Occlusal wear evaluation apparatus and occlusal wear evaluation method

Abstract

An occlusal wear evaluation apparatus capable of evaluating quantitatively an occlusal wear of a used denture reads three dimensional data of a denture before use and three dimensional data of the denture after use, calculates a difference in a set value of an articulator allowing the maxillary dental arch and the mandibular dental arch of the denture to occlude between the denture before use and the denture after use, by way of simulating movements of a jaw in the articulator with the three dimensional data of the denture before use and the three dimensional data of the denture after use, and indicates the calculated difference.

1 . An occlusal wear evaluation apparatus comprising an input device, an arithmetic device and a display device, wherein
 the input device is configured to input three dimensional data of a denture before use and three dimensional data of the denture after use into the arithmetic device,   the arithmetic device is configured to calculate a set value of an articulator allowing the maxillary dental arch and the mandibular dental arch of the denture to occlude for each of the denture before use and the denture after use by way of simulating movements of a jaw in the articulator with the three dimensional data of the denture before use and the three dimensional data of the denture after use, to calculate a difference in the set value between the denture before use and the denture after use, the set value including at least one of a distance between condyle paths, a distance between a maxillary dental arch and a mandibular dental arch, an inclination of a sagittal condylar path, an angle of a balancing side lateral condylar path, an amount of an immediate side shift, an angle of a working side lateral condylar path, an inclination of sagittal incisal path, and a guidance angle of a lateral incisal path, and   the display device is configured to indicate the difference in the set value calculated by the arithmetic device.   
     
     
         2 . The occlusal wear evaluation apparatus according to  claim 1 , wherein the arithmetic device is configured to calculate a relative angle between the maxillary dental arch and the mandibular dental arch of the denture in a centric occlusal position, and the display device is configured to indicate the relative angle calculated by the arithmetic device. 
     
     
         3 . The occlusal wear evaluation apparatus according to  claim 1 , wherein the arithmetic device is configured to calculate a relative position between the maxillary dental arch and the mandibular dental arch of the denture in a centric occlusal position, and the display device is configured to indicate the relative position calculated by the arithmetic device. 
     
     
         4 . The occlusal wear evaluation apparatus according to  claim 1 , wherein the arithmetic device is configured to calculate at least one of a relative moving distance and a relative moving angle of a sliding movement of the maxillary teeth and the mandibular teeth of the denture from a first occlusal condition to a second occlusal condition, and the display device is configured to indicate at least one of the relative moving distance and the relative moving angle calculated by the arithmetic device. 
     
     
         5 . The occlusal wear evaluation apparatus according to  claim 1 , wherein the arithmetic device is configured to calculate a volume of the denture, and the display device is configured to indicate the volume calculated by the arithmetic device. 
     
     
         6 . The occlusal wear evaluation apparatus according to  claim 1 , wherein the arithmetic device is further configured to calculate a height of a cusp of the denture, and the display device is configured to indicate the height of the cusp calculated by the arithmetic device. 
     
     
         7 . The occlusal wear evaluation apparatus according to  claim 1 , wherein the arithmetic device is further configured to calculate an angular difference of planes which represent a certain area of the denture, and the display device is configured to indicate the angular difference calculated by the arithmetic device. 
     
     
         8 . An occlusal wear evaluation apparatus comprising an input device, an arithmetic device and a display device, wherein
 the input device is configured to input three dimensional data of a plurality of dentures used by a same patient into the arithmetic device,   the arithmetic device is configured to calculate a set value of an articulator allowing the maxillary dental arch and the mandibular dental arch of the denture to occlude for the each denture, by way of simulating movements of a jaw in the articulator with the three dimensional data of the dentures, the set value including at least one of a distance between condyle paths, a distance between maxillary dental arch and a mandibular dental arch, an inclination of a sagittal condylar path, an angle of a balancing side lateral condylar path, an amount of an immediate side shift, an angle of a working side lateral condylar path, an inclination of a sagittal incisal path and a guidance angle of a lateral incisal path, and   the display device is configured to indicate the set values calculated by the arithmetic device in a time series chart.   
     
     
         9 . The occlusal wear evaluation apparatus according to  claim 1 , wherein the arithmetic device is configured to calculate a relative angle between the maxillary dental arch and the mandibular dental arch of the denture in a centric occlusal position, and the display device is configured to indicate the relative angle calculated by the arithmetic device. 
     
     
         10 . The occlusal wear evaluation apparatus according to  claim 8 , wherein the arithmetic device is configured to calculate a relative position between the maxillary dental arch and the mandibular dental arch of the denture in a centric occlusal position, and the display device is configured to indicate the relative position calculated by the arithmetic device. 
     
     
         11 . The occlusal wear evaluation apparatus according to  claim 8 , wherein the arithmetic device is configured to calculate at least one of a relative moving distance and a relative moving angle of a sliding movement of the maxillary teeth and the mandibular teeth of the denture from a first occlusal condition to a second occlusal condition, and the display device is configured to indicate at least one of the relative moving distance and the relative moving angle calculated by the arithmetic device. 
     
     
         12 . The occlusal wear evaluation apparatus according to  claim 8 , wherein the arithmetic device is configured to calculate a volume of the denture, and the display device is configured to indicate the volume calculated by the arithmetic device. 
     
     
         13 . The occlusal wear evaluation apparatus according to  claim 8 , wherein the arithmetic device is further configured to calculate a height of a cusp of the denture, and the display device is configured to indicate the height of the cusp calculated by the arithmetic device. 
     
     
         14 . The occlusal wear evaluation apparatus according to  claim 8 , wherein the arithmetic device is further configured to calculate an angular difference of planes which represent a certain area of the denture, and the display device is configured to indicate the angular difference calculated by the arithmetic device. 
     
     
         15 . An occlusal wear evaluation method comprising
 inputing three dimensional data of a denture before use and three dimensional data of the denture after use into a computer,   calculating a set value of an articulator allowing a maxillary dental arch and a mandibular dental arch of the denture to occlude for each of the denture before use and the denture after use by way of simulating movements of a jaw in the articulator with the three dimensional data of the denture before use and the three dimensional data of the denture after use on the computer, to calculate a difference in the set value between the denture before use and the denture after use, the set value including at least one of a distance between condyle paths, a distance between a maxillary dental arch and a mandibular dental arch, an inclination of a sagittal condylar path, an angle of a balancing side lateral condylar path, an amount of an immediate side shift, an angle of a working side lateral condylar path, an inclination of sagittal incisal path, and a guidance angle of a lateral incisal path, and   indicating the calculated deference on a screen.   
     
     
         16 . An occlusal wear evaluation method comprising
 inputing three dimensional data of a plurality of denture used by a same patient into a computer,   calculating a set value of an articulator allowing the maxillary dental arch and the mandibular dental arch of the denture to occlude for the each denture by way of simulating movements of a jaw in the articulator with the three dimensional data of the dentures on the computer, the set value including at least one of a distance between condyle paths, a distance between maxillary dental arch and a mandibular dental arch, an inclination of a sagittal condylar path, an angle of a balancing side lateral condylar path, an amount of an immediate side shift, an angle of a working side lateral condylar path, an inclination of a sagittal incisal path and a guidance angle of a lateral incisal path, and   indicating the calculated set values in a time series chart on a screen.