Patent Publication Number: US-2020281699-A1

Title: Dental scanning system

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application Ser. No. 62/813,424, filed Mar. 4, 2019, the entire disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND 
     The subject matter disclosed herein relates to a dental scanning system, and in particular to a dental scanning system that provides visualization and simulation of an outcome of a dental procedure. 
     BRIEF DESCRIPTION 
     According to one aspect of the disclosure a dental scanning system is provided that allows for the registration of scan data of the patient&#39;s face with scan data of the patients teeth. This allows for visualization and simulation of the outcome of a dental procedure. The system may include a device having a paddle with retroreflective targets that is held in the patient&#39;s mouth. The system may further include a helmet with retroreflective targets. The device and paddle is used in combination with a model of the user&#39;s teeth to register scans of the teeth models to the scans of the patient&#39;s face. 
     According to another aspect of the disclosure, a method of providing visualization and simulation of a dental procedure is provided. The method includes in a first instance, scanning a patients face with a three-dimensional (3D) scanning device to generate a first point cloud. A device is inserted in the patients mouth, the device having a tray with an impression material disposed thereon, a paddle is operably coupled to the tray, the paddle having a plurality of targets thereon. In a second instance, the patients face is scanned with the 3D scanning device with the device inserted to generate a second point cloud. In a third instance, a model of the patients teeth is scanned with the 3D scanning device based at least in part on the impression material to generate a third point cloud. The third point cloud is registered to the first point cloud based at least in part on the second point cloud. The registered third point cloud and first point cloud is displayed on a display. 
     In addition to one or more of the features described herein, or as an alternative, further embodiments of the method may include inserting the device onto the model; and in a fourth instance, scanning the model and the device and generating a fourth point cloud; wherein the registering of the third point cloud and first point cloud is further based at least in part on the fourth point cloud. In addition to one or more of the features described herein, or as an alternative, further embodiments of the method may include placing a helmet on the patients head after scanning the patients face with the device inserted, the helmet having at least one member having a plurality of targets; in a fifth instance, scanning the patient and the helmet to generate a fifth point cloud; and wherein the registering of the third point cloud and the first point cloud is based at least in part on the fifth point cloud. 
     In addition to one or more of the features described herein, or as an alternative, further embodiments of the method may include affixing an arm to at least one tooth, the arm having a second paddle with a plurality of targets thereon. In addition to one or more of the features described herein, or as an alternative, further embodiments of the method may include moving the patients jaw; and scanning the patient and the second paddle while the patients jaw is moving to determine the position of the second paddle during movement. In addition to one or more of the features described herein, or as an alternative, further embodiments of the method may include the second paddle is the paddle. 
     In addition to one or more of the features described herein, or as an alternative, further embodiments of the method may include the movement of the jaw is a movement to one or more of directions comprising: a lateral right; a lateral left; a protrusion, a retrusion, a mouth opening, or a free movement. In addition to one or more of the features described herein, or as an alternative, further embodiments of the method may include the registration of the third point cloud to the first point cloud is based at least in part on at least one of a best fit based on natural features and an Iterative Closest Point (ICP) method. 
     In accordance with another embodiment of the disclosure, a system for visualization and simulation of a dental procedure for a patient is provided. The system includes a 3D scanner configured to optically measure coordinates on surfaces to generate a point cloud. A device is provided having a tray and a paddle, the tray having an impression material, the paddle having a plurality of targets thereon. One or more processors are responsive to executable computer instructions for performing a method comprising: in a first instance, scanning the patients face with the 3D scanning device to generate a first point cloud; inserting the device in the patients mouth; in a second instance, scanning the patients face with the device inserted to generate a second point cloud; in a third instance, scanning a model of the patients teeth based at least in part on the impression material to generate a third point cloud; registering the third point cloud to the first point cloud based at least in part on the second point cloud; and displaying the registered third point cloud and first point cloud on a display. 
     In addition to one or more of the features described herein, or as an alternative, further embodiments of the system may include a method that further comprises: in a fourth instance, scanning the model with the device inserted on the model and generating a fourth point cloud; and wherein the registering of the third point cloud and first point cloud is further based at least in part on the fourth point cloud. In addition to one or more of the features described herein, or as an alternative, further embodiments of the system may include a helmet sized to fit on the patients head, the helmet having at least one member with a plurality of targets disposed thereon; wherein the method further comprises: in a fifth instance, scanning the patient and with the helmet disposed on their head to generate a fifth point cloud; and wherein the registering of the third point cloud and the first point cloud is based at least in part on the fifth point cloud. 
     In addition to one or more of the features described herein, or as an alternative, further embodiments of the system may include an arm a first end and a second end, the first end being configured to attach to a tooth of the patient, the second end being attached to a second paddle, the second paddle having a plurality of targets thereon. In addition to one or more of the features described herein, or as an alternative, further embodiments of the system may include a method that further comprises: scanning with the 3D scanner the patient and the second paddle while the patient moves their jaw; and determining the position of the second paddle while the patient moves their jaw. In addition to one or more of the features described herein, or as an alternative, further embodiments of the system may include the movement of the jaw being a movement to one or more directions comprising: a lateral right; a lateral left; a protrusion, a retrusion, a mouth opening, or a free movement. 
     In addition to one or more of the features described herein, or as an alternative, further embodiments of the system may include the registration of the third point cloud to the first point cloud being based at least in part on at least one of a best fit based on natural features and an Iterative Closest Point (ICP) method. 
     In accordance with another embodiment of the disclosure a method of providing visualization and simulation of a dental procedure is provided. The method includes scanning with a noncontact 3D scanner the patients face at rest to generate a first point cloud. The patients face in a smiling position is scanned with the noncontact 3D scanner to generate a second point cloud. A device is inserted in the patients mouth, the device having a tray with a first impression material disposed thereon, the tray being disposed against the patients upper jaw, a paddle is operably coupled to the tray, the paddle having a plurality of targets thereon. The patients face is scanned with the tray disposed on the patients upper jaw to generate a third point cloud. The device is inserted in the patients mount with tray having a second impression material disposed thereon, the tray being disposed against the patients lower jaw. The patients face is scanned with the noncontact 3D scanner with the tray disposed on the patients lower jaw to generate a fourth point cloud. A first physical model of the patients teeth is generated based in part on the first impression material. A second physical model of the patients teeth is generated based in part on the second impression material. The first physical model is scanned with the 3D scanner to generate a fifth point cloud. The second physical model is scanned with the 3D scanner to generate a sixth point cloud. A combination of the first physical model and second physical model are scanned with the 3D scanner to generate a seventh point cloud. The first point cloud and the second point cloud are registered based at least in part on the third point cloud and the fourth point cloud. The fifth point cloud and sixth point cloud are registered based at least in part on the seventh point cloud. The registered first point cloud and the second point cloud are registered with the registered fifth point cloud and sixth point cloud. The registered first point cloud, second point cloud, fifth point cloud and sixth point cloud are displayed on a display. 
     In addition to one or more of the features described herein, or as an alternative, further embodiments of the method may include scanning a combination of the first physical model and second physical model with the tray operably disposed on one of the upper jaw or lower jaw with the 3D scanner to generate an eighth point cloud; and wherein the registration of the registered first point cloud and the second point cloud with the registered fifth point cloud and sixth point cloud is based at least in part on the eighth point cloud. In addition to one or more of the features described herein, or as an alternative, further embodiments of the method may include placing a helmet on the patients head after scanning the patients face with the device inserted, the helmet having at least one member having a plurality of targets; scanning the patient and the helmet to generate a ninth point cloud; and wherein the registration of the registered first point cloud and the second point cloud with the registered fifth point cloud and sixth point cloud is further based at least in part on the ninth point cloud. 
     These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The subject matter, which is regarded as the disclosure, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a flow diagram for operating a dental scanning system in accordance with an embodiment; 
         FIG. 2  is an image of a patient having her face three-dimensionally scanned in a resting face position; 
         FIG. 3  is an image of the three-dimensional scan of the patient&#39;s face; 
         FIG. 4  is an image of a patient having her face three-dimensionally scanned in a smiling face position; 
         FIGS. 5-9  are images of the patient being scanned with a fork and paddle coupled to her mouth; 
         FIG. 10  is an image of the patient with the helmet and paddle installed; 
         FIG. 11  is an image of a patient with the paddle coupled to their lower jaw; 
         FIG. 12  is an image of the patient having her face three-dimensionally scanned with the helmet on and the paddle in her mouth; 
         FIGS. 13-16  are images of the patient moving her mouth while three-dimensionally scanning her face; 
         FIGS. 18-20  are images of computer software for identifying the patients teeth; 
         FIG. 21  is an image of a model of the patient&#39;s lower jaw and teeth being three-dimensionally scanned. 
         FIG. 22  is an image of a model of the patients lower jaw and teeth and upper jaw and teeth being three-dimensionally scanned; 
         FIG. 23  is an image of a model of the patients upper jaw and teeth being three-dimensionally scanned; 
         FIGS. 24-26  are images of the patients upper jaw and teeth with the paddle and fork disposed thereon being three-dimensionally scanned; 
         FIGS. 27-31  are images of the three-dimensional scans performed in  FIGS. 21-26 ; 
         FIG. 32  and  FIG. 33  are images of the three-dimensional scans of  FIGS. 27-31  being registered and aligned into the same coordinate frame of reference; 
         FIG. 34  is an image of the three-dimensional scan of the user&#39;s face acquired if  FIG. 12 ; 
         FIG. 35  is an image of the three-dimensional scan of the user&#39;s face acquired in  FIG. 3 ; 
         FIG. 36  is an image of the three-dimensional scan of the user&#39;s face acquired in  FIG. 2 ; and 
         FIG. 37  is a flow diagram in accordance with an embodiment. 
     
    
    
     The detailed description explains embodiments of the disclosure, together with advantages and features, by way of example with reference to the drawings. 
     DETAILED DESCRIPTION 
     Embodiments of the present disclosure provide advantages in allowing the three-dimensional scanning of a patients face and teeth and the generation of a computer image of the three-dimensional scan. Embodiments of the present disclosure provide advantages in allowing a patient to see a simulated result of a proposed dental procedure. Further embodiments of the present disclosure provide advantages in being able to three-dimensionally measure the movement of the patient&#39;s mouth to allow the visual appearance of a dental procedure to be simulated prior to the procedure being performed. 
     Referring to  FIG. 1 , a method  100  is shown for scanning a patient&#39;s face and teeth to provide a visualization of a proposed dental procedure. The method starts in box  102  where the patients  104  face is scanned with a three-dimensional scanning device  106  ( FIG. 2-4 ), such as a noncontact optical measuring device. Noncontact optical measuring devices may include a triangulation laser scanner such as a scanning device manufactured by FARO Technologies, Inc., of Lake Mary, Fla., USA for example. It should be appreciated that other types of scanning devices, such as but not limited to a time of flight scanner, a structured light scanner, or a phase-based scanner may also be used. In general, a triangulation scanner has a projector  108  that projects a light pattern (i.e. infrared light pattern) on to the person or object being scanned. Images of the light pattern are acquired using a pair of cameras  110 . A third camera  112 , such as a color camera for example, acquires texture or color information of the person or object. Other types of scanning devices include, but are not limited to laser line scanners, line scanners, flying-dot scanners, and laser line probes. 
     In an embodiment, a first scan of the patient&#39;s face may be scanned with the patient&#39;s face in a rest position ( FIG. 2 ). A second scan of the patient&#39;s face is performed with the patient&#39;s face in a smiling position ( FIG. 4 ). 
     The method  100  then proceeds to block  114  where a device  116  is inserted into the patient&#39;s mouth ( FIG. 5 ). In an embodiment, the device includes a tray or body  118  having an impression material, such as silicone material  120  for example, disposed thereon. In an embodiment, the device  116  includes silicone material  120  on both sides of the body  118 . The body  118  includes an arm  122  extending from one side. The device  118  is placed in the patient&#39;s  104  mouth and their teeth are closed over the device  116  and embedded in the silicone material  120 . The arm  122  extends out of the patient&#39;s mouth. It should be appreciated that the silicone material  120  allows the body  118  to be securely held in the patient&#39;s mouth. 
     Either prior to insertion of the device  116  (e.g. a fork device) into the patient&#39;s mouth or subsequent to insertion, a paddle member  124  ( FIGS. 6-9 ) is coupled to the arm  122 . In an embodiment, the paddle  124  includes a plurality of targets, such as reflective dots  126 . As will be discussed in more detail herein, in an embodiment the dots  126  allow the three-dimensional measurement of position of the paddle with six degrees of freedom when measured by the scanner  106 . In an embodiment, the paddle  124  has a plurality (e.g. four) semi-spherical protrusions extending from a surface facing away from the patient&#39;s face. In an embodiment, the semi-spherical protrusions are different sizes. 
     With the device  116  and the paddle  124  held in the patient&#39;s mouth, the scanning device  106  is used to measure the front of the patient&#39;s face. In an embodiment, an optional infrared illuminator  128  is coupled to the top of the scanning device  106 . 
     The method  100  then proceeds to block  130  where a helmet device  132  is placed on the patient&#39;s head ( FIG. 10 ). The helmet  132  includes an arm  134  that wraps around the top of the patient&#39;s head. Extending from the arm  134  is a pair of members  136 ,  138  that extend on either side of the patient&#39;s nose. Each member  136 ,  138  includes a plurality of targets, such as a plurality of reflective dots  140  for example. The patient&#39;s face, with the helmet  132  on their head and the paddle  124  held by the device  116  in the patient&#39;s mouth, another three-dimensional scan of the patient&#39;s face is performed using the scanner  106 . 
     In one embodiment, the device  116  is then removed and the paddle  124  is connected to a tooth  142  ( FIG. 11 ). It should be appreciated that when the paddle  124 , when it is attached to the lower tooth or jaw is measured by the scanner  106  ( FIG. 12 ), it may be registered to the earlier performed scans by its position the helmet  132 . In one embodiment, it may be desired to measure the movement of the patient&#39;s jaw. This may provide advantages in simulating how a particular dental procedure will be impacted when the lower jaw is in different positions. In an embodiment, the measurement of the movement of the users jaw also helps determine where the user&#39;s jaw pivots. 
     As shown in  FIGS. 13-16 , the patient moves their jaw in predetermined directions as indicated by the arrows. As the patient moves their jaw, the scanner  106  is used to measure the position(s) of the paddle  124 . For example, lateral right; lateral left; protrusion, retrusion, mouth opening, free movement (optional). 
     When the scanning with the scanner  106  is completed, the measurements, sometimes referred to a point cloud, for each of the scans is saved to memory. The method  100  then proceeds to block  144  where an impression is made of the patients upper teeth and lower teeth ( FIG. 17 ) in a manner as is known in the art. A model is made of the upper teeth  146  and the lower teeth  148  as is known in the art, such as by using plaster for example. 
     The models  146 ,  148  are then scanned with a three-dimensional scanner  150  in block  152 . The scanner  150  may be a triangulation type optical scanner that includes a bed or platen  154  that may be moved or rotated in a prescribed manner to three-dimensionally measure the models  146 ,  148 . In an embodiment, first the model  148  of the lower teeth are measured with the scanner  150  ( FIG. 21 ). Then the model  146  of upper teeth are placed on the model of the lower teeth  148  and another scan is performed ( FIG. 22 ). Then a third scan of the model  146  of the upper teeth is performed ( FIG. 23 ). 
     With the model  146  of the upper teeth on the platen  154 , the device  116  with the paddle  124  attached is placed on the model  146  of the upper teeth. A fourth scan is performed with the scanner  150  ( FIGS. 24-26 ). It should be appreciated that the scanning of the device  116  with the impressions from the patients teeth from the original scan ( FIG. 5 ) still formed therein allows the paddle  124  to have the substantially the same relative position to the model  146  of the upper teeth as it did to the upper teeth of the patient during the scan of  FIG. 5 . 
     With the scans performed, the method  100  then proceeds to block  154  where the scans or point clouds of the models  146 ,  148  and the model  146  with the device  116 /paddle  124  are registered together ( FIGS. 27-33 ). In an embodiment, the registration is a best fit based on natural features of the scan data. In another embodiment, the scans may be registered together using an Iterative Closest Point (ICP) methodology. 
     With the scans of the models  146 ,  148  and the model  146  with the device  116 /paddle  124  are registered together, the method  100  proceeds to block  156 . In an embodiment, the scans of the patients face from  FIG. 2 ,  FIG. 4 , and  FIG. 10  are registered together using a best fit or ICP methodology as shown in  FIGS. 34-36 . Since the scan data from  FIG. 10  includes the paddle  124 , the scans of the models  146 ,  148  and the model  146  with the device  116 /paddle  124  may then be registered to the scans of the patient&#39;s face. Thus the scan data of the models of the patient&#39;s upper and lower teeth  146 ,  148  may be “placed” in the scan data of the of the user&#39;s face. 
     In an embodiment, the method  100  may proceed to block the registered scan data (patient&#39;s face, models  146 ,  148 ) may be exported to a dental CAD system in block  158 , such as ExoCAD for example. In an embodiment, the movement data from  FIGS. 13-16  may be included in the data export to allow the movement of the jaw to be simulated. It should be appreciated that the CAD system may be then used to simulate, design, display, and visualize a dental procedure and the patient may be shown the how the procedure will look when completed. 
     Another method  200  of scanning a patient for a dental procedure is shown in  FIG. 37 . This method includes scanning a patients face at rest (e.g. mouth closed in a natural or relaxed position) in box  202  to generate a first point cloud. The method then proceeds to block  204  where the patients face is scanned in a “smiling” position to generate a second point cloud. As used herein a smiling position is where the patient forms their features into a pleased, kind, or amused expression, typically with the corners of the mouth turned up and the front teeth exposed. The method  200  then proceeds to block  206  where the tray  118  is placed in the patients mouth against the upper teeth to form an impression in the impression material  120 . The paddle  124  is attached to the tray  118  (such as via arm  122 ) in block  208 . 
     With the paddle  124  in place, the patients face and the paddle  124  are scanned with the 3D scanner to generate a third point cloud. With the tray  118  still in the patients mouth and the paddle  124  positioned in front of the patients mouth, the helmet  132  is placed on the patients head in block  212 . The method  200  then proceeds to block  214  where a scan is performed with the 3D scanner of the patients face, the helmet  132  and the paddle  124  to generate a fourth point cloud in block  214 . 
     The method  200  then proceeds to block  216  where the paddle  124  is mounted to the patients lower jaw, such as by attaching the end of the arm  123  ( FIG. 11 ) to the patients tooth  142 . The method  200  then proceeds to block  218  where a 3D scan is performed with the 3D scanner of the paddle  124  as the patients jaw is moved from a first position to a second position. In an embodiment, the 3D scanner tracks the position of the targets  126  as the jaw is moved. In an embodiment, the position of the targets  126  is determined on a periodic basis (e.g. 60 frames per second) or on an aperiodic basis. In an embodiment, the movement in block  218  may be performed multiple times with the jaw being moved in a different direction each time. In an embodiment, the movement may be a lateral right; a lateral left; a protrusion, a retrusion, a mouth opening, or a free movement. 
     The method  200  then moves to block  220  where a physical model  146 ,  148  is made of the patients upper teeth and lower teeth. The model may be made for example, by casting a material into the impression material in tray  118 . With the models made, a replica of the patients teeth was created ( FIG. 21-23 ). The method  200  then proceeds to block  222 . In this step, the 3D scanner is used to scan the lower jaw, the upper jaw, and the combination of the upper jaw and lower jaw, with a point cloud being generated for each. In an embodiment, the tray  118  with the paddle  124  attached is placed between the lower jaw and the upper jaw and an additional scan is performed with the 3D scanner to generate a point cloud. 
     The method  200  then proceeds to block  224  where the point clouds generated in block  222  are registered together. The method  200  then proceeds to block  226  where the point clouds of the patients face from block  202  and block  204  are registered together. The method  200  then proceeds to block  228  where the registered model point clouds (from block  224 ) are registered with the patient face point cloud (from block  226 ). The method  200  then proceeds to block  230  where the the registered scan data (patient&#39;s face and models) may be exported to a dental CAD system, such as ExoCAD for example. In an embodiment, the movement data from may be included in the data export to allow the movement of the jaw to be simulated. It should be appreciated that the CAD system may be then used to simulate, design, display, and visualize a dental procedure and the patient may be shown the how the procedure will look when completed. 
     It should be appreciated that while embodiments herein may refer to a single 3D scanning device, this is for example purposes and the claims should not be so limited. In some embodiments, multiple 3D scanning devices may be used, for example a first 3D scanning device (e.g. an area or structured light scanner) may be used to scan the patient, the a second 3D scanning device (e.g. a line scanner or laser line probe) may be used to scan the models of the patients teeth. It is contemplated that multiple 3D scanning technologies may be used cooperatively to measure the patient and the models. 
     The term “about” is intended to include the degree of error associated with measurement of the particular quantity based upon the equipment available at the time of filing the application. For example, “about” can include a range of ±8% or 5%, or 2% of a given value. 
     Additionally, the term “exemplary” is used herein to mean “serving as an example, instance or illustration.” Any embodiment or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or designs. The terms “at least one” and “one or more” are understood to include any integer number greater than or equal to one, i.e. one, two, three, four, etc. The terms “a plurality” are understood to include any integer number greater than or equal to two, i.e. two, three, four, five, etc. The term “connection” can include an indirect “connection” and a direct “connection.” It should also be noted that the terms “first”, “second”, “third”, “upper”, “lower”, and the like may be used herein to modify various elements. These modifiers do not imply a spatial, sequential, or hierarchical order to the modified elements unless specifically stated. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof. 
     While the disclosure is provided in detail in connection with only a limited number of embodiments, it should be readily understood that the disclosure is not limited to such disclosed embodiments. Rather, the disclosure can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the disclosure. Additionally, while various embodiments of the disclosure have been described, it is to be understood that the exemplary embodiment(s) may include only some of the described exemplary aspects. Accordingly, the disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.