Dental row image generation device, dental row image generation method, and program

Abstract

The dental arch image generation apparatus includes: an acquisition unit (51) for acquiring a photographic image of the surface of the dental arch and plaque inside the oral cavity irradiated with light in the wavelength range of blue light; a processing unit (52) for generating a plurality of second dental arch block images by performing white balance processing on each of a plurality of first dental arch block images, which are local dental arch images based on the photographed image; and a synthesis unit (53) for generating a dental arch image by synthesizing the plurality of second dental arch block images.

Description

Technical Field

[0001] This disclosure relates to a dental arch image generation apparatus, a dental arch image generation method, and a program. Background Technology

[0002] Patent Document 1 discloses an apparatus comprising: an excitation light emitting unit that emits excitation light for emitting fluorescence from dental plaque, lesions, etc.; and an illumination light emitting unit that emits illumination light for illuminating the periphery of dental plaque, lesions, etc., and the illumination unit is capable of simultaneously illuminating the illumination light and the excitation light. Furthermore, Patent Document 1 discloses that, in order to improve the visibility of dental plaque, lesions, etc., the amount of light emitted from the excitation light emitting unit is greater than the amount of light emitted from the illumination light emitting unit.

[0003] Existing technical documents Patent documents Patent Document 1: International Publication No. 2005 / 104926 Summary of the Invention

[0004] The problem that the invention aims to solve However, in a dental row image generation device that generates dental row images, it is desirable to generate dental row images with less disharmony.

[0005] Therefore, this disclosure provides a dental arch image generation apparatus, a dental arch image generation method, and a program capable of generating dental arch images with reduced disharmony.

[0006] Methods for solving problems One aspect of the present disclosure relates to a dental arch image generation apparatus comprising: an acquisition unit that acquires a photographic image of the surfaces of the dental arches and dental plaque within an oral cavity irradiated with light in the wavelength range including blue light; a processing unit that generates a plurality of second dental arch block images by performing white balance processing on each of a plurality of first dental arch block images based on the photographic image; and a synthesis unit that generates a dental arch image by synthesizing the plurality of second dental arch block images.

[0007] One aspect of this disclosure relates to a method for generating a dental arch image by acquiring a photographic image of the surface of the dental arch and plaque inside the oral cavity irradiated with light in the wavelength range containing blue light, generating a plurality of second dental arch block images by performing white balance processing on each of a plurality of first dental arch block images based on the photographic image, and generating a dental arch image by synthesizing the plurality of second dental arch block images.

[0008] One aspect of this disclosure relates to a program for causing a computer to perform the above-described method for generating images of the dental arch.

[0009] The effects of the invention According to one aspect of this disclosure, a dental arch image generation apparatus, etc., can be realized, capable of generating dental arch images with reduced disharmony. Attached Figure Description

[0010] Figure 1 This is a stereoscopic view of an intraoral camera in the dental arch image generation system described in the embodiment.

[0011] Figure 2 This is a schematic structural diagram of the dental row image generation system involved in the implementation method.

[0012] Figure 3 This is a block diagram illustrating the functional structure of the portable terminal involved in the embodiment.

[0013] Figure 4 This is a timing diagram illustrating the operation of the dental arch image generation system according to the embodiment.

[0014] Figure 5 This is a diagram illustrating the processing of the dental arch image generation system according to the embodiments.

[0015] Figure 6 This is a timing diagram illustrating the operation of a tooth row image generation system according to a modified example of the embodiment. Detailed Implementation

[0016] (How this disclosure came about) Before proceeding with this disclosure, the process of obtaining this disclosure will be explained.

[0017] Patent Document 1 discloses the use of LEDs (Light Emitting Diodes) with center wavelengths of 365nm, 405nm, or 470nm as the excitation light source. When photographing the affected area and its surroundings using such excitation light, the resulting image shows a tone in the plaque-free tooth area and the surrounding area that closely approximates the color of the excitation light. Therefore, the tone in the plaque-free tooth area and the surrounding area differs significantly from the actual tone, sometimes causing the user to perceive a sense of disharmony in the obtained image. For example, when using the obtained image to observe the condition of normal tissue surrounding the affected area or to explain it to the user, the significant difference from the actual tone can sometimes lead to a feeling of disharmony.

[0018] Furthermore, when adjusting the excitation light emitting section and the illumination light emitting section to improve the visibility of plaque, lesions, etc., the tonal reproducibility of each image obtained is low, and users sometimes feel that the obtained image is inconsistent.

[0019] Thus, in the device of Patent Document 1, there is room for improvement in generating dental arch images that reduce the sense of disharmony. Therefore, the inventors of this application have conducted in-depth research on dental arch image generation devices and the like that capable of generating dental arch images with reduced disharmony, and have invented dental arch image generation devices and the like shown below.

[0020] The dental arch image generation apparatus according to the first aspect of this disclosure includes: an acquisition unit that acquires a photographic image of the surface of the dental arch and plaque in the oral cavity irradiated with light in the wavelength range including blue light; a processing unit that generates a plurality of second dental arch block images by performing white balance processing on each of a plurality of first dental arch block images based on the photographic image; and a synthesis unit that generates a dental arch image by synthesizing the plurality of second dental arch block images.

[0021] Therefore, white balance adjustment can be performed on each of the multiple first dental row block images with appropriate gain. That is, the hue in the dental row image can be made closer to the actual hue. Thus, dental row images with reduced hue inconsistencies can be generated. In addition, since the white balance is adjusted before compositing, the outline of the teeth becomes clear, making compositing (e.g., stitching) easier.

[0022] Alternatively, for example, the dental arch image generation apparatus involved in the second method may be the same as the dental arch image generation apparatus involved in the first method, wherein it includes a detection unit that detects dental plaque in the dental arch image generated by the synthesis unit.

[0023] Therefore, by performing a single tartar detection and treatment, it is possible to generate an image of the dental arch that reduces the appearance of disharmony.

[0024] Alternatively, for example, the dental arch image generation apparatus involved in the third approach may be the dental arch image generation apparatus involved in the first approach, wherein it includes a detection unit that detects plaque in each of the plurality of second dental arch block images, and a synthesis unit that synthesizes the plurality of second dental arch block images that have been detected for plaque.

[0025] Therefore, it is also possible to use tartar areas (e.g., the outline of the tartar area) to synthesize multiple second dental arch block images. This allows for more accurate synthesis, thus enabling the generation of dental arch images with reduced inconsistencies caused by the synthesis process.

[0026] Alternatively, for example, the dental arch image generating apparatus involved in the fourth method may be the dental arch image generating apparatus involved in the second or third method, wherein it includes a generating unit for generating a dental arch image that highlights the plaque areas detected by the detection unit.

[0027] This allows for the highlighting of tartar areas in a dental arch image. For example, when such a dental arch image is presented to a user, the user can easily identify tartar areas.

[0028] Alternatively, for example, the dental arch image generating apparatus according to the fifth embodiment may be the dental arch image generating apparatus according to the fourth embodiment, wherein it includes a display unit that displays the dental arch image that emphasizes the tartar area.

[0029] This allows the system to present users with an image of the teeth that highlights areas of plaque. For example, by taking an image of the teeth after brushing and identifying plaque areas, the system can present users with images of unbrushed areas.

[0030] Alternatively, for example, the dental arch image generating device involved in the sixth method may be the dental arch image generating device involved in any of the first to fifth methods, wherein the plurality of first dental arch block images include images obtained by photographing the anterior teeth.

[0031] Therefore, it is possible to synthesize images obtained from taking pictures of teeth on the right side (e.g., right posterior teeth) to the anterior teeth, and images obtained from taking pictures of teeth on the left side (e.g., left posterior teeth) to the anterior teeth, using the anterior teeth as a reference. Thus, it is possible to generate images of a row of teeth from the right side to the left side.

[0032] Alternatively, for example, the dental arch image generating apparatus involved in the seventh method may be the dental arch image generating apparatus involved in any of the first to sixth methods, wherein the surface of the dental arch includes the side surface of the dental arch.

[0033] Therefore, as a dental arch image with reduced tonal inconsistency, it is possible to generate a dental arch image obtained by taking a side view of the dental arch.

[0034] Alternatively, for example, the dental arch image generating device involved in the eighth method may be a dental arch image generating device of any one of the first to sixth methods, wherein the surface of the dental arch includes the occlusal surface of the dental arch.

[0035] Therefore, as a dental arch image with reduced tonal inconsistency, it is possible to generate a dental arch image obtained by photographing the occlusal surface of the dental arch.

[0036] Alternatively, for example, the dental arch image generation apparatus according to the ninth method may be a dental arch image generation apparatus according to any one of the first to eighth methods, wherein it includes a saturation emphasis processing unit, which generates a converted image by converting the dental arch image into an HSV image, determines a specific pixel region containing one or more pixels of the plurality of pixels in the converted image that satisfy at least one of the following conditions: saturation within a first predetermined range, hue within a second predetermined range, and brightness within a third predetermined range, and generates a dental arch image with emphasized saturation by performing saturation emphasis processing on the specific pixel region in the dental arch image.

[0037] Therefore, specific pixel regions that constitute plaque areas are identified in the dental arch image, and saturation enhancement processing is applied to these specific pixel regions, thus enabling the generation of dental arch images that easily distinguish plaque areas (dental arch images with enhanced saturation S).

[0038] Alternatively, for example, the dental arch image generation apparatus according to the tenth method may be a dental arch image generation apparatus according to any one of the first to ninth methods, wherein it includes a shading display processing unit, which generates a converted image by converting the dental arch image into an HSV image, determines a specific pixel region where one or more pixels of a plurality of pixels in the converted image are located, satisfying at least one of the following: saturation within a first predetermined range, hue within a second predetermined range, and brightness within a third predetermined range, detects the cumulative level distribution of fluorescent substances accumulated in the dental plaque based on the brightness value in the specific pixel region of the converted image, and generates the dental arch image including shading display by performing shading image processing on the specific pixel region in the dental arch image corresponding to the detected cumulative level distribution of fluorescent substances.

[0039] Thus, for example, it is possible to generate images of rows of teeth that can inform the user of the concentration distribution of fluorescent substances.

[0040] Furthermore, one aspect of this disclosure relates to a method for generating a dental arch image by acquiring an image of the surfaces of the dental arches and plaque within the oral cavity illuminated by light in a wavelength range containing blue light. The method generates multiple second dental arch block images by performing white balance processing on each of a plurality of first dental arch block images based on the acquired image, and generates a dental arch image by synthesizing the plurality of second dental arch block images. Additionally, one aspect of this disclosure relates to a program for causing a computer to execute the aforementioned method for generating a dental arch image.

[0041] Therefore, it can achieve the same effect as the aforementioned dental arch image generation device.

[0042] Furthermore, these overall or specific methods can be implemented by non-transitory recording media such as systems, methods, integrated circuits, computer programs, or computer-readable CD-ROMs, or by any combination of systems, methods, integrated circuits, computer programs, or recording media. Programs can be pre-stored on the recording medium or supplied to the recording medium via wide area communication networks, including the Internet.

[0043] Furthermore, these figures are schematic diagrams, not rigorous illustrations. Therefore, factors such as the scale may not be consistent across different figures. Additionally, substantially identical structures are labeled with the same reference numerals across all figures, and redundant descriptions are omitted or simplified.

[0044] Furthermore, in this specification, terms indicating the relationship between identical elements, as well as numerical values ​​and ranges, are not only expressions with a rigorous meaning, but also imply ranges of substantial equivalence, such as including a difference of approximately a few percent (or approximately 10%).

[0045] Furthermore, in this specification, ordinal numbers such as "first" and "second" do not imply the quantity or order of constituent elements unless otherwise specified, but are used to distinguish them from each other to avoid confusion of the same constituent elements.

[0046] (Implementation Method) Hereinafter, the dental arch image generation system and method involved in this embodiment will be described with reference to... Figures 1 to 5 To explain.

[0047] [1. Structure of the dental arch image generation system] First, regarding the structure of the dental arch image generation system equipped with an intraoral camera involved in this embodiment, refer to... Figures 1 to 3 To explain. Figure 1 This is a perspective view of the intraoral camera 10 in the dental arch image generation system according to this embodiment.

[0048] like Figure 1 As shown, the intraoral camera 10 has a toothbrush-shaped housing that can be used with one hand. The housing includes: a head 10a that is located inside the user's mouth when photographing the teeth, a handle 10b that is held by the user, and a neck 10c that connects the head 10a and the handle 10b.

[0049] The imaging unit 21 captures images of the surfaces of the dentition and plaque within the oral cavity when illuminated with light in the wavelength range containing blue light. The surfaces of the dentition include at least one of the buccal (lateral) surfaces, the lingual (medial) surfaces, and the occlusal surfaces of the dentition.

[0050] The imaging unit 21 is assembled on the head 10a and neck 10c. The imaging unit 21 has an imaging element (not shown) and a lens (not shown) arranged on its optical axis LA.

[0051] The imaging element is, for example, a CMOS (Complementary Metal Oxide Semiconductor) sensor or a CCD (Charge Coupled Device) element, and an image of the teeth is formed through a lens. The imaging element outputs a signal (image data) corresponding to the image to the outside. The image captured by the imaging element is also recorded as an RGB image. Furthermore, the RGB image is a series of images obtained by illuminating the dental arch with blue light; for example, it can be a series of images obtained by photographing the lateral surfaces of the dental arch or the occlusal surfaces of the dental arch. The image series may include, for example, more than one image obtained by photographing the dental arch along the alignment direction (e.g., a time-series image). Additionally, the lateral surfaces of the dental arch can be lingual or buccal.

[0052] The imaging unit 21 may also include an optical filter that blocks colored light emanating from the illumination unit (illumination device) while allowing fluorescence emitted by dental plaque due to this light to pass through. In this embodiment, the imaging unit 21 may also include a blue light cutoff filter as an optical filter that cuts off the blue wavelength component of the light incident on the imaging element. When detecting dental plaque by illuminating teeth with light in the wavelength range containing blue light, if the wavelength range containing blue light is enhanced to enhance the excitation fluorescence of the dental plaque, the overall RGB image will have a blue tint because blue pixel values ​​dominate relative to red and green pixel values. As a countermeasure, a portion of the wavelength range containing blue light is cut off by the blue light cutoff filter before the light is incident on the imaging element. Alternatively, the imaging unit 21 may not include a blue light cutoff filter.

[0053] Furthermore, the intraoral camera 10 is equipped with a plurality of first LEDs 23A to fourth LEDs 23D as illumination units for illuminating light onto the teeth being photographed during imaging. The first LEDs 23A to fourth LEDs 23D illuminate colored light (e.g., a single color), which illuminates the dental plaque, causing the plaque to fluoresce. The first LEDs 23A to fourth LEDs 23D are, for example, blue LEDs, used to illuminate blue light containing a wavelength (an example of a specified wavelength) with a peak value of 405 nm. Moreover, the first LEDs 23A to fourth LEDs 23D are not limited to blue LEDs, as long as they are light sources capable of illuminating light within a wavelength range containing blue light.

[0054] Figure 2 This is a structural diagram outlining the dental arch image generation system according to this embodiment. In summary, the dental arch image generation system according to this embodiment is configured such that: the imaging unit 21 captures the fluorescence emitted by dental plaque relative to light from the illumination unit 23; and multiple images (e.g., a first dental arch block image described later) based on the captured RGB image are synthesized (merged) to generate a panoramic image of the type in which teeth are arranged in a horizontal row. A panoramic image is an image representing the state of at least a part (e.g., the entire mouth) of the user.

[0055] like Figure 2 As shown, the dental arch image generation system includes an intraoral camera 10 and a portable terminal 50.

[0056] The intraoral camera 10 includes a hardware unit 20, a signal processing unit 30, and a communication unit 40.

[0057] The hardware unit 20 is a physical element of the intraoral camera 10, and includes an imaging unit 21, a sensor unit 22, an illumination unit 23, and an operation unit 24.

[0058] The imaging unit 21 generates image data by photographing the teeth inside the user's mouth. Specifically, the imaging unit 21 generates image data by photographing the surfaces of the teeth and plaque inside the mouth illuminated by light of a predetermined wavelength that excites fluorescent substances contained in the plaque. The imaging unit 21 receives control signals from the camera control unit 31, performs actions such as shooting according to the received control signals, and outputs image data of the captured moving or still images to the image processing unit 32. The imaging unit 21 includes the aforementioned imaging element, optical filter, and lens. The image data is generated based on light passing through the optical filter. Furthermore, although the image data may depict images of multiple teeth, it is sufficient if at least one tooth is depicted.

[0059] Sensor unit 22 detects external light incident on the imaging area of ​​the RGB image. For example, sensor unit 22 detects whether external light is incident inside the oral cavity. Sensor unit 22 is disposed, for example, near imaging unit 21. For example, similar to imaging unit 21, sensor unit 22 may also be disposed on the head 10a of intraoral camera 10. In other words, when imaging unit 21 is taking pictures, sensor unit 22 is located inside the user's oral cavity.

[0060] The illumination unit 23 illuminates light onto the area photographed by the imaging unit 21 in one of the multiple areas of the oral cavity. As is known in quantitative visible light induced fluorescence (QLF method), it is known that when blue light is irradiated, the fluorescence (excitation fluorescence) of substances such as porphyrins excreted by bacteria in dental plaque is a reddish-pink color. In this embodiment, the illumination unit 23 irradiates blue light onto the area photographed by the imaging unit 21.

[0061] The lighting unit 23 has a plurality of LEDs, including the first LED 23A to the fourth LED 23D described above. These LEDs illuminate the shooting area from different directions, for example. This helps to suppress shadows in the shooting area.

[0062] Each of the plurality of first LEDs 23A to fourth LEDs 23D is configured to at least control dimming. Each of the plurality of first LEDs 23A to fourth LEDs 23D may also be configured to control both dimming and color adjustment. The plurality of LEDs of the plurality of first LEDs 23A to fourth LEDs 23D are arranged to surround the shooting unit 21.

[0063] The illumination unit 23 controls the illumination intensity (luminous intensity) according to the shooting area. The illumination intensity of each of the first LED 23A to the fourth LED 23D can be controlled to be the same or different from each other. In addition, there is no special limitation on the number of LEDs in the illumination unit 23; it can be one or more. Furthermore, the illumination unit 23 is not limited to having LEDs as a light source; it can also have other light sources.

[0064] The operation unit 24 receives operations from the user. The operation unit 24 may be composed of buttons, etc., but it may also be a structure that receives operations via voice, etc.

[0065] In addition, the hardware unit 20 may also include a battery (e.g., a secondary battery) for supplying power to the various components of the intraoral camera 10, a coil for wireless charging via an external charger connected to a commercial power source, and a driver required for at least one of the composition adjustment and focus adjustment.

[0066] The signal processing unit 30 includes functional units implemented by a CPU (Central Processing Unit) or MPU (Micro Processor Unit) that performs various processes described later, and a memory unit 35 storing programs such as ROM (Read Only Memory) and RAM (Random Access Memory) for enabling each functional unit to perform various processes. Specifically, the signal processing unit 30 includes a camera control unit 31, an image processing unit 32, a control unit 33, a lighting control unit 34, and a memory unit 35.

[0067] The camera control unit 31 is, for example, mounted on the handle 10b of the intraoral camera 10, and controls the imaging unit 21. The camera control unit 31 controls at least one of the aperture and shutter speed of the imaging unit 21 according to the control signal from the image processing unit 32.

[0068] The image processing unit 32, for example, is mounted on the handle 10b of the intraoral camera 10. It acquires RGB images (image data) captured by the imaging unit 21, performs image processing on the acquired RGB images, and outputs the processed RGB images to the camera control unit 31 and the control unit 33. Alternatively, the image processing unit 32 may output the processed RGB images to the memory unit 35, so that the processed RGB images are stored in the memory unit 35.

[0069] The image processing unit 32 is configured as a circuit, for example, to perform image processing such as noise reduction and contour enhancement on RGB images. Alternatively, noise reduction and contour enhancement can also be performed by the portable terminal 50.

[0070] Alternatively, the RGB image (the processed RGB image) output from the image processing unit 32 can be sent to the portable terminal 50 via the communication unit 40, and the received RGB image-based image (e.g., a dental arch image described later) can be displayed on the display unit 56 of the portable terminal 50. In this way, an RGB image-based image can be presented to the user.

[0071] The control unit 33 is a control device for the signal processing unit 30. The control unit 33 controls the components of the signal processing unit 30, for example, based on the detection results of external light, etc. by the sensor unit 22.

[0072] The lighting control unit 34, for example, is mounted on the handle 10b of the intraoral camera 10, and controls the lighting and extinguishing of the first LED 23A to the fourth LED 23D. The lighting control unit 34 is, for example, composed of circuitry. For instance, when a user performs an operation to start the intraoral camera 10 on the display 56 of the portable terminal 50, a corresponding signal is transmitted from the portable terminal 50 to the signal processing unit 30 via the communication unit 40. The lighting control unit 34 of the signal processing unit 30 illuminates the first LED 23A to the fourth LED 23D according to the received signal.

[0073] In addition to the program described above, the memory unit 35 also stores RGB images (image data) captured by the imaging unit 21. The memory unit 35 is implemented, for example, by a semiconductor memory such as ROM or RAM, but is not limited to this.

[0074] The communication unit 40 is a wireless communication module for wireless communication with the portable terminal 50. For example, the communication unit 40 is mounted on the handle 10b of the intraoral camera 10, and wirelessly communicates with the portable terminal 50 based on control signals from the signal processing unit 30. Wireless communication between the communication unit 40 and the portable terminal 50 follows existing communication standards such as WiFi (registered trademark) and Bluetooth (registered trademark). The intraoral camera 10 transmits RGB images to the portable terminal 50 via the communication unit 40, and the portable terminal 50 sends operation signals to the intraoral camera 10.

[0075] The portable terminal 50 displays, for example, a tartar area in an image of a dental arch including two or more teeth based on an RGB image. This RGB image is obtained by capturing a surface of the dental arch and tartar that fluoresces when light in a wavelength range containing blue light is irradiated onto the teeth. Furthermore, the portable terminal 50 functions as a user interface for a dental arch image generation system. The portable terminal 50 is an example of a dental arch image generation device.

[0076] Figure 3 This is a block diagram illustrating the functional structure of the portable terminal 50 according to this embodiment.

[0077] like Figure 3 As shown, the portable terminal 50 includes an acquisition unit 51, a processing unit 52, a synthesis unit 53, a detection unit 54, a generation unit 55, and a display unit 56. The portable terminal 50 includes a processor and a memory. The memory, such as ROM or RAM, is capable of storing programs executed by the processor. The acquisition unit 51, processing unit 52, synthesis unit 53, detection unit 54, and generation unit 55 are implemented by a processor or the like that executes the programs stored in the memory. The portable terminal 50 may also be implemented, for example, by a smartphone or tablet terminal capable of wireless communication.

[0078] The acquisition unit 51 acquires RGB images from the intraoral camera 10. Specifically, the acquisition unit 51 acquires images (image columns) generated by the imaging unit 21 that show multiple teeth. The RGB images are images obtained by the intraoral camera 10 capturing images of teeth that exhibit fluorescence reactions when illuminated with light of a wavelength range including blue light.

[0079] Here, the RGB image acquired by the acquisition unit 51 has an overall blue tint. This is because, when detecting plaque by illuminating teeth with light in the wavelength range containing blue light, the illumination unit 23 enhances the light in the wavelength range containing blue light to enhance the excitation fluorescence of the plaque. As a result, the blue pixel value (B) becomes dominant compared to the red pixel value (R) and the green pixel value (G). That is, a color shift occurs in the RGB image acquired by the acquisition unit 51. In this state, it is difficult to present the plaque adhesion state to the user in a way that is easy to understand. Therefore, as shown below, the portable terminal 50 performs a process to present the plaque adhesion state to the user in a way that is easy to understand by performing a prescribed image processing on the RGB image acquired by the acquisition unit 51.

[0080] The processing unit 52 generates multiple first tooth row block images as local tooth row images based on the RGB image (image column) generated by the imaging unit 21, and performs image processing on each of the multiple generated first tooth row block images to generate multiple second tooth row block images.

[0081] The first tooth row block image is obtained by cropping a defined area including the center of view from an image taken at a certain shooting position. Multiple first tooth row block images are images based on images from different shooting positions (or shooting directions).

[0082] Furthermore, the plurality of first dental block images each include an image of at least one tooth or interdental space. For example, the first dental block images may also be images of at least one tooth or interdental space taken from a frontal view. The sizes (image dimensions) of the first dental block images may be equal or different. Additionally, in each first dental block image, at least a portion of the tooth region projected in that first dental block image overlaps with a portion of the tooth region projected in at least one other first dental block image.

[0083] In addition, the RGB image can be the first dental block image itself, or it can be generated by dividing the RGB image in such a way that each part of the image is repeated.

[0084] Image processing includes at least WB (White Balance) processing. WB processing adjusts the color balance in an image by multiplying each of the R, G, and B components by a different gain (white balance gain). For example, WB processing adjusts the gain of at least two of the red, green, and blue components of an image of the object being processed in a manner that makes the average red pixel value of a plurality of pixels in a region of teeth in the first dental block image of the object being processed close to (e.g., equal to) the average green pixel value of a plurality of pixels in the region of teeth in the image of the object being processed.

[0085] This allows the teeth area to be displayed as white (achromatic). In other words, it easily reproduces the user's actual tooth color. Besides reducing image inconsistencies, this also makes it easier to emphasize areas of tartar.

[0086] The processing unit 52 performs WB processing on each of the multiple first tooth block images, assuming that the tooth regions reflected in the first tooth block image are white regions, thereby generating multiple second tooth block images. The processing unit 52 performs WB processing on each of the multiple first tooth block images based on the color (color information) of the tooth regions reflected in the first tooth block image. The processing unit 52 can perform WB processing based on the color (color information) of any tooth (e.g., the tooth in the center of the first tooth block image), or it can perform WB processing based on statistical values ​​(e.g., average, median, etc.) of the color (color information) of the tooth regions. For example, the processing unit 52 can also perform WB processing by multiplying the gain calculated based on the arbitrary tooth or statistical value by the entire tooth region.

[0087] Furthermore, the tooth region projected onto the first dental row block image can also be a region of natural teeth projected onto the first dental row block image. That is, the processing unit 52 may assume the region of natural teeth to be a white region (for example, based on the color (color information) of the region of natural teeth projected onto the first dental row block image) and perform WB processing. The region of natural teeth may be a region of natural teeth projected onto one tooth in the first dental row block image, a region of natural teeth projected onto a specified tooth, or a region of natural teeth projected onto multiple teeth. When using the region of natural teeth projected onto multiple teeth as a reference, statistical values ​​of the color (e.g., chromaticity) of the natural tooth regions of each of the multiple teeth may also be used for WB processing. The statistical value may be, for example, the average value, but may also be the maximum value, minimum value, most frequent value, median value, etc. Furthermore, when two or more teeth are projected onto the first dental row block image, statistical values ​​of the color (e.g., chromaticity) of the natural tooth regions of the teeth located at both ends of the image may also be used for WB processing. Therefore, it is possible to perform WB processing on each of the adjacent first dental row block images using at least the color (e.g., chromaticity) of the region of the natural tooth in the common tooth reflected in the adjacent first dental row block images. As a result, the tones of the adjacent first dental row block images after WB processing can be made similar, thus generating a dental row image with reduced tonal inconsistencies.

[0088] It is known that natural teeth emit excitation fluorescence from the dentin when illuminated with excitation light, and green fluorescence through the enamel. Furthermore, it is known that fillings (e.g., metal inlays) in caries treatment marks do not fluoresce under blue LED light and are captured by a camera at a relatively low brightness. Additionally, as mentioned above, it is known that plaque (plaster areas) fluoresces in a reddish-pink hue (excitation fluorescence) when illuminated with blue light. Therefore, the processing unit 52 can detect natural teeth other than caries treatment marks and plaque from the first dental arch block image.

[0089] Furthermore, the processing unit 52 can also identify the type of teeth (e.g., a specific tooth) contained in the image based on the first or second dental block image. Identifying the type of tooth can be done by identifying whether the tooth is an incisor, canine, or molar, or by identifying whether it is a central incisor, lateral incisor, canine, first premolar / second premolar / first molar / second molar / third molar (wisdom tooth). Additionally, the processing unit 52 can also identify which region of the oral cavity the tooth is located in (maxillary, mandibular, left or right). Furthermore, the method by which the processing unit 52 identifies the type of tooth is not particularly limited; for example, it can be a method using a machine learning model, a pattern matching method, or any other known method. A machine learning model is a learning model that learns by outputting the type of tooth reflected in an image when an image containing teeth is input. In the pattern matching method, images of teeth reflecting standard shapes can be used as a reference, or images of the teeth inside the user's oral cavity can be pre-captured as a reference. Alternatively, the processing unit 52 can present information about the teeth of the subject to be photographed to the user before shooting, and determine the teeth that appear in the image after presentation as the teeth of the subject to be photographed. Or, it can allow the user to input which teeth are included in the image, and determine that the type of teeth input is reflected in the image.

[0090] The compositing unit 53 generates a single image of a tooth row (panoramic image) containing multiple teeth by compositing multiple second tooth row block images processed by the processing unit 52. In this embodiment, the compositing unit 53 uses a stitching process to compose multiple processed images, but the compositing method is not limited to this. For example, the stitching process can also be performed using the outline of the teeth.

[0091] Furthermore, the stitching process here involves combining multiple images (in this case, multiple first dental row block images) with overlapping regions to generate more than one dental row image. In the stitching process, firstly, the multiple first dental row block images are arranged on a two-dimensional plane with overlapping portions. Then, the multiple first dental row block images are scaled (magnification), positioned, and oriented so that at least a portion of the feature points and surface points are visible at the same location on the two-dimensional grid. In this way, the multiple first dental row block images are aligned with their arrangement. That is, the multiple first dental row block images are arranged to represent a series of adjacent teeth, and in a manner that ensures consistent tooth position.

[0092] Furthermore, any type of feature detection algorithm, including Scale Invariant Feature Transform (SIFT) or Supersonic Feature Rendering (SURF), can be used as the feature detection algorithm for detecting feature points. In this embodiment, feature points can also be set on the contour portion of the tooth region. In addition, by measuring the distance between the focal points of two viewpoints that have captured images of the first tooth row blocks containing overlapping portions, the angle of the optical axis of each viewpoint is extracted, and the position of the surface point can be calculated based on the measure of the triangle of the shared position in the image.

[0093] Furthermore, the following description illustrates an example of the synthesis unit 53 generating an image of a row of teeth from the left posterior teeth to the right posterior teeth through synthesis. However, it is not limited to this; an image of a row of teeth containing two or more teeth or other portions of teeth can be generated. In this case, the synthesis unit 53 may also include information related to the type of the teeth or their position within the oral cavity in the image of the row of teeth. This allows the user to be informed which region of the oral cavity the image of is being presented with. Furthermore, the type of teeth or their position within the oral cavity (e.g., maxillary, mandibular, left and right regions) is determined by the processing unit 52.

[0094] The detection unit 54 performs plaque (platter area) detection on the image that has undergone WB processing (an example of an image based on a captured image). In this embodiment, the detection unit 54 performs plaque detection based on the color information of the tooth areas in the tooth row image generated by the synthesis unit 53. The color information includes lightness (V), hue (H), and saturation (S). The detection unit 54 detects plaque, for example, based on lightness (V). The detection unit 54 detects areas with lightness (V) of a threshold or higher as plaque areas.

[0095] Alternatively, the detection unit 54 may take the tooth row image that has undergone WB processing as input and use a machine learning model that has learned in a way that outputs the plaque (platform area) reflected in the tooth row image to detect the plaque (platform area) reflected in the tooth row image.

[0096] The generation unit 55 is a processing unit for generating a dental arch image (e.g., a first dental arch image or a second dental arch image described later) that highlights the tartar areas detected by the detection unit 54. The generation unit 55 highlights the detected tartar areas in each of the dental arch image or multiple second dental arch block images generated by the synthesis unit 53. For example, the generation unit 55 overlaps and highlights the tartar areas in each of the dental arch image or multiple second dental arch block images.

[0097] The display unit 56 is a display device provided in the portable terminal 50, which displays the image generated by the image generation unit 55. The display unit 56 may also be implemented using, for example, a liquid crystal display panel.

[0098] Furthermore, the detection unit 54 and the generation unit 55 can also function as saturation enhancement processing units. For example, the detection unit 54 can generate a converted image by converting a dental arch image (e.g., a first dental arch image or a second dental arch image) synthesized by the synthesis unit 53 and subjected to WB processing into an HSV image, and determine a specific pixel region containing at least one pixel among a plurality of pixels in the converted image that satisfies at least one of the following: saturation S within a first predetermined range (e.g., 30 or more and 80 or less in 8-bit representation), hue H within a second predetermined range (e.g., 140 or more and 170 or less in 8-bit representation), and lightness V within a third predetermined range (e.g., 100 or more and 180 or less in 8-bit representation). Additionally, the generation unit 55 can also generate a dental arch image with enhanced saturation S by performing saturation enhancement processing on a specific pixel region in the dental arch image. For example, an HSV image can be generated by converting the color space of the dental arch image to the HSV space. Furthermore, the display unit 56 can also display the dental arch image that has undergone saturation enhancement processing.

[0099] The first, second, and third specified ranges can be determined by comparing the actual plaque area, the tooth area, and the HSV image, and are not limited to the numerical ranges mentioned above. For example, the ranges of values ​​for lightness (V), hue (H), and saturation (S) can be determined by applying a plaque stain and comparing the staining effect with the degree of staining.

[0100] Furthermore, the detection unit 54 and the generation unit 55 can also function as a density display processing unit that performs density image processing corresponding to the concentration distribution (cumulative level distribution) of fluorescent substances. For example, the detection unit 54 can detect the concentration distribution of fluorescent substances accumulated in dental plaque based on the brightness V value in a specific pixel region of the converted image. In addition, the generation unit 55 can generate a density display of a dental arch image by performing density image processing on a specific pixel region of the dental arch image corresponding to the detected concentration distribution of fluorescent substances.

[0101] As blue light passes through the layers of plaque, the porphyrins in the plaque are excited, producing red fluorescence. Furthermore, it is believed that the fluorescence intensity does not reflect the current bacterial flora, but rather the accumulation of fluorescent substances (porphyrins). That is, the more fluorescent substances accumulate, the stronger the red fluorescence. In other words, as plaque matures, the level of porphyrin accumulation increases. Therefore, the fluorescence intensity of mature plaque is stronger than that of early plaque.

[0102] The detection unit 54 detects the cumulative level (concentration or density) of fluorescent substances by comparing the intensity of red fluorescence per unit area of ​​the tartar region.

[0103] As described above, tartar regions can be extracted from one or more pixels in an HSV image that satisfy at least one of the following conditions: saturation S within a first specified range, hue H within a second specified range, and lightness V within a third specified range.

[0104] Furthermore, in images that have undergone WB processing, in tartar areas, the lightness V is determined by the value of R, independent of hue (H) and saturation (S).

[0105] Furthermore, porphyrins, known as fluorescent substances within dental plaque, have fluorescence wavelengths ranging from 600 nm to 740 nm, with a peak fluorescence wavelength of 630 nm. This means that the concentration of accumulated porphyrins in the dental plaque region can be evaluated by detecting the brightness (V) value of the HSV image of the plaque region.

[0106] [2. Actions of the dental arch image generation system] Next, regarding the operation of the dental arch image generation system constructed as described above, refer to... Figure 4 as well as Figure 5 To explain. Figure 4 This is a sequence diagram illustrating the operation (dental row image generation method) of the dental row image generation system according to this embodiment. Figure 4 The processing shown is performed by the portable terminal 50. Furthermore, Figure 4 The processing shown is, for example, real-time processing, performed whenever one or more frames of image data are obtained. Figure 5 This diagram illustrates the processing of the dental arch image generation system according to this embodiment. Furthermore, in Figure 5 In the image, color cast is represented by a diagonal shading line.

[0107] like Figure 4 As shown, the user generates image data by taking pictures of their teeth and gums inside their mouth using an intraoral camera 10 (S101). This image data is, for example, obtained by taking pictures of teeth that fluoresce when illuminated with light in a wavelength range containing blue light.

[0108] Next, the communication unit 40 of the intraoral camera 10 sends the captured image data to the portable terminal 50, and the acquisition unit 51 of the portable terminal 50 acquires the image data (S102). The image data can be a moving image or one or more still images. Furthermore, if the image data is a moving image or multiple still images, the image data can be sent for each frame of the moving image or each still image. Alternatively, if the image data is a moving image, the image data can be sent for multiple frames.

[0109] In addition, image data can be transmitted in real time or collected and transmitted after a series of shots (such as shots of all the teeth inside the mouth).

[0110] The portable terminal 50 performs image processing on the received image data (S103). In step S103, the processing unit 52 of the portable terminal 50 performs WB processing on each of the first tooth row block images based on the image data.

[0111] like Figure 5 As shown in (a) and (b), the processing unit 52 generates multiple second tooth row block images P11 to P15 by performing WB processing on each of the multiple first tooth row block images P1 to P5. Alternatively, the processing unit 52 may perform WB processing on each of the multiple first tooth row block images P1 to P5 based on the color information of the tooth region of that first tooth row block image.

[0112] Refer again Figure 4 Next, the synthesis unit 53 of the portable terminal 50 synthesizes multiple second tooth row block images after image processing (S104).

[0113] like Figure 5 As shown in (b) to (d), the synthesis unit 53 performs a stitching process on the second tooth row block images P11, P12, and P13 to generate a first tooth row image P21 containing at least a portion of the second tooth row block images P11 and P12, and the second tooth row block image P13. Furthermore, the synthesis unit 53 performs a stitching process on the second tooth row block images P13, P14, and P15 to generate a first tooth row image P22 containing at least a portion of the second tooth row block image P13, and the second tooth row block images P14 and P15. The first tooth row images P21 and P22 are repeated images of at least a portion of the tooth region. Figure 5 In the example, at least a portion of the tooth region in the second tooth block image P13 is repeated in the first tooth row images P21 and P22.

[0114] Furthermore, the processing unit 52 performs the stitching process by including the central portion of the viewpoint of each of the synthesized second tooth row block images in the first tooth row image. Taking the first tooth row image P21 as an example, the processing unit 52 performs the stitching process by including the central portion of the viewpoint of each of the second tooth row block images P11-P13 in the first tooth row image P21. The resulting first tooth row image P21 is an image where each tooth is illuminated from the front, thus creating an image where shadows are difficult to form and the spaces between teeth are easily visible.

[0115] Here, the second dental row block image P13 may also include images of the two lower anterior teeth, for example, an image of the interdental space between the two anterior teeth. In this case, the first dental row image P21 may, for example, be a panoramic image reflecting from the left posterior teeth to the anterior teeth, and the first dental row image P22 may, for example, be a panoramic image reflecting from the right posterior teeth to the anterior teeth.

[0116] Furthermore, the image of the interdental space containing the front teeth can be, for example, an image captured after a broadcast such as "Please take a picture of the front teeth" is made when the imaging unit 21 takes a picture, or an image obtained by the user or others inputting "It is an image of the front teeth".

[0117] Furthermore, there is no particular limitation on the number of images of the first row of teeth generated by the compositing unit 53; it can be three or more.

[0118] Then, the synthesis unit 53 generates a second dental arch image P30 by performing a stitching process on the two first dental arch images P21 and P22. The second dental arch image P30 is a panoramic image obtained by synthesizing multiple second dental arch block images P11 to P15. The second dental arch image P30 is a panoramic image reflecting at least a portion of the dental arch in the user's oral cavity, for example, it may be a panoramic image reflecting from the user's left posterior teeth to the right posterior teeth.

[0119] Furthermore, the synthesis unit 53 can also directly generate the second dental row image P30 based on multiple second dental row block images P11~P15. That is, it is also possible not to generate the first dental row images P21 and P22.

[0120] Refer again Figure 4 Next, the detection unit 54 of the portable terminal 50 detects dental plaque on the second dental arch image P30 (S105). The detection unit 54 detects the presence or absence of dental plaque, but it can also detect, for example, the concentration distribution of fluorescent substances, i.e., the accumulation level of dental plaque.

[0121] Next, the generation unit 55 of the portable terminal 50 generates an image that highlights the tartar-covered areas detected by the detection unit 54 (S106). In this embodiment, the generation unit 55 generates an image that overlays the highlighted tartar areas onto the second dental arch image P30, but it may also generate a dental arch image that includes shades corresponding to the concentration distribution of the fluorescent substance.

[0122] Next, the display unit 56 of the portable terminal 50 displays the image generated by the generation unit 55 (S107).

[0123] By using such a dental arch image generation system, users can capture images of their own oral cavity using an intraoral camera 10 and check the state of their oral cavity displayed on a portable terminal 50 using panoramic images. Furthermore, by showing the concentration distribution of fluorescent substances in the displayed panoramic images, users can easily check the health status of their own teeth.

[0124] In addition, the portable terminal 50 performs white balance processing, thus enabling the generation of a second row of teeth image P30 (e.g., highlighted) with overlapping plaque areas, independent of the light color irradiated by the illumination section 23 of the intraoral camera 10.

[0125] Additionally, the portable terminal 50 can generate a three-dimensional model of multiple teeth inside the oral cavity based on multiple captured image data. Furthermore, the portable terminal 50 can also display images based on the generated three-dimensional model.

[0126] Alternatively, instead of detecting plaque on the second dental arch image P30, the detection unit 54 can detect plaque on the first dental arch images P21 and P22.

[0127] Furthermore, an example of processing images of teeth using a portable terminal 50 has been described here, but this processing can also be performed partially or entirely by an intraoral camera 10.

[0128] (Modifications of the implementation method) The following section discusses the dental arch image generation system involved in this variation, referring to... Figure 6 This will be explained in more detail. Furthermore, the following focuses on the differences from the implementation method; content that is the same as or similar to the implementation method will be omitted or simplified. Additionally, the structure of the dental arch image generation system according to this modification can also be the same as the implementation method. Hereinafter, the reference numerals of the dental arch image generation system according to the implementation method will be used for explanation.

[0129] Figure 6 This is a timing diagram illustrating the operation (dental row image generation method) of the dental row image generation system according to this modification. The detection unit 54 according to this modification differs from the detection unit 54 according to the embodiment in that it performs plaque detection on each of the plurality of second dental row block images. That is, the detection unit 54 performs plaque detection on the image before it is synthesized by the synthesis unit 53.

[0130] like Figure 6 As shown, the detection unit 54 of the portable terminal 50 detects dental plaque in each of the multiple second tooth row block images P11 to P15, which have undergone image processing (S105). The detection unit 54 detects the presence or absence of dental plaque, but it can also detect, for example, the concentration distribution of fluorescent substances, i.e., the accumulation level of dental plaque.

[0131] Next, the generation unit 55 of the portable terminal 50 generates an image that highlights the plaque-covered areas detected by the detection unit 54 (S106). In this modified example, the generation unit 55 generates images by overlaying the highlighted areas of plaque-covered regions detected by the detection unit 54 onto multiple second dental arch block images P11 to P15. It can also be said that the generation unit 55 generates multiple second dental arch block images P11 to P15 with the plaque-covered areas highlighted.

[0132] Next, the synthesis unit 53 of the portable terminal 50 synthesizes multiple second tooth row block images P11~P15 after highlighting the tartar area (S104). Thus, the synthesis unit 53 can also use the tartar area as a feature point during suturing.

[0133] (Other implementation methods) The dental arch image generation system according to the embodiments of the present disclosure has been described above, but the present disclosure is not limited to these embodiments.

[0134] For example, in the above embodiments, an example using an intraoral camera 10 primarily for photographing teeth has been described, but the intraoral camera 10 could also be an intraoral care device equipped with a camera. For example, the intraoral camera 10 could also be an intraoral cleaning machine equipped with a camera.

[0135] Furthermore, in the above embodiments, portable terminal 50 is cited as an example of the information terminal for the user; however, the information terminal may also be a desktop information terminal.

[0136] Furthermore, in the above embodiments, the multiple tooth block images may be images captured after the position or type of teeth has been broadcast when the imaging unit 21 takes pictures, or images obtained by the user inputting which position of the teeth is being photographed.

[0137] Furthermore, the processing units included in the dental arch image generation system described in the above embodiments are typically implemented as LSIs (Laser Sensors) of integrated circuits. They can be implemented individually on a single chip, or in a manner that includes some or all of them on a single chip.

[0138] Furthermore, integrated circuitry is not limited to LSIs; it can also be achieved through dedicated circuits or general-purpose processors. Alternatively, it can utilize FPGAs (Field Programmable Gate Arrays) that are programmable after LSI manufacturing, or reconfigurable processors that can reconfigure the connections and settings of the circuit cells within the LSI.

[0139] Furthermore, in the above-described embodiments, each component can be constructed using dedicated hardware, or it can be implemented by executing software programs suitable for each component. Each component can also be implemented by a program execution unit such as a CPU or processor reading and executing software programs recorded on a recording medium such as a hard disk or semiconductor memory.

[0140] Furthermore, the segmentation of functional blocks in a block diagram is one example. Multiple functional blocks can also be implemented as a single functional block, or a single functional block can be divided into multiple functional blocks, or some functions can be moved to other functional blocks. Additionally, the functions of multiple functional blocks with similar capabilities can be processed in parallel or time-sharing by a single piece of hardware or software.

[0141] Furthermore, the portable terminal 50 described in the above embodiments can be implemented as a single device or by multiple devices. When the portable terminal 50 is implemented by multiple devices, the various components of the portable terminal 50 can be arbitrarily distributed among the multiple devices. For example, at least some of the functions of the portable terminal 50 can also be implemented by the intraoral camera 10 (e.g., the signal processing unit 30). When the portable terminal 50 is implemented by multiple devices, the communication method between these multiple devices is not particularly limited; it can be wireless communication or wired communication. Furthermore, wireless and wired communication can also be combined between the devices.

[0142] Alternatively, this disclosure can also be implemented as a method for generating dental arch images executed by a dental arch image generation system. This disclosure can also be implemented as including an intraoral camera, a portable terminal, or a cloud server within the dental arch image generation system.

[0143] Furthermore, the order of the steps in the execution sequence diagram is illustrative for the purpose of explaining this disclosure, and may be in a different order than described above. Additionally, some of the steps described above may be executed simultaneously (in parallel) with other steps.

[0144] Alternatively, this disclosure can also be implemented by having a computer execute... Figure 4 or Figure 6 The method for generating images of dental arches shown includes a computer program with characteristic steps.

[0145] Alternatively, the program can also be a program for causing a computer to execute. Another aspect of this disclosure can be a computer-readable, non-transitory recording medium on which such a program is recorded. For example, the recording medium containing such a program can be distributed or circulated. For instance, the distributed program can be installed on a device having another processor, causing the processor to execute the program, thereby enabling the device to perform the aforementioned processes.

[0146] The dental arch image generation system and the like, based on the embodiments, have been described above in one or more ways, but this disclosure is not limited to these embodiments. As long as they do not depart from the spirit of this disclosure, various modifications to this embodiment that can be conceived by those skilled in the art, and ways of constructing by combining the constituent elements of different embodiments, may also be included within the scope of one or more embodiments.

[0147] Industrial availability This disclosure can be applied to a dental arch image generation system.

[0148] Explanation of reference numerals in the attached figures 10. Intraoral camera 10a Head 10b Handle section 10c Neck 20 Hardware Department 21 Filming Department 22 Sensors 23 Lighting Department 23A First LED 23B Second LED 23C Third LED 23D Fourth LED 24 Operations Department 30 Signal Processing Department 31 Camera Control Unit 32 Image Processing Department 33 Control Department 34 Lighting Control Department 35. Memory Section 40 Ministry of Communications 50 Portable Terminal (Dental Row Image Generation Device) 51 Acquisition Department 52 Processing Department 53 Synthesis Department 54. Detection Department (Saturation Emphasis Processing Department, Concentration and Depth Display Processing Department) 55 Generation Unit (Saturation Emphasis Processing Unit, Darkness and Lightness Display Processing Unit) 56 Display Section Images of the first row of teeth, P1, P2, P3, P4, and P5. Images of the second tooth row (P11, P12, P13, P14, P15) Images of the first row of teeth on pages 21 and 22 (dental row images) Image of the second row of teeth (P30)

Claims

1. A dental arch image generation apparatus, wherein, Possessing: an acquisition section that acquires a captured image obtained by capturing a surface of a dental arch and dental plaque in an oral cavity that is irradiated with light containing a wavelength range of blue light; a processing section that generates a plurality of second dental arch block images by performing white balance processing on each of a plurality of first dental arch block images, which are dental arch images based on a local part of the captured image; and a combining section that generates a dental arch image by combining the plurality of second dental arch block images.

2. The dental arch image generation apparatus according to claim 1, wherein a detection section that performs detection of dental plaque on the dental arch image generated by the combining section is possessed.

3. The dental arch image generation apparatus according to claim 1, wherein a detection section that performs detection of dental plaque on each of the plurality of second dental arch block images is possessed, the combining section combines the plurality of second dental arch block images on which detection of dental plaque is performed.

4. The dental arch image generation apparatus according to claim 2 or 3, wherein a generation section that generates the dental arch image in which a dental plaque region detected by the detection section is emphasized is possessed.

5. The dental arch image generation apparatus according to claim 4, wherein a display section that displays the dental arch image in which the dental plaque region is emphasized is possessed.

6. The dental arch image generation apparatus according to any one of claims 1 to 3, wherein the plurality of first dental arch block images include an image captured by capturing a front tooth.

7. The dental arch image generation apparatus according to any one of claims 1 to 3, wherein the surface of the dental arch includes a side surface of the dental arch.

8. The dental arch image generation apparatus according to any one of claims 1 to 3, wherein the surface of the dental arch includes a biting surface of the dental arch.

9. The dental arch image generation apparatus according to any one of claims 1 to 3, wherein a saturation emphasis processing section that generates a converted image by converting the dental arch image into an HSV image, determines a specific pixel region in which one or more pixels that satisfy at least one of a saturation being within a first prescribed range, a hue being within a second prescribed range, and a lightness being within a third prescribed range among a plurality of pixels possessed by the converted image are located, and generates the dental arch image in which saturation is emphasized by performing saturation emphasis processing on the specific pixel region in the dental arch image is possessed.

10. The dental arch image generation apparatus according to any one of claims 1 to 3, wherein The device includes a shading display processing unit that generates a converted image by converting the dental arch image into an HSV image, determines a specific pixel region containing one or more pixels among a plurality of pixels in the converted image that satisfy at least one of the following conditions: saturation within a first predetermined range, hue within a second predetermined range, and brightness within a third predetermined range, detects the cumulative level distribution of fluorescent substances accumulated in the dental plaque based on the brightness value in the specific pixel region of the converted image, and generates a dental arch image containing shading display by performing shading image processing on the specific pixel region in the dental arch image corresponding to the detected cumulative level distribution of fluorescent substances.

11. A method for generating images of dental arches, wherein, Images of the surfaces of the teeth and dental plaque inside the mouth are obtained by photographing light in the wavelength range containing blue light. Multiple second tooth row block images are generated by performing white balance processing on each of the multiple first tooth row block images based on local tooth row images of the captured images. A tooth row image is generated by synthesizing the multiple second tooth row block images.

12. A program for causing a computer to perform the dental arch image generation method of claim 11.

Images