KR102383546B1 - Apparatus and method for oral image registration - Google Patents

Abstract

The present invention provides a method of registering an oral scan image and a CT image, comprising the steps of segmenting a first marker and a first tooth area in an oral scan image, respectively, and integrating the first marker and the first tooth area to obtain a first registration reference point generating a , dividing the second marker and the second tooth region in the CT image, and integrating the second marker and the second tooth region to generate a second registration reference point; first and second registration Provided is an oral image registration method comprising the step of registering an oral scan image and a CT image based on a reference point.

Description

Oral image registration device and method {APPARATUS AND METHOD FOR ORAL IMAGE REGISTRATION}

The present invention relates to an oral image registration device and method.

In computer vision, when a scene or object is photographed from a different time or point of view, images according to different coordinate systems are obtained. Image registration refers to processing for transforming such different images and displaying them in one coordinate system.

Through such image registration, it is possible to check the correspondence between images obtained through different measurement methods.

In a dental surgical guide software, an image registration process between a computed tomography (CT) image and an oral scan image is generally performed before entering the dental implant procedure planning stage.

The image registered through this image registration process becomes the basis for implant planning work that determines the safe and optimal implant placement position by identifying the bone tissue and neural tube position, so the accuracy of image registration is very important in the subsequent procedure. have

In the image registration method provided by the conventional medical software, an operator manually inputs a point that is a reference point for image registration, and image registration is performed based on this.

According to such a conventional image registration method, since the operator selects the reference point by roughly judging by the eye, the result is very inaccurate, so that the operator's manual operation process is inevitably followed after image registration. That is, the operator modifies the registration result by changing the position of the point or reselecting the point. As described above, according to the prior art, the operator spends a lot of time in image registration due to the continuous iterative process of registration and correction, and there is a problem in that satisfactory results cannot be obtained as much as the time spent.

As another conventional method, there is a method of acquiring an image including a marker for use as an intraoral registration standard, and matching an image obtained from a heterogeneous imaging device based on the marker in the image.

1 is a view showing a marker attached to the inside of the oral cavity for image registration.

Referring to FIG. 1 , a plurality of markers 1 are attached to a predetermined position in the oral cavity of the recipient using an adhesive (eg, resin). After that, when a certain time elapses, an adhesive layer 2 is formed between the marker 1 and the gums. At this time, since the amount and shape of the adhesive are different for each attachment position of the marker 1 , the shape of the adhesive layer 2 becomes non-uniform.

On the other hand, in detecting the marker 1 in the oral image for image registration, since the marker 1 and the adhesive layer 2 are integrally formed, the marker 1 and the adhesive layer 2 can be detected together. However, the non-uniform adhesive layer 2 becomes an obstacle to registration during image registration, and causes a problem of lowering the registration accuracy during image registration.

The present invention is to provide an oral image registration apparatus and method for segmenting a marker and a tooth region in an oral image, but removing elements that interfere with registration from the marker, and automatically performing image registration with high accuracy using the segmented marker The purpose.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those of ordinary skill in the art to which the present invention belongs from the description below. There will be.

In order to solve the above problems, the present invention provides a method of matching an oral scan image and a CT image, comprising the steps of segmenting a first marker and a first tooth region in an oral scan image, respectively, the first marker and the first tooth Generating a first registration reference point by integrating the regions, dividing the second marker and the second tooth region in the CT image, and generating a second registration reference point by integrating the second marker and the second tooth region and registering an oral scan image and a CT image based on first and second registration reference points.

Here, the step of segmenting the first marker in the oral scan image includes aligning the oral scan image in a horizontal plane direction, estimating a marker candidate region in the aligned oral scan image, and detecting an undivided marker in the marker candidate region. An oral image registration method comprising the steps of: estimating a first marker from the undivided marker by dividing the undivided marker, and estimating an area up to a predetermined depth from the upper surface of the undivided marker to a lower direction as the first marker provides

In addition, the step of dividing the first marker from the oral scan image includes generating a first learning model by learning a plurality of first learning images to which the first markers are attached, and inputting the oral scan image to the first learning model. and detecting an undivided marker in the oral scan image based on the first training image.

In addition, the step of segmenting the first tooth region in the oral scan image includes calculating curvatures of a plurality of meshes included in the oral scan image, and the first tooth region in the oral scan image based on the curvatures of the plurality of meshes. and calculating a boundary of the gum area, and segmenting the first tooth area in the oral scan image based on the boundary between the first tooth area and the gum area.

In addition, the step of segmenting the second marker in the CT image is a step of detecting the second marker in the CT image using volume information of the second marker.

In addition, segmenting the second marker in the CT image includes generating a mask in a shape corresponding to the second marker using volume information of the second marker, and selecting the second marker in the CT image using the mask. It includes the step of exploring.

In addition, the step of segmenting the second tooth region in the CT image may include: generating a second learning model by learning the second learning image based on hounsfield unit (HU) values of a plurality of voxels included in the CT image; inputting the CT image to a second learning model; and segmenting a second tooth region in the CT image based on the second learning image.

In addition, the present invention provides an apparatus for matching an oral scan image and a CT image, the first marker dividing unit dividing a first marker in the oral scan image, and a first tooth region dividing the first tooth region in the oral scan image A division unit, a first registration reference point generating unit generating a first registration reference point by integrating the first marker and the first tooth region, a second marker division unit dividing the second marker in the CT image, and a second marker in the CT image. A second tooth region dividing unit dividing the two tooth regions, a second registration reference point generating unit generating a second registration reference point by integrating the second marker and the second tooth region, and the first and second registration reference points based on the first and second registration reference points Provided is an oral image matching device including an image matching unit for registering an oral scan image and a CT image.

According to the present invention, a marker and a tooth area are segmented in an oral image, but elements that interfere with registration are removed from the marker, and image registration is automatically performed with high accuracy using the segmented marker and tooth area to improve user convenience and , it has the effect of reducing the time required for implant planning and improving the accuracy of implant planning.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned may be clearly understood by those of ordinary skill in the art to which the present invention belongs from the following description. will be.

1 is a view showing a marker attached to the inside of the oral cavity for image registration.
2 is a schematic block diagram of an oral image registration apparatus according to an embodiment of the present invention.
FIG. 3 is a detailed block diagram of the control unit of FIG. 2 .
4 is a flowchart of an oral image registration method according to an embodiment of the present invention.
5 is a diagram illustrating an oral scan image generated by photographing an oral cavity to which a marker is attached.
6 is an enlarged view of an undivided marker.
7 is a diagram illustrating a marker divided from the undivided marker of FIG. 6 .
8 is a diagram for explaining a method of calculating the curvature of a plurality of meshes included in an oral scan image.
9 is a diagram illustrating a tooth region divided in an oral scan image based on the curvatures of a plurality of meshes calculated in FIG. 8 .
10 is a diagram illustrating a first matching reference point in an oral scan image.
11 is a view illustrating a CT image generated by photographing an oral cavity to which a marker is attached.
12 is a diagram illustrating a marker detected in the CT image of FIG. 11 .
13 is a diagram illustrating a segmented tooth region in a CT image.
14 is a diagram illustrating a second matching reference point on a CT image.
15 is a diagram illustrating registration of an oral scan image and a CT image by an oral image registration method according to an embodiment of the present invention.

The above object and means of the present invention and its effects will become more apparent through the following detailed description in relation to the accompanying drawings, and accordingly, those of ordinary skill in the art to which the present invention pertains can easily understand the technical idea of the present invention. will be able to carry out In addition, in describing the present invention, if it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

In this specification, terms such as “or” and “at least one” may indicate one of the words listed together, or a combination of two or more. For example, “or B” and “at least one of B” may include only one of A or B, or both A and B.

In this specification, terms such as 'first' and 'second' may be used to describe various components, but the components should not be limited by the above terms. In addition, the above terms should not be construed as limiting the order of each component, and may be used for the purpose of distinguishing one component from another. For example, a 'first component' may be referred to as a 'second component', and similarly, a 'second component' may also be referred to as a 'first component'.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a schematic block diagram of an oral image registration apparatus according to an embodiment of the present invention, and FIG. 3 is a detailed block diagram of the controller of FIG. 2 .

The oral image registration apparatus 100 according to an embodiment of the present invention is an electronic device executable by a computer program, and is an apparatus for matching an oral scan image and a CT image of a recipient by using a marker and a tooth region as a registration reference point. Here, the tooth region may be one individual tooth or a form in which a plurality of adjacent individual teeth are combined, and the number of markers may be at least one, but is not limited thereto. Also, a marker may be attached to the missing tooth area.

The oral scan image may provide information on the shape of the crown portion of the tooth exposed to the outside as a 3D image and the shape of the gum around the tooth. At this time, the oral scan image is obtained by directly scanning the inside of the recipient’s oral cavity through an oral scanner, etc. The scan image of the impression model can be inverted and used as an oral scan image.

The CT image, as a three-dimensional image, may provide information on not only the crown, but also the shape of the root and alveolar bone, and the bone density of the crown, root, and alveolar bone. In this case, the CT image may be obtained by performing a CT scan of the inside of the recipient's oral cavity.

The registered image, in which the oral scan image and the CT image are matched, becomes the basic image for implant planning work that determines the safe and optimal implant placement position by identifying the bone tissue and neural tube position of the recipient.

Referring to FIG. 2 , the oral image matching apparatus 100 according to an embodiment of the present invention may include a communication unit 110 , an input unit 120 , a display unit 130 , a storage unit 140 , and a control unit 150 . can

The communication unit 110 is a component that communicates with an external device such as an image acquisition device (not shown) and a server (not shown), and may receive image data. For example, the communication unit 110 is 5 ^th generation communication (5G), long term evolution-advanced (LTE-A), long term evolution (LTE), Bluetooth, bluetooth low energe (BLE), near field communication (NFC). It is possible to perform wireless communication such as cable communication and the like, and can perform wired communication such as cable communication. In this case, the image data may include oral scan image data and CT image data.

The input unit 120 generates input data in response to a user's input, and may include at least one input means. For example, the input unit 120 includes a keyboard, a keypad, a dome switch, a touch panel, a touch key, a mouse, and a menu button ( menu button) and the like.

The display unit 130 displays display data according to the operation of the oral image matching apparatus 100 . The display data may include image data. For example, the display unit 130 may include a liquid crystal display (LCD), a light emitting diode (LED) display, an organic light emitting diode (OLED) display, and a micro electromechanical system (MEMS). mechanical systems) displays and electronic paper displays. Also, the display unit 130 may be combined with the input unit 120 to be implemented as a touch screen.

The storage unit 140 stores various information and programs necessary for the operation of the oral image matching apparatus 100 . For example, the storage 140 may store image data received from an image acquisition device, etc., and an algorithm related to image alignment, marker and tooth region detection, and image registration method according to an embodiment of the present invention, which will be described later. . Also, the storage unit 140 may store a learning model obtained by learning a plurality of learning images by a deep learning method in order to detect a marker and a tooth region.

The control unit 150 detects a marker and a tooth region from oral image data received from an image acquisition device or server or pre-stored in the storage unit 140, and matches the oral image data using the detected marker and the tooth region as a reference point. perform the action To this end, the control unit 150 may receive the oral image data from the image acquisition device or the server and store it in the storage unit 140 . Also, the controller 150 may control the operations of the communication unit 110 , the input unit 120 , the display unit 130 , and the storage unit 140 .

Referring to FIG. 3 , the controller 150 includes a first marker dividing unit 151 , a first tooth region dividing unit 152 , a first matching reference point generating unit 153 , a second marker dividing unit 154 , It may include a second tooth region dividing unit 155 , a second matching reference point generating unit 156 , and an image matching unit 157 .

First, the image acquisition device acquires an oral scan image and a CT image, respectively, by photographing the inside of the oral cavity to which the marker is attached. In this case, the acquired oral scan image and CT image may be directly transmitted to the image alignment unit 151 or may be stored in the storage unit 140 and then transmitted to the image alignment unit 151 .

The first marker divider 151 divides the first marker in the oral scan image. Specifically, the first marker divider 151 aligns the oral scan image in a horizontal plane direction, estimates a marker candidate region from the aligned oral scan image, and detects an undivided marker in the marker candidate region. Then, the first marker is estimated from the undivided marker by dividing the undivided marker, and a region up to a certain depth from the top surface of the undivided marker to the bottom is estimated as the first marker.

The first tooth region dividing unit 152 divides the first tooth region in the oral scan image. Specifically, the first tooth region dividing unit 152 calculates curvatures of a plurality of meshes included in the oral scan image, and a boundary between the first tooth region and the gum region in the oral scan image based on the curvatures of the plurality of meshes. to calculate Then, the first tooth area is divided in the oral scan image based on the boundary between the first tooth area and the gum area.

The first registration reference point generating unit 153 generates a first registration reference point by integrating the first marker and the first tooth region.

The second marker divider 154 divides the second marker in the CT image. Specifically, the second marker dividing unit 154 generates a mask in a shape corresponding to the second marker by using the volume information of the second marker, searches for the second marker in the CT image using the mask, and searches for the second marker. split the

The second tooth region dividing unit 155 divides the second tooth region in the CT image. Specifically, the second tooth region dividing unit 155 generates a second learning model by learning the second learning image based on hounsfield unit (HU) values of a plurality of voxels included in the CT image, and performs the second learning process. By inputting the oral scan image to the model, a second tooth region is divided in the CT image based on the second learning image.

The second registration reference point generating unit 156 generates a second registration reference point by integrating the second marker and the second tooth region. In addition, the image matching unit 157 matches the oral scan image and the CT image based on the first and second matching reference points.

As described above, according to the oral image registration apparatus 100 of the present invention, the marker and the tooth region are divided in the oral image, but elements that interfere with registration are removed from the marker, and the image is registered with high accuracy using the divided marker and the tooth region. is performed automatically to enhance the user's convenience, thereby reducing the time required for implant planning and improving the accuracy of implant planning.

Hereinafter, a method of registering an oral image of an oral image according to an embodiment of the present invention controlled by the controller 150 will be described.

In the oral image registration method according to an embodiment of the present invention, an oral image is taken while a marker is attached to the gums of the recipient, and the oral image is matched using the marker and the tooth area as a reference point.

4 is a flowchart of an oral image registration method according to an embodiment of the present invention.

First, a marker is attached to a plurality of positions (eg, gums) in the recipient's oral cavity using an adhesive such as a resin, particularly in the area of a missing tooth. At this time, when a predetermined time elapses, an adhesive layer is formed between the marker and the gum. Thereafter, a heterogeneous image acquisition device captures the inside of the oral cavity to which the marker is attached to acquire an oral scan image and a CT image, respectively.

Referring to FIG. 4 , the oral image registration method according to an embodiment of the present invention is a method of registering an oral scan image and a CT image using a marker and a tooth region, and includes a first marker and a first tooth region in the oral scan image. dividing (S10), generating a first registration reference point by integrating the first marker and the first tooth region (S20), and dividing the second marker and the second tooth region in the CT image (S30) ), generating a second registration reference point by integrating the second marker and the second tooth region (S40), and registering the oral scan image and the CT image based on the first and second registration reference points (S50) may include

5 is a view showing an oral scan image generated by photographing an oral cavity to which a marker is attached, FIG. 6 is an enlarged view of the undivided marker, and FIG. 7 is a marker divided from the undivided marker of FIG. It is a drawing.

Hereinafter, a method of segmenting the first marker 11a in the oral scan image 10 will be described with reference to FIGS. 5 to 7 . Hereinafter, the first marker 11a and the adhesive layer 12 will be collectively referred to as an undivided marker.

5 to 7 , the oral scan image 10 is aligned in the horizontal direction so that the marker 11a faces upward in the oral scan image 10 . Then, a marker candidate region is estimated from the aligned oral scan image 10 , and an undivided marker is detected from the marker candidate region.

The undivided marker may be detected using a learning model. That is, by using a deep learning method (eg, You Only Look Once (YOLO) algorithm), a first learning model is generated by learning a plurality of learning images to which the first marker 11a is attached, and the generation An undivided marker may be detected from the oral scan image 10 by inputting the oral scan image 10 of the recipient to the first learning model. Here, information on the number, size, and coordinates of undivided markers may be obtained.

Since the undivided marker includes the non-uniform adhesive layer 12 as well as the first marker 11a, that is, since the first marker 11 and the adhesive layer 12 are integrally formed, the shape is non-uniform. Accordingly, in order to improve the matching accuracy, it is necessary to divide the first marker 11a from the undivided marker.

Referring to FIG. 6 , an area from the top surface of the undivided marker to a predetermined depth d1 in the downward direction is estimated as the first marker 11a. In addition, an area exceeding the predetermined depth d1 (eg, 5 mm) in the undivided marker is estimated as the adhesive layer 12 interposed between the first marker 11a and the gum. That is, an area from the lower surface of the undivided marker to a predetermined height d2 in the upper direction is estimated as the adhesive layer 12 . Accordingly, the marker 11 can be divided from the undivided marker 11b (S10).

On the other hand, unlike the drawing, by aligning the oral scan image 10 in the horizontal plane direction so that the first marker 11a in the oral scan image 10 faces downward, the undivided marker is detected and the first marker from the undivided marker (11a) may be divided. At this time, the area from the lower surface of the undivided marker to a predetermined height d1 in the upward direction is estimated as the first marker 11a, and the predetermined height d1 (eg, 5 mm) is exceeded in the undivided marker. The area is estimated as the adhesive layer 12 interposed between the first marker 11a and the gum.

8 is a view for explaining a method of calculating the curvatures of a plurality of meshes included in the oral scan image, and FIG. 9 is a tooth region divided in the oral scan image based on the curvatures of the plurality of meshes calculated in FIG. 8 It is the drawing shown.

Hereinafter, a method of segmenting the first tooth region in the oral scan image will be described with reference to FIGS. 8 and 9 .

Curvatures of a plurality of meshes included in the oral scan image 10 are calculated, and a boundary between the first tooth region 13a and the gum region is calculated in the oral scan image 10 based on the curvatures of the plurality of meshes.

Specifically, a plane that includes a normal vector and intersects the mesh surface is drawn in a vertex shared by adjacent meshes, and then the plane is rotated based on the normal and continuously intersects the mesh surface. In this case, a number of curves centered on the vertex can be obtained on the mesh surface, and the curvature can be calculated using the angle between these curves and the tangent plane of the vertex. In addition, the largest value among these curvatures may be defined as the maximum curvature, and the smallest value may be defined as the minimum curvature. Meanwhile, a plane including two curves having the largest maximum curvature and the smallest minimum curvature at the vertex among the calculated curvatures may be defined as a plane of principal curvatures.

Here, the Gaussian curvature is defined as the product of the maximum curvature and the minimum curvature, and the average curvature is defined as the average of the maximum curvature and the minimum curvature.

Meshes in which at least one of the Gaussian curvature and the average curvature calculated in this way is equal to or greater than the reference curvature are selected, and a vertex shared by the selected meshes is determined as a boundary point.

Then, the boundary points are sequentially expanded (dilation) and reduced (erosion) using a morphology calculation algorithm to connect adjacent boundary points. Here, the morphology calculation algorithm is an algorithm for expanding and reducing a region, and is generally used for connecting or disconnecting adjacent points.

In this way, when the boundary points are expanded and then reduced through the reduction process, the boundary between the teeth and the gum region can be further improved because only the connection between adjacent boundary points is performed while maintaining the thickness of the existing boundary point component.

Accordingly, the first tooth area 13a may be divided in the oral scan image 10 based on the boundary between the first tooth area 13a and the gum area ( S10 ).

10 is a diagram illustrating a first matching reference point in an oral scan image.

As shown in FIG. 10 , the first marker 11a and the first tooth region 13a that are respectively divided in the oral scan image 10 are integrated to become a standard for matching the oral scan image 10 and the CT image. A first matching reference point is generated (S20).

11 is a diagram illustrating a CT image generated by photographing an oral cavity to which a marker is attached, and FIG. 12 is a diagram illustrating a marker detected in the CT image of FIG. 11 .

10 and 11 , the second marker 11b may have a three-dimensional shape (eg, a cuboid) having a predetermined volume. Here, the volume of the rectangular parallelepiped may be defined as the product of width, length, and height (eg, 4 mm×5 mm×5 mm). In addition, at least one second marker 11b may be attached to a predetermined position in the oral cavity (eg, gum), but is not limited thereto.

Meanwhile, referring to FIG. 11 , the second marker 11b may be made of a radiopaque material (eg, alumina), and the adhesive layer 12 may be made of a radioactive material. Accordingly, in the CT image 20 , the second marker 11b including the crown, tooth root, and alveolar bone is displayed, but the adhesive layer 12 is not displayed. Accordingly, in the CT image 20 , it is not necessary to divide the second marker 11b and the adhesive layer 12 like the oral scan image 10 . However, it is difficult to accurately detect the second marker 11b because it is not easy to distinguish between the crown, tooth root, and alveolar bone and the second marker 11b.

In order to accurately detect the second marker 11b in the CT image 20 as described above, the second marker 11b is detected and divided in the CT image 20 using the volume information of the second marker 11b ( S30). Specifically, a mask is created in a shape corresponding to the second marker 11b by using the volume information of the second marker 11b. Then, the second marker 11b is searched for in the CT image 20 using the mask, and the second marker 11b having a shape corresponding to the mask is detected and divided. Here, information on the number, size, and coordinates of the second markers 11b may be obtained.

13 is a diagram illustrating a segmented tooth region in a CT image.

Referring to FIG. 13 , the second tooth region 13b in the CT image 20 may be detected using a learning model. That is, by using a deep learning method, a second learning model is generated by learning a second learning image based on hounsfield unit (HU) values of a plurality of voxels included in the CT image 20 , 2 The CT image 20 is input to the learning model, and the second tooth region 11b is detected from the CT image 20 based on the second learning image.

14 is a diagram illustrating a second matching reference point on a CT image.

As shown in FIG. 14 , a criterion for matching the oral scan image 10 and the CT image 20 by integrating the second marker 11b and the second tooth region 13b respectively divided in the CT image 10 . A second matching reference point is generated (S40).

15 is a diagram illustrating registration of an oral scan image and a CT image by an oral image registration method according to an embodiment of the present invention.

Referring to FIG. 15 , the first mark 11a and the first tooth area divided in the oral scan image 10 and the second marker 11b and the second tooth area divided in the CT image 20 are matched as reference points, respectively. Thus, the oral scan image 10 and the CT image 20 are automatically matched (S50).

As described above, according to the oral image registration method of the present invention, the marker and the tooth region are divided in the oral image, but elements that interfere with registration are removed from the marker, and the image registration is automatically performed with high accuracy using the divided marker and the tooth region. There is an effect of improving the convenience of the user by performing the procedure, and thereby reducing the time required for the implant planning and improving the accuracy of the implant planning.

In the detailed description of the present invention, although specific embodiments have been described, various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention is not limited to the described embodiments, and should be defined by the following claims and their equivalents.

100: oral image registration device
150: control unit
151, 154: first and second marker division parts
152, 155: first and second tooth region divisions
153 and 156: first and second matching reference point generators
157: image matching unit

Claims (8)

A method of registering an oral scan image and a CT image, the method comprising:
dividing a first marker in the oral scan image by a first marker dividing unit, and dividing a first tooth region in the oral scan image by a first tooth region dividing unit;
generating, by a first registration reference point generating unit, a first registration reference point by integrating the first marker and the first tooth region;
dividing a second marker in the CT image by a second marker dividing unit, and dividing a second tooth region in the CT image by a second tooth region dividing unit;
generating, by a second registration reference point generating unit, a second registration reference point by integrating the second marker and the second tooth region; and
Comprising an image matching unit matching the oral scan image and the CT image based on the first and second registration reference points,
The step of dividing the second marker in the CT image by the second marker dividing unit
generating a mask in a shape corresponding to the second marker by using the volume information of the second marker; and
and searching for the second marker in the CT image using the mask.
Oral image registration method.
The method of claim 1,
The step of dividing the first marker in the oral scan image by the first marker dividing unit
aligning the oral scan image in a horizontal direction;
estimating a marker candidate region from the aligned oral scan image, and detecting an undivided marker in the marker candidate region; and
estimating the first marker from the undivided marker by dividing the undivided marker, and estimating, as the first marker, an area up to a certain depth from the upper surface of the undivided marker to a lower direction
Oral image registration method comprising a.
The method of claim 1,
The step of dividing the first marker in the oral scan image by the first marker dividing unit comprises:
generating a first learning model by learning a plurality of first learning images to which the first markers are attached;
inputting the oral scan image to the first learning model; and
detecting an undivided marker in the oral scan image based on the first learning image
Oral image registration method comprising a.
The method of claim 1,
The step of dividing the first tooth region in the oral scan image by the first tooth region dividing unit comprises:
calculating curvatures of a plurality of meshes included in the oral scan image; and
calculating a boundary between the first tooth region and the gum region in the oral scan image based on the curvatures of the plurality of meshes; and
dividing the first tooth area in the oral scan image based on the boundary between the first tooth area and the gum area
Oral image registration method comprising a.
The method of claim 1,
The step of dividing the second marker in the CT image by a second marker dividing unit comprises:
detecting the second marker in the CT image by using the volume information of the second marker
Oral image registration method.
delete The method of claim 1,
The step of dividing the second tooth region in the CT image by the second tooth region divider comprises:
generating a second learning model by learning a second learning image based on hounsfield unit (HU) values of a plurality of voxels included in the CT image;
inputting the CT image to the second learning model; and
Segmenting the second tooth region in the CT image based on the second learning image
Oral image registration method comprising
An apparatus for registering an oral scan image and a CT image, comprising:
a first marker dividing unit dividing a first marker in the oral scan image;
a first tooth region dividing unit for dividing a first tooth region in the oral scan image;
a first registration reference point generating unit generating a first registration reference point by integrating the first marker and the first tooth region;
a second marker dividing unit dividing a second marker in the CT image;
a second tooth region dividing unit for dividing a second tooth region in the CT image;
a second registration reference point generating unit generating a second registration reference point by integrating the second marker and the second tooth region; and
an image matching unit for matching the oral scan image and the CT image based on the first and second registration reference points;
The second marker dividing unit
generating a mask in a shape corresponding to the second marker by using the volume information of the second marker, and searching for the second marker in the CT image using the mask
Oral image registration device.

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