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EP-4364692-B1 - INTRAORAL IMAGE PROCESSING DEVICE AND INTRAORAL IMAGE PROCESSING METHOD

EP4364692B1EP 4364692 B1EP4364692 B1EP 4364692B1EP-4364692-B1

Inventors

  • LEE, SUNG HOON
  • LEE, DONG HOON

Dates

Publication Date
20260506
Application Date
20220613

Claims (15)

  1. An intraoral image processing method comprising: obtaining three-dimensional (3D) intraoral data (500) on an oral cavity comprising teeth and a gingiva; and generating an outer surface of a target tooth that is a subject of a prosthesis from among the teeth included in the 3D intraoral data (500), wherein the generating of the outer surface comprises automatically generating a portion corresponding to a void area between the target tooth and at least one adjacent tooth adjacent to the target tooth, and the portion corresponding to the void area is generated based on a virtual margin line (630) by using a first tooth point and a second tooth point, wherein the first tooth point is located at a position equal to or less than a preset threshold value from a first gingiva point on a boundary of a first gingiva (510), and the second tooth point is located at a position equal to or less than the preset threshold value from a second gingiva point on a boundary of a second gingiva (520).
  2. The intraoral image processing method of claim 1, wherein the generating of the outer surface comprises generating the portion corresponding to the void area, based on the 3D intraoral data.
  3. The intraoral image processing method of claim 2, wherein the generating of the outer surface comprises generating the portion corresponding to the void area, based on data adjacent to the void area in the 3D intraoral data.
  4. The intraoral image processing method of claim 1, wherein the generating of the outer surface comprises: identifying the virtual margin line between the target tooth and the gingiva, based on the 3D intraoral data; and generating the outer surface, based on the target tooth and the identified virtual margin line.
  5. The intraoral image processing method of claim 4, wherein the generating of the outer surface comprises generating a portion of the outer surface corresponding to the void area, based on a portion of the virtual margin line corresponding to the void area.
  6. The intraoral image processing method of claim 4, wherein the generating of the outer surface comprises: identifying a virtual target tooth by identifying a virtual bottom face corresponding to a bottom face of the target tooth based on the virtual margin line, and connecting the virtual bottom face to the target tooth; and generating the outer surface, based on the virtual target tooth and the virtual margin line.
  7. The intraoral image processing method of claim 4, wherein the identifying of the virtual margin line comprises: for each of points of the target tooth, selecting at least one of the points of the target tooth, by identifying a point whose distance to at least one of points included in a boundary of the gingiva is equal to or less than the preset threshold value, based on data corresponding to the boundary of the gingiva and the target tooth in the 3D intraoral data; and identifying the virtual margin line by connecting the selected at least one point.
  8. The intraoral image processing method of claim 6, wherein the identifying of the virtual target tooth comprises: identifying the virtual bottom face, by expanding a reference surface identified based on the virtual margin line in a direction opposite to an occlusal direction of the target tooth; and identifying the virtual target tooth, by merging the virtual bottom face with the target tooth.
  9. The intraoral image processing method of claim 8, wherein the generating of the outer surface comprises: aligning the virtual target tooth with the virtual margin line, and dividing the virtual target tooth into areas along the virtual margin line; and generating the outer surface, by identifying an area in the occlusal direction from among the areas of the virtual target tooth.
  10. The intraoral image processing method of claim 6, further comprising: identifying an expanded reference surface, by expanding a reference surface identified based on the virtual margin line; identifying a virtual adjacent gingiva for a gingiva adjacent to the target tooth, by merging the expanded reference surface with a surface obtained by expanding the expanded reference surface in a direction opposite to an occlusal direction; and generating the outer surface, based on the virtual adjacent gingiva and the virtual target tooth.
  11. The intraoral image processing method of claim 10, wherein the generating of the outer surface comprises generating the outer surface of the target tooth, by booleaning the virtual adjacent gingiva and the virtual target tooth.
  12. The intraoral image processing method of claim 8, wherein the identifying of the virtual target tooth comprises identifying the virtual target tooth by merging the virtual bottom face with the target tooth and smoothing a merged area.
  13. An intraoral image processing device (300) comprising: a memory (310) storing one or more instructions; and a processor (320) configured to execute the one or more instructions stored in the memory to obtain three-dimensional (3D) intraoral data on an oral cavity comprising teeth and a gingiva, and generate an outer surface of a target tooth that is a subject of a prosthesis from among the teeth included in the 3D intraoral data, wherein a portion corresponding to a void area between the target tooth and at least one adjacent tooth adjacent to the target tooth is automatically generated, and the portion corresponding to the void area is generated based on a virtual margin line (630) by using a first tooth point and a second tooth point, wherein the first tooth point is located at a position equal to or less than a preset threshold value from a first gingiva point on a boundary of a first gingiva (510), and the second tooth point is located at a position equal to or less than the preset threshold value from a second gingiva point on a boundary of a second gingiva (520).
  14. The intraoral image processing device of claim 13, wherein the processor (320) is further configured to execute the one or more instructions stored in the memory (310) to generate a portion corresponding to the void area, based on the 3D intraoral data, identify the virtual margin line between the target tooth and the gingiva, based on the 3D intraoral data, and generate the outer surface, based on the target tooth and the identified virtual margin line.
  15. A computer-readable recording medium having recorded thereon a program which, when executed, causes a computer to perform the intraoral image processing method of any one of claims 1 to 12.

Description

Technical Field Disclosed embodiments relate to an intraoral image processing device and an intraoral image processing method, and more particularly, to an intraoral image processing device and method for automatically generating an outer surface of a target tooth that is a subject of a prosthesis, and an intraoral image processing method. Background Art Dental computer-aided design /computer-aided manufacturing (CAD/CAM) technology is widely used in dental treatment, particularly, prosthetics. The most important thing in dental treatment using CAD/CAM is to obtain precise three-dimensional (3D) data on a shape of an object such as a patient's teeth, gingiva, or a jawbone. When 3D data obtained from an object is used to perform dental treatment, accurate calculation may be performed by a computer. For example, methods such as computed tomography (CT), magnetic resonance imaging (MRI), and optical scanning may be used to obtain 3D data of an object in dental CAD/CAM treatment. When an intraoral image processing device obtains a 3D intraoral image from scan data, a user may select a target tooth that is a subject of a prosthesis from among teeth in the 3D intraoral image. However, in the prior art, there was the inconvenience that the user has to predict and directly work or modify a shape of an interdental area, etc., which was not possible to be scanned due to adjacent teeth adjacent to the target tooth. Accordingly, a shape of the prosthesis may be different from a shape of an actual tooth, and thus, the prosthesis may not fit the target tooth due to adjacent teeth, a patient may have a foreign body sensation, and it may take a long time to correct it. Accordingly, there is a need for a technology for automatically generating an outer surface of a target tooth similar to a shape of an actual target tooth, for an area that may not be scanned, such as an area between the target tooth that is a subject of a prosthesis and an adjacent tooth. US 2019/282344 A1 discloses dental CAD automation using deep learning. US 2013/226534 A1 discloses designing a virtual preparation and a virtual gingival. US 2015/100280 A1 discloses computer-implemented methods of designing dental restorations. US 2015/056576 A1 discloses a computer-implemented dental restoration design. KR 2019 0074062 A discloses a method for setting gingival line to design prosthesis. Disclosure Technical Problem An objective of a disclosed embodiment is to provide an intraoral image processing method for automatically generating, when a target tooth that is a subject of a prosthesis is selected in a three-dimensional (3D) intraoral data, a portion corresponding to a void area between the target tooth and at least one adjacent tooth adjacent to the target tooth, and an apparatus for performing an operation according to the intraoral image processing method. Technical Solution An intraoral image processing method, an intraoral image processing device, and a computer-readable recording medium according to the independent claims 1, 13 and 15 respectively are provided. Optional features are set out in the dependent claims. Advantageous Effects According to an intraoral image processing method, an apparatus for performing an operation according to the intraoral image processing method, and a computer-readable recording medium in which programs or instructions for performing the intraoral image processing method are stored according to a disclosed embodiment, a virtual margin line between a target tooth that is a subject of a prosthesis and a gingiva may be identified, and an outer surface of the target tooth may be generated by using the virtual margin line. Accordingly, even when there is a void area with no three-dimensional (3D) intraoral data between the target tooth and an adjacent tooth, the outer surface of the target tooth which is very similar to an outer surface of an actual tooth may be automatically generated. Description of Drawings In the intraoral image processing method according to an embodiment of the disclosure, the generating of the outer surface may include identifying a virtual target tooth by identifying a virtual bottom face corresponding to a bottom face of the target tooth based on the virtual margin line, and connecting the virtual bottom face to the target tooth, and generating the outer surface, based on the virtual target tooth and the virtual margin line. In the intraoral image processing method according to an embodiment of the disclosure, the identifying of the virtual margin line may include, for each of points of the target tooth, selecting at least one of the points of the target tooth, by identifying a point whose distance to at least one of points included in a boundary of the gingiva is equal to or less than a preset threshold value, based on data corresponding to the boundary of the gingiva and the target tooth in the 3D intraoral data, and identifying the virtual margin line by connecting the selected at least one po