METHOD AND APPARATUS FOR MEASURING AND DISPLAYING DENTAL PLAQUE, GINGIVA, AND ALVEOLAR BONE

• US 20150182120A1
• Filed: 07/12/2013
• Published: 07/02/2015
• Est. Priority Date: 07/19/2012
• Status: Active Grant

• Current Assignee: National Center For Geriatrics And Gerontology
• Original Assignee: National Center For Geriatrics And Gerontology
• Inventors: Sumi, Yasunori, Ozawa, Nobuyoshi, Gonda, Yohei
• Granted Patent: US 9,445,724 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2576/02 specially adapted for a particular organ or body part
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/0086 using infrared radiation
• CPC Class Codes: A61B 5/0088 for oral or dental tissue
• CPC Class Codes: A61B 5/4552 Evaluating soft tissue within the mouth, e.g. gums or tongue
• CPC Class Codes: A61C 19/04 Measuring instruments specially adapted for dentistry A61C5/44 takes precedence; testing vitality of teeth A61B5/0534; radiation diagnosis specially adapted for dentistry A61B6/51

Abstract

A method and an apparatus for measuring and displaying dental plaque are provided, and the method includes the steps of dividing near infrared light output from a light source into measurement light and reference light, applying the measurement light toward a tooth in an oral cavity and scanning the tooth with the measurement light, producing interference light from reflected light and back-scattered light from the tooth and the reference light, generating an optical coherence tomographic image based on a scattering intensity value of the interference light, extracting a dental plaque region having a specific scattering intensity value from the optical coherence tomographic image, and quantifying the dental plaque. A method and an apparatus for measuring and displaying gingiva and/or alveolar bone are further provided. A method and an apparatus for quantifying dental plaque, digitizing the dental plaque, and generating an image of the dental plaque are further provided.

Claims

1. A method for measuring and displaying dental plaque, comprising the steps of:

dividing near infrared light output from a light source into measurement light and reference light;

applying the measurement light toward a tooth in an oral cavity, and scanning the tooth with the measurement light;

producing interference light from reflected light and back-scattered light from the tooth and the reference light;

generating an optical coherence tomographic image based on a scattering intensity value of the interference light;

extracting a dental plaque region having a specific scattering intensity value from the optical coherence tomographic image;

quantifying the dental plaque; and

generating an image of the dental plaque.

2. The method according to claim 1,

wherein the optical coherence tomographic image is a two-dimensional optical coherence tomographic image that two-dimensionally displays the dental plaque region, an enamel region on which the dental plaque is attached, and a gingiva region distinguishably from one another.

3. The method according to claim 1,

wherein the optical coherence tomographic image is a three-dimensional optical coherence tomographic image that three-dimensionally displays, as a stereoscopic image, the dental plaque region, an enamel region on which the dental plaque is attached, and a gingiva region distinguishably from one another.

4. The method according to claim 1,

wherein the optical coherence tomographic image is a combination of a two-dimensional optical coherence tomographic image that two-dimensionally displays the dental plaque region, an enamel region on which the dental plaque is attached, and a gingiva region distinguishably from one another and a three-dimensional optical coherence tomographic image that three-dimensionally displays, as a stereoscopic image, the dental plaque region, an enamel region on which the dental plaque is attached, and a gingiva region distinguishably from one another.

5. The method according to claim 2,

wherein the step of quantifying the dental plaque includes a step of digitizing a thickness and/or a length of the dental plaque based on the dental plaque region extracted from the two-dimensional optical coherence tomographic image.

6. The method according to claim 3,

wherein the step of quantifying the dental plaque includes a step of digitizing a volume of the dental plaque based on the dental plaque region extracted from the three-dimensional optical coherence tomographic image.

7. The method according to claim 2,

wherein the step of quantifying the dental plaque includes a step of digitizing a cross-sectional area of the dental plaque based on the dental plaque region extracted from the two-dimensional optical coherence tomographic image or the three-dimensional optical coherence tomographic image.

8. The method according to claim 2,

wherein the step of quantifying the dental plaque includes a step of digitizing a surface area of the dental plaque based on the dental plaque region extracted from the three-dimensional optical coherence tomographic image.

9. The method according to claim 1, further comprising the steps of:

creating a database containing at least one quantified value selected from a thickness of the dental plaque, a length of the dental plaque, a volume of the dental plaque, a cross-sectional area of the dental plaque, and a surface area of the dental plaque obtained in the step of quantifying the dental plaque; and

displaying the quantified value in the time course in at least one form selected from an image, a table, and a graph.

10. The method according to claim 9, further comprising the step of calculating an amount of change in the time course in at least one quantified value selected from the thickness of the dental plaque, the length of the dental plaque, the volume of the dental plaque, the cross-sectional area of the dental plaque, and the surface area of the dental plaque, and displaying the calculated value in the time course in the form of a numerical value, a two-dimensional image, or a three-dimensional image.

12. Software that causes a computer to execute a method for measuring and displaying dental plaque, the method comprising the steps of:

generating an optical coherence tomographic image based on the scattering intensity value of the interference light obtained by the method according to claim 1;

extracting a dental plaque region based on the scattering intensity value of the interference light;

generating an image of the dental plaque region; and

providing at least one quantified value selected from a thickness of the dental plaque, a length of the dental plaque, a cross-sectional area of the dental plaque, a volume of the dental plaque, and a surface area of the dental plaque based on the extracted dental plaque region.

13. The software according to claim 12,

wherein before the step of extracting the dental plaque region, the method executed by the computer further comprises the step of morphologically identifying the dental plaque, gingiva, and enamel in the optical coherence tomographic image based on an anatomical fact.

14. The software according to claim 12,

wherein the method executed by the computer further comprises the steps of:

creating a database containing a value provided in the step of providing a quantified value; and

displaying the quantified value in the time course in at least one form selected from an image, a table, and a graph.

11. An apparatus for measuring and displaying dental plaque, the apparatus comprising:

a light source that outputs near infrared light;

a splitter that divides the near infrared light into measurement light and reference light;

a dental plaque measuring probe that applies the measurement light toward a tooth in an oral cavity, and that scans the tooth with the measurement light;

a light receiving element that receives interference light produced from reflected light and back-scattered light from the tooth and the reference light;

a computing section that converts a scattering intensity value of the interference light into a gray level value, and that generates an optical coherence tomographic image;

an extraction/measurement section that extracts a dental plaque region, and that quantifies the dental plaque; and

a display section that displays the optical coherence tomographic image and a result of the quantification.

15. A method for measuring and displaying gingiva and/or alveolar bone, the method comprising the steps of:

dividing near infrared light output from a light source into measurement light and reference light;

applying the measurement light toward a tooth and periodontal tissue in an oral cavity, and scanning the tooth and the periodontal tissue with the measurement light;

producing interference light from reflected light and back-scattered light from the tooth and the periodontal tissue and the reference light;

generating an optical coherence tomographic image based on a scattering intensity value of the interference light;

extracting a gingiva region and/or an alveolar bone region each having a specific scattering intensity value;

quantifying the gingiva and/or the alveolar bone; and

generating an image of the gingiva and/or the alveolar bone,

wherein the method further comprises the step of obtaining an amount of change in swelling of the gingiva and/or an amount of change in the alveolar bone by carrying out the step of quantifying gingiva and/or alveolar bone in the time course.

17. Software that causes a computer to execute a method for measuring and displaying gingiva and/or alveolar bone, the method comprising the steps of:

generating an optical coherence tomographic image based on the scattering intensity value of the interference light provided by the method according to claim 15;

extracting a gingiva region and/or an alveolar bone region based on the scattering intensity value of the interference light;

generating an image of the gingiva region and/or the alveolar bone region;

quantifying the gingiva and/or the alveolar bone based on the extracted gingiva region and/or alveolar bone region; and

measuring an amount of change in swelling of the gingiva and/or an amount of change in the alveolar bone by carrying out the step of quantifying gingiva and/or alveolar bone in the time course.

16. An apparatus for measuring and displaying gingiva and/or alveolar bone, the apparatus comprising:

a light source that outputs near infrared light;

a splitter that divides the near infrared light into measurement light and reference light;

a measuring probe that applies the measurement light toward a tooth and periodontal tissue in an oral cavity, and that scans the tooth and the periodontal tissue with the measurement light;

a light receiving element that receives interference light produced from reflected light and back-scattered light from the tooth and the periodontal tissue and the reference light;

a computing section that converts a scattering intensity value of the interference light into a gray level value, and that generates an optical coherence tomographic image;

an extraction/measurement section that extracts a gingiva region and/or an alveolar bone region, and that quantifies the gingiva and/or the alveolar bone; and

a display section that displays the optical coherence tomographic image and a result of the quantification.