WO2010136517A1

WO2010136517A1 - Imaging system for producing a 3-d data set and method for the operation thereof

Info

Publication number: WO2010136517A1
Application number: PCT/EP2010/057308
Authority: WO
Inventors: Volker Rasche; Erich Hell; Johannes Ulrici
Original assignee: Sirona Dental Systems Gmbh
Priority date: 2009-05-28
Filing date: 2010-05-27
Publication date: 2010-12-02
Also published as: DE102009027356A1

Abstract

The invention relates to an imaging system (6) for producing a 3-D data set of at least one part of a jaw, comprising an image generating unit (11) for three-dimensionally measuring an object located in an examination volume, wherein a measuring device (10) for determining the position of the maxilla (37) and the mandible (38) relative to each other at least in one direction of mobility is provided. Furthermore, the data produced using the image generating unit (11) are assigned to the position of the maxilla (37) and the mandible (37) relative to each other. The invention further relates to a method for operating the imaging system (6) according to the invention.

Description

description

Imaging system for generating a 3D data set and method for its operation

Technical Field The invention relates to an imaging system for generating a 3D data set of at least a part of a jaw, and to a method for its operation.

State of the art

In principle, modern imaging systems of the present generation in medicine, such as X-ray fluoroscopy (XR), computed tomography (CT), volume CT (VCT), ultrasound (U / S) or magnetic resonance imaging (MRI), have the The following are referred to as a system, scanner or apparatus, the ability to acquire the image data or recordings with an external signal such as to synchronize an electrocardiogram signal (ECG signal). For this reason, almost all systems have the ability to generate an external signal, e.g. in the form of an ECG signal into the scanner. An MR tomograph is known from DE 10 2006 018 413 A1, which comprises inter alia a unit for determining the anatomical area to be examined in the examination subject, a unit for combining a plurality of MRT images recorded with different measurement parameters, a memory unit and a recording unit.

From DE 10 2006 038 744 Al a bite device for positioning a patient in an X-ray receiving device is known, which may consist of an upper bite plate for the upper jaw and a lower bite plate for the lower jaw, which are connected via a fastening part with an X-ray receiving device. The invention has for its object to provide an imaging system and a method for two- or three-dimensional measurement of a temporomandibular joint with the active involvement of the musculoskeletal system. Presentation of the invention

An imaging system according to the invention for generating a 3D data set of at least one part of a jaw has an image generation unit for the three-dimensional measurement of an object located in an examination volume. Furthermore, a measuring apparatus is provided, which generates at least one signal during a recording or a recording series of the image generation unit, which corresponds to the relative position of the upper jaw and the lower jaw to each other in at least one direction of mobility and there is an assignment of the images generated with the image generating unit to the at least one signal.

As a result, during a recording of image data of the object located in the examination volume with the image generation unit, the respective position of the

Temporomandibular joint, or the position of the upper jaw and the lower jaw to each other by means of the measuring apparatus are determined and assigned to the corresponding data for the 3D data set. Advantageously, a memory is provided for all signals of the measuring apparatus generated during the recording or the recording series of the image generation unit. This makes it possible to perform the assignment of the images generated with the image forming unit to the signals of the measuring apparatus only after completion of the recording or the series of pictures. Advantageously, the measuring apparatus has a camera which records two-dimensional images of at least a part of the head of a patient, from which the signal corresponding to at least one of the relative positions of the upper jaw and the lower jaw can be generated.

As a result, the position of the jaws relative to one another, that is to say the opening angle of the jaw, can be measured in a simple manner simultaneously with the images of the image-forming unit.

Advantageously, the measuring apparatus has at least one transmitter which can be connected by means of a holder to the upper jaw or the lower jaw and that at least two receivers are provided, which detect a signal transmitted by the at least one transmitter in a spatially resolved manner.

This sender and receiver system provides an easy way to determine the location of a point in space. As a transmitter, which can also be referred to as an active marker, for example, an LED can be used and as a receiver, for example, cameras can be used. Since the upper jaw, in contrast to the lower jaw, is rigidly connected to the rest of the head, it is of course also possible to attach a transmitter to another point on the head except for the lower jaw, instead of on the upper jaw. Advantageously, a fixation for the opposite jaw or at least a second transmitter is provided, wherein the second transmitter is connectable by means of a holder with the opposing jaw and the signal is distinguishable from that of the first transmitter. This allows the position of the maxilla and mandible, ie the relative position of the maxilla and mandible - A - and thus also determines the opening angle of the temporomandibular joint and signals are generated, which correspond to the relative position and / or the opening angle.

As a fixation for the upper jaw, for example, a bite can be provided. In order to fix the maxilla, it is also possible to fix the head of the patient, for example by means of a forehead support or by means of ear plugs, since the maxilla is rigidly connected to the rest of the head, except the lower jaw. As a fixation for the lower jaw, for example, serve a chin rest.

Advantageously, the measuring apparatus has at least one receiver and at least one marker visible by the receiver, wherein at least one marker can be connected to the upper jaw or the lower jaw by means of a holder and the receiver determines the orientation of the marker in at least two dimensions in a spatially resolved manner.

Thereby, the position of the marker and thus the position of the jaw, on which the marker is held, can be determined in space in a simple manner. A marker may be an anatomical and / or non-anatomical marker, such as a body having a specific geometry that allows the location of the marker to be determined based on the orientation of the geometry on at least one two-dimensional image taken from a known position determine. Such a marker can also be called a passive marker. In contrast, a transmitter, such as an LED, may be referred to as an active marker. For example, a camera permanently installed in the room can be used as the receiver, so that the direction from which the camera takes a picture of the marker is known. Again, it is possible to attach a marker not on the upper jaw, but at a different point of the head except the lower jaw, as the upper jaw is rigidly connected to the rest of the head. Advantageously, a fixation for the opposite jaw or at least a second marker is provided, wherein the second marker is connectable by means of a holder with the opposing jaw and distinguishable from the first marker.

As a result, the relative position of the upper jaw and lower jaw and thus also the opening angle of the temporomandibular joint can be determined and signals can be generated which correspond to the relative position and / or the opening angle.

As a fixation for the lower jaw, a chin rest can also be used here. For fixation of the upper jaw can also be used a bite or it can instead of the fixation for the upper jaw a fixation for the head, for example by means of forehead support or Ohroliven, provided because the upper jaw is rigidly connected to the rest of the head, except the lower jaw , Advantageously, the measuring apparatus has a device for generating a homogeneous magnetic field and at least one gradient coil system for generating a gradient field and at least one coil acting as a receiving coil is provided, which can be connected directly or by means of a holder with the upper jaw or with the lower jaw.

If the imaging unit is an MRI apparatus, the apparatus for generating a homogeneous magnetic field and at least one gradient coil system are already present. Therefore, the provision of a small coil for determining position via resonant frequency measurement is Within the magnetic fields, a very simple and inexpensive embodiment of the measuring apparatus according to the invention. It should be noted that the coil must be made sufficiently small in size, so that they miss the field as local as possible, thereby allowing a position within the gradient field. Again, it is possible to attach a coil to another part of the head except the lower jaw instead of the upper jaw, because the upper jaw is rigidly connected to the rest of the head.

Advantageously, a fixation for the opposite jaw or at least a second coil is provided, wherein the second coil is attachable to the opposing jaw.

As a result, the relative position of the upper jaw and lower jaw and thus also the opening angle of the temporomandibular joint can be determined and signals can be generated which correspond to the relative position and / or the opening angle. Again, it is possible to provide a bite for fixation of the upper jaw or instead of a fixation for the upper jaw a fixation for the head except the lower jaw, for example by means of a forehead support or by Ohroliven provide, since the upper jaw rigid with the rest of the head connected is. As a fixation for the lower jaw, a chin rest can also be used here. Advantageously, the measuring apparatus has at least one

Gradientenspulensystem for generating a gradient field and at least one magnetic field sensor is provided, which is connectable directly or by means of a holder with the upper jaw or lower jaw. By means of the magnetic field sensor, the gradient field can be measured directly and thus a position determination can be made. It is also possible here a magnetic field sensor instead of the upper jaw elsewhere in the head except the lower jaw because the upper jaw is rigidly connected to the rest of the head.

Advantageously, a fixation for the opposite jaw or at least a second magnetic field sensor is provided, wherein the second magnetic field sensor is attachable to the opposing jaw.

As a result, the relative position of the upper jaw and lower jaw and thus also the opening angle of the jaw joint can be determined and signals can be generated which correspond to the relative position and / or the opening angle. Again, a bite may be used to fix the upper jaw, or it may be possible to provide fixation of the head instead of fixation of the upper jaw, for example by means of a forehead rest or ear irons, since the upper jaw is firmly connected to the rest of the head except for the lower jaw is.

Advantageously, the measuring apparatus is designed as a biting apparatus, which comprises an uptake part for the upper jaw and an uptake part for the lower jaw. The uptake parts are at least partially insertable into a patient's mouth and follow an alignment and a movement of the upper jaw and the lower jaw. Furthermore, the upstand parts are movably connected to one another via at least one joint and / or at least one guide and the at least one sensor measures the position of the upstand parts relative to one another in at least one direction of mobility, so that an association of the recordings made with the image generation unit the respective at least one angle and / or the respective at least one displacement between the toe parts can take place. The up-cut parts are devices which can be connected to the upper jaw or the lower jaw so as to follow a movement. For this purpose, the up-cut parts can for example be attached to one or more teeth or, for example, a means can be provided which holds the up-cut parts to a part of the jaw or one or more teeth. By providing a plurality of joints and / or guides which connect the upstand parts, it is also possible to measure and display more complex movements of the jaw than just the one-dimensional opening.

Advantageously, the upstand parts are designed as rails. As a result, the upstand parts can be guided and / or fastened to a plurality of teeth of the upper jaw or of the lower jaw, which largely prevents a movement of the upstand parts in relation to the teeth. This makes it possible to ensure that only the movement of the temporomandibular joint is measured, and not additional movements of the uptake parts in relation to the upper jaw and / or the lower jaw. Advantageously, the upstand parts are respectively attached to teeth of the upper jaw or of the lower jaw. As a result, the position of the upstand parts relative to the upper jaw or lower jaw can also be fixed during a movement of the temporomandibular joint. Advantageously, the biting apparatus has a return element. In this way, in the absence of external force, the upstand parts are again brought into a fixed, spaced-apart position, which ensures that the upstand parts follow the upper jaw or the lower jaw when the patient opens his mouth, without the uptake parts at one or the other several teeth or the jaw must be attached. Advantageously, the at least one joint and / or the at least one guide, as well as the at least one sensor of the biting apparatus are located outside the patient's mouth and are connected to the toe parts. This allows the part of the bite apparatus, which the patient takes in the mouth, to be kept as small as possible in its outer dimensions.

Advantageously, the at least one joint of the biting apparatus is movable about at least one hinge axis orthogonal to a longitudinal axis of the biting apparatus, so that the upstand parts can be brought to one another at at least one angle, wherein at least one angle sensor is provided for signal detection of the at least one angle.

As a result, for example, the mouthpieces can follow the upper jaw or the lower jaw during opening of the mouth, and the angle of the temporomandibular joint can be determined continuously during the movement.

There may also be provided a joint between the toe parts which allows the toe parts to move one way around the upper jaw relative to the lower jaw

Follow axis orthogonal to the occlusal plane, and to measure the corresponding angle between the upper jaw and the lower jaw by means of an angle sensor. Advantageously, the upstand parts of the biting apparatus are displaceable along a guide in the direction of a longitudinal axis of the biting apparatus, wherein a position sensor is provided for signal detection of the displacement.

This allows the Aufbissteile the upper jaw or the lower jaw even with a movement of the lower jaw against the upper jaw in the direction of the longitudinal axis of the Aufbis- sapparat and this shift can be measured.

Advantageously, the upstand parts are slidable via a guide in the direction transverse to a longitudinal axis of the biting apparatus, a position sensor being provided for signal detection of the displacement. As a result, a movement of the lower jaw relative to the upper jaw transversely to the longitudinal axis of the bite apparatus can be measured.

The combination of several joints with different joint axes and / or several guides makes it possible in particular to measure more complex movements of the temporomandibular joint.

Advantageously, the biting apparatus has at least one locking means which prevents at least one displacement or tilting of the upstand parts against one another or at least detects an angle. As a result, the mobility of the jaw parts can be limited to one another, so that a measurement of a movement of the jaw can be restricted to essential directions of movement.

Advantageously, a plurality of locking means are provided in each case for at least one displacement and / or for at least one angle and can be used independently of each other. As a result, the mobility of the biting apparatus can be limited to the directions of movement that are to be measured.

Advantageously, the imaging unit is a magnetic resonance imaging apparatus, in particular a whole body tomograph or a head tomograph. As a result, an SD data set of the measuring volume without radiation exposure can be generated. Advantageously, the imaging unit is a computed tomography apparatus. This allows short recording times and a very good representation of the bony structures. Advantageously, the image generation unit is a sonography apparatus. As a result, a cost-effective implementation of an imaging system with short recording times is possible.

Advantageously, the at least one signal of the measuring apparatus is fed into a computing unit of the imaging system. Thereby, the assignment of the signals of the measuring apparatus to the data recorded with the image generating unit in the arithmetic unit can take place, wherein the arithmetic unit is a unit for data processing, which for example also includes a unit for controlling the imaging system, ie the image generating unit and / or of the measuring apparatus and / or an image processing unit. The arithmetic unit can also be, for example, a direct part of the image generation unit. Advantageously, the measuring apparatus generates at least two signals simultaneously, which are processed in a data processing unit into a single signal and the single signal is fed to a computing unit of the imaging system. As a result, by means of the data processing unit, a signal can be provided which contains the information of a plurality of signals of the measuring apparatus and for which the arithmetic unit of the imaging system has a suitable input, so that an association of the images taken with the imaging system to the respective one of the up-parts to each other and thus to the respective position of the temporomandibular joint can be made. Advantageously, an arithmetic unit with an input for an electrocardiogram signal and a data processing unit for the at least one signal of the measuring apparatus are provided, wherein the data processing unit processes the at least one signal into a single signal and the single signal to the input for an electrocardiogram signal of the arithmetic unit transmitted by the imaging system.

As a result, the input usually present for an electrocardiogram signal of the arithmetic unit of the imaging system can be used. Furthermore, existing algorithms for electrocardiogram analysis can be used.

Advantageously, an arithmetic unit of the imaging system has at least one input for an electrocardiogram signal and the at least one signal of the measuring apparatus is transmitted to the at least one input for an electrocardiogram signal of the arithmetic unit.

If the at least one signal generated by the measuring apparatus is ready for a signal which corresponds to a signal

Electrocardiogram signal is similar, so the signal can be forwarded directly to a commonly available input for an electrocardiogram signal of the arithmetic unit. As a further subject matter, the invention comprises a method for generating a 3D data set of at least a part of a jaw using an imaging system according to the invention and during movement of the temporomandibular joint data for a 3D dataset of at least a part of the jaw with the image generation unit of the imaging system and at the same time the data of the image forming unit at least one signal from the measuring apparatus of the imaging system is repeatedly recorded and assigned to the corresponding data.

As a result, during a measurement of a measurement volume with the image generation unit, the corresponding angular position of the temporomandibular joint can be determined simultaneously.

Advantageously, the at least one signal of the measuring apparatus is processed in a data processing unit into a single signal, which is fed into a computing unit of the imaging system.

As a result, a signal can be generated by means of the data processing unit, which contains the information of the measuring apparatus and for which the arithmetic unit of the imaging system has a suitable input, so that an association of the images taken with the image-forming unit to the respective position of the up-bisected parts to each other and thus to the respective position of the temporomandibular joint can be made. If several signals from the measuring apparatus are processed into a single signal, then the single signal fed in can be used directly or be decomposed into the original multiple signals in the data processing unit of the arithmetic unit.

Advantageously, the at least one signal of the measuring apparatus is fed into a computing unit of the imaging system. As a result, the at least one signal can be fed to the imaging system without prior processing.

Advantageously, the at least one signal of the measuring apparatus is processed in a data processing unit into a single signal, which in an input for a Electrocardiogram signal of the computing unit of the imaging system is fed.

As a result, a normally available input for an electrocardiogram signal of the imaging system can be used.

Advantageously, a maximum or a minimum value of the at least one signal of the measuring apparatus is used as a virtual R-wave of the single signal. As a result, a signal can be generated from the signal of the measuring apparatus, which signal resembles an electrocardiogram signal and can be fed into a corresponding input of the arithmetic unit for the electrocardiogram signals.

Brief description of the drawing

An embodiment of the invention is shown in the drawing. It shows the

Fig. 1 is a schematic drawing of an imaging system according to the invention, the

Fig. 2 shows a measuring apparatus according to the invention, which is designed as a bite apparatus, Fig. 3A, B, a measuring apparatus according to the invention, which is designed as a marker-receiver system, the

Fig. 4 is an active marker designed as a transmitter, the

Fig. 5 is a passive marker, Fig. 6 shows another embodiment of the marker receiver system of FIG. 3, the

Fig. 7A, B two further embodiments of the measuring apparatus according to the invention, the

FIG. 8 shows a generated signal of the measuring device according to the invention. FIG. 9, which is to be fed into the arithmetic unit of the imaging system for synchronization and / or control either directly or after appropriate processing, FIG. 9 shows a signal which can be interpreted as a vector ECG, into which the signal from FIG. 8 can be converted.

embodiment

FIG. 1 shows an imaging system 6 according to the invention with a measuring apparatus 10 embodied as a bite apparatus, an image generation unit 11 and a computing unit for controlling the imaging system, as well as for data storage and data processing.

The bite apparatus comprises an upper jaw bite portion 1 and a lower jaw bite portion 2, which are at least partially insertable into an oral cavity 39 of a patient and follow thereupon the alignment and movement of the jaw 37,38.

The up-cut parts 1, 2 can be designed as bite rails which extend over a plurality of teeth and / or are fastened to a plurality of teeth. In this case, for example, an impression of the upper or lower patient arch produced by means of an impression material can be provided on the respective bite rail for attachment and / or guidance. Alternatively, the upstand parts 1, 2 may also be formed as plates, which are clamped between the anterior teeth.

The up-cut parts 1, 2 are fastened to the upper jaw 37 or to the lower jaw 38 and are connected to a joint 4 and by means of an angle sensor 5 a detection of the angle 3 between the toe parts 1, 2 takes place in the course of the movement of the jaw. The detection of the angle takes place as continuously as possible, so as often as possible, so that as many signals of the measuring apparatus are detected during a recording or recording series with the image forming unit. The Aufbissteile 1, 2 are connected in the case shown in Fig. 1 with a return element 26, which ensures that the Aufbissteile remain during a movement of the jaw always on the upper jaw 37 and the lower jaw 38. The angle sensor 5 is located in the present case outside of the patient's mouth.

The imaging unit 11 of the imaging system 6 may, in particular, be a whole-body tomography apparatus or a head tomography apparatus as known from the prior art.

The measuring device 10, which is partially inserted into the patient's mouth with the shoulder parts 1, 2, enables the representation of a temporomandibular joint in two and three dimensions with the active involvement of the musculoskeletal system. This is done during the continuous opening and closing of the

Patients mouth simultaneously with measured data recorded with the image generating unit 11, a continuous measurement of the angle 3 of the joint 4 with a suitable angle sensor 5 performed. A measured signal S of the angle sensor 5, as shown for example in FIG. 8, is fed via an input of a data processing unit 8 'to the computing unit 28 of the imaging system and together with the simultaneously recorded measurement data of the image generation unit 11 in a memory 7 of the computing unit 28 of the imaging system 6 is stored. On the basis of the signal S of the measuring apparatus 10, an association with the image generating unit 11 of the Imaging system 6 recorded measured data for each angle 3 of the joint 4 between the up parts 1, 2 done.

Alternatively, the signal S can also be further processed in a data processing unit 8 to form a signal S ', which is similar to an electrocardiogram signal. For this purpose, for example, a maximum or a minimum value of an angle 3 or a shift between the up parts 1, 2 of the bit apparatus can be used as the virtual R wave of the respective ECG signal-like signal S '.

This signal S 'can be fed into the arithmetic unit 28 via an ECG input 9 which is normally present in known imaging systems 6 and stored together with the measurement data of the image generation unit 11 recorded simultaneously with the signal S in the memory 7. As a result, existing algorithms of the imaging system 6 can be used for an ECG analysis, and the reconstruction of the images can take place in accordance with the dynamic dynamic repetitive motion reconstruction algorithms integrated in the imaging systems 6, which are used, for example, in cardiac motion.

Each measurement of the imaging unit 11 is assigned by the at least one measurement signal S of the angle sensor 5 of the measuring apparatus 10 a unique position of the at least one joint 4, which corresponds to a specific opening angle of the temporomandibular joint. This assignment makes it possible to combine in the reconstruction in each case all the data which were recorded within an acceptance range around a respective opening angle of the temporomandibular joint, that is to say at a specific position of the joint 4 and to process a 3D data set representing the jaw with the corresponding aperture angle.

When the imaging system 6 is a magnetic resonance imaging system, the time required to acquire data for a 3D data set is in the range of minutes. This makes it difficult to record moving objects with a magnetic resonance tomography system. For repetitive movements, however, this problem can be solved by taking data over several periods of movement and then aggregating the data associated with a particular position within the movement. This allows the measuring apparatus according to the invention. By choosing an acceptance range around the position of the joint 4 and using all the data taken at positions within the acceptance range, one can improve the amount of data to be used to reconstruct a 3D data set. The sharpness and quality of the images can be controlled by a suitable choice of the acceptance range for the variation of the position of the temporomandibular joint, ie of the corresponding signal S of the measuring apparatus 10.

In order to measure the position of the upright part 1 for the upper jaw 37 and the upright part 2 for the lower jaw 38 to each other as accurately as possible, the two upstand parts 1, 2 of the biting apparatus are advantageously connected to each other with a plurality of joints and guide parts movable to each other, with a sensor provided for each degree of freedom is. FIG. 2 shows by way of example a possible connection between the two upstand parts 1, 2 of the measuring apparatus of FIG. 1 designed as a biting apparatus. The Upstroke part 2 is connected via a pivot joint 12 which can be moved about a joint axis pointing in the plane of the drawing, with a guide sleeve 13 which is laterally displaceable along a guide rod 14 and rotatable about the guide rod 14 like a tilting joint.

The guide rod 14 has at both ends a rotary joint 15, 16 with a pointing into the plane of the hinge axis, via which the guide rod 14 is connected to a respective piston rod 17, 18 of a telescopic guide.

In each case a piston guide 19, 20 of the telescopic guides is connected via a respective rotary joint 21, 22 with a pointing into the plane of articulation axis with one end of a guide rod 23, by moving the hinges 15, 16, 21, 22 relative to the guide rod 14 parallel to this , So in the direction of the longitudinal axis Al of the guide rod 14 can be moved. By means of the telescopic guides, the guide rod 21 can also be tilted relative to the longitudinal axis A1 of the guide rod 14. A guide sleeve 24 is arranged around the guide rod 23 and can be aligned along the guide rod 23, ie in the direction of the longitudinal axis A2 of the guide rod 23. The guide sleeve 24 is formed so that it is also rotatable about the longitudinal axis of the guide rod 23. The guide sleeve 24 is connected via a hinge 25 with a pointing into the plane of articulation axis with the Aufbissteil 1.

In order to measure the position of the upstand parts 1, 2 relative to one another, a plurality of angle sensors and a plurality of position sensors are provided in this variant. The position of the hinges 12, 16, 22 and 25 are measured by a respective angle sensor 12 ', 16', 22 'and 25'. One each Position sensor 13 ', 24' measures the position of the guide sleeves 13 and 24 in the direction of the longitudinal axes Al and A2 and a respective position sensor 13 '', 24 '' the orientation of the guide sleeves 13 and 24 around the guide rod around. Further position sensors 19 ', 20' and 25 'measure the position of the pistons 17, 18 the piston guides 19, 20 of the telescopic guides.

Furthermore, a locking means 27 is shown, which fixes the guide sleeve 13 in its position relative to the guide rod 14.

It is also possible to provide further locking means for restricting further degrees of freedom of movement of the upstand parts against each other and for limiting a measurement of the movement of the temporomandibular joint to predetermined directions of movement.

By means of the sensors 12 ', 13', 13 '', 16 ', 19', 20 ', 22', 24 ', 24' 'and 25', each measurement of the imaging unit 11 can correspond to a unique position of the upstand parts 1, 2 relative to one another the several signals S of the sensors are assigned ren.

For this purpose, the plurality of signals S of the various sensors 12 ', 13', 13 '', 16 ', 19', 20 ', 22', 24 ', 24' 'and 25' continuously via an input to the data processing unit 8 'of Imaging system 6 is fed and stored with the simultaneously recorded measurement data of the image forming unit 11 in the memory 7.

Alternatively, the multiple signals S of the multiple sensors 12 ', 13', 13 '', 16 ', 19', 20 ', 22', 24 ', 24''and25' in a data processing unit 8 into a single signal S ' which corresponds to an ECG signal and is input to the imaging system 6 via the ECG input 9. spe i st.

Another variant of a measuring apparatus 10 according to the invention is shown in FIGS. 3A and 3B. The measuring apparatus 10 comprises two transmitters 29, ie active markers whose emitted signals S can be distinguished. The transmitters 29 are each attached by means of a holder 36 to the upper jaw 37 or to the lower jaw 38 of the patient so that they are located outside the oral cavity 39 and follow a movement of the upper or lower jaw 37, 38 At least two receivers 30 designed as cameras are provided, whose orientation is known in space. The receivers 30 designed as cameras simultaneously generate two-dimensional images of the two transmitters 29 from their respective spatial directions, so that the respective position of the transmitters 29 can be determined from two simultaneously recorded images, from which the relative position of the upper jaw 37 to the lower jaw 38 and the Determine the opening angle of the temporomandibular joint and have the signals S corresponding to the relative position and / or the opening angle generated.

As a transmitter 29, for example, a diode 31 may be used which emits a certain wavelength. As a holder 36 may serve, for example, a bite bar 32, with which the transmitter 29 is connected via a bracket 32, as shown in Fig. 4 and which can be fixed to the upper jaw 37 or the lower jaw 38.

In this case, for example, an impression of the upper or lower dental arch of the patient on the bite rail produced by means of an impression compound can be provided for attachment and / or guidance.

Alternatively, however, a plate can be provided which is clamped between the front teeth and at the Transmitter 29 is attached by means of a bracket 32.

Instead of a transmitter 29, it is also possible to use a passive marker 34 which, for example, has a known geometry, as shown in FIG. 5. A receiver 30, for example a camera, is sufficient for determining the position of the marker 34 in space on the basis of the perspective under which this geometry appears on a two-dimensional image recorded by the receiver 30.

The marker 34 could also be metal balls, which are each connected to the upper jaw or the lower jaw, and an MRI apparatus as receiver. On the MRI images, such metal spheres can be recognized as negative contrasts, so that the position of the metal balls on the MRI images can be used to determine the respective position of the upper jaw or of the lower jaw.

As outlined in FIG. 6, instead of two transmitters 29 or two markers 34, which are each connected to the upper jaw 37 or the lower jaw 38, only one transmitter 29 or a marker 34 can be attached to the lower jaw 38 and a fixation for the upper jaw 37 for example in

Shape of a Aufbisses 35 may be provided, which has a fixed known position relative to the reference system of the receiver 30, so the cameras.

But it can also be a chin rest 42 are provided as fixation for the lower jaw and only a transmitter or a marker attached to the upper jaw. A corresponding chin holder 42 is likewise sketched by way of example in FIG.

Two further exemplary embodiments of a measuring apparatus 10 according to the invention which use at least one magnetic field for spatial coding are outlined in FIGS. 7A and 7B. In Fig. 7A, a measuring apparatus 10 is shown, comprising a device 44 for generating a homogeneous magnetic field, a gradient coil system 41 for generating a gradient field in three spatial directions and two trained as receiving coil coils 40, wherein the generated magnetic fields on the zu extend measuring area and the two coils are as small as possible in their dimensions, so that they measure the magnetic fields only very locally. In each case, a coil 40 is attached, for example by means of a holder 36 and / or a bite bar 33 on the upper jaw 37 or on the lower jaw 38, so that they follow their movements respectively.

The patient is positioned with the two coils 40 in the superimposed magnetic fields and by determining the resonance frequency the position of the respective

Coil 40 determines, whereby the position of upper jaw 37 and lower jaw 38 and the opening angle of the jaw can be calculated.

The gradient field can be generated, for example, by means of a plurality of gradient coils, which are arranged around the patient.

It is also possible to provide only one coil 40, which is fastened to the upper jaw 37 or to the lower jaw 38, and furthermore a fixation for the opposing jaw 37, 38 of the patient, for example a bite 35 or a chin support 42, which is the opposing jaw 37, 38 fixed in its position in space, as sketched for example in Fig. 6. This embodiment of an imaging system 6 according to the invention with one or two receiving coils within a homogeneous and a gradient field is suitable if a magnetic resonance tomography apparatus is provided as the image-generating unit 11 Then, since the devices for generating a homogeneous magnetic field and a gradient field, which are used to generate the image data, also for determining the position of the upper and / or lower jaw 37, 38 can be used.

The exemplary embodiment illustrated in FIG. 7B also provides for the use of a magnetic field for position determination. A device 41 for generating a gradient field in three spatial directions is positioned around the patient. Furthermore, two magnetic field sensors 43 are respectively disposed on the lower jaw or the upper jaw. Thus, the position of the respective sensor can be determined via the direct measurement of the local field strength of the gradient field and thus the position of O-jaw 37 and lower jaw 38 and the opening angle of the jaw can be calculated.

It can also be provided only a magnetic field sensor 43, which is attached to the lower jaw 38 or the upper jaw 37. Furthermore, the corresponding opposing jaw 37, 38 of the patient can be fixed in its position in space by means of a fixation, for example by means of a bite 35 or a chin holder 42.

A measured signal S of the measuring apparatus 10 is shown in FIG. In order to be able to feed the signal S into the ECG input 9 of the imaging system 6, it can for example be converted into a signal S 'which is similar to an ECG signal.

Since most imaging systems 6 use the R peak of the ECG as a reference point, it is usually easy to detect because it is a very narrow and intense signal. For this purpose, the signals S of the measuring apparatus 10 must be informed about the possible positions of the jaw be prepared according to the joint. A maximum or a minimum opening angle of the temporomandibular joint can be used, for example, as a virtual R-wave of the ECG, as indicated in FIG. 8. In order to convert signals S, such as those of an angle measurement into an ECG signal, additional technology is required. Since the voltages generated by the ECG electrodes are very low, a level adjustment must be made.

Some imaging systems 6 use so-called vector ECGs in which it is attempted to detect the vector of cardiac excitation. Again, for example, the signal S of the measuring apparatus 10 would have to be converted into a suitable, interpretable as a vector ECG signal, such as by generating two position signals Sl and S2 with 90 ° - phase to each other, as shown in Fig. 9.

In principle, this method can be imagined for magnetic resonance tomography, but also for other imaging methods, for example with X-rays and CT, as long as the radiation exposure permits this.

Claims

claims

1. Imaging system (6) for generating a 3D

Record of at least a portion of a jaw, comprising an image forming unit (11) for three-dimensional measurement of an object located in an examination volume, characterized in that a measuring apparatus (10) is present, at least during a recording or a recording series of the image forming unit (11) generates a signal (S), which corresponds to the relative position of the upper jaw (37) and the lower jaw (38) to each other in at least one direction of mobility and that an assignment of the images generated with image generating unit (11) to the at least one signal (S ) he follows.

2. Imaging system (6) according to claim 1, characterized in that a memory (7) for all during recording or the series of pictures of the image forming unit (11) generated signals (S) of the measuring apparatus (10) is provided.

3. An imaging system (6) according to claim 1 or 2, characterized in that the measuring apparatus (10) comprises a camera which receives two-dimensional images of at least a part of the head of a patient from which the at least one of the relative position of the upper jaw ( 37) and the lower jaw (38) mutually corresponding signal (S) can be generated.

4. Imaging system (6) according to one of claims 1 to 3, characterized in that the measuring apparatus (10) has at least one transmitter (29) by means of a holder (36) with the upper jaw (37) or the lower jaw (38) is connectable and that at least two receivers (30) are provided, which detect a signal transmitted by the at least one transmitter (29) spatially resolved at least in two dimensions.

5. Imaging system (6) according to claim 4, characterized in that a fixation for the opposing jaw

(37, 38) or at least one second transmitter (29) is provided, wherein the at least one second transmitter (29) by means of a holder (36) with the opposing jaw (37, 38) is connectable and the signal from that of the first transmitter (29 29) is distinguishable.

6. An imaging system (6) according to any one of claims 1 to 5, characterized in that the measuring apparatus (10) at least one receiver (30) and at least one of the receiver (30) visible marker (34) has, wherein the Marker (30) by means of a holder (36) with the upper jaw (37) or with the lower jaw (38) is connectable and the receiver (30) detects the orientation of the marker (34) spatially resolved.

7. Imaging system (6) according to claim 6, character- ized in that a fixation for the opposing jaw

(37, 38) or at least one second marker (34) is provided, wherein the second marker by means of a holder (36) with the opposing jaw (37, 38) connectable and distinguishable from the first marker (34).

8. An imaging system according to claim 1, wherein the measuring apparatus has a device for generating a homogeneous magnetic field and at least one gradient coil system for generating a gradient field and at least one of them acting as a receiving coil

Coil (40) is provided, which directly or by means of a ner holder (36) with the upper jaw (37) or with the lower jaw (38) is connectable.

9. Imaging system (6) according to claim 8, characterized in that a fixation for the opposing jaw (37, 38) or at least a second coil (40) is provided, wherein the second coil on the opposing jaw (37) is attachable.

10. Imaging system according to claim 1, characterized in that the measuring apparatus has at least one gradient coil system for generating a gradient field and at least one magnetic field sensor is provided directly or by means of a holder (36) with the upper jaw (37) or with the lower jaw (38) is connectable.

11. An imaging system (6) according to claim 10, characterized in that a fixation for the opposing jaw (37, 38) or at least a second magnetic field sensor (43) is provided, wherein the second magnetic field sensor on the opposing jaw (37) is attachable.

12. An imaging system (6) according to any one of claims 1 to 11, characterized in that the measuring apparatus (10) is formed as a biting apparatus having a Aufbissteil (1) for the upper jaw (37) and an up bissteil (2) for the lower jaw (38), the Aufbissteile (1, 2) are at least partially introduced into a patient's mouth and an alignment and movement of the upper jaw (37) and the lower jaw (38) follow and wherein the Aufbissteile (1, 2) via at least one joint (4; 12, 15, 16, 21, 22, 25) and / or at least one guide (13, 14, 17, 18, 19, 20, 23, 24) are movably connected to one another at least in one dimension and at least one sensor (5, 12 ', 13', 13 '', 16 ', 19', 20 ', 22', 24 ', 24'', 25 ') measures the position of the upstand parts (1, 2) relative to one another in at least one direction of mobility, so that an association of the images taken with the image generation unit (11) to the respective at least one angle (3) and / or the respective at least one shift between the Aufbissteilen (1, 2) can take place.

13. Imaging system (6) according to claim 12, characterized in that the upstand parts (1, 2) are designed as rails.

14. Imaging system (6) according to claim 12 or 13, characterized in that the upstand parts (1, 2) are respectively fixed to teeth of the upper jaw (37) or the lower jaw (38).

15. An imaging system (6) according to any one of claims 12 to 14, characterized in that the Aufbissappa- advice a restoring element (26).

16. An imaging system (6) according to any one of claims 12 to 15, characterized in that the at least one joint (4, 12, 15, 16, 21, 22, 25) and / or the at least one guide (13, 14, 17, 18, 19, 20, 23, 24), as well as the at least one sensor (5, 12 ', 13',

13 '', 16 ', 19', 20 ', 22', 24 ', 24' ', 25') of the bite apparatus are located outside the patient's mouth and are connected to the toe parts (1, 2).

17. Imaging system (6) according to one of claims 12 to 16, characterized in that the at least a joint (4, 12, 15, 16, 21, 22, 25) of the biting apparatus is movable about at least one axis of articulation orthogonal to a longitudinal axis (A) of the biting apparatus such that the upstand parts (1, 2) are at least at an angle (3 ) and that at least one angle sensor (5, 12 ', 16', 22 ', 25') for signal detection of the at least one angle (3) is provided.

18. An imaging system (6) according to any one of claims 12 to 17, characterized in that the Aufbissteile

(1, 2) along a guide (13, 14, 17, 18, 19, 20, 23, 24) in the direction of a longitudinal axis (A) of the bite apparatus are displaceable and that a position sensor (19 ', 20') for signal detection of Displacement is provided.

Imaging system (6) according to any one of Claims 12 to 18, characterized in that the upstand parts (1, 2) are transverse in one direction via a guide (13, 14, 17, 18, 19, 20, 23, 24) to a longitudinal axis (A) of the bite apparatus are displaceable and that a position sensor (13 ', 24') is provided for signal detection of the displacement.

20. An imaging system (6) according to any one of claims 12 to 19, characterized in that the Aufbissappa- advice has at least one locking means (27), which prevents at least one shift or tilting of the up parts (1, 2) against each other or at least one Angle (3) determines.

21. Imaging system (6) according to claim 20, character- ized in that a plurality of locking means in each case for at least one shifts and / or for at least an angle (3) are provided and can be used independently.

22. Imaging system (6) according to one of claims 1 to

21, characterized in that the imaging unit (11) is a magnetic resonance imaging apparatus, in particular a whole body tomograph or a head tomograph.

23. Imaging system (6) according to one of claims 1 to

22, characterized in that the imaging unit (11) is a computed tomography apparatus.

24. Imaging system (6) according to one of claims 1 to

23, characterized in that the image forming unit (11) is a sonography apparatus.

25. An imaging system according to any one of claims 1 to 24, characterized in that the at least one signal (S) of the measuring apparatus (10) in a computing unit (28) of the imaging system (6) is fed.

26. The imaging system according to claim 1, wherein the measuring apparatus generates at least two signals simultaneously, which are processed in a data processing unit into a single signal and the only one signal Signal (S) in a computing unit (28) of the imaging system (6) is fed.

27. An imaging system according to any one of claims 1 to 26, characterized in that a computing unit (28) having an input (9) for an electrocardiogram signal (S ') is provided and that a data processing unit (8) for the at least one signal (S) of the measuring apparatus (10) which processes the at least one signal (S) into a single signal (S) and the single signal (S) to the input (9) for an electrocardiogram signal (S ') of the computing unit (28) of the imaging system (6).

28. An imaging system according to any one of claims 1 to 27, characterized in that a computing unit (28) of the imaging system (6) at least one input

(9) for an electrocardiogram signal (S ') and that transmits the at least one signal (S) of the measuring apparatus (10) to the at least one input (9) for an electrocardiogram signal (S') of the arithmetic unit (28) becomes.

29. A method for generating a 3D data record of at least part of a jaw, characterized in that an imaging system (6) according to one of claims 1 to 26 is used and that during a movement of the temporomandibular joint data for a 3D data set at least a portion of the jaw with the image forming unit (11) of the imaging system (6) are generated and that at the same time to the data of the image forming unit (11) at least one signal (S) of the measuring apparatus (10) of the imaging system (6) recorded several times and the corresponding data is assigned.

30. The method according to claim 29, characterized in that the at least one signal (S) of the measuring apparatus

(10) is processed in a data processing unit (8) into a single signal (S), which is fed into a computing unit (28) of the imaging system (6).

31. The method according to claim 29, characterized in that the at least one signal (S) of the measuring apparatus (10) in a computing unit (28) of the imaging system (10) is fed.

32. Method according to one of claims 29 to 31, characterized in that the at least one signal (S) of the measuring apparatus (10) is processed in a data processing unit (8) to form a single signal (S) which is fed into the input (9). for an electrocardiogram signal (S ') of a computing unit (28) is fed.

33. The method according to claim 29 to 32, characterized in that a maximum or a minimum value of the at least one signal (S) of the measuring apparatus (10) is used as a virtual R-wave of the single signal.