JP2015066192A - Tooth colorimetric method, tooth colorimetric device, and tooth colorimetric program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tooth colorimetric method allowing rapid measurement of a color of a tooth and allowing early acquisition of a result.SOLUTION: A device (1) includes imaging means (11), storage means (13), and arithmetic means (10). By use of the device (1), a plurality of color samples having different colors are photographed by the imaging means, signals from the imaging means (11) are calculated by the arithmetic means to quantify the colors, and they are stored in the storage means as respective reference values of the plurality of color samples, a color is quantified and digitalized from an immediate video of a tooth that is a measurement target by the arithmetic means to set it to a measurement value, the reference values and the measurement value are compared, and the sample of the reference value closest to the measurement value is extracted.

Description

  The present invention relates to a method, an apparatus, and a program for measuring the color of a patient's tooth in advance in order to determine a color, which is one of information required when producing a prosthesis in the dental field.

  In dentistry, a dental prosthesis such as a crown is used for dental treatment, and the function of a tooth lost due to a disease or the like is artificially restored. It is known that teeth have a function of so-called mastication and the like, and the shape, arrangement, and color of the teeth affect the impression on the human face. Therefore, when producing a dental prosthesis, the color of the dental prosthesis must also be determined appropriately. For example, if a dental prosthesis is too black compared to other natural teeth, it is very unnatural.

  A shade guide is prepared for this purpose. The shade guide is a set of multiple dental prosthesis samples that are slightly different in color, and when determining the color of the dental prosthesis, the sample is taken out and compared with the patient's teeth. Repeat to search for and select a sample with a color close to the color of the tooth. And the dental prosthesis produced based on this color sample is colored.

  However, selecting an appropriate color from the shade guide is troublesome because the comparison and the selection of the sample are repeated, and the selection itself has been made sensuously by human color vision, so it is not always stable and appropriate. It could not be said that a certain color was selected. On the other hand, Patent Document 1 discloses an apparatus that quantitatively grasps the color of a tooth and objectively compares it with a color sample.

JP 2007-190371 A

  However, in the apparatus described in Patent Document 1, it is necessary to take an image of a tooth once, connect it to another apparatus, read the image, and separately measure the color. According to this, since the apparatus becomes large-scale and the result cannot be seen immediately, there is a possibility that the dialogue with the patient does not proceed smoothly. In recent years, especially for an aging society, there has been an increasing demand for a rapid treatment while communicating with patients, and prompt acquisition of results is required.

  Then, this invention makes it a subject to provide the tooth colorimetry method which can measure a tooth color rapidly and can obtain a result quickly. Further, a tooth color measuring device and a tooth color measuring program using the same are provided.

  The present invention will be described below. Here, for ease of understanding, reference numerals attached to the drawings are described in parentheses, but the present invention is not limited thereto.

  The invention described in claim 1 uses an apparatus (1) including an imaging means (11), a storage means (13), and a calculation means (10), and photographs a plurality of color samples having different colors with the imaging means. The signal from the image pickup means (11) is quantified by the calculation means (10), and this is stored in the storage means (13) as each reference value of a plurality of color samples, and an immediate image of the tooth to be measured is obtained. Is a tooth colorimetric method in which a color is quantitatively converted into a numerical value by a calculation means (10) and used as a measured value, and a sample of the closest reference value is extracted by comparing the reference value with the measured value.

  According to the second aspect of the present invention, the color is quantified from the imaging means (11) having an element for converting the photographed video into an electrical signal, and a plurality of color samples of different colors photographed by the imaging means (11). These are used as reference values for each color sample, and the color is quantitatively converted into a measurement value from the immediate image of the tooth to be measured, and the reference value is compared with the measurement value. A computing means (10) for extracting a sample, a storage means (13) for storing the computation result by the computing means (10), and a display means (15) for displaying at least a part of the result computed by the computing means (10). ).

  According to a third aspect of the present invention, in the tooth color measuring device (1) according to the second aspect, the image pickup means (11), the calculation means (10), the storage means (13), the display means (15), and the communication All the means (16) are housed in one housing.

  According to a fourth aspect of the present invention, a plurality of color samples having different colors are acquired by the image pickup means (11), the color is quantified by the calculation means (10), and this is stored as a reference value for each of the plurality of color samples. A step of storing in the means (13), a step of quantitatively quantifying the color from the immediate image of the tooth to be measured by the calculation means (10) and using this as a measurement value, and a reference value in the calculation means (10) And a step of extracting the sample of the closest reference value by comparing the measured value with the measured value.

  According to the present invention, since a result is obtained by measuring a color from an immediate (real-time) image of a tooth, the result can be provided to the patient on the spot.

It is a figure explaining the structure of a tooth colorimetry apparatus. It is a figure explaining the flow of a tooth colorimetry method and the program for it. It is a figure explaining the area | region of a colorimetry.

  The above-described operation and gain of the present invention will be clarified from the embodiments described below. Hereinafter, the present invention will be described based on embodiments shown in the drawings. However, the present invention is not limited to these forms.

  FIG. 1 is a diagram for explaining one embodiment, and is a diagram for conceptually explaining the configuration of the tooth color measuring device 1. The tooth colorimetric apparatus 1 includes a calculation unit 10 that also functions as a colorimetry unit, an imaging unit 11, an input unit 12, a storage unit 13, a RAM 14, a display unit 15, and a communication unit 16.

  The calculation means 10 is constituted by a so-called CPU (central operator), is connected to each constituent member provided in the tooth color measuring device 1, and calculates and controls them based on a program stored in the storage means 13. It is means to do. The calculation means 10 also functions as a color measurement means that executes various programs stored in the storage means 13 and performs color measurement calculations based on the acquired video data and program. A specific color measurement mode will be described later.

The imaging means 11 includes an imaging lens and an imaging element.
The imaging lens forms a tooth image as a subject and irradiates the imaging element.
The image sensor converts light into an electrical signal for each of RGB elements based on the irradiated light, and outputs this as an image signal. Although the kind of this image pick-up element is not specifically limited, For example, CCD and CMOS can be mentioned.
The electric signal obtained by the image sensor is transmitted to the calculation means 10 and processed based on the program by the calculation means 10 functioning as a color measurement means.

  The input means 12 is a means for the user to instruct, for example, the start / end of tooth color measurement, or to input color measurement and imaging conditions. Examples of this include an operation button. Also, an input means using a so-called touch panel that has become particularly widely used in recent years may be applied. A command from the input unit 12 is transmitted as an electric signal to the calculation unit 10, and the calculation unit 10 calculates based on a program and issues a command to each component as necessary.

  The storage unit 13 is a unit that functions as a storage medium in which a program serving as a basis for the calculation unit 10 is stored. As one of the basis programs, a program for causing the calculation means 10 to function as a color measurement means is included. In addition, the generated various data may be stored in the storage unit 13.

  The RAM 14 is a structural member that functions as a work area for the computing means 10 or a temporary data storage means. The RAM 14 can be configured by SRAM, DRAM, flash memory, or the like, and is similar to a known RAM.

  The display means 15 is a means for displaying matters to be conveyed to the user among the results calculated by the calculation means 10. This includes a so-called image display device.

  The communication means 16 is means for communicating information to a corresponding device among the results calculated by the calculation means 10. This includes a so-called wireless communication device.

  It is preferable that the tooth colorimetric apparatus 1 as described above is an embodiment in which all of the constituent members are housed in one housing. As a result, the apparatus can be simply configured, and the tooth colorimetric apparatus 1 is easier to use. An example of this is a portable terminal. Of the above-described configurations, portable terminals are often provided in advance except for a program for causing the calculation means to function as the color measurement means. Accordingly, the tooth colorimetric device 1 can be obtained by installing the program in a portable terminal. This eliminates the need for a large-scale apparatus configuration as in the prior art.

  Next, one mode of the method for measuring the color of a patient's tooth using the tooth color measuring device 1 (tooth color measuring method S10) will be described. Here, for the sake of clarity, an example using the tooth colorimetric device 1 will be described. However, the present invention is not limited to this, and any other device can be used as long as it enables a method including the following points. Color may be performed.

  The flow of the tooth colorimetry method S10 is shown in FIG. The tooth measurement method S10 includes a calibration process S11, a measurement target part determination process S12, a color measurement process S13, a comparison determination process S14, a result output process S15, and a continuous measurement determination process S16. Each process will be described below. It should be noted that the matters performed in each of these steps are advanced by the calculation means 10 as the color measurement means based on the program stored in the storage means 13. Therefore, the tooth color measurement method S10 follows the flow of the program.

In the calibration process S11, the actual shade guide or a printed material in which the shade guide color (lightness, saturation, hue) is reproduced is imaged by the imaging means 11, and the color is quantified and registered as a reference value. Since the shade guide and the printed material are composed of a plurality of color samples that are slightly different in color, there are a plurality of reference values corresponding thereto.
Color quantification is not particularly limited, but it is divided into a plurality of gradations in RGB or HSV (Hue, Saturation, Value) color space, and the gradations are divided into the gradations. Can be quantified. Since the reference color sample has a plurality of types of color tones, the color is quantified for each color sample and recorded in the storage means 13 as a reference value.
The calibration process S11 does not necessarily need to be performed every time the tooth is colorimetrically measured. If this is performed once and recorded, it can be omitted from the next time.

  The measurement target part determination step S12 is a process of determining the position and range of the part to be actually measured. As shown in FIG. 3, the tooth color measuring device 1 forms a predetermined area A on the tooth and measures the color at this part. The position and size of the area A can be changed. Accordingly, as described later, according to the present invention, the result can be presented to the patient while measuring in real time (immediately), so that the position and size of the region A can be changed while the practitioner and the patient interact. However, it is possible to measure colors for many parts and ranges.

  The color measurement process S13 is a process for obtaining a measurement value by directly measuring the patient's teeth in the region A determined in the process S12. In the color measurement process S13, the image obtained by the image pickup means 11 is decomposed into the RGB color space and / or HSV color space for each pixel in real time (immediately), and to what extent of all gradations for each of RGB and / or HSV Is converted into a numerical value and transmitted to the computing means 10 as an electrical signal. Then, the calculation means 10 performs calculation based on the program, and the color (brightness, saturation, hue) is quantitatively specified for each pixel from the signal obtained from the image pickup means 11 to obtain a measurement value. However, in the subsequent process, the average value of the values calculated from the colors of the pixels included in the region A is handled as the “measured value” of the region A, not for each pixel.

The comparison determination process S14 is a process of comparing the measurement value obtained in the color measurement process S13 with the reference value obtained in the process S11. That is, a plurality of reference values registered in step S11 that are slightly different in color are compared with the measured values obtained in step S13 one by one. If the measured value matches the reference value in step S14, Yes is selected and the process proceeds to the next step. On the other hand, if the measured value and the reference value do not match, No is selected, the reference value is changed to a different reference value among the plurality of reference values (step S141), and the color measurement is performed again in step S13. Comparison is performed in the comparison determination step S14.
At this time, assuming that the exact match between the reference value and the measured value is the condition of Yes, it is virtually impossible to set it to Yes. Therefore, a certain color difference is allowed, and the measured value for determining Yes is predetermined. It is preferable to give a width of.

  By such comparison determination process S14, the closest color sample is extracted from the existing shade guides.

In the result output process S15, the comparison result with the extracted color sample is displayed on the display means 15.

  In the continuous measurement determination process S16, it is determined whether to measure again by changing the position and size of the region A based on the result output in the process S15. If “Yes” is selected here, the process returns to step S12 again to change the setting of the area A and perform the processes in and after step S13. On the other hand, if No is selected here, the measurement ends.

  According to the tooth color measurement method S10, color measurement is performed by a real-time (immediate) image of the tooth imaged in the process S13, and an objective result that is not subjective can be obtained on the spot. Therefore, it is possible to determine the color of the dental prosthesis while the practitioner and the patient talk based on the result. If necessary, the re-measurement is less burdened on the patient, as shown in step S16, and can be easily performed as desired by the patient.

  In addition, a display device corresponding to the communication means 16, for example, another pair of tooth colorimetric devices 1 is connected via the Internet, and the colorimetric information is communicated and displayed in real time so that the patient and the dental The prosthesis creator can also know the color measurement status in real time.

1 Tooth color measuring device 10 Calculation means (color measurement calculation means)
11 Imaging means 12 Input means 13 Storage means 14 RAM
15 Display means 16 Communication means

Claims (4)

Using an apparatus including an imaging unit, a storage unit, and a calculation unit,
A plurality of color samples having different colors are photographed by the imaging unit, and the signal from the imaging unit is quantified by the calculation unit, and this is stored in the storage unit as a reference value for each of the plurality of color samples. ,
From the immediate image of the tooth to be measured, the color is quantitatively converted into numerical values by the calculation means, and this is used as a measurement value.
A tooth colorimetric method for comparing the reference value with the measured value and extracting a sample of the closest reference value. Imaging means having an element for converting the captured video into an electrical signal;
Quantify the color from a plurality of color samples with different colors taken by the imaging means and use these as reference values for each color sample, and quantitatively quantify the color from the immediate image of the tooth to be measured. Calculating means, and comparing the reference value and the measured value to extract a sample of the closest reference value;
Storage means for storing a calculation result by the calculation means;
A tooth colorimetric device comprising: display means for displaying at least a part of a result computed by the computing means.   The tooth colorimetric apparatus according to claim 2, wherein the imaging unit, the calculation unit, the storage unit, the display unit, and the communication unit are all housed in one housing. Acquiring a plurality of color samples having different colors by the imaging unit, quantifying the color by the calculation unit, and storing the swatches in the storage unit as respective reference values of the plurality of color samples;
A step of quantitatively quantifying the color from the immediate image of the tooth to be measured by the calculation means and setting it as a measurement value;
A tooth colorimetry program, comprising: causing the arithmetic means to compare the reference value and the measured value to extract a sample of the closest reference value.

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