JP2021069464A - Abutment tooth formation support device - Google Patents

Abstract

To provide an abutment tooth formation support device for supporting formation of a high quality abutment tooth.SOLUTION: An abutment tooth formation support device 2 comprises: first input means which acquires image information of an abutment tooth 12a; reference direction e setting means which sets the reference direction e of the abutment tooth 12a from the image information; shape information calculation means which obtains the shape information of the surface of the abutment tooth 12a from the reference direction e and the image information; and display means which displays the shape information of the surface together with the image information. Preferably, the reference direction e setting means sets the direction in which an area of a portion to be the undercut becomes the minimum as the reference direction e when viewing the abutment tooth 12a while changing the direction of viewing the abutment tooth 12a.SELECTED DRAWING: Figure 3

Description

The present invention relates to a device that supports abutment tooth formation.

In recent years, digital devices have come to be used for dental care and dental care education. For example, IOS (Intra-Oral-Scanner) and CAD / CAM devices are used in the production of a prosthesis to be placed on an abutment tooth. IOS scans the abutment tooth in the oral cavity, the teeth around it, and the gingiva to acquire three-dimensional image information. The obtained image information is sent to a CAD / CAM device, and data for producing a prosthesis is created.

There is also a great demand for devices that support the formation of abutment teeth. This is because if a good quality abutment tooth can be formed, a high quality filling material that is easy to chew and hard to come off can be produced. For example, Japanese Patent Application Laid-Open No. 2014-20968 discloses an abutment tooth formation support device for dental education. This support device includes a camera and an evaluator. A model of the oral cavity is prepared for use of this device. The trainee cuts the teeth of this model to form the abutment teeth. The imager takes an image of this abutment tooth and sends it to the evaluator. The evaluator compares this to an image of an ideal abutment tooth formed by a skilled physician. As a result, the abutment tooth formed by the trainee is evaluated, and the result is fed back to the trainee.

Japanese Unexamined Patent Publication No. 2014-20968

In the actual medical field, there is no ideal abutment tooth. A support device that does not require this ideal abutment tooth is required. In addition, in order to support the formation of high-quality abutment teeth, it is important to feed back the information on the surface of the abutment teeth to doctors and trainees in an easy-to-understand manner. An abutment tooth formation support device for this purpose is desired.

An object of the present invention is to provide an abutment tooth formation support device for supporting the formation of high quality abutment teeth.

The abutment tooth formation support device according to the present invention is a first input means for acquiring three-dimensional image information of an abutment tooth, a reference direction setting means for setting a reference direction of the abutment tooth from the image information, and the above. A shape information calculation means for obtaining shape information on the surface of the abutment tooth from a reference direction and the image information, and a display means for displaying the shape information on the surface together with the image information are provided.

Preferably, the reference direction setting means sets the direction in which the area of the undercut portion is minimized when the abutment tooth is viewed while changing the viewing direction of the abutment tooth as the reference direction.

The second input means for acquiring the tooth root information of the abutment tooth may be further provided, and the reference direction setting means may set the reference direction from the position of the tooth root and the image information of the abutment tooth. In this case, preferably, the tooth root information acquired by the second input means is an image of the tooth root taken by an imager using an X-ray.

When the virtual tubular body extending parallel to the reference direction from the finish line of the abutment tooth is defined as the tubular body V, preferably, the shape information is the inner peripheral surface of the tubular body V and the said. The distance from the surface of the abutment tooth.

The shape information may be an angle between the surface of the abutment tooth and the reference direction.

Preferably, the display means colors the surface of the tooth according to the shape information to display image information of the abutment tooth of the tooth.

The abutment tooth formation support program according to the present invention is a process of setting the reference direction of the abutment tooth from the three-dimensional image information of the abutment tooth to the arithmetic unit, and the reference direction and the image information are described as described above. A process for obtaining the shape information of the surface of the abutment tooth and a control process for displaying the shape information of the surface together with the image information are executed.

This abutment tooth formation support device is a means for setting a reference direction (reference direction) for evaluating the state of the surface of the formed abutment tooth, and shape information of the surface of the abutment tooth from this reference direction. It is provided with a calculation means for obtaining the above and a display means for displaying the shape information together with the image information of the abutment tooth. With this support device, the quality of the abutment tooth can be easily confirmed without preparing the ideal abutment tooth. With this device, high quality abutment teeth can be efficiently formed.

FIG. 1 is a configuration diagram of an abutment tooth formation support device according to an embodiment of the present invention. FIG. 2 is an example of tooth image information acquired by the image input device of FIG. FIG. 3 is a flow chart showing processing by the arithmetic unit of FIG. FIG. 4 is a schematic view illustrating undercutting of teeth. FIG. 5 is a diagram illustrating a part of the reference direction setting process of FIG. FIG. 6 is a schematic view showing a tubular body used in the reference direction setting process of FIG. FIG. 7 is a diagram illustrating a part of the shape information calculation process of FIG. FIG. 8 is a diagram in which the shape information obtained by the shape information calculation process of FIG. 1 is displayed together with the image of the tooth. FIG. 9 is a configuration diagram of an abutment tooth formation support device according to another embodiment of the present invention. FIG. 10 is a diagram illustrating a part of the shape information calculation process according to still another embodiment of the present invention. FIG. 11 is a diagram in which the shape information calculated by the shape information calculation process of FIG. 10 is displayed together with the image of the tooth.

Hereinafter, the present invention will be described in detail based on preferred embodiments with reference to the drawings as appropriate.

[First Embodiment]

FIG. 1 shows an abutment tooth formation support device 2 according to an embodiment of the present invention. Abutment teeth are formed by cutting the teeth. The support device 2 displays information on the surface of the abutment tooth formed by the user (doctor or trainee). This information is used, for example, in the field of medical education to evaluate the formed abutment tooth. In the actual medical field, if it is judged necessary from this information, cutting will be further advanced. The device 2 includes an image input device 4, a user setting input device 6, a calculation unit 8, and a display device 10.

The image input device 4 photographs the inside of the oral cavity and acquires three-dimensional image information. In the medical field, the image input device 4 is inserted into the oral cavity of the patient, and the abutment tooth 12a formed by cutting the tooth 12 and its peripheral portion are photographed. In the field of medical education, for example, an oral model is photographed. FIG. 2 shows a part of the captured image information. In FIG. 2, the tooth 12 located at the center is the abutment tooth 12a. The image input device 4 is typically an IOS (Intra-Oral-Scanner) that scans the oral cavity and acquires three-dimensional image information. The image input device 4 constitutes a first input means. The image input device 4 constitutes the first input device.

In this embodiment, the image information acquired by the image input device 4 is represented by a set of a large number of triangles. This situation is schematically shown in the square surrounded by the alternate long and short dash line in FIG. As shown in this figure, the surface of the tooth 12 is divided into a large number of triangles 14, and the coordinates of the vertices of each triangle 14 are the image information of the teeth 12. The method of expressing image information is not limited to this method. For example, the image information may be represented by a set of other polygons such as a quadrangle. The image information may be represented in other ways.

The user setting input device 6 is used when the user of the present device 2 operates the present device 2. The user setting input device 6 typically includes a keyboard and a mouse. The user setting input device 6 may be composed of a touch panel.

The calculation unit 8 creates information that supports the formation of abutment teeth from the image information in the oral cavity. As shown in FIG. 1, the arithmetic unit 8 includes an arithmetic unit 16, a memory 18, and a peripheral circuit 20. The arithmetic unit 16 refers to hardware that executes processing according to a program instruction. A typical arithmetic unit 16 is a CPU. The memory 18 stores a program for controlling the arithmetic unit 16, image information, and the like. The peripheral circuit 20 is, for example, an interface circuit for an image input device 4, a user setting input device 6, and a display device 10.

FIG. 3 shows the processing performed by the arithmetic unit 8. As shown in the figure, the calculation unit 8 executes the reference direction setting process S1 and the shape information calculation process S2. In this embodiment, the calculation unit 8 constitutes a reference direction setting means and a shape information calculation means. The calculation unit 8 is a reference direction setter and a shape information calculator. Further, the arithmetic unit 8 executes the display control process S3 for controlling the display 10. These processes are carried out by the program stored in the memory 18 controlling the arithmetic unit 16 and the like. These processes are carried out programmatically.

The configuration of the arithmetic unit 8 is not limited to the configuration shown in FIG. For example, the calculation unit 8 may have a dedicated circuit for the reference direction setting process S1 and the shape information calculation process S2. In this case, these dedicated circuits are a reference direction setter and a shape information calculator, respectively.

The display 10 displays the surface shape information calculated by the calculation unit 8 together with the image information acquired by the image input unit 4. A typical display 10 is an LCD monitor. The display 10 may be a touch panel. In this case, the display 10 also serves as the user setting input device 6. In this embodiment, the display 10 and the calculation unit 8 that performs the display control process S3 constitute the display means. These form the display unit of the present device 2.

In the following, it is carried out by the arithmetic unit 8.
(A) Reference direction setting process S1,
(B) Shape information calculation process S2
And (C) Display control process S3
The contents of are explained.

The reference direction setting process S1 of the above (A) sets the reference direction of the abutment tooth 12a. The "reference direction" is a reference direction for evaluating the state of the surface of the abutment tooth 12a. Here, the reference direction is "the direction in which the area of the undercut portion is minimized when the abutment tooth 12a is viewed while changing the viewing direction of the abutment tooth 12a".

FIG. 4 is a schematic diagram for explaining the undercut portion. When the tooth 12 is viewed from a predetermined direction, the portion that cannot be seen behind the other portion of the tooth 12 is the undercut portion 22 in this direction. In FIG. 4, the arrow indicates the direction in which the tooth 12 is viewed, and the hatched portion indicates the undercut portion 22.

The reference direction setting process S1 of the above (A) is
(A1) Step of recognizing the range of the abutment tooth 12a,
(A2) A step of searching for a direction in which the area of the undercut portion is minimized while changing the viewing angle of the abutment tooth 12a in the first plane.
(A3) The step of searching for the direction in which the area of the undercut portion is minimized while changing the viewing angle of the abutment tooth 12a in the second plane, and (A4) the step of determining the reference direction are included.

In the step (A1) above, the range of the abutment tooth 12a is recognized from the image information. In other words, in this step, a group of triangles 14 forming the abutment tooth 12a is selected from a large number of triangles 14 which are image information.

In this step, the user first specifies the abutment tooth 12a with the user setting input device 6. In the example of FIG. 2, the arrows represent the positions specified using the mouse. For the triangle 14 located at the designated location (in the example of FIG. 2, the shaded triangle 14a in the two-dot chain line square), the direction of the perpendicular of this triangle 14a (hereinafter, this is simply a "triangle"). The direction of) is examined. Starting from this triangle 14a, the directions of the triangles 14 located around it are examined in order. When the angle formed by these directions of two adjacent triangles 14 is equal to or greater than a predetermined value, the boundary of these triangles 14 is a candidate for the boundary of the abutment tooth 12a. If the directions of these surrounding triangles 14 are examined and the candidates for this boundary extend continuously, this is determined to be the boundary of the abutment tooth 12a. In FIG. 2, the symbol L represents the boundary (finish line) of the abutment tooth 12a with the gum portion. The triangle 14 located in the region surrounded by the finish line L is the triangle 14 forming the abutment tooth 12a.

In the step (A2) above, the angle at which the abutment tooth 12a is viewed is changed in one plane (in the first plane), and the area of the undercut portion is calculated in each direction. As a result, the direction in which the area of the undercut portion in the first plane is minimized is selected. In this embodiment, this process is
(A2-1) A step of roughly changing the angle to select the direction in which the area of the undercut portion is minimized, and (A2-2) A step of finely changing the angle to select the direction in which the area of the undercut portion is minimized. Includes steps to select.

FIG. 5 shows the state of the above step (A2-1). In FIG. 5, the thick arrow is the direction in which the abutment tooth 12a is viewed. In this figure, the angle at which the abutment tooth 12a is viewed is coarsely changed (at large intervals) in the horizontal plane. In this figure, the direction in which the abutment tooth 12a is viewed is changed at 10 ° intervals in this plane. For each direction, the area of the undercut portion is calculated and the direction with the smallest value is selected. If there are multiple minimum directions, all of them are selected. In the example of FIG. 5, for example, the direction A is selected.

In the step (A2-2), the angle at which the abutment tooth 12a is viewed is finely changed in the vicinity of the direction A in the first plane as compared with the step (A2-1). For example, the viewing direction is changed at 1 ° intervals with the direction A as the center. For each direction, the area of the undercut portion is calculated and the direction with the smallest value is selected. In the example of FIG. 5, for example, the direction a indicated by a thin arrow is selected. If there are multiple minimum directions, the center direction of these is selected.

In the step (A3) above, the angle at which the abutment tooth 12a is viewed is changed in a plane (in the second plane) different from that in the above (A2), and the direction in which the area of the undercut portion is the smallest is selected. Will be done. Usually, the plane orthogonal to the first plane is referred to as the second plane. In the example of FIG. 5, the angle at which the abutment tooth 12a is viewed is changed in the vertical plane. In the second plane, the same processing as (A2-1) and (A2-2) above is performed. As a result, the direction b in which the area of the undercut portion is minimized in the second plane is selected.

In the step (A4), the central direction between the direction a obtained in the step (A2) and the direction b obtained in the step (A3) is set as the reference direction e. For example, the sum vector of the unit vector pointing in the direction a and the unit vector facing the direction b is calculated, and the direction of the resulting vector is set as the reference direction e. This completes the process of setting the reference direction.

In the above embodiment, in the two planes in the first plane and the second plane, the angle at which the abutment tooth 12a is viewed is changed, and the direction in which the area of the undercut portion is the smallest is selected. The number of planes that change the viewing angle of the abutment tooth 12a may be 3 or more. In this case, in each plane, the direction in which the area of the undercut portion is the smallest is selected, and the central direction of these directions is set as the reference direction e.

In the shape information calculation process S2 of the above (B), the shape information of the surface of the abutment tooth 12a with respect to the reference direction e is calculated. In this process, the distance between the inner peripheral surface of the virtual "cylindrical body V" and the surface of the abutment tooth 12a is used as shape information. FIG. 6 is a schematic view showing the tubular body V. In this figure, the tubular body V is represented by a chain double-dashed line. The tubular body V is formed by extending the finish line L of the abutment tooth 12a in parallel with the reference direction e.

In the step (B) above, the distance between the tubular body V and the surface of the abutment tooth 12a is obtained in the following steps (see FIG. 7).
(B1) For the triangle 14 constituting the surface, the intersection P between the line extending in the direction of the triangle 14 and the tubular body V is obtained from one vertex v1 of the triangle 14. Further, a straight line ep that passes through the intersection P and extends in the reference direction e is obtained. This is shown in FIG.
(B2) The distance between the straight line ep and the apex v1 is calculated, and this is taken as the distance between the tubular body V and the apex v1.
(B3) The distance to the tubular body V is calculated for all the vertices of all the triangles 14 constituting the surface of the abutment tooth 12a.
(B4) As shown in FIG. 2, the positions of the vertices of the triangle 14 are shared by the plurality of triangles 14. That is, the vertices of the plurality of triangles 14 overlap. The average value of the above distances calculated in each triangle is taken as the distance between the abutment tooth 12a and the tubular body V at this position. The obtained distance is used as shape information at this position on the surface of the abutment tooth 12a.

In the display control process S3 of the above (C), the information of the distance between the tubular body V and the surface of the abutment tooth 12a calculated in the above (B) is the corresponding position of the surface of the abutment tooth 12a as color information. Attached to. At this time, between the adjacent vertices, colors having gradually changed hues are added, from the color of one vertex to the color of the other vertex. These are sent to the display 10. As a result, on the display 10, the surface of the abutment tooth 12a is displayed in red, for example, at a position where the distance is far, and is displayed in a gradually changing hue such as yellow, blue, and purple as the distance becomes shorter. .. FIG. 8 shows an example of the display result of the abutment tooth 12a with this color, although it is difficult to understand because the color cannot be expressed.

The method of coloring the surface is not limited to the above. A gradation from white to black according to the above distance may be applied to the surface of the abutment tooth 12a. For example, the surface of the abutment tooth 12a is displayed in black at a position where the distance is long, and is displayed so as to gradually approach white as the distance becomes short. As described above, in the present invention, the case of adding a gradation from white to black on the surface is also included in "coloring the surface".

Hereinafter, the effects of the present invention will be described.

In the abutment tooth formation support device 2 according to the present invention, by designating a part of the abutment tooth 12a, this device recognizes the range of 2 and the abutment tooth 12a, and the reference direction e of the abutment tooth 12a. To set. In this device 2, the user does not need to set the reference direction e. This device 2 makes it possible to efficiently form a high-quality abutment tooth 12a.

When inserting the prosthetic device, the presence of undercuts in the formed abutment teeth can result in the prosthetic device not being fully fixed. It is necessary that the formed abutment tooth does not have an undercut. In the abutment tooth formation support device 2, the direction in which the area of the undercut portion is minimized is set as the reference direction e. The abutment tooth 12a is evaluated with reference to this reference direction e. As a result, the abutment tooth 12a can be efficiently evaluated from the viewpoint of forming the abutment tooth 12a without undercut. As a result, the user can efficiently form the high quality abutment tooth 12a.

In the abutment tooth formation support device 2, the distance between the tubular body V formed by extending the finish line L of the tooth 12a in parallel with the reference direction e and the surface of the abutment tooth 12a is the abutment. It is used as the shape information of the tooth 12a. By this method, the user can easily recognize the unevenness of the surface with respect to the reference direction e. As a result, the user can easily confirm the quality of the abutment tooth 12a. This effectively contributes to the formation of high quality abutment teeth 12a.

In the abutment tooth formation support device 2, color information corresponding to the above distance is attached to the surface of the abutment tooth 12a, and this is displayed on the display 10 together with the image of the abutment tooth 12a. The user can recognize at a glance the unevenness of the surface with respect to the reference direction e. The user can easily confirm the quality of the abutment tooth 12a. This device 2 makes it possible to efficiently form a high-quality abutment tooth 12a.

In this abutment tooth formation support device 2, it is not necessary for the user to prepare an ideal abutment tooth in order to confirm the quality of the abutment tooth 12a. There is no need to send the information of the formed abutment tooth 12a to the technician and wait for feedback. In this device 2, the quality of the abutment tooth 12a can be efficiently confirmed without preparing an ideal abutment tooth. This device 2 makes it possible to efficiently form high-quality abutment teeth 12a even in the medical field.

[Second Embodiment]

FIG. 9 shows an abutment tooth formation support device 30 according to another embodiment of the present invention. Similar to the device 2 of FIG. 1, the device 30 includes an image input device 32, a user setting input device 34, a calculation unit 36, and a display device 38. The device 30 further includes an X-ray camera 40. This device 30 is the same as the device 2 in FIG. 1 except for the X-ray radiographer 40 and the arithmetic unit 36 into which data from the radiographer 40 is input.

The X-ray imager 40 takes an X-ray image of a tooth to be cut and sends the image information to the calculation unit 36. The X-ray camera 40 is typically a CT scanning device. Although not shown, this image information includes information from the cutting portion (the portion exposed from the gums) to the root of the tooth to be cut. The X-ray camera 40 constitutes a second input means. The X-ray camera 40 constitutes a second input device.

The calculation unit 36 creates information that supports the formation of abutment teeth from the image information in the oral cavity. As shown in FIG. 9, the arithmetic unit 36 includes an arithmetic unit 42, a memory 44, and a peripheral circuit 46, similarly to the arithmetic unit 8 of FIG. In the calculation unit 36, the reference direction setting process S'1, the shape information calculation process S'2, and the display control process S'3 are executed in the same manner as in the calculation unit 8 of FIG.

The reference direction setting process S'1 sets the reference direction of the abutment tooth. Here, the reference direction is set from the position of the tooth root and the image information of the abutment tooth. This is done in the following steps.
(A'1) The range of the abutment tooth is recognized from the image information from the image input device 32. This is the same as the process of (A1) in FIG.
(A'2) The abutment tooth is associated with the tooth of the X-ray photographed image, and the root protrusion position of the tooth root is specified in the image information of the image input device 32.
(A'3) The reference direction of the abutment tooth is set from the information on the abutment tooth and the root protrusion position of the tooth root. Specifically, the direction of intersection between the surface connecting the incisal end of the crown and the root tip when the abutment tooth is viewed from the mesial side and the surface passing through the center of the incision when the abutment tooth is viewed from the labial side is It is the reference direction.

When the reference direction is set, the shape information calculation process S'2 is executed based on the reference direction, and the display control process S'3 is further executed. These are the same as the shape information calculation process S2 and the display control process S3 of the device 2 of FIG. 1, respectively. In the abutment tooth formation support device 30, as in the device 2 of FIG. 1, color information corresponding to the distance between the tubular body V and the surface of the abutment tooth is attached to the surface of the abutment tooth and displayed. Will be done.

In the abutment tooth formation support device 30 according to the present invention, the reference direction is set from the information of the abutment tooth and the tooth root. When the tooth is bitten, a large force is applied to the tooth toward the root tip of the tooth root. Ideally, the prosthetic device should be inserted in this direction. By setting the reference direction from the information of the abutment tooth and the tooth root, it is possible to easily form the abutment tooth capable of matching the direction in which this force is applied and the insertion direction of the prosthetic device. A prosthetic device can be stably attached to the abutment tooth. This device 30 makes it possible to form high quality abutment teeth.

[Third Embodiment]

Although not shown, the abutment tooth formation support device according to still another embodiment of the present invention has the same configuration as the device of FIG. This apparatus is the same as these processes in FIG. 3 except for the shape information calculation process and the display control process performed by the arithmetic unit.

In the shape information calculation process, the shape information of the surface of the abutment tooth 50 with respect to the reference direction is calculated. In this process, the angle between the reference direction and the surface of the abutment tooth 50 is calculated as shape information. This is calculated in the following steps (see FIG. 10).

(B'1) With respect to the triangle 52 forming the surface, the angle θe between the line extending in the direction of the triangle 52 from one vertex v1 of the triangle 52 and the line extending in the reference direction e is obtained. The angle θv (θv = 90-θe) obtained by subtracting this angle θe from 90 ° is defined as the angle between the surface and the reference direction e at this apex. This is shown in FIG.
(B'2) At the positions of all the vertices of all the triangles 52 constituting the surface of the abutment tooth 50, the angle between the surface and the reference direction e is obtained.
(B'3) The positions of the vertices of the triangle 52 are shared by the plurality of triangles 52. The vertices of the plurality of triangles 52 overlap. The average value of the above angles obtained for each triangle is taken as the angle at this position on the surface. The obtained angle is used as the shape information of this surface.

In the display control process, information on the angle between the reference direction e calculated in (B) above and the surface of the abutment tooth 50 is attached to the corresponding position on the surface as color information. In this embodiment, the display control process applies color information according to the angle to the surface of the abutment tooth. For example, the surface of the abutment tooth is displayed in red at a position where the angle is large, and is displayed in a gradually changing hue such as yellow, blue, and purple as the angle becomes smaller. FIG. 11 shows an example of the display result of the abutment tooth 50 with this color.

This abutment tooth formation support device attaches color information corresponding to an angle with respect to a reference direction to the surface of the abutment tooth 50, and displays this together with an image of the abutment tooth 50 on a display. The user can recognize at a glance the unevenness of the surface with respect to the reference direction. As a result, the user can easily confirm the quality of the abutment tooth 12a. This device makes it possible to efficiently form high quality abutment teeth.

[Other Embodiments]

In the step (B) above, the distance between the apex of each triangle and the tubular body V was obtained. As another embodiment, the center of gravity of the triangle, the tubular body V, and the distance may be calculated, and this may be used as the shape information. In this case, the shape information calculation process is performed in the following steps.
(B "1) For the triangle forming the surface, the intersection P of the line extending in the direction of this triangle and the tubular body V is obtained from the center of gravity of this triangle. Further, the intersection P is passed through the intersection P and in the reference direction. An extending straight line ep is obtained. The distance between this ep and the center of gravity is defined as the distance between the triangle and the tubular body V.
(B "2) For all the triangles constituting the surface of the abutment tooth, the distance from the tubular body V is obtained. The obtained distance is used as the shape information of the surface at the position of this triangle.

In the reference direction setting process, the user may set this by using the user setting input device. Further, the reference direction set in the above reference direction setting process may be changed by the user by using the user setting input device.

As described above, with this abutment tooth formation support device, high quality abutment teeth can be efficiently formed. From this, the superiority of the present invention is clear.

The abutment tooth formation support device described above can be applied to abutment tooth formation in dentistry and dental care education.

2, 30 ... Abutment tooth formation support device 4, 32 ... Image input device 6, 34 ... User setting input device 8, 36 ... Calculation unit 10, 38 ... Display 12, 50・ ・ ・ Teeth 14, 52 ・ ・ ・ Triangle 16, 42 ・ ・ ・ Computer 18, 44 ・ ・ ・ Memory 20, 46 ・ ・ ・ Peripheral circuit 22 ・ ・ ・ Undercut part 40 ・ ・ ・ X-ray camera

Claims (8)

First input means for acquiring 3D image information of abutment teeth,
A reference direction setting means for setting a reference direction of the abutment tooth from the image information,
A shape information calculation means for obtaining shape information on the surface of the abutment tooth from the reference direction and the image information.
An abutment tooth formation support device including a display means for displaying the shape information of the surface together with the image information. According to claim 1, the reference direction is the direction in which the area of the undercut portion is minimized when the reference direction setting means looks at the abutment tooth while changing the viewing direction of the abutment tooth. The abutment tooth formation support device described. Further provided with a second input means for acquiring information on the root of the abutment tooth,
The abutment tooth formation support device according to claim 1, wherein the reference direction setting means sets the reference direction from the position of the tooth root and the image information of the abutment tooth. The abutment tooth formation support device according to claim 3, wherein the tooth root information acquired by the second input means is an image of the tooth root taken by an imager using an X-ray. When the virtual tubular body extending parallel to the reference direction from the finish line of the abutment tooth is defined as the tubular body V, the shape information is the inner peripheral surface of the tubular body V and the abutment tooth. The abutment tooth formation support device according to any one of claims 1 to 4, which is the distance from the surface of the abutment tooth. The abutment tooth formation support device according to any one of claims 1 to 4, wherein the shape information is an angle between the surface of the abutment tooth and the reference direction. The abutment tooth formation support according to any one of claims 1 to 6, wherein the display means colors the surface of the abutment tooth according to the shape information and displays the image information of the abutment tooth. apparatus. For arithmetic units
Processing to set the reference direction of the abutment tooth from the three-dimensional image information of the abutment tooth,
A process of obtaining shape information on the surface of the abutment tooth from the reference direction and the image information.
A program for supporting the formation of abutment teeth, which executes a control process for displaying the shape information of the surface together with the image information.

Images