FI124041B - Odontological imaging equipment - Google Patents

Description

FIELD OF THE INVENTION

The invention relates to a dental imaging apparatus according to the preamble of claim 1.

BACKGROUND OF THE INVENTION

10 The history of medical X-rays dates back roughly as far as the invention of X-rays. For more advanced imaging techniques, for example, in the field of dentistry, pan-frame X-ray imaging has begun to be developed over half a century ago. The development of digital imaging, particularly in the 1990s 15, has also brought digital X-ray equipment to the dental sector. The latest development in the dental field has seen the proliferation of tapered beam computed tomography equipment designed for 3D imaging of the dentition and other cranial region. Of the new opportunities they offer, 20 include applications related to implant placement and other treatment planning.

With the advent of cameras and computing power such as computers, it has become possible to produce virtual three-dimensional surface models of various surfaces. In the field of dentistry, facial surface models have been thought to be useful, for example, in dental orthodontics, where orthodontics can also have an effect on face shape. Such surface patterns o are sometimes combined with information on the texture of the surface, i.e.

CVJ

Of the 30 textures / structures, techniques are also known in the art for producing a virtual x g three-dimensional texture model without a separately produced model of the three-dimensional shape of the surface cd.

C/O

° 35 o o £ The use of facial texture models in dental 00 has been limited by e.g. the need for separate equipment purchases for that particular imaging purpose. Purchasing a stand-alone device is not only a cost but also a space issue, with each device always requiring some space in which it can be installed, stored and / or used. On the other hand, each individual imaging always takes a certain amount of time. In addition, in data processing, its own 5 challenges lie in arrangements that require the combination of image information acquired at different points in time, image information acquired by different imaging devices, and / or image information acquired from anatomy positioned in different ways to form the model.

10

BRIEF DESCRIPTION OF THE INVENTION

The object of the invention is a multifunctional dental imaging device which makes it possible to produce at least x-ray image information of the skull of the patient's skull for virtual 3D modeling of the patient's skull, and information on the patient's facial colors, scars, not only produces X-rays, but also three-dimensional images of the texture of the face. Preferably, the apparatus is configured to enable the production of 3D images of skull and / or bones of the skull, as well as information on both the shape and surface texture of the soft tissue of the face at the same patient placement and imaging. More specifically, the essential features of the invention are defined in the appended claims.

The invention provides a novel solution for versatile modeling of anatomy of a patient's skull. Thanks to the invention, e.g. utilizes the 5 existing imaging equipment fleets and avoids the need for special arrangements of the prior art, which lowers the threshold for dental practitioners to take advantage of the virtual $ 300 provided by virtual 3D models.

X

cc

CL

cc In the following, the invention and preferred embodiments thereof will be described in more detail with reference also to the accompanying drawings, o δ C \ 13

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 illustrates one imaging apparatus according to the invention, the basic structure of which comprises a support structure and a shaft portion supporting the imaging means.

Figure 2 illustrates one image information receiving module suitable for use in the apparatus of Figure 1.

Figure 3 illustrates the direction of laser beams from the module of Figure 2 toward a patient positioned in the imaging station.

Figures 4a and 4b show signal paths from an X-ray detector and at least one color camera via a frame grabber to a computer according to a preferred embodiment of the invention.

Figures 5a-5c show examples of various virtual three-dimensional face models.

Figure 6 illustrates the principle of controlling certain functions of the apparatus according to a preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows one imaging apparatus according to the invention. The apparatus comprises a vertical support structure (11) extending horizontally from the arm (12) supporting the patient support means and a shaft portion (13) supporting the structure imaging the apparatus imaging means, the arm portion (14). Imaging tools

CVJ

The 30 wide arm portion (14) may be arranged to be rotatable. A distance is provided on the shaft portion (14) supporting the imaging means

O

an x-ray source (15) and an x-ray image information receiver (21) disposed in the apparatus relative to the patient co-support means (17) such that the apparatus provides an imaging station (18) located on the x-ray source (15) and x-ray source (15). between the imaging information receiving means (21) such that the beam produced by the X-ray radiation source (15) can be directed to travel through said imaging station (18) towards the X-ray imaging information receiving means (21). The apparatus includes control means, of which Fig. 1 shows a control panel (16) arranged in the support structure (11) and associated mode selection means (19). In the apparatus of Figure 1, the X-ray image information receiving means (21) is arranged as part of an image information receiving module (20), which is provided via cable to a computer (30). The computer is provided with means for processing image information and a display (31) for displaying computer generated images.

10

Figure 2 shows one image information receiving module (20) suitable for use in the apparatus of Figure 1. In the module, two color cameras (22) directed toward the imaging station (18) are arranged horizontally on opposite sides of the x-ray detector (21). The module (20) is further provided with an imaging station (18) for illuminating preferably white light sources (23) and two lasers (24). These lasers are disposed substantially in the center of the module (20), substantially adjacent to its top and bottom edges. The lasers (20) are arranged to emit and direct 20 towards the imaging station (18) a narrow vertical planar beam that creates a laser pattern on the patient's face. Figure 3 shows how laser beams produced by the two lasers (24) shown in Figure 2 can be directed toward the imaging station (18) to cover the patient's face vertically without shadow areas.

25

The light sources (23) arranged in the apparatus may also be arranged to produce light or color light other than white. The color cameras (22), in turn, may also be provided in the apparatus with more than two or only one, and the cameras or camera (22) may be

CVJ

30 arranges to function not only as a photographic camera but also as a continuous ^ video camera. The patient's face pattern may also be produced by a light source other than a laser, and the color of this pattern may also be arranged to be interchangeable, and even when produced with a laser cc, it may be of a color other than conventional red, co g 35 mm. preferably δ δ 00 When the structure (14) supporting the imaging means of the apparatus of Figure 1 is pivotable, one or more color cameras (22) provided in the image information receiving module (20) can take pictures of faces of a patient positioned in the imaging station (18). . In this case, the laser pattern can also be made to sweep the patient's face. For example, using the mu-5 arrangement of Figure 2 with the camera (22) and laser (24) spaced apart, a laser line can scan the face of a patient positioned at the imaging station (18) while taking facial images at an angle (less than 90 degrees) to the laser beam. in the direction of. The resulting image information can produce a three-dimensional surface model of the shape of the patient's face. In a preferred embodiment of the invention, the hardware control system is provided with a control function for temporarily shutting down the laser at any desired time during scanning, during which time color photographs of the patient's face can be taken without laser image and the resulting image-15 format produces my patient's texture. On the other hand, in principle, it is also possible to operate in such a way that the laser is not turned off at all, but that the laser line is removed from the texture template to be generated by software processing the image information produced by imaging.

20

Figure 4a illustrates one of the signal paths used in the preferred embodiment of the invention from the image information receiving module (20) to the computer (30). The signal path of the image information detected by the color camera or cameras (22) and the X-ray detector (21) to the computer (30) can be arranged so that the image information received from them is transmitted to the computer (30) through the same single frame grabber. Preferably, the apparatus also provides a signal path between at least the motion control means of the X-ray imaging means and / or the X-ray source control means 30 and the computer via the same Ethernet cable as the signal path from the camera to the computer. This may be accomplished, for example 00, by means of an ethernet HUB component or ethernet switch component arranged in the hardware. Figure 4b shows another preferred embodiment for providing signal paths to the hardware, whereby only one ethernet cable between the imaging means and the computer is required,

o J

C \ 1 6

The means (32) provided in the computer (30) for processing image information obtained from a patient's face imaging station (18) comprise an algorithm for processing image information obtained from at least an X-ray detector (21) and image color information obtained from a color camera. My texture can either be generated from more than one-directional photographic information of the patient's face, or it can be produced using, for example, information from a patient's facial soft tissue surface obtained from X-ray imaging. In a preferred embodiment of the invention, the imaging means includes means for forming a face surface model of laser line waveformation on a patient's face, which information can be utilized to produce a three-dimensional texture pattern of the patient's face. Preferably, the imaging means include means for producing models that simultaneously display in 3D both the texture of the face and at least parts of the teeth and / or skeleton of the patient's cranial region.

20

Fig. 5a shows one example of a three-dimensional face model implemented with the apparatus of the invention, in which information on bone and teeth of a patient's cranial region is integrated into the face texture model. Fig. 5b in turn shows an exemplary facial surface model produced by the above-described apparatus according to the invention, and Fig. 5c shows a different projection of the model of Fig. 5b produced only from laser line patterns on the patient's face. A comparison of Figures 5b and 5c illustrates how the invention

CVJ

The facial texture pattern V produced by the i 30 hardware differs from the pure facial surface model.

o

CVJ

Fig. 6 is a diagram illustrating the principle according to which the known functions of the apparatus according to the above-described embodiment of the invention can be controlled. The figure assumes the patient's face? imaging to be performed - simultaneously with X-ray or self-imaging - by rotating the shaft portion (14) supporting the imaging means so that the image information receiving module (20) moves from one face of the patient to another at least 180 degrees, such as 200; degrees. During this movement, the patient's face is illuminated by continuously pulsing the light sources (23) of the image information receiving module (20), while the la-5 servo is otherwise continuously on, but is occasionally switched off during scanning to remove the patient's face positioned in the imaging station (18). even without laser photography. The hardware functions are synchronized to include two types of cycles, in which the laser light is switched off during the first cycles and images of the face are taken during illumination pulse cycles when the patient's face is illuminated, and during the second cycles the laser light is held (14) rotates to move along the patient's face and take images of the face during periods of such light pulses where the patient's face is not illuminated. When using two color cameras (22) according to an embodiment of the invention described above, in the mode of operation shown in FIG. 6, the above control is implemented such that the first and second cameras (22) always take pictures during successive light pulses. The image information integrated by the cameras (22) can always be read out during their light pulse cycles, whereby the image information is not integrated.

The diagram in Figure 6 thus illustrates one of the principles applicable to the invention. However, in order to prevent the patient in the imaging station from sensing the flicker of light due to the pulse of the face illumination, the illumination pulse frequency must be set to at least 50-60 Hz. Such a pulsation o would result precisely when operating as shown in Figure 6

CVJ

30 large amounts of image information unnecessary for the practice of the invention. Thus, the principle described above can be applied-

O

For example, during the periods described above, the first and second cameras do not take pictures during each light pulse co but only, for example, on the order of every tenth coo 35 pulse, which also allows more time to read the image information from the camera. Thus, in a preferred embodiment of the invention, the means for illuminating a patient's face are directed to illuminate the patient's face in short pulses, preferably at least at a frequency of 50-60 Hz, to control the laser or lasers to produce a laser there are periods, such as less than 10 periods, in which the laser pattern is not produced, and the color camera or cameras 5 are directed to take pictures in the first pulse stages, where the face is laser-patterned and illuminate the patient's face; directed laser light and whereby means for illuminating the patient's face illuminate the face.

10

One practical way to implement the imaging sequencing according to the practice described above involves performing the first and last episodes of the imaging means during periods in which the face is depicted without a laser line, such 15 cycles being sequentially performed for a total of five periods. Thus, in accordance with such an embodiment of the invention, a total of ten color photographs of the patient's face would be taken from different directions without laser light, and the angular velocity of the imaging means from one side of the patient's face to another could be arranged such that approximately 300 images of the face laser line were taken. However, it will be apparent to one skilled in the art that, for example, laser photo images need not be taken at even intervals, and that the number and positions at which laser line images are taken may vary, for example, according to the desired horizontal resolution of the texture. Also, facial photographs without a laser line do not need to be taken at even intervals, and their number and position can also be varied as needed to achieve suitable seam-5 positions and sufficient coverage to create a three-dimensional texture pattern

(M

Facial close-ups of 30 different directions, the apparatus of the invention and its mode selection switch (19)

X

The? Can be arranged to allow x-rays and a patient's face to be photographed, either separately or in a preferred embodiment of the invention, to be performed in connection with the same imaging event, even simultaneously. Photographing faces from different directions simultaneously during X-ray imaging eliminates the need for separate imaging. avoiding the need to calibrate another imaging device and position the patient on that other device for separate face imaging. This saves effort and saves time when face imaging can be performed concurrently with X-ray imaging. Also, if it is desired to integrate the image-5 formation obtained by different imaging modes, for example, to be represented in the same three-dimensional model, then combining is easier when the mapped anatomy has been in the same position in the coordinate system of the same imaging device. The apparatus enables the use of a la-servo to facilitate the appearance of facial contours as a tar-10 Kemp by moving the position of the laser line on the face, mapping the profiles generated by the laser line on the face, and calculating the face shape of these profiles.

The invention has been described above primarily with reference to the accompanying drawings, but not all of the above-described details of embodiments of the invention are necessary or practicable for the practice of the invention. The number of color cameras used in the equipment can be more than two, and if the equipment allows the camera to be positioned relative to the imaging position, one camera can already take pictures of the patient's face from different directions. In a preferred embodiment of the invention, a white light emitting arrangement is provided in the apparatus to illuminate a patient's face, which is advantageous for imaging facial tones, but the invention may also be utilized without one or more white light sources integrated with the apparatus. Further, sufficient information to produce a three-dimensional texture pattern of the face can be obtained by simply photographing the face from different directions, but preferred embodiments of the invention also utilize e.g.

CVJ

30 imaging information about facial soft tissue surface shapes or facial laser scan information about facial surface shapes.

cc

CL

According to the above embodiment, the image receiving receiver model suitable for use in the apparatus may comprise an X-ray image receiver (21) arranged substantially in the center of the module and two lasers (24) and substantially opposite ends of the module (20). the first and second color cameras (22) being arranged on the one hand, and the first and second lighting structures (23) on the other hand. Viewing the module (20) in the vertical direction, it may comprise an arrangement in which said lasers (24) are arranged substantially along the edges of the image information receiving module (20) and said lighting structures (23) to direct light toward the imaging station (18). above and below. However, the functionality of the invention for modeling at least a portion of the face is conceivably achievable by other types of arrangement, such as arrangement 10 using two light lines and only one camera.

The color camera included in the apparatus of the invention may be used for purposes other than those described above. The camera or cameras may also be arranged to function as a video camera, for example, to monitor and / or record the patient's facial expressions and potential movements prior to and / or during X-ray imaging, with appropriate arrangements also in 3D. The color camera or cameras in the above-described embodiments are located on a shaft portion supporting the imaging means substantially in the vicinity of the X-ray detector, but the color camera or cameras may also be arranged in the proximity of, for example, the X-ray source. In general, it is preferable to place the color camera or cameras, as well as any laser or lasers included in the apparatus, in an apparatus structure already arranged as a motion image with respect to the imaging station for X-ray purposes of the apparatus.

The computer included in the hardware need not be physically separate from the imaging means, but may also be integrated into the imaging device itself.

(M

The apparatus X-ray imaging means preferably enables computer tomography imaging, particularly the cone-beam computed tomography imaging known in the dental art, in which apparatus the cc 35 the vertical axis, which motion can also be directly utilized to produce photographic information to create a three-dimensional textural model of the face. This feature of the imaging equipment, in particular, makes it quite simple to perform laser scanning of the face, since the X-ray imaging device already has the means for performing the movements suitable for use in laser scanning. In many cases, La-5 laser scanning can significantly facilitate the detection of three-dimensional surface contours of a patient's face as compared to using information obtained solely from face color photography. Here, for example, a preferred embodiment of the invention refers to an arrangement in which said X-ray image information receiving means (21) comprises a detector having an image receiving area dimensions of at least an inch, said imaging means supporting structure (14) being arranged to be rotatable, (18), with the X-ray source (15) and the X-ray image receiving means (21) moving on opposite sides of the imaging station (18), wherein the hardware control system comprises a control routine which controls the imaging means 14 on the one hand. rotating motion, X-ray source 20 (15) and X-ray image receiving means (21) to produce image information, said means for processing (30) the information detected by the receiver (21), reconstructing a three-dimensional X-ray image and, on the other hand, directing said color camera (22) to take color images of the face of the patient positioned at the imaging position 25 (18). arranged to form a three-dimensional model on the display screen (31) for the imaging station (18)

C/O

5 positioned patients with at least a portion of the skull and / or teeth in the model and at least a portion of the facial texture of the patient;

CVJ

X

cc

CL

CD

C/O

O

O

O

δ

CVJ

Claims (22)

A dental imaging apparatus, comprising: 5. a support structure (11,13) for supporting an imaging device supporting structure (14), at least one imaging station (18) for positioning a patient for imaging, wherein the imaging means comprises at least an X-ray source (15). means for receiving X-ray imaging information (21) arranged in the apparatus relative to said imaging station (18) such that the X-ray source (15) and X-ray imaging information receiving means (21) are positioned on opposite sides of the imaging station (18) ), the beam to be produced is orientable through said imaging station (18) towards said means for receiving X-ray image information (21), a control system for controlling the functions of the imaging apparatus, and means for operatively communicating the information detected by the X-ray imaging information receiver (21), wherein the structures, components and control means associated with the X-ray imaging of the apparatus are arranged to enable dental medical computed tomography and / or or other illumination arrangement adapted to direct the photographic imaging station (18) to the face-space of the patient positioned on the imaging station (18), - means for photographing (22) and for producing an image of g from the patient's face in at least two directions, the means comprising at least one color camera (22) having a position relative to the magnitude 35 of said imaging station arranged to be changed and / or at least a color camera arranged to depict the face of the patient positioned in the patient base station (18) from different directions, means integrated with or operatively connected to the device for forming a three-dimensional surface model of the patient face with photographic information of said face; for combining with the at least one color camera (22) image information formed by said at least one color camera (22) or a three-dimensional texture pattern thereof, at least a portion of the patient's x-ray imaging information integrated into the three-dimensional texture model Bone and / or dentition in the Allon area. The imaging apparatus of claim 1, characterized in that the apparatus control system comprises means for performing x-ray imaging and patient face imaging simultaneously and / or as a combined imaging during a single imaging event, and / or the apparatus control system comprises selection means for performing x-ray imaging and patient face imaging. at least one of the foregoing means, or at least one of said two descriptions, to be implemented as a separate representation. Imaging apparatus according to claim 1 or 2, characterized in that the apparatus comprises at least one illuminating gap q structure (23) for illuminating the face of a patient positioned on the imaging station (18). 1 2 o Imaging apparatus according to Claim 3, characterized in that said at least one illuminator structure (23) and / or a true color camera (22) is arranged in the apparatus such that the patient's face can be illuminated and imaged in different directions with the patient 2 positioned. said x-ray imaging station (18). Imaging apparatus according to claim 3 or 4, characterized in that said means for illuminating a patient's face (23) are arranged to comprise a light structure directing light towards the face 5 of a patient arranged in an imaging station (18) substantially above and below said color camera (22). . Imaging apparatus according to any one of claims 1 to 5, characterized in that said means for illuminating the face of the patient (23) and at least one color camera (22) are arranged in the proximity of said X-ray image information receiver (21). Imaging apparatus according to one of Claims 1 to 6, characterized in that the apparatus comprises at least two color cameras (22) and are arranged to be horizontally spaced apart. Imaging apparatus according to one of claims 3 to 6, characterized in that the apparatus control system comprises means for controlling said means to illuminate (23) the patient's face to produce white light, to produce white light pulsed and / or to produce different colored lights. Imaging apparatus according to one of Claims 1 to 7, characterized in that the apparatus comprises at least two color cameras (22) arranged in connection therewith an illuminating structure (23) which directs light towards the face of a patient positioned in the imaging station (18) and substantially at least two color cameras. 22) from above and below, the at least two color cameras (22) and the light fixtures (23) disposed adjacent thereto are arranged horizontally at a distance O ^ to each other on opposite sides of said X-ray image receiver E1 (21). CD CO g 35 Imaging apparatus according to one of Claims 3 to 9, characterized in that said means for illuminating a patient's face (23) and at least one color camera (22) are arranged in connection with said imaging means supporting structure (14). Imaging apparatus according to one of Claims 1 to 10, characterized in that said imaging device supporting structure (14) is arranged to be pivotable with respect to a virtual vertical axis passing through the patient base station (18). The imaging apparatus according to any one of claims 1 to 11, characterized in that said imaging device-supporting structure (14) is arranged to be rotated at least 180 degrees with respect to the imaging station (18) and an apparatus control system to control said at least one color camera (22) a photograph of the face of the patient positioned in the imaging station (18) in said angle region. Imaging apparatus according to one of Claims 1 to 12, characterized in that the information detected by said X-ray image receiver (21) and at least one color camera (22) is arranged to be fed to the same single frame grabber, and / or the same single Ethernet cable. via an imaging device to physically separate means for processing image information (30). Imaging apparatus according to any one of claims 1 to 13, characterized in that said means for forming a surface model of a patient's face include at least one laser or other light source (24) illuminating the face of a patient positioned on a narrow vertical photographic imaging station (18). the imaging device support structure (14), and that said imaging device support structure (14) and said imaging station (18) are arranged to be movable with respect to one another such that said image is orientated substantially at different locations within the patient. facial area, x X CL cd Imaging apparatus according to Claim 14, characterized in that the apparatus comprises two lasers (24) arranged on substantially the same vertical virtual axis, or a corresponding photo-generating light source arranged relative to the imaging station (18) such that the upper one illuminates the patient's face at least slightly upwards and the lower one at least slightly downwards. Imaging apparatus according to Claim 14 or 15, characterized in that said imaging means supporting structure (14) is provided with an image information receiving module (20) housing at least a portion of said means: an X-ray image information receiver (21), at least one color camera. (22), means for illuminating the face (23) and means for producing laser or 10 other patterns (24). Imaging apparatus according to any one of claims 14 to 16, characterized in that said imaging device supporting structure (14) is arranged to be rotated with respect to the imaging station (18), said photographic movement according to the motion of said imaging device supporting structure (14) and to take tens or hundreds of photographs from different directions of said photograph at said at least one color sea (22) within said range of motion of the imaging support structure (14). 20 Imaging apparatus according to Claim 16 or 17, characterized in that, viewed horizontally, an image information receiving module (20), substantially in the center thereof, is provided with an X-ray image information receiver (21) and two lasers or the like (24) and 20) first and second color cameras (22) and first and second luminaire structures (23) are provided at opposite ends, and that said lasers or the like CvJ '30 (24), viewed in the vertical direction, are arranged in said image information receiving module (22). 20) substantially along its edges, and said luminaire structures (23) to direct light toward the imaging station (18) from above and below said color cameras (22). CD CO § 35 Imaging apparatus according to one of Claims 14 to 18, characterized in that the apparatus control system comprises a control routine which controls the structure (14) supporting the imaging means to rotate with respect to the imaging station (18), during which the means illuminate the patient's face. 23) guiding the patient's face positioned in imaging station (18) in short 5 pulses, preferably at least 50 Hz, laser, lasers or the like (24) directing to produce a photographic pattern on the patient's face otherwise continuously but with moments of rotation of the imaging device supporting structure (14). , wherein the photographic pattern is not produced, and 10 - the color camera or cameras (22) are guided to take pictures in the first stages of face-facing and means for illuminating the face of the patient (23) and in the second stages of e is not a photographic pattern and wherein the means for illuminating the patient's face (23) illuminates the face. An imaging apparatus according to claim 19, characterized in that said imaging device-supporting structure (14) is arranged to rotate with respect to the imaging station (18) by at least 180 degrees, and according to said control routine, there are short periods such as less than 10 , wherein the patient's face is not oriented on the pattern and wherein the color camera or cameras (22) are guided to take pictures in steps whereby means for illuminating the patient's face produce a light pulse. Imaging apparatus according to any one of claims 1 to 20, characterized in that said X-ray image receiving means (21) comprises a detector having an image receiving area of at least an inch, said structure supporting the imaging means. (14) is arranged to be pivotable with respect to the virtual pivot axis passing through the vertical stationary imaging station (18) such that the x-ray source (15) and the receiving means (21) of the x-ray image information c0 are moving opposite to the imaging station (18). on the one hand, that the apparatus control system comprises a control routine which, on the one hand, controls said imaging means to carry a rotation of the body (14), an X-ray source (51) and X-ray image receiving means (21) to produce image information. means for processing (30) the information detected by the X-ray image information receiver (21), on the other hand, directing at least 5 said color cameras (22) 30) is configured to form a three-dimensional model of 10 patients positioned on the imaging station (18) displayed on the display screen (31), wherein at least a portion of the skull and / or teeth of the patient's skull is visible; Apparatus according to any one of claims 1 to 21, characterized in that the apparatus comprises means for producing and directing a green laser or other light beam towards the face of the patient positioned towards the imaging station to form a substantially vertical narrow light line on the face. co δ {M o C \ 1 X DC CL CD CO O O O δ {M