coefficient, a cost, a duration, a number of orthodontist appointments and a probability of success, associated with said previous orthodontic treatment; 
   and/or   at least one functional parameter of the previous patient; and/or   at least one anatomical parameter of the previous patient other than the tooth positioning parameters; and/or   the age and/or sex and/or an identifier of said previous patient.   
     
     
         3 . The method as claimed in  claim 1 , wherein the context parameters at said current time point include:
 if the current patient has with a current orthodontic appliance,
 at least one parameter of said current orthodontic appliance relative to the class and/or conformation of the current orthodontic appliance; and/or 
 at least one parameter on the current orthodontic treatment environment to which the current dental situation relates, called “current orthodontic treatment”, chosen from among a pain coefficient, a cost, a duration, a number of orthodontist appointments and a probability of success, associated with said current orthodontic treatment; 
   and/or   at least one functional parameter of the current patient; and/or   at least one anatomical parameter of the current patient other than the tooth positioning parameters; and/or   the age and/or sex and/or an identifier of said current patient.   
     
     
         4 . The method as claimed in  claim 1 , wherein, at step 3), several future situations are determined, for a single future time point, and/or at least one future dental situation, for several different future time points. 
     
     
         5 . The method as claimed in  claim 1 , wherein, at step 3), the following is determined, for at least one, preferably for each said future dental situation, and/or for at least one, preferably for each said future time point,
 if the current patient has a current orthodontic appliance, values, at said future time point, of parameters of said current orthodontic appliance; and/or   values of tooth positioning parameters of said current patient at said future time point; and/or   a difference from a dental situation constituting an objective at said future time point; and/or   a cost for said future dental situation to be achieved; and/or   a pain coefficient for said future dental situation to be achieved; and/or   a probability that the predictions relating to said parameters of said current orthodontic appliance and/or the tooth positioning parameters of said current patient, and/or said cost and/or said pain coefficient will comply with reality.   
     
     
         6 . The method as claimed in  claim 1 , wherein, at step 3), several said statistical analyses are carried out, each time modifying said future time point, so as to predict future dental situations up to a future objective time point, and thus constitute a “potential orthodontic treatment” up to said objective future time point. 
     
     
         7 . The method as claimed in  claim 6 , wherein several potential orthodontic treatments are determined, by changing one constraint each time. 
     
     
         8 . The method as claimed in  claim 7 , wherein first and second potential orthodontic treatments are determined which lead, for at least one tooth positioning parameter of the current patient, to extreme dental situations for said objective future time point, an extreme dental situation corresponding to a minimum or maximum limit for said tooth positioning parameter of said current patient. 
     
     
         9 . The method as claimed in  claim 8 , wherein the evolution over time of the value of said positioning parameter for the first and second potential orthodontic treatments is represented in a single graph. 
     
     
         10 . The method as claimed in  claim 6 , wherein the initial time point of the potential orthodontic treatment or treatments is the current time point or an initial time point corresponding to the start of a current orthodontic treatment with an orthodontic appliance worn by the current patient. 
     
     
         11 . The method as claimed in  claim 1 , including an operation of optimizing constraints depending on at least one optimization criterion, an operation in which a succession of steps 3) are implemented by changing one or more of said constraints each time, until an optimal dental situation is found with regard to an optimization criterion, following at least one optimization rule. 
     
     
         12 . The method as claimed in  claim 11  wherein the optimization criterion is chosen from the group made up of a pain coefficient, a cost, a difference from a desired value for a positioning parameter, a duration, a number of orthodontist appointments, a number of aligners, a probability of success, or a combination of these criteria, each criterion being able to be associated with the current orthodontic treatment or a dental situation of said current orthodontic treatment. 
     
     
         13 . Method according to  claim 1 , wherein at step 1) or 2), to acquire said historical data and/or said current data, respectively, the following steps are implemented:
 a) creating a three-dimensional digital reference model of at least one part of an arch of said previous patient and/or said current patient, respectively, or “initial reference model” and, preferably, for each tooth, defining, from the initial reference model, a three-dimensional digital reference model of said tooth, or “tooth model”;   b) acquiring at least one two-dimensional image of the arches of said previous patient and/or said current patient, respectively, called “updated image” under actual acquisition conditions;   c) analysing each updated image and creation, for each updated image, of an updated map relating to discriminant information;   d) optionally, determining, for each updated image, virtual acquisition conditions roughly approximating said actual acquisition conditions;   e) searching, for each updated image, by deformation of the initial reference model, for an updated reference model corresponding to the positioning of the teeth during the acquisition of the updated image, the search being preferably carried out by means of a metaheuristic method, preferably an evolutionary method, preferably by simulated annealing, and   f) collecting data relative to the updated reference model and relative to the orthodontic appliance of said previous patient and/or said current patient, respectively.   
     
     
         14 . Method according to  claim 13  wherein step e) includes the following steps:
 e1) defining a reference model to test as being the initial reference model, then 
 e2) following the next steps, testing virtual acquisition conditions with the reference model to test in order to finely approximate said actual acquisition conditions;
 e21) determining virtual acquisition conditions to test; 
 e22) creating a two-dimensional reference image of the reference model to test under said virtual acquisition conditions to test; 
 e23) processing the reference image to create at least one reference map representing, at least partially, said discriminant information; 
 e24) comparing the updated and reference maps so as to determine a value for a first evaluation function, said value for the first evaluation function depending on the differences between said updated and reference maps and corresponding to a decision to continue or to stop the search for virtual acquisition conditions approximating said actual acquisition conditions with more accuracy than said virtual acquisition conditions to test determined at the last occurrence of step e21); 
 e25) if said value for the first evaluation function corresponds to a decision to continue said search, modifying the virtual acquisition conditions to test, then resuming at step e22); 
 
 e3) determining a value for a second evaluation function, said value for the second evaluation function depending on the differences between the updated and reference maps under the virtual acquisition conditions best approximating said actual acquisition conditions and resulting from the last occurrence of step e2), said value for the second evaluation function corresponding to a decision to continue or to stop the search for a reference model approximating the positioning of the teeth during the acquisition of the updated image with more accuracy than said reference model to test used at the last occurrence of step e2), and if said value for the second evaluation function corresponds to a decision to continue said search, modifying the reference model to test by moving one or more tooth models, then resuming at step e2).