Patent Publication Number: US-2023139151-A1

Title: System and method for fabricating a dental restoration

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/266,242, filed Feb. 4, 2019, entitled SYSTEM AND METHOD FOR FABRICATING A DENTAL RESTORATION, which is a continuation of U.S. patent application Ser. No. 15/838,873, filed on Dec. 12, 2017, entitled SYSTEM AND METHOD FOR FABRICATING A DENTAL RESTORATION, which is a continuation of U.S. patent application Ser. No. 14/695,353, filed on Apr. 24, 2015, now U.S. Pat. No. 9,861,458, entitled SYSTEM AND METHOD FOR FABRICATING A DENTAL RESTORATION, which claims priority to U.S. Provisional Patent Application No. 61/983,888 filed on Apr. 24, 2014, entitled SYSTEM AND METHOD FOR FABRICATING A DENTAL RESTORATION, the disclosures of which are hereby incorporated by reference in their entireties. 
    
    
     BACKGROUND 
     Teeth are typically classified as anterior or posterior. Anterior teeth are in the front of the mouth; posterior teeth are in the back of the mouth. Typically, a patient has six upper anterior teeth and six lower anterior teeth. The anterior teeth usually have a narrow incisal edge. In a patient who has a normal bite relationship, the incisal edges of the upper anterior teeth are positioned slightly further towards the front of the patient&#39;s mouth than the incisal edges of the lower anterior teeth. In this arrangement, the incisal edge of the lower anterior teeth may contact the rear-facing (or lingual) surface of the upper anterior teeth. 
     A patient can have as many as ten upper posterior teeth and ten lower posterior teeth, although it is quite common to have fewer (e.g., wisdom teeth are frequently removed). The posterior teeth have an occlusal surface that faces the teeth on the opposite arch and forms the biting surface. 
     A dental restoration is used to restore a tooth or multiple teeth. For example, a crown is a dental restoration that is used to restore a single tooth. A bridge is another example of a dental restoration. A bridge restores multiple teeth. In some circumstances, dental restorations are used to restore functionality after a tooth is damaged. In other circumstances, dental restorations are used to aesthetically improve a patient&#39;s dentition. 
     Generally, a dental restoration must fit harmoniously with the patient&#39;s surrounding dentition, and especially with the opposing dentition. For example, the occlusal surface (i.e., the biting surface) of a restoration should be carefully designed to avoid interfering with the closure and movement of the jaw. 
     SUMMARY 
     In general terms, this disclosure is directed to a system and method for simulating occlusal interference using a functional bite map. In one possible configuration and by non-limiting example, a dental restoration is compared to an interference surface generated from a functional bite map to identify occlusal interference regions. 
     One aspect is a system for fabricating a dental restoration to restore a tooth at a restoration site in a dentition of a patient, wherein the dentition includes a restoration dental arch and an opposing dental arch, the restoration dental arch including the restoration site and the opposing dental arch being opposite the restoration dental arch, comprising: an impression apparatus configured to capture an impression of the dentition of the patient, the portion of the dentition including the restoration site; a motion capture apparatus configured to capture a plurality of location data points, the location data points representing the locations of the opposing dental arch relative to the restoration dental arch as the dentition moves between a plurality of bite positions; an interference model generation system configured to generate an interference model for the restoration site, wherein the interference model includes an interference surface, the interference surface corresponding to the locations of a portion of the opposing dental arch in at least a portion of the plurality of the locations represented by the plurality of location data points; and a restoration design system for designing a restoration using the interference model. 
     Another aspect is a method of generating a dental restoration for a patient, comprising: generating an interference model from an impression and a functional bite map, the impression representing at least a portion of a dentition of the patient, the functional bite map representing bite registration information for a plurality of positions of the dentition of the patient; aligning the interference model to a restoration site of the patient; and designing a dental restoration for the restoration site using the interference model. 
     Yet another aspect is a method of generating a dental restoration to restore an anterior tooth of a patient, comprising: generating an incisal guide path, using a computing device, corresponding to the lingual surface of the anterior tooth; fabricating an incisal guide path structure based on the incisal guide path; and using the incisal guide path structure to generate the dental restoration. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic block diagram illustrating an example of a system for simulating occlusal interference using a functional bite map. 
         FIG.  2    illustrates an example architecture of a computing device, which can be used to implement aspects according to the present disclosure. 
         FIG.  3    is a flow chart illustrating an example method of capturing a dental impression using embodiments of the system of  FIG.  1   . 
         FIG.  4    is an example process performed at some embodiments of the motion capture station  106  of  FIG.  1   . 
         FIG.  5    is an example embodiment of a bite capture apparatus for capturing the functional bite map of  FIG.  1   . 
         FIG.  6    is an illustration of an embodiment of the bite capture apparatus of  FIG.  5    being used to capture bite motion information of a patient. 
         FIG.  7    is an illustration of an embodiment of the bite capture apparatus of  FIG.  5    after the securing layer has formed to the patient&#39;s dentition. 
         FIG.  8    is an illustration of an embodiment of the bite capture apparatus of  FIG.  5    after the motion capture layer has captured the relative motion from the patient&#39;s dentition. 
         FIG.  9    is another example embodiment of a bite capture apparatus for capturing the functional bite map of  FIG.  1   . 
         FIG.  10    is an illustration of the bite capture apparatus of  FIG.  9    after the motion capture structure has captured the relative motion from the opposing dentition of the patient. 
         FIG.  11    illustrates an exemplary architecture of the program modules and program data of the design system of  FIG.  1   . 
         FIG.  12    is a flow chart illustrating an example method of fabricating the dental restoration using the interference model data of  FIG.  1   . 
         FIG.  13    is a flow chart illustrating an example method of fabricating the interference model using the interference model data of  FIG.  1   . 
         FIG.  14    is a cross-section illustration of an example interference model of  FIG.  1   , including an interference surface. 
         FIG.  15    is a schematic diagram of an embodiment of the interference model of  FIG.  1   . 
         FIG.  16    is an illustration of an example embodiment of the interference model of  FIG.  1    joined with a dental model. 
         FIG.  17    is an illustration of another example embodiment of the interference model of  FIG.  1    joined with a dental model. 
         FIG.  18    is an illustration of the dental model of  FIG.  16    with the bite capture apparatus of  FIG.  9   . 
         FIG.  19    is a flow chart illustrating an example method of fabricating the dental restoration using the interference model of  FIG.  1   . 
         FIG.  20    is a flow chart illustrating an example method of designing the dental restoration data using the interference model data of  FIG.  1   . 
         FIG.  21    is an illustration of a cross-sectional view of the interference model data and the dental restoration data of  FIG.  1   . 
         FIG.  22    is an illustration of a cross-sectional view of the dental restoration data of  FIG.  1    with an example embodiment of a color map on the exterior surface. 
         FIG.  23    is a schematic block diagram illustrating an example of a system for simulating incisal guide paths to fabricate a provisional restoration. 
         FIG.  24    illustrates an exemplary architecture of the program modules and the program data of the provisional design system of  FIG.  23   . 
         FIG.  25    is a flow chart illustrating an example method of using the system of  FIG.  23    to fabricate and install the provisional restoration. 
         FIG.  26    is a flow chart illustrating another example method of using the system of  FIG.  23    to fabricate and install the provisional restoration. 
         FIG.  27    is a flow chart illustrating an example method of using the system of  FIG.  23    to fabricate a dental restoration based on the provisional restoration. 
         FIG.  28    is a cross-sectional illustration of the anterior dentition of the patient. 
         FIG.  29    is an illustration of an example of an embodiment of the provisional restoration mold of  FIG.  23   . 
         FIG.  30    is an illustration of an alternative embodiment of the provisional restoration mold of  FIG.  23   . 
         FIG.  31    is a cross-sectional illustration of a provisional restoration mold of  FIG.  23    being used to form a provisional restoration on a restoration site R. 
         FIG.  32    is a cross-sectional illustration of an articulator being used with an incisal guide model of  FIG.  23   . 
     
    
    
     DETAILED DESCRIPTION 
     Various embodiments will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the appended claims. 
     The present disclosure relates to a system for fabricating dental restorations. The dental restoration is configured to temporarily or permanently replace part or all of one or more of a patient&#39;s teeth. In some embodiments, the dental restorations are fabricated to avoid interfering with the opposing dentition. In some embodiments, relative motion data is used to construct an interference model representative of the position of the opposing dentition in multiple bite locations. In some embodiments, a mold is fabricated based on an incisal guide plane. In some embodiments, the mold is used to fabricate the restoration. In some embodiments, the incisal guide plane is generated from motion data. In other embodiments, the incisal guide plane is generated from an impression of the dentition of a patient. 
       FIG.  1    is a schematic block diagram illustrating an example of a system  100  for simulating occlusal interference using a functional bite map to fabricate a dental restoration  134 . In this example, the system  100  includes a dental office  102  and a dental lab  114 . 
     The example dental office  102  includes a dental impression station  104 , a motion capture station  106 , and a restoration installation station  136 . Although shown as a single dental office in this figure, in some embodiments, the dental office  102  comprises multiple dental offices. For example, in some embodiments, one or both of the dental impression station  104  and the motion capture station  106  are in a different dental office than the restoration installation station  136 . Further, in some embodiments, one or more of the dental impression station  104 , the motion capture station  106 , and the restoration installation station  136  are not in a dental office. 
     The example dental impression station  104  generates a dental impression  108  of the dentition of the patient P. The dental impression  108  is a geometric representation of the dentition of the patient P. In some embodiments, the dental impression  108  is a physical impression captured using an impression material, such as sodium alginate, or vinyl polysiloxane. In other embodiments, other impression materials are used as well. 
     In some embodiments, the dental impression  108  is a digital impression. In some embodiments, the digital impression is represented by one or more of a point cloud, a polygonal mesh, a parametric model, or voxel data. In some embodiments, the digital impression is generated directly from the dentition of the patient P, using for example an intraoral scanner. Example intraoral scanners include the TRIOS Intra Oral Digital Scanner, the Lava Chairside Oral Scanner C.O.S., the Cadent iTero, the Cerec AC, the Cyrtina IntraOral Scanner, and the Lythos Digital Impression System from Ormco. In other embodiments, a digital impression is captured using other imaging technologies, such as computed tomography (CT) or magnetic resonance imaging (MRI). In yet other embodiments, the digital impression is generated from a physical impression by scanning the impression or plaster model of the dentition of the patient P created from the physical impression. Examples of technologies for scanning a physical impression or model include three dimensional laser scanners and computed tomography (CT) scanners. In yet other embodiments, digital impressions are created using other technologies. 
     The motion capture station  106  captures a representation of the movement of the dental arches relative to each other. In some embodiments, the motion capture station generates at least one of a functional bite map  110  and motion data  112 . 
     In some embodiments, the functional bite map  110  is a physical apparatus containing indentations that form a path that corresponds to the movement of the dental arches of the patient relative to each other. For example, in some embodiments, the functional bite map  110  is formed in one or more sheets of a bite registration material. In some embodiments, the patient P bites into the bite registration material. In some embodiments, after the patient P bites into the bite registration material, the patient P is instructed to move between various bite positions, such as such as centric, excursive, left lateral, and right lateral. In other embodiments, the functional bite map  110  is formed from multiple sheets of bite registration material that are each captured in a different bite position. In some embodiments, the bite registration material is formed from wax, alginate, vinyl polysiloxane, or combinations thereof. In some embodiments, the bite registration material is formed from wax infused with a powdered metal, such as aluminum or copper. Some example bite registration materials include THEMACRYL® thermoplastic material from Airway Technologies, LLC of Carrollton, Tex.; vinyl polysiloxane putty such as FLEXITIME® impression material from Heraeus Kulzer of South Bend, Ind.; FUTAR® D bite registration material from Roydent Dental Products of Johnson City, Tex.; ESPE™ EXPRESS™ impression material from 3M of St. Paul, Minn. In other embodiments, other materials are used to capture the bite record. 
     In other embodiments, the motion capture station  106  generates motion data  112  representing the movement of the arches relative to one another. In some embodiments, the motion capture station  106  generates the motion data  112  from optical measurements of the dental arches that are captured while the dentition of the patient is moved. In some embodiments, the optical measurements are extracted from image or video data recorded while the dentition of the patient is moved. Additionally, in some embodiments, the optical measurements are captured indirectly. For example, in some embodiments, the optical measurements are extracted from images or video data of a one or more devices that are secured to a portion of the dentition of the patient. In other embodiments, the motion data  112  is generated using other processes. Further, in some embodiments, the motion data  112  includes transformation matrices that represent the position and orientation of the dental arches. Other embodiments of the motion data  112  are possible as well. 
     The example dental lab  114  includes a 3D scanner  116 , design system  118 , rapid fabrication machine  126 , and a restoration fabrication station  132 . Although shown as a single dental lab in this figure, in some embodiments, the dental lab  114  comprises multiple dental labs. For example, in some embodiments, the 3D scanner  116  is in a different dental lab than one or more of the other components shown in the dental lab  114 . Further, in some embodiments, one or more of the components shown in the dental lab  114  are not in a dental lab. For example, in some embodiments, one or more of the 3D scanner  116 , design system  118 , rapid fabrication machine  126 , and restoration fabrication station  132  are in the dental office  102 . Additionally, some embodiments of the system  100  do not include all of the components shown in the dental lab  114 . 
     The example 3D scanner  116  is a device configured to create a three-dimensional digital representation of one or both of the dental impression  108  and the functional bite map  110 . In some embodiments, the 3D scanner  116  generates a point cloud, a polygonal mesh, a parametric model, or voxel data representing the dental impression  108  or the functional bite map  110 . In some embodiments, the 3D scanner  116  generates the digital dental model  120  or the functional bite map data  121 . In some embodiments, the 3D scanner  116  comprises a laser scanner, a touch probe, or an industrial CT scanner. Yet other embodiments of the 3D scanner  116  are possible as well. Further, some embodiments of the system  100  do not include the 3D scanner  116 . For example, in some embodiments of the system  100  where the dental impression station  104  generates a digital dental impression and the motion capture station  106  generates motion data  112 , the 3D scanner  116  is not included. 
     The design system  118  is a system that is configured to generate one or both of the interference model data  122  and the dental restoration data  124 . In some embodiments, the interference model data  122  is three-dimensional digital data that represents the interference model  128  and is in a format suitable for fabrication using the rapid fabrication machine  126 . Similarly, in some embodiments, the dental restoration data  124  is three-dimensional digital data that represents the dental restoration component  130  and is in a format suitable for fabrication using the rapid fabrication machine  126 . 
     In some embodiments, the design system  118  comprises a computing device including user input devices. In some embodiments, the design system  118  includes computer-aided-design (CAD) software that generates a graphical display of one or both of the interference model data  122  and the dental restoration data  124  and allows an operator to interact with and manipulate one or both of the interference model data  122  and the dental restoration data  124 . In some embodiments, the design system  118  comprises digital tools that mimic the tools used by a laboratory technician to physically design a dental restoration. In some other embodiments, the design system  118  comprises a server that partially or fully automates the generation of designs of one or both of the interference model data  122  and the dental restoration data  124 . 
     In some embodiments, the rapid fabrication machine  126  comprises one or more three-dimensional printers, such as the ProJet line of printers from 3D Systems, Inc. of Rock Hill, S.C. Another example of the rapid fabrication machine  126  is stereolithography equipment. Yet another example of the rapid fabrication machine  126  is a milling device, such as a computer numerically controlled (CNC) milling device. In some embodiments, the rapid fabrication machine  126  is configured to receive files in the STL format. Other embodiments of the rapid fabrication machine  126  are possible as well. 
     In some embodiments, the rapid fabrication machine  126  is configured to use the interference model data  122  to fabricate the interference model  128 . In some embodiments, the interference model  128  is a physical structure comprising a surface configured to oppose a dental restoration  134 . In some embodiments, the interference model  128  is formed as a composite of the location of the dental arch opposite the dental restoration  134  along the various bite paths recorded by the functional bite map  110  or the motion data  112 . In some embodiments, the interference model  128  comprises one or more retention structures that are configured to couple to a dental model and properly position the interference model  128  relative to the dental restoration  134 . However, in some other embodiments, the restoration fabrication station  132  does not fabricate the interference model  128 . For example, in some embodiments, a digital interference model is used by the design system  118  and it is not fabricated into a physical apparatus. 
     Additionally, in some embodiments, the rapid fabrication machine  126  is configured to use the dental restoration data  124  to fabricate the dental restoration component  130 . In some embodiments, the dental restoration component  130  is a physical component that is configured to be used as part or all of the dental restoration  134 . For example, in some embodiments, the dental restoration component is milled from zirconium or another material that is used directly as a dental restoration. In other embodiments, the dental restoration component  130  is a mold formed from wax or another material and is configured to be used indirectly (e.g., through a lost was casting or ceramic pressing process) to fabricate the dental restoration  134 . For example, in some embodiments, the dental restoration  134  is formed using traditional techniques (e.g., stacked porcelain or wax-up) using a dental model that includes the interference model  128 . 
     In some embodiments, the restoration fabrication station  132  operates to fabricate a dental restoration  134  for the patient P. In some embodiments, the restoration fabrication station  132  uses the interference model  128  or the dental restoration component  130  produced by the rapid fabrication machine  126 . In some embodiments, the dental restoration  134  is a filling, partial crown, full crown, veneer, or bridge. Other embodiments of the dental restoration  134  are possible as well. In some embodiments, the dental restoration  134  is formed a from an acrylic, ceramic, or metallic material. In some embodiments, the dental impression  108  is used in the fabrication of the dental restoration  134 . In some embodiments, the dental impression  108  is used to form a plaster model of the dentition of the patient P. Additionally, in some embodiments, a model of the dentition of the patient P is generated by the rapid fabrication machine  126 . In some embodiments, the restoration fabrication station  132  comprises equipment and process to perform some or all of the techniques used in traditional dental laboratories to generate dental restorations. Other embodiments of the restoration fabrication station  132  are possible as well. 
     In some embodiments, the dental restoration  134  is seated in the mouth of the patient P in the restoration installation station  136  by a dentist D. In some embodiments, the dentist D confirms that the occlusal surface of the dental restoration  134  is properly defined by instructing the patient P to engage in various bites. 
     Additionally, in some embodiments, the dental office  102  is connected to the dental lab  114  by network  138 . 
     The network  138  is an electronic communication network that facilitates communication between the dental office  102  and the dental lab  114 . An electronic communication network is a set of computing devices and links between the computing devices. The computing devices in the network use the links to enable communication among the computing devices in the network. The network  138  can include routers, switches, mobile access points, bridges, hubs, intrusion detection devices, storage devices, standalone server devices, blade server devices, sensors, desktop computers, firewall devices, laptop computers, handheld computers, mobile telephones, and other types of computing devices. 
     In various embodiments, the network  138  includes various types of links. For example, the network  138  can include one or both of wired and wireless links, including Bluetooth, ultra-wideband (UWB), 802.11, ZigBee, and other types of wireless links. 
     Furthermore, in various embodiments, the network  138  is implemented at various scales. For example, the network  138  can be implemented as one or more local area networks (LANs), metropolitan area networks, subnets, wide area networks (such as the Internet), or can be implemented at another scale. 
       FIG.  2    illustrates an exemplary architecture of a computing device  160  that can be used to implement aspects of the present disclosure, including any of the plurality of computing devices described herein, such as a computing device of the dental impression station  104 , motion capture station  106 , 3D scanner  116 , design system  118 , rapid fabrication machine  126 , restoration fabrication station  132 , or any other computing devices that may be utilized in the various possible embodiments. 
     The computing device illustrated in  FIG.  2    can be used to execute the operating system, application programs, and software modules (including the software engines) described herein. 
     The computing device  170  includes, in some embodiments, at least one processing device  180 , such as a central processing unit (CPU). A variety of processing devices are available from a variety of manufacturers, for example, Intel or Advanced Micro Devices. In this example, the computing device  170  also includes a system memory  182 , and a system bus  184  that couples various system components including the system memory  182  to the processing device  180 . The system bus  184  is one of any number of types of bus structures including a memory bus, or memory controller; a peripheral bus; and a local bus using any of a variety of bus architectures. 
     Examples of computing devices suitable for the computing device  170  include a desktop computer, a laptop computer, a tablet computer, a mobile computing device (such as a smart phone, an iPod® or iPad® mobile digital device, or other mobile devices), or other devices configured to process digital instructions. 
     The system memory  182  includes read only memory  186  and random access memory  188 . A basic input/output system  190  containing the basic routines that act to transfer information within computing device  170 , such as during start up, is typically stored in the read only memory  186 . 
     The computing device  170  also includes a secondary storage device  192  in some embodiments, such as a hard disk drive, for storing digital data. The secondary storage device  192  is connected to the system bus  184  by a secondary storage interface  194 . The secondary storage devices  192  and their associated computer readable media provide nonvolatile storage of computer readable instructions (including application programs and program modules), data structures, and other data for the computing device  170 . 
     Although the exemplary environment described herein employs a hard disk drive as a secondary storage device, other types of computer readable storage media are used in other embodiments. Examples of these other types of computer readable storage media include magnetic cassettes, flash memory cards, digital video disks, Bernoulli cartridges, compact disc read only memories, digital versatile disk read only memories, random access memories, or read only memories. Some embodiments include non-transitory media. Additionally, such computer readable storage media can include local storage or cloud-based storage. 
     A number of program modules can be stored in secondary storage device  192  or system memory  182 , including an operating system  196 , one or more application programs  198 , other program modules  200  (such as the software engines described herein), and program data  202 . The computing device  170  can utilize any suitable operating system, such as Microsoft Windows™, Google Chrome™ OS, Apple OS, Unix, or Linux and variants and any other operating system suitable for a computing device. Other examples can include Microsoft, Google, or Apple operating systems, or any other suitable operating system used in tablet computing devices. 
     In some embodiments, a user provides inputs to the computing device  170  through one or more input devices  204 . Examples of input devices  204  include a keyboard  206 , mouse  208 , microphone  210 , and touch sensor  212  (such as a touchpad or touch sensitive display). Other embodiments include other input devices  204 . The input devices are often connected to the processing device  180  through an input/output interface  214  that is coupled to the system bus  184 . These input devices  204  can be connected by any number of input/output interfaces, such as a parallel port, serial port, game port, or a universal serial bus. Wireless communication between input devices and the interface  214  is possible as well, and includes infrared, BLUETOOTH® wireless technology, 802.11a/b/g/n, cellular, ultra-wideband (UWB), ZigBee, or other radio frequency communication systems in some possible embodiments. 
     In this example embodiment, a display device  216 , such as a monitor, liquid crystal display device, projector, or touch sensitive display device, is also connected to the system bus  184  via an interface, such as a video adapter  218 . In addition to the display device  216 , the computing device  170  can include various other peripheral devices (not shown), such as speakers or a printer. 
     When used in a local area networking environment or a wide area networking environment (such as the Internet), the computing device  170  is typically connected to the network through a network interface  220 , such as an Ethernet interface. Other possible embodiments use other communication devices. For example, some embodiments of the computing device  170  include a modem for communicating across the network. 
     The computing device  170  typically includes at least some form of computer readable media. Computer readable media includes any available media that can be accessed by the computing device  170 . By way of example, computer readable media include computer readable storage media and computer readable communication media. 
     Computer readable storage media includes volatile and nonvolatile, removable and non-removable media implemented in any device configured to store information such as computer readable instructions, data structures, program modules or other data. 
     Computer readable storage media includes, but is not limited to, random access memory, read only memory, electrically erasable programmable read only memory, flash memory or other memory technology, compact disc read only memory, digital versatile disks or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and that can be accessed by the computing device  170 . 
     Computer readable communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term “modulated data signal” refers to a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, computer readable communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, radio frequency, infrared, and other wireless media. Combinations of any of the above are also included within the scope of computer readable media. 
     The computing device illustrated in  FIG.  2    is also an example of programmable electronics, which may include one or more such computing devices, and when multiple computing devices are included, such computing devices can be coupled together with a suitable data communication network so as to collectively perform the various functions, methods, or operations disclosed herein. 
       FIG.  3    is a flow chart illustrating an example method  250  of capturing a dental impression. In some embodiments, the method  250  is performed at the dental impression station  104 . In this example, the method  250  includes operations  252 ,  254 ,  256 , and  258 . 
     At operation  252 , the dentition of the patient P is captured. As described above with respect to  FIG.  1   , in some embodiments, the dentition is captured using a physical impression material and in other embodiments, the dentition is captured using a digital impression system. 
     At operation  254 , the bite record of the patient P is captured. In some embodiments, the bite record comprises information about contact between the upper dentition and lower dentition of the patient. In some embodiments, the bite record is captured in one or more of following positions: centric occlusion, centric relation, and various excursive bite positions. In some embodiments, this operation is not performed and the bite record is not captured. 
     In some embodiments, the bite record is captured using a bite registration material such as bite registration wax or polysiloxane. A bite registration material captures the relationship between the upper and lower dentition of the patient P as indents when the patient P bites into the material. 
     At operation  256 , the restoration prescription is entered. In some embodiments, the restoration prescription comprises information about the type of restoration the doctor D is prescribing for the patient P. In some embodiments, the restoration prescription includes the identity of the tooth or teeth that are being restored, the desired restoration material/s, the desired type of restoration, and additional instructions for fabricating the restoration. In some embodiments, the restoration prescription is entered into a computing device where it is stored. In other embodiments, the restoration prescription is entered into a paper form. Other embodiments are possible as well. 
     At operation  258 , the dental impression  108  is transmitted. In some embodiments, the dental impression  108  is transmitted to the dental lab  114 . In some embodiments, the bite record captured in operation  254  and the restoration prescription entered in operation  256  are transmitted with the dental impression  108 . In some embodiments, the dental impression  108  is transmitted across the network  138  as a digital impression. In other embodiments, the dental impression  108  is transmitted as a physical dental impression or dental model. 
       FIG.  4    is an example process  280  performed at some embodiments of the motion capture station  106 . 
     At operation  282 , the bite capture apparatus is secured to the dental arch that includes the tooth or teeth that are being restored. In some embodiments, the bite capture apparatus is secured so that it is substantially immovable relative the dental arch that includes the tooth or teeth that are being restored. In some embodiments, the bite capture apparatus includes a first surface that is configured to secure the bite capture apparatus to a dental arch, and a second surface that is configured to record the relative movement of the opposite arch. 
     At operation  284 , the patient&#39;s jaw is closed into a first bite position. For example, in some embodiments, the patient&#39;s jaw is closed into a centric bite. In some embodiments, the patient is instructed to bite into the bite capture apparatus. In other embodiments, the dentist or another caregiver may physically guide the patient&#39;s jaw into the bite position. 
     At operation  286 , it is determined whether there are more bite positions to capture. For example, in some embodiments, the patient&#39;s bite will be captured in some or all of the following positions: centric, excursive, left lateral, and right lateral. If there are more bite positions to capture, the process  280  continues to operation  288 , where the patient&#39;s bite is moved into the next bite position. In some embodiments, the patient continues to apply bite force on the bite capture apparatus as the bite is moved to the next bite position. In this manner, the bite capture apparatus record the relative location of the opposing dentition throughout the full bite path. If there are not any more bite positions to capture, the process  280  continues to operation  290 . 
     At operation  290 , the bite capture apparatus is removed from the dentition of the patient. In some embodiments, at this point, the bite capture apparatus will have recorded the relative location of the opposing dentition in all bite positions and all bite paths between those bite positions. 
     At operation  292 , the functional bite map  110  is transmitted. In some embodiments, the functional bite map  110  is transmitted to the dental lab  114 . In some embodiments, the functional bite map  110  comprises the entire bite capture apparatus. In other embodiments, the functional bite map comprises only the portion (e.g., the motion capture layer) of the bite capture apparatus that includes the indents corresponding to the relative locations of the patient P&#39;s dentition in various bite positions and along the paths between those positions. In some embodiments, the functional bite map  110  is transmitted across the network  138  after being digitized using a three-dimensional scanner, such as an impression scanner. In other embodiments, the functional bite map  110  is transmitted as a physical dental impression or dental model. 
       FIG.  5    is an example embodiment of a bite capture apparatus  340  for capturing a functional bite map  110 . In some embodiments, the bite capture apparatus  340  is used at the motion capture station  106 . In some embodiments, the bite capture apparatus includes a securing layer  342 , a separating layer  344 , and a motion capture layer  346 . In some embodiments, the bite capture apparatus  340  is configured to be placed in the patient&#39;s mouth and bitten into by the patient P. 
     The securing layer  342  is an apparatus and is configured to secure the bite capture apparatus  340  to the dentition of the patient. In some embodiments, the securing layer  342  comprises a layer of material. In other embodiments, the securing layer  342  comprises one or mechanical devices configured to secure the bite capture apparatus  340  to one or more of the teeth in patient&#39;s dentition. In some embodiments, the securing layer  342  is configured to be secured to the maxillary arch. In other embodiments, the bite capture layer is configured to be secured mandibular arch. In other embodiments, the securing layer  342  is configured to be secured to either arch. 
     In some embodiments, the securing layer  342  is formed from an impression material, such as vinyl polysiloxane, wax, or other materials. For example, in some embodiments, the securing layer  342  is formed from a thixotropic vinyl polysiloxane, such as BLU-MOUSSE® from Parkell Inc. in Edgewood, N.Y. In some embodiments, the securing layer  342  is warmed and the pressed into the dentition of the patient until it cools and hardens or becomes substantially rigid. In some embodiments, the securing layer  342  is very thin after it is secured to the patient&#39;s dentition. For example, in some embodiments, the securing layer  342  is less than fifty micrometers thick. In yet other embodiments, at least some points on the dentition create holes in the securing layer  342 . In some embodiments, this advantageously minimizes the amount of interference to the patient&#39;s bite that is caused by the presence of the securing layer  342 . 
     The separating layer  344  is configured to separate the securing layer  342  from the motion capture layer  346 . In some embodiments, the separating layer  344  is formed from a thin sheet of foil or plastic. For example, in some embodiments, the separating layer  344  is between 5-50 micrometers thick. 
     The motion capture layer  346  is a layer of material configured to capture the relative motion of the patient&#39;s teeth. In some embodiments, the motion capture layer  346  captures indentations created by the patient&#39;s teeth on the arch opposing the teeth the bite capture apparatus  340  is secured to. In some embodiments, the motion capture layer  346  is formed from wax that remains pliable at room temperature. In other embodiments, the motion capture layer is formed from other materials. 
       FIG.  6    is an illustration of an embodiment of the bite capture apparatus  340  being used to capture bite motion information of a patient P. The upper arch U and the lower arch of the patient P are shown. 
     In this example, the securing layer  342  is secured to the upper arch U and the motion capture layer  346  is configured to capture indentations made by the lower arch L. In this manner, if the patient P moves between different bite positions, the motion capture layer  346  will include indentations that represent the location of the lower arch L relative to the upper arch U in the various bite positions and on the bite paths between those positions. 
       FIG.  7    is an illustration of an embodiment of the bite capture apparatus  340  after the securing layer  342  has formed to the patient P&#39;s dentition. In this example, the securing layer  342  includes securing indents  370 . In some embodiments, the securing indents  370  correspond to the positions and shapes of the teeth the bite capture apparatus  340  is configured to be secured to. In some embodiments, the securing indents  370  are formed when the securing layer  342  is pressed against the teeth of the patient P. In some embodiments, the securing layer  342  is soft and pliable at the time it is pressed against the patient P&#39;s teeth. Further, in some embodiments, the securing layer  342  cures or hardens after a time period. 
       FIG.  8    is an illustration of an embodiment of the bite capture apparatus  340  after the motion capture layer  346  has captured the relative motion from the patient P&#39;s dentition. In this example, the motion capture layer  346  includes motion indents  410 . In some embodiments, the motion indents  410  correspond to the relative positions of the teeth opposite of the securing layer  342 . In some embodiments, the motion indents  410  are formed when the patient P&#39;s jaw is positioned and moved between various bite positions. In some embodiments, the motion indents  410  represent a union of the teeth in multiple bite positions. In some embodiments, the motion capture layer  346  remains soft and pliable throughout the time the patient is wearing the bite capture apparatus  340 . 
       FIG.  9    is another example embodiment of a bite capture apparatus  420  for capturing a functional bite map  110 . In some embodiments, the bite capture apparatus  420  is used at the motion capture station  106 . In some embodiments, the bite capture apparatus  420  includes a motion capture structure  422  and a securing structure  424 . The bite capture apparatus  420  is configured to be secured to a restoration site R of the patient. 
     The motion capture structure  422  is a structure configured to capture the relative motion of the patient&#39;s teeth. In some embodiments, the motion capture structure  422  captures indentations created by the patient&#39;s teeth on the arch opposing the restoration site the bite capture apparatus  420  is secured to. In some embodiments, the motion capture layer  346  is formed from a pliable wax. In other embodiments, the motion capture layer  346  is formed from a combination of wax and a metal, such as copper or aluminum. In other embodiments, the motion capture layer is formed from other materials. 
     In some embodiments, the motion capture structure  422  has a bulbous or spherical shape. In some embodiments, the motion capture structure  422  has a shape that is similar to a large, bulbous tooth. In other embodiments, the motion capture structure  422  has another shape. 
     The securing structure  424  is a structure that operates to secure the bite capture apparatus  420  to the restoration site R. In some embodiments, the securing structure  424  is a cavity that is large enough to fit over the restoration site R. In some embodiments, the securing structure  424  is configured to be secured to the restoration site R by filling the securing structure  424  with a quick-set vinyl polysiloxane material and then placing the bite capture apparatus  420  over the restoration site R. 
     In some embodiments, the motion capture structure  422  is similar to a pre-fabricated crown, such as an anodized crown, except that it is more bulbous and lacks dental anatomy. 
       FIG.  10    is an illustration of the bite capture apparatus  420  after the motion capture structure  422  has captured the relative motion from the opposing dentition O of the patient P. The motion capture structure  422  now includes indents  430  and  432  that were created by the opposing dentition O as it moved through various bite paths. Also shown are the arrows LL and LR. The arrow LL indicates the direction in which the opposing dentition O moves along the lateral left bite path. When the opposing dentition O moves in the direction of the arrow LR, it carves out part of the indent  432 . The arrow LR indicates the direction in which the opposing dentition O moves along the lateral right bite path. When the opposing dentition O moves in the direction of the arrow LR, it carves out part of the indent  430 . 
     In some embodiments, after the motion capture structure  422  has captured indents representing some or all of the bite paths and positions of the patient P, the bite capture apparatus  420  is removed from the restoration site R so that it can be transmitted to the dental lab  114 . In some embodiments, the bite capture apparatus  420  is transmitted to the dental lab  114  by being physically delivered. Once transmitted to the dental lab  114 , in some embodiments, the bite capture apparatus  420  is placed on a plaster model of restoration site R and scanned by the 3D scanner  116 . 
     In other embodiments, after the motion capture structure  422  has captured indents representing some or all of the bite paths and positions of the patient P, the bite capture apparatus  420  is scanned using a digital impressioning system and then transmitted digitally to the dental lab  114 . Other embodiments are possible as well. 
       FIG.  11    illustrates an exemplary architecture of the program modules  200  and program data  202  of the design system  118 . The program modules  200  include a plurality of modules that, when executed by the processing device  180  (shown in  FIG.  2   ), perform one or more operations of the design system  118 . The modules include an interference modeling engine  450  and a restoration design engine  452 . In some embodiments, the program modules  200  includes more, fewer, or different modules than those shown in  FIG.  11   . 
     The program data  202  is stored in a data storage device, such as the memory  182  or the secondary storage device  192  (shown in  FIG.  2   ). In some embodiments, program data  202  includes impression data  454 , bite movement data  456 , the interference model data  122 , and the dental restoration data  124 . In some embodiments, the program data  202  include more, fewer, or different types of data than the data shown in  FIG.  9   . 
     In some embodiments, the data stored in program data  202  can be represented in one or more files having any format usable by a computer. Examples include text files formatted according to a markup language and having data items and tags to instruct computer programs and processes how to use and present the data item. Examples of such formats include html, xml, and xhtml, although other formats for text files can be used. Additionally, the data can be represented using formats other than those conforming to a markup language. 
     The interference modeling engine  450  operates to generate the interference model data  122 . In some embodiments, the interference modeling engine  450  uses the impression data  454  and the bite movement data  456  to generate the interference model data  122 . 
     The restoration design engine  452  operates to generate the dental restoration data  124 . In some embodiments, the restoration design engine  452  uses the impression data  454  and the interference model data  122  to generate the dental restoration data  124 . 
       FIG.  12    is a flow chart illustrating an example method  490  of fabricating the dental restoration  134  using the interference model data  122 . In some embodiments, the method  490  is performed by the interference modeling engine  450  and the restoration design engine  452  using a processor (such as processing device  180 , shown in  FIG.  2   ). In this example, the method  490  includes operations  492 ,  494 , and  496 . 
     At operation  492 , the digital dental model  120  and movement information are received. In some embodiments, the digital dental model  120  is generated from a dental impression  108  that is transmitted digitally by the dental impression station  104  and is converted into the digital dental model  120 . 
     In other embodiments, the digital model is generated from a physical impression. In some of these embodiments, the dental impression  108  is scanned by the 3D scanner  116  to create the digital dental model  120 . In other of these embodiments, a plaster model is formed from the physical impression and then the plaster model is scanned by the 3D scanner  116  to create the digital dental model  120 . Other embodiments are possible as well. 
     In some embodiments, the movement information is received as motion data  112  directly from the motion capture station  106 . In other embodiments, the movement information is received as functional bite map data  121  that is generated by scanning the functional bite map  110  using the 3D scanner  116 . 
     At operation  494 , the interference model data  122  is generated from the dental impression and the movement information. In some embodiments, the interference model data  122  represents a polygonal surface. In other embodiments, the interference model data represents a polygonal model. In some embodiments, the interference model data  122  comprises a surface of the functional bite map data  121 . In other embodiments, the interference model data  122  is generated by sweeping a portion of the digital dental model  120  along the movement path recorded in the motion data  112 . In some embodiments, a portion of the dental arch that opposes the site for the dental restoration  134  is swept along the movement paths. In other embodiments, the interference model data  122  is generated by using Boolean operations to generate a model that the represents the union of the opposing dentition in multiple bite locations. 
     At operation  496 , the restoration is designed using the digital dental model  120  and the interference model. In some embodiments, the interference model is visualized in relation to the restoration site. In some embodiments, an operator utilizes a user interface to design the dental restoration data  124  to avoid contact with the interference model. In other embodiments, the dental restoration data  124  is designed automatically by the restoration design engine to avoid contact with a digital interference model. 
       FIG.  13    is a flow chart illustrating an example method  530  of fabricating the interference model  128  using the interference model data  122 . In some embodiments, the method  530  is performed by the restoration design engine  452  using a processor (such as processing device  180 , shown in  FIG.  2   ). In this example, the method  530  includes operations  532 ,  534 ,  536 ,  538 ,  540 ,  542 ,  544 ,  546 ,  548 , and  550 . 
     At operation  532  it is determined whether a functional bite map  110  or motion data  112  is provided. If a functional bite map  110  is provided, the method  530  continues to operation  534 . If not, the method  530  continues to operation  536 . 
     At operation  534 , a digital surface is generated from the functional bite map  110 . 
     At operation  536 , a digital model of the opposing dentition is generated. 
     At operation  538 , the digital model of the opposing dentition is swept along the movement path/s recorded in the motion data  112 . 
     At operation  540 , an interference surface opposing the restoration site is extracted. In some embodiments, the interference surface is extracted from the digital surface generated from the functional bite map  110  at operation  534 . In other embodiments, the interference surface is extracted from the sweep of the digital model of the opposing dentition at operation  538 . In some embodiments, only a portion of the interference surface is extracted. For example, in some embodiments, a portion of the interference surface directly opposite the restoration site is extracted. In other embodiments, a larger portion of the occlusal surface is extracted. For example, in some embodiments, a portion of the interference surface opposing the teeth adjacent to the restoration site is extracted as well. 
     At operation  542 , it is determined whether a physical interference model will be Fabricated. If so, the method  530  continues to operation  544 . If not, the method  530  ends and the interference surface extracted at operation  540  is ready for use in digital dental design. 
     At operation  544 , a retention structure is built. The retention structure operates to align the interference surface to a physical model of the patient P&#39;s dentition. In some embodiments, the retention structure is configured to secured the interference surface to the patient P&#39;s dentition. In other embodiments, the retention structure is configured to align the interference surface without securing it. In some embodiments, the retention structure is a band, clasp, or surface that matches the contour of the adjacent dentition. In other embodiments, the retention structure is a male or female connector that is configured to mate with an opposite connector that is added to the physical model of the patient P&#39;s dentition. Other embodiments are possible as well. 
     At operation  546 , the retention structure is joined to the interference structure to form an integral digital interference model. 
     At operation  548 , interferences with the adjacent dentition are removed from the interference surface. In some embodiments, this ensures that interferences with the adjacent teeth do not prevent the interference surface from being properly aligned relative to the restoration site. 
     At operation  550 , the interference model data is transmitted to the rapid fabrication machine  126  for fabrication. 
       FIG.  14    is a cross-section illustration of an example interference model  128 , including an interference surface  580 . Also shown is the restoration site R and the opposing dentition O. 
     The interference surface  580  is a surface that is operates to indicate where a dental restoration would interfere with the opposing dentition O in at least one of the bite positions or along one of the paths between bite positions. In the example shown in  FIG.  14   , the interference surface  580  corresponds to the inverse of the indents  430  and  432  in the bite capture apparatus  420  shown in  FIG.  10   . 
     In some embodiments, the cross-section of the interference surface  580  is larger than the cross-section of the opposing dentition O because the interference surface  580  represents the union of the opposing dentition O in multiple bite locations. In some embodiments, the interference model  128  is used to design a dental restoration  134  for the restoration site R. For example, in some embodiments, the dental restoration  134  is designed so that it does not contact or interfere with the interference surface  580 . In this manner, the dental restoration  134  will not contact or interfere with the opposing dentition O in any of the bite positions that were used to generate the interference surface  580 . 
       FIG.  15    is a schematic diagram of an embodiment of the interference model  128 . In this example, the interference model  128  includes the interference surface  580  and the retention structure  610 . In this example, the interference surface  580  occupies only a portion of the dental arch. In some embodiments, the retention structure  610  is generated to follow the dental arch of the opposing dentition O. In some embodiments, the retention structure  610  comprises at least a portion of the opposing dentition O. 
       FIG.  16    is an illustration of an example embodiment of the interference model  128  joined with a dental model  640 . The interference model  128  includes the interference surface  580 , and the opposing dentition surface  646 . The dental model  640  includes a model  642  of the restoration site R, and a model  644  of the adjacent dentition. Also shown are retention structures  648   a - b . The retention structures  648   a - b  are formed from lower pins  652   a - b  and upper pins  650   a - b . The lower pins  652   a - b  extend from the dental model  640  and are configured to mate with the upper pins  650   a - b , which extend from the interference model  128 . When the lower pins  652   a - b  are mated with the upper pins  650   a - b , the interference model  128  is properly aligned with the dental model  640 . Some embodiments, include more or fewer of the retention structures  648   a - b . Additionally, some embodiments, include different types of retention structures. 
       FIG.  17    is an illustration of another example embodiment of the interference model  128  joined with a dental model  640 . The interference model  128  includes the interference surface  580  and retention clips  680   a - b . The retention clips  680   a - b  are configured to mate with the occlusal surface of the model  644  of the adjacent dentition. When the retention clips  680   a - b  are mated with the model  644  of the adjacent dentition, the interference model  128  is properly aligned with the dental model  640 . Some embodiments, include more or fewer of the retention clips  680   a - b.    
       FIG.  18    is an illustration of the dental model  640 . In this illustration, the bite capture apparatus  420  is also shown. The bite capture apparatus  420  is disposed on the model  642  of the restoration site. In some embodiments, the interference surface  580  (shown, for example, in  FIGS.  16 - 17   ) fits snugly over the surface of the bite capture apparatus  420 . In fact, in some embodiments, the bite capture apparatus  420  is disposed on the model  642  of the restoration site and scanned by the 3D scanner  116  as part of the process of generating the interference surface  580 . 
       FIG.  19    is a flow chart illustrating an example method  720  of fabricating the dental restoration  134  using the interference model  128 . In some embodiments, the method  720  is performed at the restoration fabrication station  132 . In this example, the method  720  includes operations  722 ,  724 ,  726 , and  728 . 
     At operation  722 , the dental restoration  134  is fabricated. In some embodiments, the dental restoration  134  is designed digitally and fabricated using the rapid fabrication machine  126 . In other embodiments, the dental restoration  134  is fabricated using more traditional methods, such as hand waxing and lost casting, or porcelain stacking. Additionally, in some embodiments, operation  722  is performed using the a wax-up of the dental restoration  134  rather than the dental restoration  134  itself. 
     At operation  724 , the dental restoration  134  is compared to the interference model  128 . 
     At operation  726 , it is determined whether the dental restoration  134  interferes with the interference model  128 . If so, the method  720  continues to operation  728 . If not, the method  720  ends. 
     At operation  728 , the dental restoration  134  is adjusted. After operation  728 , the method returns to operation  724 . This loop through operations  724 - 726  repeats until it is determined that the dental restoration  134  does not interfere with the interference model  128 . 
       FIG.  20    is a flow chart illustrating an example method  750  of designing the dental restoration data  124  using the interference model data  122 . In some embodiments, the method  750  is performed by the design system  118 . In this example, the method  750  includes operations  752 ,  754 ,  756 , and  758 . 
     At operation  752 , the dental restoration data  124  and the interference model data  122  are received. 
     At operation  754 , in some embodiments, a distance between a surface represented by the dental restoration data  124  and a surface represented by the interference model data  122  is calculated. In some embodiments, the distance is calculated by determining for each vertex on the surface represented by the dental restoration data  124  a nearest point on the surface represented by the interference model data  122  and then calculating the distance between the vertex and the point. In some embodiments, the distance is calculated as the length of a three dimensional vector between the vertex and the point. In other embodiments, the distance is calculated as the length of the projection of the three dimensional vector between the vertex and the point in the occlusal direction. In other embodiments, the distance is only calculated for vertices that intersect with surface represented by the interference model data  122 . Other embodiments are possible as well. 
     At operation  756 , in some embodiments, colors are assigned to regions of a surface represented by the dental restoration data  124  based on the distances calculated in operation  754 . In some embodiments, colors are assigned to each vertex of the dental restoration data  124 . In other embodiments, colors are assigned to each facet of the surface represented by the dental restoration data  124 . In yet other embodiments, colors are assigned to only the facets or vertices that intersect with the surface represented by the interference model data  122 . Other embodiments are possible as well. 
     At operation  758 , the dental restorations represented by the dental restoration data  124  is visualized. 
       FIG.  21    is an illustration of a cross-sectional view of the interference model data  122  and the dental restoration data  124 . The interference model data  122  includes an interference surface  790 . The dental restoration data  124  includes an exterior surface  792  and an interior surface  794 . In some embodiments, an illustration similar to  FIG.  21    is displayed by a user interface of the design system  118 . 
     The interference surface  790  is a three-dimensional surface that represents the union of the opposing dentition O in multiple bite locations. In some embodiments, the exterior surface  792  is a three-dimensional surface representing the exterior surface of the dental restoration  134 . The interior surface  794  is a three-dimensional surface representing the interior of the dental restoration  134 . In some embodiments, the interior surface  794  approximately follows the surface of the restoration site R. In some embodiments, the interior surface  794  is offset from the surface of the restoration site R by an offset amount, such as 10-200 micrometers. 
     In some embodiments, the interference surface  790  is compared to the exterior surface  792  to generate a color map representing the interferences between the dental restoration data  124  and the interference model data  122 . 
       FIG.  22    is an illustration of a cross-sectional view of the dental restoration data  124  with an example embodiment of a color map  820  on the exterior surface  792 . The color map  820  includes regions  812 ,  814 ,  816 , and  818 . In some embodiments, the illustration in  FIG.  22    is displayed by a user interface of the design system  118 . 
     In the example shown, the regions  812 ,  814 ,  816 , and  818  are displayed in different colors that represent the distance between the regions and the interference surface  790  (shown in  FIG.  21   ). Although the embodiment shown in  FIG.  22    includes four regions, other embodiments include more or fewer regions. 
     In the example shown, the region  812  is colored a first color. Here, the first color indicates that the region  812  interferes with the interference surface  790 . For example, in some embodiments, the first color indicates that the vertices in the region  812  intersect with (i.e., are inside of) the interference surface  790 . In some embodiments, the first color also indicates that the vertices are very close to interfering with the interference surface. For example, in some embodiments, the first color is used to indicate that a vertex either intersects with the interference surface  790  or is less than 10 micrometers away from the interference surface  790 . In this manner, the color map  820  allows for small errors in the impressioning and scanning processes. In some embodiments, the first color is color that indicates to stop, such as red. In other embodiments, the first color is a different color. 
     In the example shown, the regions  814  and  818  are colored a second color. Here, the second color indicates that the regions  814  and  818  are close to interfering with the interference surface  790 . For example, in some embodiments, the second color indicates that the vertices in the regions  814  and  818  are between 0 and 100 micrometers away from the interference surface  790 . In some embodiments, the second color is a color that indicates to use caution, such as yellow or orange. In other embodiments, the second color is a different color. 
     In the example shown, the region  812  is colored a third color. Here, the third color indicates that the region  812  is not close to interfering with the interference surface  790 . For example, in some embodiments, the third color indicates that the vertices in the region  812  are at least 100 micrometers away from the interference surface  790 . In some embodiments, the third color is a neutral color, such as white, gray, tan, or ivory. In other embodiments, the third color is a different color. 
     Although, the color map  820  includes three colors, in other embodiments more or fewer colors are used. Additionally, in other embodiments, other distance ranges are used for the color map. 
       FIG.  23    is a schematic block diagram illustrating an example of a system  900  for simulating incisal guide paths to fabricate a provisional restoration  914 . In this example, the system  900  includes a dental office  102 . However, in other embodiments, the system  900  also includes a dental lab. 
     The example dental office  102  includes the dental impression station  104 , the motion capture station  106 , the 3D scanner  116 , a provisional design system  902 , the rapid fabrication machine  126 , a provisional restoration fabrication station  912 , and a provisional restoration installation station  916 . Also shown are the dental impression  108 , functional bite map  110 , motion data  112 , digital dental model  120 , functional bite map data  121 , provisional restoration mold data  904 , incisal guide data  906 , provisional restoration mold  908 , incisal guide model  910 , and provisional restoration  914 . Additionally, the patient P and the dentist D are shown. 
     Although shown as a single dental office in this figure, in some embodiments, the dental office  102  comprises multiple dental offices. For example, in some embodiments, one or more of the dental impression station  104 , the motion capture station  106 , the 3D scanner, the provisional design system  902 , the rapid fabrication machine  126 , and the provisional restoration fabrication station  912  are in a different dental office than the provisional restoration installation station  916 . Further, in some embodiments, one or more of the dental impression station  104 , the motion capture station  106 , the provisional design system  902 , the rapid fabrication machine  126 , the provisional restoration fabrication station  912 , and the provisional restoration fabrication station  912  are not in a dental office. 
     The operation of the dental impression station  104 , the motion capture station  106 , and the 3D scanner  116  has been described with system  100  (shown in  FIG.  1   ). 
     These components operate in a similar manner in system  900 . However, in some embodiments, one or both of the motion capture station  106  and the 3D scanner  116  are not included in the system  900 . For example, in some embodiments, the digital dental model  120  is generated at the dental impression station  104  using a digital impression system. In some of these embodiments, the 3D scanner is not included. Additionally, as will be described below, some embodiments do not require the motion data  112  or the functional bite map data  121  and thus the motion capture station  106  is not included. 
     The provisional design system  902  is a system that is configured to generate one or both of provisional restoration mold data  904  and the incisal guide data  906 . In some embodiments, the provisional restoration mold data  904  is three-dimensional digital data that represents the provisional restoration mold  908  and is in a format suitable for fabrication using the rapid fabrication machine  126 . Similarly, in some embodiments, the incisal guide data  906  is three-dimensional digital data that represents the incisal guide model  910  and is in a format suitable for fabrication using the rapid fabrication machine  126 . 
     In some embodiments, the provisional design system  902  comprises a computing device including user input devices. In some embodiments, the provisional design system  902  includes computer-aided-design (CAD) software that generates a graphical display of one or both of the provisional restoration mold data  904  and the incisal guide data  906  and allows an operator to interact with and manipulate one or both of the provisional restoration mold data  904  and the incisal guide data  906 . In some embodiments, the provisional design system  902  comprises digital tools that mimic the tools used by a laboratory technician to physically design a provisional dental restoration. In some other embodiments, the provisional design system  902  comprises a server that partially or fully automates the generation of designs of one or both of the provisional restoration mold data  904  and the incisal guide data  906 . 
     In some embodiments, the provisional restoration mold  908  is used at the provisional restoration fabrication station  912  to fabricate the provisional restoration  914 . In some embodiments, the provisional restoration fabrication station  912  and the provisional restoration installation station  916  are integrated and the provisional restoration mold  908  is used to fabricate the provisional restoration  914  in the mouth of the patient P. In other embodiments, the incisal guide model  910  is used at the provisional restoration fabrication station  912  to fabricate the provisional restoration  914  on an articulator. 
     In some embodiments, the provisional restoration  914  is seated in the mouth of the patient P in the provisional restoration installation station  916  by the dentist D. 
       FIG.  24    illustrates an exemplary architecture of the program modules  200  and program data  202  of the provisional design system  902 . The program modules  200  include a plurality of modules that, when executed by the processing device  180  (shown in  FIG.  2   ), perform one or more operations of the provisional design system  902 . The modules include a provisional restoration mold design engine  950  and an incisal guide engine  952 . In some embodiments, the program modules  200  includes more, fewer, or different modules than those shown in  FIG.  24   . 
     The program data  202  is stored in a data storage device, such as the memory  182  or the secondary storage device  192  (shown in  FIG.  2   ). In some embodiments, program data  202  includes impression data  454 , bite movement data  456 , provisional restoration mold data  904 , and incisal guide data  906 . In some embodiments, the program data  202  include more, fewer, or different types of data than the data shown in  FIG.  9   . 
     In some embodiments, the data stored in program data  202  can be represented in one or more files having any format usable by a computer. Examples include text files formatted according to a markup language and having data items and tags to instruct computer programs and processes how to use and present the data item. Examples of such formats include html, xml, and xhtml, although other formats for text files can be used. Additionally, the data can be represented using formats other than those conforming to a markup language. 
     The provisional restoration mold design engine  950  operates to generate the provisional restoration mold data  904 . In some embodiments, the provisional restoration mold design engine  950  uses the impression data  454  and the bite movement data  456  to generate the provisional restoration mold data  904 . 
     The incisal guide engine  952  operates to generate the incisal guide data  906 . In some embodiments, the incisal guide engine  952  uses the impression data  454  and the bite movement data  456  to generate the incisal guide data  906 . 
       FIG.  25    is a flow chart illustrating an example method  990  of using the system  900  to fabricate and install the provisional restoration  914 . In some embodiments, the method  990  is performed in the dental office  102 . In other embodiments, the method  990  is performed in multiple locations, such as one or more dental offices and dental laboratories. In this example, the method  990  includes operations  992 ,  994 ,  996 , and  998 . 
     At operation  992 , the dental impression  108  is captured. At operation  994 , the digital dental model  120  is generated. In some embodiments, the digital dental model  120  is generated by using the 3D scanner  116  to scan the dental impression  108 . In other embodiments, the dental impression station  104  generates the digital dental model  120  directly. 
     At operation  996 , the provisional restoration mold  908  is fabricated. In some embodiments, the provisional restoration mold  908  is fabricated by the rapid fabrication machine  126  using the provisional restoration mold data  904 . In some embodiments, the provisional restoration mold data  904  is generated by the provisional design system  902  using the digital dental model  120 . In some embodiments, the provisional design system  902  also uses one or both of the functional bite map data  121  and motion data  112  to generate the provisional restoration mold data  904 . 
     At operation  998 , the provisional restoration  914  is fabricated and installed in the patient P&#39;s mouth using the provisional restoration mold  908 . In some embodiments, the provisional restoration  914  is fabricated by filling the provisional restoration mold  908  with a provisional material such as an acrylic resin or bis-acrylic. Some examples of acrylic resins include polymetheyl methacrylate and polyethyl methacrylate. In some embodiments, other materials are used as well. 
     In some embodiments, once the provisional restoration mold  908  is filled with the provisional material, the provisional restoration mold  908  is placed over the restoration site in the patient P&#39;s mouth. In some embodiments, the provisional restoration mold  908  is aligned with the restoration site using landmarks or contours of adjacent teeth. After the provisional material has hardened, the provisional restoration mold  908  is removed. In some embodiments, the dentist D adjusts and polishes the provisional material to finish the provisional restoration  914 . 
       FIG.  26    is a flow chart illustrating another example method  1030  of using the system  900  to fabricate and install the provisional restoration  914 . In some embodiments, the method  1030  is performed in the dental office  102 . In other embodiments, the method  1030  is performed in multiple locations, such as one or more dental offices and dental laboratories. In this example, the method  1030  includes operations  1032 ,  1034 ,  1036 , and  998 . 
     At operation  1032 , the pre-preparation dental impression is captured. The pre-preparation dental impression represents the dentition of the patient P before the dentist has prepared the restoration site for the provisional restoration  914 . In some embodiments, the pre-preparation dental impression provides information regarding the proper anatomy and contour of the provisional restoration  914 . The pre-preparation dental impression can be captured using any digital or physical impression techniques that are used to capture dental impressions. 
     At operation  1034 , the provisional restoration mold  908  is fabricated using the pre-preparation dental impression. In some embodiments, the interior surface of the provisional restoration mold  908  is fabricated to match the surface of the pre-preparation dentition at the restoration site. Additionally, in some embodiments, the interior surface of the provisional restoration mold  908  is fabricated to match the surface of the pre-preparation dentition with an offset. For example, in some embodiments, the interior surface of the provisional restoration mold  908  is offset from the surface of the pre-preparation dentition by 20-100 micrometers. 
     Additionally, in some embodiments, the interior surface of the provisional restoration mold  908  is shifted in the vertical dimension by an amount corresponding to a desired change in the vertical dimension of occlusion of the patient&#39;s dentition. The vertical dimension of occlusion refers to the distance between the maxilla and mandible when in maximum intercuspation. 
     In some embodiments, the dentist D may desire to increase the vertical dimension of occlusion of the patient P by 1 mm. The dentist D may accomplish this by increasing the height of the dentition at one more of the contact locations during maximum intercuspation using one or more restorations. Conversely, the dentist D may desire to lower the vertical dimension of occlusion of the P by 1 mm instead. The dentist D may accomplish this by removing dentition to lower the height of one or more of the contact locations during maximum intercuspation. In either case, in some embodiments, the interior surface of the provisional restoration mold is shifted by a corresponding amount in the vertical dimension as well. In this manner, the contour of the provisional restoration  914  matches the original contour and is located in the same position relative to the opposing dentition even after the vertical dimension of occlusion is adjusted. 
     At operation  1036 , the dentist D prepares the restoration site. In some embodiments, the dentist D prepares the restoration site by removing some of the structure of the patient P&#39;s dentition so that the restoration site is prepared to receive a dental restoration. 
     Next, at operation  998 , the provisional restoration  914  is fabricated and installed in the patient P&#39;s mouth using the provisional restoration mold  908 . 
       FIG.  27    is a flow chart illustrating an example method  1080  of using the system  900  to fabricate a dental restoration based on the provisional restoration  914 . In some embodiments, the method  1080  is performed in the dental office  102 . In other embodiments, the method  1080  is performed in multiple locations, such as one or more dental offices and dental laboratories. In this example, the method  1080  includes operations  1082 ,  1084 ,  1086 , and  1088 . 
     At operation  1082  the provisional restoration  914  is installed in the patient P. In some embodiments, the provisional restoration  914  is fabricated and installed using the method  1030  (shown in  FIG.  26   ). In other embodiments, the provisional restoration  914  is fabricated using the method  990  (shown in  FIG.  25   ). In other embodiments, the provisional restoration  914  is fabricated using other methods. 
     At operation  1084 , the provisional restoration  914  is evaluated in the patient P&#39;s mouth. In some embodiments, the patient P wears the provisional restoration  914  for an evaluation time period and provides feedback to the doctor D. Additionally, in some embodiments, the doctor D inspects the provisional restoration  914  for signs of wear after the evaluation time period. 
     At operation  1086 , it is determined whether the provisional restoration  914  is satisfactory. In some embodiments, the doctor D determines whether the provisional restoration  914  is satisfactory based on the evaluation of operation  1084 . If the provisional restoration  914  is satisfactory, the method  1080  continues to operation  1090 . If the provisional restoration  914  is not satisfactory the method  1080  continues to operation  1088 . 
     At operation  1088 , the provisional restoration  914  is adjusted or replaced. In some embodiments, the provisional restoration  914  is adjusted using an abrasive wheel or another carving tool without being removed from the patient P&#39;s mouth. In other embodiments, the provisional restoration mold data  904  is adjusted using the provisional design system  902 . In these embodiments, the provisional restoration mold data  904  is adjusted based on the evaluation of operation  1084 . Then, the provisional restoration mold  908  is fabricated by the rapid fabrication machine  126  using the provisional restoration mold data  904  after it has been adjusted. Then, the provisional restoration mold  908  is used to fabricate and install a new provisional restoration. After the provisional restoration  914  is adjusted or replaced, the method  1080  returns to operation  1084  so that the new provisional restoration can be evaluated. 
     At operation  1090 , a dental restoration is fabricated based on the provisional restoration  914 . In some embodiments, the dental restoration is fabricated using data acquired by scanning the provisional restoration  914  with the 3D scanner  116 . In other embodiments, the dental restoration is fabricated using the provisional restoration mold data  904 . In some embodiments, one or both of the provisional restoration mold data  904  and the data acquired by scanning the provisional restoration  914  are used by the design system  118  (shown in  FIG.  1   ) to design the dental restoration data  124 . The dental restoration data  124  is then used to fabricate the dental restoration  134 . 
       FIG.  28    is a cross-sectional illustration of the anterior dentition of the patient P. The tooth T and the opposing dentition O are shown. The tooth T represents a tooth that the dentist D intends to replace or repair with a restoration. The opposing dentition O represents the opposing tooth or teeth on the opposite arch of the tooth T. 
     Also shown is the original contour C and the incisal guide path G. The original contour C represents the surface of the tooth T prior to being worn away by the opposing dentition O. The incisal guide path G represents the worn surface of the tooth T. 
     In some embodiments, the shape of the incisal guide path G is preserved when the tooth T is replaced by the provisional restoration  914  or the dental restoration  134 . In some embodiments, by preserving the incisal guide path G the provisional restoration  914  and the dental restoration  134  fit more harmoniously with the opposing dentition O and are less likely to fracture due to wear from the opposing dentition O. In some embodiments, the provisional restoration mold  908  is fabricated with an interior contour that preserves the incisal guide path G. 
       FIG.  29    is an illustration of an example of an embodiment  908   a  of the provisional restoration mold  908 . The provisional restoration mold  908   a  includes an interior surface  1130 , including incisal guide path surface  1132 , exterior surface  1134 , and registration structures  1136   a - b , including registration surfaces  1138   a - b . In some embodiments, the provisional restoration mold  908   a  is formed from a bio-compatible material that is safe for temporary in-mouth placement. For example, in some embodiments, the provisional restoration mold  908   a  is formed by the rapid fabrication machine  126  from an acrylic material such as Object MED610, available from STRATSYS LTD. of Eden Prairie, Minn. 
     The interior surface  1130  operates to define the shape of some or all of the exterior surface of the provisional restoration  914 . In some embodiments, the incisal guide path surface  1132  matches the contour of the incisal guide path G. In some embodiments, the incisal guide path surface  1132  is offset vertically to compensate for an adjustment to the patient P&#39;s vertical dimension of occlusion. 
     The exterior surface  1134  is offset from the interior surface  1130  to form the walls of the provisional restoration mold. In some embodiments, the exterior surface  1134  is offset from the interior surface  1130  uniformly to generate walls with substantially uniform thickness. In other embodiments, the exterior surface  1134  is offset from the interior surface  1130  non-uniformly to generate walls with a non-uniform thickness. For example, in some embodiments, the exterior surface  1134  is offset from the interior surface  1130  by a smaller distance in the interproximal walls than on the labial and lingual walls of the provisional restoration mold  908   a.    
     The registration structures  1136   a - b  operate to align the provisional restoration mold  908   a.  In some embodiments, the registration surfaces  1138   a - b  match the labial surfaces of the dentition adjacent to the restoration site. In some embodiments, the registration surfaces  1138   a - b  are configured to be fit against a specific portion of the labial surfaces of the dentition adjacent to the restoration site. In this manner, the dentist D can determine that the provisional restoration mold  908   a  is properly aligned with the prep site when the registration surfaces  1138   a - b  fit properly against the dentition adjacent to the restoration site. Although two of the registration structures  1136   a - b  are included in the embodiment of the provisional restoration mold  908   a  shown in  FIG.  29   , in other embodiments more or fewer registration structures are included. Additionally, in some embodiments, other registration structures are used to align the provisional restoration mold  908   a  with the restoration site. 
       FIG.  30    is an illustration of an alternative embodiment  908   b  of the provisional restoration mold  908 . The embodiment shown in  FIG.  30    is similar to the embodiment  908   a  shown in  FIG.  29   . 
     The embodiment shown in  FIG.  30    includes a registration structure  1142 , including registration surface  1144 . Additionally, the interior surface  1130  and the exterior surface  1134  do not fully surround the restoration site. Instead, the interior surface  1130  and the exterior surface  1134  are open along the proximal walls. In some embodiments, this allows the provisional restoration to be formed in contact with the adjacent dentition. 
     The registration structure  1142  is a physical structure configured to align the provisional restoration mold  908   b  with the restoration site. In some embodiments, the registration surface  1144  matches the incisal edge of the adjacent dentition. In this manner, the dentist D can determine that the provisional restoration mold  908   b  is properly aligned with restoration site when the provisional restoration mold is fully seated on the adjacent dentition. Although only one registration structure  1142  is shown in  FIG.  30   , other embodiments include additional registration structures. 
       FIG.  31    is a cross-sectional illustration of a provisional restoration mold  908  being used to form a provisional restoration  914  on a restoration site R. As shown in this figure, the incisal guide path surface  1132  of the provisional restoration mold  908  generates an incisal guide path G on the provisional restoration  914  that matches the original incisal guide path. 
       FIG.  32    is a cross-sectional illustration of an articulator  1200  being used with an incisal guide model  910 . In some embodiments, the articulator  1200  includes a lower structure  1202 , an upper structure  1204 , and a vertical support  1206 , including a socket  1208 . 
     The lower structure  1202  is a rigid structure and includes a lower model mounting plate  1210  and an incisal guide model mounting plate  1212 . The lower model mounting plate  1210  operates to secure a lower arch dental model  1214  to the articulator  1200 . The incisal guide model mounting plate  1212  operates to secure an incisal guide model  910  to the articulator  1200 . 
     The upper structure  1204  is a rigid structure and includes an upper model mounting plate  1216  and a guide pin  1218 . The upper model mounting plate  1216  operates to secure an upper arch dental model  1220  to the articulator  1200 . The guide pin  1218  is a rigid structure that includes a tip  1222 . The guide pin  1218  is rigidly secured to the upper structure  1204  and is configured to be immovable relative to the upper structure  1204  during operation of the articulator  1200 . The tip  1222  of the guide pin  1218  is configured to move along the surface of the incisal guide model  910 . As the guide pin  1218  moves along the surface of the incisal guide model  910 , the upper structure  1204  and the upper arch dental model  1220  move in a manner that replicates the motion of the patient P&#39;s jaw. 
     The vertical support  1206  is a rigid structure that is rigidly coupled to the lower structure  1202  and is configured to be immovable relative to the lower structure  1202  during operation of the articulator  1200 . The vertical support  1206  includes a socket  1208 . The socket is configured to couple with the upper structure  1204 . In some embodiments, the socket  1208  is configured to allow the upper structure  1204  to rotate and move while remaining coupled. In this manner, the socket  1208  approximates the condyle of the patient&#39;s jaw. 
     The incisal guide model  910  is a model that forms a surface that corresponds to the incisal guide path G. In some embodiments, as the guide pin  1218  moves across the surface of the incisal guide model  910 , the upper arch dental model  1220  moves relative to the lower arch dental model  1214  in a manner that is similar to the actual motion of the patient P&#39;s jaw. In some embodiments, as the guide pin  1218  moves across the incisal guide model  910 , a surface of the upper arch dental model  1220  that corresponds to the incisal guide path G contacts the lower arch dental model  1214 . In this manner, the provisional restoration  914  can be fabricated on the articulator to preserve the incisal guide path G. 
     In some embodiments, the incisal guide model  910  is fabricated using the rapid fabrication machine  126  based on the incisal guide data  906 . In some embodiments, the provisional design system  902  generates the incisal guide data  906  from the digital dental model  120 . In other embodiments, the provisional design system  902  generates the incisal guide data  906  by moving the lower arch along the paths defined in the motion data. In some embodiments, the incisal guide data  906  is generated by sweeping the lower arch model data through all of the bite positions recorded in the functional bite map data  121  or the motion data  112 . 
     Additionally, in some embodiments, the incisal guide data  906  is generated from a pre-preparation impression of the lingual surface of the upper arch of the patient P. In some embodiments, the incisal guide data  906  is formed by inverting the lingual surface of the upper arch of the patient P. Similarly, in some embodiments, the incisal guide data  906  is formed by inverting the surface formed by sweeping the lower arch model through all of the bite positions and paths. In this manner, the incisal guide model  910  forms a surface that causes motion on the articulator that mimics the motion captured from the patient. Other embodiments are possible as well. 
     In some embodiments, the incisal guide model  910  includes one or more retention structures  1224  and  1226 . The retention structures  1224  and  1226  are configured to align and secure the incisal guide model  910  to the articulator  1200 . 
     In the example shown, the retention structure  1224  comprises a peg that is configured to fit in a corresponding hole in the incisal guide model mounting plate  1212 . In some embodiments, the retention structure  1224  includes a registration grove or ridge to properly align the incisal guide model  910  to the incisal guide model mounting plate  1212 . In the example shown, the retention structure  1226  comprises a clip that is configured to fit around the edge of the incisal guide model mounting plate  1212 . 
     In some embodiments, the retention structures  1224  and  1226  are included in the incisal guide data. Additionally, some embodiments include more, fewer, or different retention structures. 
     Some embodiments include one or more of the following: 
     A method of generating a dental restoration to restore an anterior tooth of a patient, comprising: generating an incisal guide path, using a computing device, corresponding to the lingual surface of the anterior tooth; fabricating an incisal guide path structure based on the incisal guide path; and using the incisal guide path structure to generate the dental restoration. 
     The method, wherein the dental restoration is a provisional restoration. 
     The method, wherein the dental restoration is a permanent restoration. 
     The method, wherein the incisal guide path structure is a mold configured to be filled with a provisional material and placed over the restoration site, wherein the mold comprises a cavity and an alignment structure, the cavity being defined by an interior surface of the mold, a portion of the interior surface having a contour that matches the incisal guide path, and the alignment structure being configured to align the mold with the restoration site. 
     The method, wherein the incisal guide path structure is an incisal guide plane configured to direct the movement of an articulator configured to articulate a physical dental model representing a dentition of the patient. 
     The method, wherein the incisal guide path is generated from an pre-preparation impression of the anterior tooth. 
     The method, wherein the incisal guide path is generated using an impression of a dentition of the patient and motion data corresponding to the positions of an upper arch of the dentition of the patient relative to a lower arch of the dentition of the patient. 
     The various embodiments described above are provided by way of illustration only and should not be construed to limit the claims attached hereto. Those skilled in the art will readily recognize various modifications and changes that may be made without following the example embodiments and applications illustrated and described herein, and without departing from the true spirit and scope of the following claims.