Device for scanning a dental model

IS 2 333 262 T3

DESCRIPTION

Method for the exploration of a dental model.

The invention relates to a method for the exploration of a dental model.

Devices for scanning dental models are known to obtain a data set that digitally represents the dental model. Such data sets can be used for automated production of dental prostheses (see, for example, EP-A2-0913130).

If different data sets respectively represent only a part of a model, however, the two data sets present an area of ​​overlap, in which they represent the same part of the model, then the two data sets can be grouped by a method pairing. The data in the area of ​​overlap is used to establish or determine the relative arrangement of individual data sets. Typically, data sets represent a three-dimensional surface shape. Therefore, the pairing is called 3D pairing. Matching can also group a larger number of data sets, such as 5, 10, 15, or 20 data sets, down to a single data set.

Dental models can exist as so-called segmented dental models. These models have a removable model part and model part holder. Individual model parts correspond to individual sections of a denture model, such as one or more teeth or adjacent tooth sites. When model parts are held by the model part holder, they represent a denture or a part thereof. The model part holder defines the relative situation of the individual model parts to each other.

A normal adult denture comprises 32 tooth sites, 16 in the upper jaw and 16 in the lower jaw. At each tooth site there is usually one tooth. However, at a tooth site there may also be a dental prosthesis or parts thereof or implants or parts thereof such as implant posts or a residual tooth area or a gum area. In the case of a gap between the teeth, a gingiva area generally occurs at the tooth site. A tooth can also comprise dental prostheses such as fillings, inlays, overlays or the like. A residual tooth area can be a defective tooth or a tooth prepared (carved) by the dentist. Multiple tooth sites can also be occupied by a dental prosthesis, such as a bridge.

It is an object of the present invention to improve known methods for the exploration of dental models.

This objective is solved with a method according to claim 1.

Optical scanning equipment is provided with which a model can be scanned in a scanning area. The width of the scanning area can be between 5 mm and 100 mm. In this range there is a good resolution of the data together with a sufficiently large model scan area. The lower limit can also be 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75mm. The upper limit can also be 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 mm.

With the scan kit, you can prepare a scan that spans multiple model parts. In this way, the relative situation of the model parts to each other can be determined. Such a scan can also be called a panoramic scan. In this case, the model parts are inserted into the model part holder of the segmented dental model.

In addition to that, a second scan (single scan) or several of the same ones that scan an individual model part can be prepared. This scan is preferably performed on a model part that has been removed from the model part holder of the segmented dental model. In this case, the model part is held independently of the model part holder of the segmented dental model. However, the model part can also be inserted into the model part holder. However, in this case, the adjacent model parts must be removed, to improve the optical accessibility to the model part.

The data from the first scan and the second scan can have different resolutions. Panoramic scan data may, for example, be somewhat more inaccurate than individual scan data. However, they can also have the same resolution or a higher resolution.

The data from the individual scan will, as a rule, represent the shape of a model part more completely than that from the panoramic scan, as there is no shading by adjacent model parts. Therefore, the single scan is more comprehensive than the panoramic scan.

The first and second data can be saved and processed by a 3D matching equipment to obtain a single data set from the segmented dental model or a section thereof.

The device has a base plate. Preferably, the base plate is essentially flat on the upper side. However, it can also comprise cavities such as grooves, grooves, holes or the like and / or

ES 2 333 262 T3 bolt-like elevations on the upper side. In this way, for example, other elements can be attached to the base plate such as an adapter and / or a holder.

Furthermore, the device comprises a clamping device with which a segmented dental model, a model part or several model parts or combinations thereof can be clamped. The base plate together with the clamping device allows great flexibility in the arrangement of the objects to be scanned with respect to the scan area.

Preferably, the base plate and the clamping device are configured such that the clamping device can be arranged on the base plate in any position. The base plate can also comprise one or more snap kits, into which a bra can be snapped. The base plate can also have elements arranged in a grid that makes it possible to arrange the clamping device in different defined grid positions. The elements (holes, bolts, etc.) are preferably arranged periodically.

Preferably, the base plate is rotatable relative to the scan zone. In this way, different areas of the model can be explored or made accessible for exploration. The base plate can be in the shape of a turntable. In this way, it can fit well into a circular opening of an environment plate.

Preferably, the base plate can be driven in a straight line. In this way, different areas can be made accessible for exploration. Preferably, straight-line drivability is provided in one or two directions (preferably perpendicular to each other).

Preferably the base plate is height adjustable. In this way, on the one hand, it can be achieved that the object to be scanned is located at a suitable separation to the optical scanning equipment. This can be relevant, for example, for the focusing of a lighting optic or a recording optic. On the other hand, the height of the base plate also modifies the relationship between the pivot point of the base plate and the scanning area on the base plate (see below).

The possibility of clamping the clamping device by magnetic force on the base plate is preferred. As a general rule, the force is high enough to prevent accidental displacement of the clamping device, for example during a scan. Such a fastening of the clamping device can also be easily released without tools. In addition to that, it allows an arrangement of the clamping device on the base plate in any location and orientation.

The holding device can hold the object to be scanned preferably at different heights on the base plate. For this, different clamping devices with different heights or clamping devices that can be graduated in height can be provided. In this way, the separation between the object to be scanned and the scanning equipment and also the relationship between the base plate and the scanning area can be modified (see below).

From DE 103 04111A1 a phase shift scanning method is known which can be used in this case. Reference is made in its entirety to this document and the scanning method described therein as well as a correspondingly configured device and its description is included in this document. Laser line scanning methods are also known, in which a laser line is directed onto an object and with a triangulation angle the object can be detected and the height profile deduced from the reproduction of the laser line. .

The scan area of ​​a phase shift scan can be square or rectangular (viewed from above on the base plate). The length of the edges of the square or the length of the edges of each of the sides of the rectangle can be 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75 , 80, 85, 90, 95, 100, 110, 120 or 130 mm or within a range formed by these values. All possible combinations from the preceding values ​​are possible.

Advantageously, the device has a transfer device, with which an axis of rotation can be translated with respect to the exploration zone. In this way, on the one hand, an axis of rotation can be created outside the scanning zone and inside the scanning zone. The former makes it possible to arrange the center of a dental arch on or next to the axis of rotation while the dental arch itself is in the exploration area. In the second case, a model part center can be arranged on or next to the axis of rotation, where this model part center is located in the scanning zone.

One or more linear displacement tables or an adapter can be provided for the axis movement. The axis of rotation can also be tilted additionally or alternatively, since in this way other viewing angles of a scanning device are made possible on a dental model to be scanned. The adapter has a rotary element which is mechanically coupled by the adapter to the base plate, so that during a rotation of the base plate, the rotary element is turned. The rotary element can then have a rotary axis translated in comparison with the rotational axis of the base plate.

IS 2 333 262 T3

In the event that the scanning zone defines a plane in which the scanning zone lies, a translation of the axis of rotation along or parallel to the plane is particularly advantageous. This can also be done independently of a possible translation component in a direction transverse to the plane.

In addition to that, an adjustment aid is advantageous. This roughly predefines where a segmented dental model or part of a model should be placed. This affects both the height and the position in the surface plane of the base plate relative to the base plate. Different adjustment aids can also be provided for height and position.

The height adjustment aid can be located, for example, on the base plate or a plate surrounding the base plate and indicate with a mark the preferred height or with several marks a possible range of heights. In the case of the model, for example, the gingiva limit or the preparation limit or the upper edge of the model can be arranged with respect to the height adjustment aid.

The adjustment aid for the position may comprise a transparent glass, on which are indicated marks, such as lines or dots, which indicate certain reference points of the model. The glass can be arranged on the base plate and, for adjustment, the pattern can be seen through the glass with the markings.

The adjusting aid may also comprise a camera which is arranged in a defined location with respect to the scanning zone and which has a view towards the base plate. In an image representation of the camera image, information such as, for example, lines or arrows can be indicated with which necessary corrections of the positioning of the model on the base plate are indicated. For example, a theoretical position can be represented together with the actual position. The theoretical position can also be indicated by schematic lines.

A device for the exploration of an additional dental model has a holding device with which a segmented dental model can be explored.

For the production of dental prostheses such as, for example, bridges or the like, it is usually necessary to detect both the relative arrangement of, for example, two adjacent elements (for example, two teeth), however, simultaneously also detect the shape of each individual tooth. However, due to shading effects, it is difficult to detect well the shape of a tooth around its perimeter, when both teeth are arranged side by side. However, a detection with the teeth next to each other is necessary to detect the relative arrangement of the two teeth next to each other.

It is therefore advantageous if, on the one hand, a scan is carried out when the different teeth are predefined in their position relative to each other (panoramic scan) and then a scan of each individual tooth, in order to correctly detect their shape around its perimeter (individual scan).

In the case of the device only one clamping device is provided, with which, however, several teeth arranged in their relative position to each other can be clamped and, however, at the same time individual teeth can also be clamped, without stopping this requires two different clamping devices.

When referring to a tooth or teeth above or below, these explanations naturally also apply correspondingly to dental prostheses, residual tooth areas, gingival areas or combinations thereof, such as, for example, a tooth and a dental prosthesis. that is arranged adjacent to it. Dental prostheses can be, for example, implants, implant posts, bridges, inlays, overlays or the like.

Advantageously, the holding device comprises a molding mass for holding, such as, for example, a plastic mass or wax. The dental model pins can be well sunk into the plastic mass as used in segmented dental models, to thereby achieve a dental model. In addition to that, it is also possible to superimpose a larger model part on a plastic mass (also without having bolts), where the moldable mass preferably has a sufficient adhesive effect to hold this model. The mouldable mass is advantageously arranged in a container or on a plate. This plate or this container can be arranged on the base plate 7 or be the base plate. In the first case, a magnet can be provided for clamping the clamping device on the base plate.

The clamping device described above can be advantageous independently of the device with a base plate. However, it can also be used in combination with it. In this case, then, for example, the holding device with the mouldable mass can be placed on the base plate.

In another embodiment of a device for the exploration of dental models, the device has a loading facility. With the charging installation, several dental models and / or individual parts of a dental model can be worn consecutively or simultaneously to a bra. This bra can be, by way of example, a bra made of a mouldable mass as described above.

The loading system advantageously comprises one or more cameras, with which the position of the dental models and / or parts of a dental model, such as the part of a dental model, can be detected.

ES 2 333 262 T3 segmented. Based on the images recorded by the cameras, it can be determined where the parts to be recorded are located.

For the insertion of dental models or parts of a dental model in the holder a robot arm is advantageously provided. With the cameras and the robot arm, a fully automatic device loading for dental model exploration can be performed. Other possibilities for charging are also possible. By way of example, dental models can also be transported with a conveyor belt to the device for examination. Slides or the like are also possible for the movement of dental models.

The following steps are envisaged in a method for the exploration of a segmented dental model. The different model parts of a segmented dental model are held by a model part holder and scanned in this configuration. In a further stage, one or more model parts are scanned, where in this case each model part can be detected independently of the other model parts. The two stages can be done in any order.

The use of a segmented dental model with individual model parts and a model holder has the advantage that the model parts that are held by the model holder can be scanned immediately afterwards and the individual model parts. Therefore, a segmentation of a one-piece dental model between two examination procedures is not necessary, so that the examination can be performed easily and quickly.

In an advantageous embodiment of the method both the inner side and the outer side of the segmented dental model are scanned. In this way, a good all-round view is given on the dental model. The data obtained from the individual model parts can be put together by data processing (matching) with the data that has been obtained from the model parts inserted into the model part holder. For this, the examination of the external side or the internal side of a segmented dental model is sufficient in itself. However, the use of data affecting both the external and internal sides of the segmented dental model gives an improved total representation of the dental model and also an improved matching result.

The exploration of the segmented dental model in the aforementioned first stage can be carried out by the exploration of several individual areas respectively extending over several tooth sites. In this way, by way of example, it is possible to explore a model that represents a total upper or lower jaw with 3, 4, 5 or 6 individual zones on the external side and a corresponding or different number on the internal side.

Between the exploration of the different individual zones, the model can be moved and / or rotated to achieve good access to the zones respectively to be explored.

Each of the devices that have been described can comprise a darkening device that shades and protects the objects to be scanned from light from the environment. This improves optical scanning.

Each of the devices can have an internet connection. In this way, internet updates are possible. In this way, remote maintenance of the device is also simplified or made possible.

In addition to that, each device can comprise an additional camera that can reproduce different parts of the device and / or models. The camera can be used for remote maintenance. An existing camera can also be used for this (eg from the adjustment or from the imaging system in the loading facility). Preferably, the camera records 2D images.

German patent DE10 2005 016 233 dated 19.10.2006 of the same applicant describes a method and a device for data transmission in the production of dental prostheses. The characteristics specified in that document of a scanning device for obtaining data sets can be provided alone or in any combination in the device of this application. Particularly, the remote data transmission means can be provided with the camera for the transmission of digital image data and advantageous embodiments thereof from the German application on the device of this application. The methods described in the German application can also be performed with the device of this application or corresponding means can be provided for this.

Advantageous embodiments of the device of the method are explained by means of the figures. It shows:

In Figure 1, schematic representations of a device for the exploration of dental models,

In Figure 2, schematic representations of the top view on a base plate and side views with a segmented dental model and a model part,

In Figure 3, different drawings of the adapter cut,

In Figure 4, different schematic representations of a bra,

IS 2 333 262 T3

In Figure 5, different states of the method during the performance of the method,

In Figure 6, a schematic representation of a loading equipment.

In Figure 1a a device 1 for the exploration of dental models is shown in a three-dimensional schematic representation. The apparatus has a bottom plate 5, on which a second bottom plate 4 is arranged obliquely on a support 6. The bottom plate 4 is arranged at an angle of 20 ° to 80 ° or 35 to 60 °, preferably about 45 ° to the bottom plate 5. The bottom plate 4 carries an optical scanning system 2, which can scan models with a strip-shaped scanning zone 3. The fringe-shaped scanning zone 3 is also located at an angle of 20 ° to 80 °, preferably 35 ° to 60 °, even more preferably, approximately 45 ° or more or less than 45 ° to the bottom plate 5 or base plate 7.

The path of the laser light for illumination of the model with the laser line defines the scan zone 3 during the laser line scan.

During a laser line scan, a plane is defined by the light from the laser line. During a phase shift scan, a plane is defined by the center of the illumination light. As a rule, the viewing direction of the observation camera of the phase shift method is also located in this plane. The viewing direction includes with the base plate surface preferably an angle of 20 ° to 80 °. In this case, the viewing direction defines the scan area. You can also change the lighting and the camera. In this case, the scan area is defined by lighting. Then the central (optical) axis of the illumination has an angle of 20 ° to 80 ° with the surface of the base plate. Angles can also be between 35 ° and 60 ° or about 45 ° or above or below 45 °.

The model can be arranged on a base plate 7. The base plate 7 is designed as a turntable and has a rotary axis 8, whereby the turntable 7 can be turned in both directions or also only in one direction around the axis. 8.

The axis 8 can be displaced in the direction 9 and 10. For this, the bottom plate 5 can have corresponding recesses, so that it is more of a frame. Direction 9 is located in a direction transverse to the plane defined by scanning strip 3. Direction 10 is located in this plane and perpendicular to direction 9. By moving the axis 8 in the direction 9, a pattern can be moved on the turntable 7 in the direction transverse to the strip 3. In this way, an area of ​​the pattern can be scanned. By moving axis 8 in direction 10, the area that is scanned during movement in direction 9 can be changed.

Figure 1b shows a view on the device of Figure 1a, parallel to the bottom plates 4 and 5. Figure 1c shows a view on the device of Figure 1a along direction 10.

Between the surface of the base plate 7 and the scanning zone 3 an angle alpha is included (Figures 1b and 1d). This comprises, for example, between 20 ° and 80 °, 35 ° to 60 ° or, preferably, about 45 °. This angle allows a particularly good representation and exploration of the preparation boundary. At that location, a particularly accurate scan of the model for well-fitting dentures is desirable.

As can be seen in Figure 1b, the relationship between the pivot point of the model and the scanning area 3 can be modified by a modification of the height of the base plate 7 or of the model 11 on the base plate 7. In the case represented in Figure 1b, an area of ​​the model is explored outside the pivot point of the model. If the model were arranged lower down, the scanning zone 3 would scan an area on the base plate 7 that is located more towards the center, which is located closer to or next to the axis of rotation 8.

On the base plate 7 a holder H is arranged which holds a segmented dental model 11. The holder H may be, for example, plastic mass.

While an embodiment is shown in Figure 1 in which the turntable 7 is fixedly connected to the rotary axis 8 and the rotary axis is displaced in the direction 9 and 10 with, for example, tables of X, Y, other configurations are also conceivable. By way of example, a turning device can be detachably connected to the turntable 7. By way of example, for this, an electromagnet can be turned on or off below the turntable 7 on axis 8 or moved away from or moved towards the turntable, to increase the magnetic coupling. For this, a permanent magnet can also be provided. A suction device can also be provided which fixes the negative pressure turntable in different positions for rotation.

To move the rotary axis, the connection between the rotary axis and the turntable is released, the rotary axis is shifted (in direction 9 or 10) and then the connection between the rotary axis and the turntable is restored. turntable elsewhere. The junction can be produced with the electromagnet, a permanent magnet or a suction device or the like. The turntable 7, as long as it is not held by the axis of rotation 8, can rest on a support having an opening through which the axis of rotation 8 can pass, which, however, supports the outer periphery of the Turntable 7. With this configuration, rotations of the turntable 7 around other axes than the center of the turntable 7 are possible.

IS 2 333 262 T3

In Figure 2a a dental model 14 is shown on a turntable 7. The dental model 14 has two essentially linear parts 15, 16 which are connected with a circular line shaped part 17 (dental arch). The center of the circular line-shaped piece 17 is referenced 12. Virtually all human dentures have such a configuration. The transition between the linear pieces 15, 16 and the circular arc-shaped piece 17 is marked by the dashed lines 18 and 19.

In order to scan the circular arc-shaped part 17, it is advantageous to rotate the turntable 7 around the center 12. The area that can be detected by the fringe-shaped scanning area 3 is specified by the line 13 '. It has a width B, which is measured in the plane of the base plate 7 and ranges from 5 mm to 80 mm. By rotating the turntable 7, the area of ​​the dental model 14 that lies between the discontinuous lines 18,19 can be scanned. In this case, it must be considered that the center 12 is located outside the area 13 'that can be detected by the scanning area. The axis of rotation of the turntable 7 is located as close as possible to or above the center 12 of the circular line-shaped part 17. The gap between 12 and the center of the scan area B is called A.

The exploration can be carried out both during the rotation of the turntable 7 or also by a displacement (preferably linear) in the direction transverse to the exploration zone (in Figure 2a upwards or downwards). In the latter case, the part 17 can be scanned by individual zone scanning, where the data from the individual zones can be joined together by a respective overlap of adjacent zones with a matching method. Between the exploration of these individual areas, the turntable is rotated around its axis of rotation a little more, to explore the next individual area and thus have gradually scanned the entire part 17. This composite data forms the panoramic scan data.

In the case represented in Figure 2b, a model 20 of an individual tooth 21 is arranged on the turntable 7. The tip of the tooth is referenced 12. To explore the model of tooth 21 well and from all sides, the tooth must be able to rotate with respect to the scan area. For this, a turn around point 12 is advantageous. However, in this case, it is reasonable for the scanning area 13 "to be located next to the desired axis of rotation 12.

By translating the axis of rotation of the turntable with respect to the scanning zone it is possible to achieve both a configuration (between the axis of rotation and the scanning zone) as shown in Figure 2a and a configuration as shown. in Figure 2b. The corresponding is also possible with a height adjustment of the base plate and / or a clamping device.

In Figure 2c the case in which a panoramic scan of the segmented dental model is to be performed is represented in the upper part. The axis of rotation 8 is located approximately next to the center 12 of the dental arch 17. The examination zone is located next to the dental arch. In Figure 2c a model part of an individual tooth is arranged in the lower part next to the axis of rotation 8. Therefore, it can be rotated without leaving the scanning area. The axis of rotation 8 has to be translated for this in comparison with Figure 2c in the upper part in the module V. V comprises, for example, 22.5 mm.

By moving the base plate 7 below the scanning zone 13 in a direction transverse to the scanning zone 13, a fringe-shaped zone on the base plate can be scanned. This is provided with the reference S in Figure 2d. As can be seen, the dental arch can be explored quite well. By turning around the dental arch center 12, the straight line portion 16 (or at least its outer side) can be fully brought into the strip S and preferably scanned at once.

In the event that it is desired to explore both the external area of ​​the model 14 and the internal area, a translation of the turntable is also advantageous. In Figure 2f and Figure 2g the turntable 7 is shown in sectional view. Model 14 has been rotated compared to Figure 2a approximately 90 ° clockwise. The external area of ​​the dental model is indicated by the reference 22a and the internal area by the reference 22b. The outer zone 22a is advantageously scanned from the outside and the inner zone, from the inside, to avoid shading. To achieve the same, preferably, the rotary table 7 or its axis of rotation can be translated. In this way, as shown in Figure 2f, the outer zone 22a of the part 16 can be explored from the outside and the inner zone 22b of the part 15 from the inside (see Figure 2g). In Figure 2g the rotary table 7 has been moved with the model compared to Figure 2f. In this case, the displacement is greater than in Figure 2c. The necessary offset can be up to 100 mm.

The transfer can also be performed in such a way that the base plate is moved to a loading position where insertion and removal of a model are easily possible.

The different transfer teams can be given respectively in pairs or all three together by the same transfer team. However, each of the transfer teams can also be independent of the others. They can also be superimposed respectively (example: two linear tables mounted in such a way that one can move the other and the respective direction of movement is respectively the same (or also different)).

In Figures 3a and 3b, adapters 23 are shown, with which the axis of rotation can be translated with respect to the scanning zone. Figure 3a shows the turntable 7 with the rotary axis 30. For the examination of a small model part, such as a single tooth, a rotary element is provided.

IS 2 333 262 T3

26. This can be correspondingly rotatably accommodated in a cover 24. In addition, the adapter has an element 25 that can be connected to the turntable with a non-positive connection. This can also occur by the corresponding shaping of the turntable and element 25, for example by bolts and holes or grooves and projections or the like, as well as, for example, by magnetic force between element 25 and the turntable 7.

The rotary element 26 and the element 25 are connected to each other with a (flexible) shaft 27, which transmits the rotational movement of the element 25 onto the rotary element 26. Instead of a shaft 27, toothed wheels are also possible on a corresponding gear arrangement, toothed belts or the like for the transmission of the rotational movement. The element 25 is rotated by the rotation of the turntable itself 7. A dental model can be arranged on the rotating element. For this, a mouldable mass (eg plastic mass) can be provided on or in the turning element or in a container fixed thereon.

The cover 24 of the adapter 23 is fixed on the outside of the turntable 7 in a stationary manner.

As can be seen in Figure 3a, the axis of the relevant rotary movement is translated from the axis of rotation 30 of the turntable 7 at the gap 28 towards the axis of rotation 29 of the rotary element 26. The translation is carried out in the plane defined by scan zone 3.

Compared to Figure 3a, in Figure 3b, the turning element 26 'is inclined. Therefore, the axis of rotation 29 'of the rotating element 26' has an angle 31 with respect to the axis of rotation 30. This angle preferably comprises between 5 ° and 40 °, for example, 15 ° to 25 °, preferably about 20 °. Preferably, the angle 31 should be located between the angle that the scanning zone 3 adopts with a vertical of the bottom plate 5 or a vertical of the turntable 7.

In Figure 4a a turntable 7 is shown with a clamping device 33 arranged thereon. The holding device 33 comprises a mouldable mass, such as, for example, plastic mass. On this plastic mass a dental model can be arranged by superposition and can be held by the plastic mass. Due to the friction of adherence between the dental model and the molding composition 33, a sufficient holding of the model is provided.

The mouldable dough is placed in a cylindrical shape on the turntable. However, the turntable can also comprise a container in which the moldable mass is arranged.

In this document, the model in an illustrative embodiment is a segmented dental model. Provided therein is a model part holder 34, into which individual model parts corresponding to one or more tooth sites are inserted, with bolts or other means. In this document, the different model parts are illustratively referenced 35 to 38. These model parts 35 to 38 are individually removable from the model part holder 34. They can be bolted into the mouldable mass 33. In this way, they are held, albeit loosely, yet sufficiently, to add to the scanning procedure. In this case, an optical scan is preferred, since in this case no force is exerted on the model parts.

Thus, with the mouldable mass 33 it is possible to hold both a total segmented dental model and individual model parts thereof, so that only a single holder is needed without the need for two respectively different holders.

A mask, for example made of paper or metal, can be permanently or temporarily arranged on the mouldable mass, with which the approximate positions of the individual parts are predefined.

Figure 5a shows a segmented dental model that is located in the exploration zone 3. By rotating the segmented dental model, the relative position of the different model parts to each other in the model can be detected. The model shown is a segmented dental model with a model 34 part holder.

With the configuration shown in Figure 5a, only the outer side of the teeth can be explored. To explore the inner side as well, the segmented dental model has to be moved accordingly.

An examination of both the external sides of the dental casts and also the internal sides is particularly advantageous.

After the entire dental model has been optically scanned, the model parts of the segmented dental model are removed from the model part holder 34. They are then individually scanned as shown in Figure 5b. In this case, the dental model 38 can be scanned during its rotation, to scan all sides of the dental model in such a way, or the dental model can be displaced linearly through the exploration zone 3 in the shape of a swath and rotate between individual travel procedures. Then, also due to this, it is possible, by digital matching of the data obtained, to achieve a digital reproduction of the dental model 38 over its entire perimeter.

IS 2 333 262 T3

Afterwards, the data obtained in the stage represented in Figure 5b can be digitally processed with the data obtained in the stage represented in Figure 5A to achieve in such a way with a matching method a reproduction of the dental model. as true to detail as possible digitally.

Figure 6 shows a dental model exploration device featuring a loading facility. The loading installation comprises a chamber 41 with which dental models 34a to 34e respectively can be detected individually or together. The dental models are stored on a transport path 42 which can be configured as a chute or conveyor belt or the like. With a robot arm 40, the individual dental models 34a to 34e can be inserted into the device for dental model exploration. In this case, the robot arm 40 can be moved in the direction 43 up and down and in the direction 44 to the right and left. Movement transverse to the drawing plane is also possible, for maximum flexibility.

The robot arm can grip a dental model 34a with claw arms 45a and 45b. In this way, it is possible to insert or extract the dental model 34a into and out of the device for exploration. The robot arm is preferably configured such that it can also extract individual model parts of a segmented dental model from a model part holder. Thus, then, individual model parts can also be brought into an automated scan procedure.

Advantageously, the device is configured in such a way that, with the robot arm or other mechanical automated handling element, all the models or model parts can be brought to the different examination procedures without human intervention.