System, device and method for dental intraoral scanning

Abstract

There is provided according to some embodiments, a system, device and method for a three dimensional (3D) intraoral scanning of at least a portion of a tooth. An intraoral scanner may include a shadow casting object extending between a light emitter and the portion of the tooth. An imaging module may image the portion of the tooth and/or the projected shadow of the shadow casting object. A method to construct a 3D model may include illuminating at least a portion of the tooth with a light emitter; casting a shadow on the portion of the tooth by an object located between the emitter and the tooth; imaging the portion of the tooth, including at least a part of the shadow; and determining a location of a point on the tooth and related to the shadow, using the image.

1 .- 31 . (canceled) 
     
     
         32 . A three dimensional (3D) intraoral scanner system for imaging at least a portion of a tooth in an oral cavity comprising:
 an intraoral portion sized and shaped for insertion into the oral cavity, said intraoral portion including:   a light emitter for emitting a light;   a shadow casting object; at least a portion of said shadow casting object in a field of illumination of said light source and extending away from a housing of said intraoral portion; an imager positioned to image at least an edge of a shadow cast by said shadow casting object in said light reflected off a portion of a tooth located at a distance of between 3 mm and 5 cm from said imager.   
     
     
         33 . The intraoral scanner system of  claim 32  further comprising:
 a processor configured to process an image of said light received by said imager to provide location information. 
 
     
     
         34 . The system of  claim 33 , wherein said processor is configured to process said image to determine a location of a portion at an edge of said shadow. 
     
     
         35 . The intraoral scanner system of  claim 33  wherein said processer is configured to process said image to determine a shape of said tooth. 
     
     
         36 . The system of  claim 33 , wherein said processor is further configured to:
 establish a position of imager with respect to a reference feature in the oral cavity.   
     
     
         37 . The system of  claim 36 , wherein said processor is configured for said establishing said position of said imager from said image. 
     
     
         38 . The system of  claim 32 , wherein said imager is located at a known orientation to said light emitter. 
     
     
         39 . The system of  claim 33 , wherein said processor is further configured to:
 establish a position of said shadow casting object; and   establish a relative location of said imager with respect to said light emitter and a portion of said shadow casting object.   
     
     
         40 . The system of any of  claim 32 , wherein a portion of said shadow casting object casting said edge of said shadow has a known fixed orientation to said light emitter. 
     
     
         41 . The system of  claim 33 , wherein said processor is further configured to:
 establish a relative location with respect to said light emitter of a portion of said shadow casting object casting said edge of said shadow.   
     
     
         42 . The system of  claim 32 , wherein said at least a portion of said shadow casting object, said light emitter and said imager are collocated such that they do not fall within 0.5 mm of a single plane. 
     
     
         43 . The system of  claim 33 , wherein said at least a portion of said shadow casting object is within a field of view of said imager and wherein said processor is further configured to determine a position of said shadow casting object from said image. 
     
     
         44 . The system of  claim 32 , wherein said light emitter comprises a plurality of light sources, not all illuminated at a same time. 
     
     
         45 . The system of  claim 33 , wherein said processor is configured to process a plurality of images to designate at least one reference feature in said plurality of images and calculate said location of at least one point related to said shadow with respect to said reference feature. 
     
     
         46 . The system of  claim 33 , wherein said processor is configured to designate a features which appear in at least  2  of a plurality of images and calculate the movement of said imager relative of said feature. 
     
     
         47 . The system of  claim 46 , wherein said processor is further configured to combine location information determined at different imager locations to a single 3D model. 
     
     
         48 . A system for imaging a tooth in an oral cavity comprising:
 a light emitter sized and shaped to fit in an oral cavity;   an imager sized and shaped to fit in said oral cavity simultaneously with the light emitter and directed to collect light from the light emitter reflected off the tooth at a point of an edge of a shadow on said tooth; a processor configured to receive an image from said imager and process said image to determine a location of said point and a shape of said tooth.   
     
     
         49 . The system of  claim 48 , wherein said processor is further configured to:
 establish a position of said imager with respect to a reference feature in the oral cavity from said image.   
     
     
         50 . The system of  claim 49 , wherein said shadow has at least two edges cast by opposite exterior sides of the shadow casting object. 
     
     
         51 . The system of  claim 48 , wherein said processor is further configured to:
 establishing a position of said object producing the shadow from said image.   
     
     
         52 . The system of  claim 33 , wherein said light emitter comprises a plurality of light emitter elements and wherein said processor is configured to track said shadow casting object and to select one or more of said light emitter elements based on the location of the shadow casting object to cast a shadow on the tooth. 
     
     
         53 . The system of  claim 48 , wherein said imager comprises two separate and spaced apart imager elements aimed at said point. 
     
     
         54 . The system of  claim 53 , wherein said processor is configured to determine a location of said point based on a difference between images acquired by different imager elements.