JP2020093061A - Periodontal disease diagnosis support apparatus, and method and program for the same - Google Patents

Abstract

[Problem] In periodontal disease examination, it is possible to obtain quantified and numeric examination criteria that can objectively judge the degree of progression of periodontal disease, greatly improving testability and safety while making diagnosis. To provide a periodontal disease diagnosis support device and method that can significantly improve the objectivity of periodontal disease diagnosis. A periodontal disease diagnosis support device according to the present invention includes a tooth shape detection unit that detects the shape of a tooth including at least the position of the alveolar bone crest from a dental image taken by an imaging device; and an alveolar bone resorption degree calculation unit that calculates the alveolar bone resorption degree using information on the shape of the tooth including the alveolar bone apex. [Selection diagram] Figure 2

Description

The present invention relates to a periodontal disease diagnosis support device utilizing dental images, a method thereof, and a program, and in particular, a tooth that can be used for diagnosing periodontal disease by arithmetically processing detection data from a dental X-ray image. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a peripheral disease diagnosis support device, a method thereof, and a program.

Periodontal disease is a disease in which chronic gingivitis progresses and inflammation spreads to periodontal tissues other than the gingiva and is accompanied by progressive destruction of periodontal tissues. Clinically, chronic inflammation of the gingiva, hemorrhage from the periodontal pocket, alveolar bone retraction, etc. occur, and the swaying or movement of the tooth occurs due to the progress of destruction, and eventually the tooth spontaneously falls off or needs to be extracted. Is known to occur.

In the treatment of periodontal disease, it is necessary to first examine how advanced the present condition is, and then diagnose what kind of condition it leads to. Test items for periodontal disease are roughly classified into tests for bacterial infection and inflammation, tests for tissue destruction, tests for occlusion and risk factors, and the like. The present application is an invention relating to the technical concept of the probing pocket depth test and the alveolar bone resorption test using dental X-rays among the tests related to tissue destruction.

The probing pocket depth inspection method will be described below with respect to the progressing state of periodontal disease. FIG. 1 is a conceptual cross-sectional view schematically showing a lower jaw tooth in periodontal disease. As shown in FIG. 1, a tooth has a tooth root 4 supported by an alveolar bone 8 and gum (gum) 6, and a portion between the tooth root 4 and the gum 6 is called a periodontal pocket (gingival groove) 10. When suffering from periodontal disease, the gingiva becomes swollen red, the periodontal ligament is broken, blood and pus are discharged from the periodontal pocket, and the alveolar bone 8 begins to melt. The depth of the pocket from the gingival apex 7 to the lower end of the periodontal pocket 11 is about 0 to 1 mm in a healthy tooth, but in the case of a tooth suffering from periodontal disease, the depth of the pocket depends on the progress of the periodontal disease. It gets deeper with it.

In the probing pocket depth inspection method, a periodontal probe (inspection needle, more specifically, a graduated needle called a pocket probe) 15 is inserted into the periodontal pocket between the gingiva and the tooth root to the lower end of the periodontal pocket to detect the periodontal pocket. This is the most convenient method, as it measures the depth while searching for the condition of symptoms. Although it is measured at about 4 to 6 points on one tooth, it may cause bleeding, which causes pain to the patient and is troublesome. Further, as described later, there is a problem that it cannot be said to be sufficient as an objective index of periodontal disease. Judgment by the probing pocket depth inspection method is generally considered to be mild periodontitis if the periodontal pocket depth is 3 mm or less, moderate periodontitis at 4 to 6 mm, and severe periodontitis at 7 mm or more. ..

Next, an alveolar bone resorption test method will be described. The alveolar bone resorption is the alveolar bone distance absorbed (the length from the cement-enamel boundary 3 to the alveolar crest 9 (E+D)) with respect to the root length (the length from the cement-enamel boundary 3 to the root apex 5 (E+D)). )). In periodontal disease, as the alveolar bone begins to melt as described above, the alveolar bone crest gradually decreases, the periodontal pocket depth increases, and the absorbed alveolar bone distance (the length from the cement-enamel boundary to the alveolar bone crest) E also increases. The ratio of the absorbed alveolar bone distance E to the root length (D+E) is defined as the alveolar bone resorption degree.

Judgment by the alveolar bone resorption test method is generally mild periodontitis when the alveolar bone resorption is less than 30%, moderate periodontitis when the alveolar bone resorption is less than 30% and less than 50%, and 50% or more (alveolar bone resorption If the degree is more than 1/2 of the root length), it is considered to be severe periodontitis. However, since the alveolar bone resorption degree is read and measured from a dental radiographed image using dental X-rays, there is a drawback that it is greatly influenced by the doctor's skill level and judgment criteria.

Conventionally, various proposals have been made by the following prior arts regarding periodontal disease inspection methods including the above-mentioned probing pocket depth inspection method and alveolar bone resorption degree inspection method.

For example, in Patent Document 1, a technical idea of processing a tomographic image around a tooth portion obtained by using an OCT apparatus to create a two-dimensional image and measuring a height of an alveolar bone and a contour portion of a periodontal pocket is described. It is disclosed. However, this technique using a laser light source has a problem that the depth of the periodontal pocket hidden in the gingiva is an estimated value and cannot be accurately measured. In addition, there is a drawback in that the measurement method is very difficult to adjust optically.

Further, Patent Document 2 discloses a technical idea of measuring the amount of substance called autoinducer-2 collected from dental plaque in the oral cavity of a patient and diagnosing the degree of periodontal disease that is correlated with the amount of autoinducer. Has been done. However, even in this case, there are drawbacks that effective results cannot be obtained in determining the results depending on the plaque sampling position and whether the degree of periodontal disease progression is the whole tooth or local tooth. ing.

JP, 2009-131313, A JP, 2010-256190, A JP, 2010-218562, A

In the diagnosis of periodontal disease, as described above, the probing pocket depth method is painful because a periodontal probe having a sharp tip is inserted into all gums and the depth thereof is visually measured. There are many bleeding, and the patient's pain and mental burden are large. In order to diagnose the degree of progression of periodontal disease of the entire gum, it is necessary to diagnose the probing pocket depth of the whole tooth, which is troublesome and not easy.

The probing pocket depth method is not only painful, it not only damages the teeth and periodontal tissues and exacerbates the disease, but also has the disadvantage that the periodontal disease-causing microorganisms are infected in different periodontal pockets. is there. There is also a problem that it cannot be said to be sufficient as an objective index of periodontal disease. That is, even if the depth of the periodontal pocket is the same, the volume of the tooth below the periodontal pocket differs from tooth to tooth and from person to person.Therefore, the force that supports the tooth is determined only by the depth of the periodontal pocket. You cannot do it.

As described above, the periodontal disease is diagnosed by measuring the alveolar bone resorption, and as described above, the absorbed alveolar bone distance (cement-enamel boundary 3 relative to the root length (the distance between the cement-enamel boundary 3 and the apex 5 (E+D))). To the alveolar bone crest 9 (E)), which is the ratio of alveolar bone resorption. However, alveolar bone resorption is actually very difficult to measure. Since the root apex cannot be visually observed, a dental X-ray image is taken. The root apex can be confirmed from the dental X-ray image, but this time the cement-enamel boundary is unknown on the image and its position cannot be determined. Since the cement-enamel boundary is to be visually confirmed, it is extremely difficult to understand because it is necessary to match the image data with the visual data.

The alveolar bone resorption rate is indicated by the ratio to the root length, but there is no strict definition on the image of the measurement of the ratio to the root length, and the dentist can visually observe "no alveolar bone resorption" and "mild periodontium". The reality is that "flame", "moderate periodontitis" and "severe periodontitis" are identified. For this reason, when a diagnosis is made in units of one tooth, if mild, moderate, and severe coexist, it is possible to judge whether to describe the disease name based on the most severe tooth or the disease name with the largest number of affected teeth. It can be different.

As described above, the diagnosis of periodontal disease relies on the skill of a doctor, and it has been difficult to obtain quantitative and objective alveolar bone resorption data and its diagnosis. In the conventional examination/diagnosis of periodontal disease, there are various problems such as differences in examination judgment depending on the examiner, and certain objective data cannot be obtained.A diagnostic method that can objectively judge the degree of progression of periodontal disease There has been a demand for a support device that obtains quantified and quantified examination criteria.

The present invention is intended to solve the above-mentioned problems in the prior art, and it is possible to improve the testability and safety in the examination of periodontal disease, and at the same time, to improve the objectivity of measurement data. It is an object of the present invention to provide a disease diagnosis support device, a method thereof, and a program.

In order to solve such a problem, the periodontal disease diagnosis support device according to the present invention,
From a dental image taken by the imaging device, a tooth shape detection unit that detects at least the shape of the tooth including the position of the alveolar bone crest,
An alveolar bone resorption rate calculation unit that calculates the alveolar bone resorption rate using information on the shape of the tooth portion including the detected alveolar bone top portion.

That is, the periodontal disease diagnosis support apparatus according to the present invention detects the shape of a tooth portion such as the alveolar crest by comparing a dental X-ray image of a periodontal disease patient with a typical periodontal disease X-ray image. Then, the required dimension is measured from the shape information, and the alveolar bone resorption degree is calculated. Since there is no intervention of human visual judgment, it is possible to calculate the alveolar bone resorption degree objectively and without variation. In addition, since objective alveolar bone resorption data can be presented, there is no difference in the diagnostic result of the inspector, and it is possible to assist in realizing an accurate examination judgment.

The periodontal disease diagnosis support device according to the present invention further detects the position of the tooth tip (root apex) and the position of the crown tip, and in the alveolar bone resorption calculation unit, information on the shape of the tooth. Alternatively, the alveolar bone resorption degree can be calculated using information on the position of the alveolar bone crest, the position of the dental bone tip (root apex), and the position of the crown tip.

The alveolar bone resorption is defined as described above with respect to the absorbed alveolar bone distance (distance from cement-enamel boundary 3 to alveolar crest 9) with respect to root length (distance from cement-enamel boundary 3 to apex 5 (E+D)). (E)). However, since the cement-enamel boundary is identified on the same tooth surface, it is difficult to determine its position from the dental X-ray image. On the other hand, in the periodontal disease diagnosis support apparatus according to the present invention, the alveolar bone resorption degree is tentatively defined as the ratio of the length from the root apex to the alveolar crest to the tooth length (D/C in FIG. 1). To do. This tentatively defined value of alveolar bone resorption is correlated with the value of alveolar bone resorption (E/(D+E) in FIG. 1) defined in the related art, and thus can be used as a substitute.

The tentative definition of alveolar bone resorption is because the apex (dental tip), occlusal part (crown tip), and alveolar bone crest can be easily identified from the dental X-ray image, so that the measured values have no error and The calculated value of bone resorption becomes an objective value without variation. The periodontal disease diagnosis support device according to the present invention detects the tooth length from the position of the root apex and the position of the crown tip, and detects the length from the positions of the alveolar crest and the root apex, and alveolar bone The absorptivity calculation unit calculates alveolar bone resorption by a tentative definition.

Therefore, the calculated value of the alveolar bone resorption degree by the periodontal disease diagnosis support device according to the present invention accurately represents the concept equivalent to the original alveolar bone resorption degree and is presented as a value without variation. As a result, there is no difference in the diagnostic result of the inspector, and it is possible to support the realization of accurate medical examination judgment.

The alveolar bone resorption degree by the periodontal disease diagnosis support device according to the present invention is the average of the positions of the alveolar bone crest, the position of the dental bone tip, and the position of the crown tip, for a plurality of adjacent tooth portions. It is also possible to adopt a configuration in which

Since there are variations in the individual positions of a plurality of adjacent tooth portions, by calculating the alveolar bone resorption from a value obtained by averaging each position, in the present invention, the averaged alveolar tooth for each adjacent tooth portion. Calculate and present the bone resorption rate. This allows the inspector to diagnose the degree of progression of periodontal disease for each group of adjacent tooth portions. Similarly, since the number of measurement positions and the number of measurements can be averaged and calculated, a more reliable value of alveolar bone resorption can be presented.

The periodontal disease diagnosis support device according to the present invention can also be configured to have a display unit that displays at least one of a dental image, information on the shape of the tooth portion, and a calculation result of the alveolar bone resorption degree.

That is, since the photographed image of the tooth portion is displayed on a display or the like, the examiner can visually recognize the shape of the tooth portion, for example, the position/shape of the crown tip portion, the root apex portion, and the alveolar bone crest portion. In addition, since the calculated value of the calculated alveolar bone resorption degree is displayed in the same manner, the examiner can make a medical examination judgment while considering the value of the alveolar bone resorption degree while visually recognizing the shape of each tooth.

The periodontal disease diagnosis support device according to the present invention, as the information of the shape of the tooth portion, at least one piece of information of the position of the alveolar crest, the position of the tooth tip, and the position of the crown tip is It is also possible to adopt a configuration in which a plurality of matching tooth portions are connected and displayed on the display unit. Further, the connection may be approximated by a curve and displayed.

In the present invention, the position of the alveolar crest of the tooth shape displayed on the display, the position of the tooth tip, and the position of the crown tip are connected and displayed as a line. Further, the connection line is displayed as a smooth approximated curve. Therefore, the inspector can diagnose the periodontal disease and judge the degree of progress of the whole tooth part or a part of the tooth part group. Similarly, the examiner can examine the periodontal disease and consider the degree of progress while considering the calculated value of the alveolar bone resorption degree displayed in the whole tooth part or a part of the tooth part group. In particular, being able to make a diagnosis while visually recognizing the connection line of each tooth portion displayed superimposed on the tooth image is very effective for an inspector who aims at an accurate and objective examination judgment.

The dental imaged image related to the periodontal disease diagnosis support device according to the present invention is not limited to the X-ray imaged image, and may be a CT imaged image. In addition, since the tooth shape detection unit that detects the shape of the tooth including the position of the alveolar bone crest has a plurality of typical periodontal disease tooth imaging data, it is possible to determine the tooth shape from the dental image to be examined. If it cannot be detected, the typical imaging data of periodontal diseased tooth portion is compared, the most approximated imaging data of periodontal diseased tooth portion is selected, and the shape of the tooth portion is detected from the data.

As described above, in the diagnosis of periodontal disease, quantitative and objective acquisition of alveolar bone resorption data and its diagnosis can be performed without relying only on the skill of a doctor. There is no variation in the examination judgment by the examiner, and it becomes possible to make accurate examination judgment of periodontal disease based on certain objective data and tooth image.

ADVANTAGE OF THE INVENTION According to this invention, the objectivity of a measurement data is also improved remarkably, improving testability and safety in the periodontal disease medical examination. In place of the conventional inspection method, it becomes possible to perform periodontal disease diagnosis that significantly improves reliability, safety, and economic efficiency.

It is a cross-sectional conceptual diagram which showed typically the mandibular tooth in periodontal disease. It is a functional block diagram which comprises the periodontal disease diagnosis support apparatus, method, and program which concern on one Embodiment of this invention. 3 is a timing flowchart for explaining the operation of the periodontal disease diagnosis support device/method/program according to the embodiment of the present invention. It is a dental X-ray image of typical periodontal disease (individual tooth portion of the lower jaw). It is the figure which showed the concept of the averaging method of the alveolar bone resorption measurement value of the periodontal disease diagnosis support apparatus which concerns on one Embodiment of this invention. It is the figure which showed the dental panoramic X-ray image and tooth line which were displayed on the periodontal disease diagnosis support apparatus which concerns on one Embodiment of this invention. It is the figure which showed the dental X-ray image displayed on the periodontal disease diagnosis support apparatus which concerns on one Embodiment of this invention. It is the figure which showed the dental panoramic X-ray image and alveolar bone top part line displayed on the periodontal disease diagnosis support apparatus which concerns on one Embodiment of this invention.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the following, the range necessary for the explanation to achieve the object of the present invention is schematically shown, and the range necessary for the explanation of the relevant part of the present invention will be mainly explained, and about the place where the explanation is omitted, A known technique is used.

FIG. 2 is a functional block diagram of an alveolar bone resorption measurement support device according to an embodiment of the present invention. As shown in FIG. 1, the apparatus 1 is roughly configured to include at least an X-ray imaged image data acquisition unit 100, an X-ray image data storage server 101, a control device 102, and a display device 103. The control device 102 reads and analyzes the data transmitted from the X-ray imaged image data acquisition unit, the image analysis unit 104 that extracts the approximated image data from the X-ray image data storage server 101, the imaged data and the approximated data. A collation measurement unit 106 that collates image data and measures each part, an arithmetic analysis processing unit 107 that arithmetically processes the measurement data, a storage unit 108 that stores each processed data, and a display processing unit 109 that transmits display data to the display device 103. Is configured.

The X-ray picked-up image data acquisition unit 100 is connected to the dental X-ray image pickup apparatus or is in a state capable of transmitting and receiving information data. Alternatively, the X-ray imaged image data acquisition unit 100 may be configured integrally with the dental X-ray imaging apparatus 110.

The X-ray image data storage server 101 stores various dental X-ray images of periodontal disease as well as typical dental X-ray images of periodontal disease. The display device 103 displays the X-ray captured image data processed by the display processing unit 109 of the control device 102 and instructed to be displayed and various calculation analysis processing data, and displays information useful for a doctor's treatment judgment.

Next, the operation of the present apparatus configured as described above will be described. FIG. 3 is a timing flowchart for explaining the operation of the alveolar bone resorption measurement support device according to the embodiment of the present invention.

For example, when a dentist takes a dental X-ray image of a periodontal patient, the X-ray imaged image data is transferred to the X-ray imaged image data acquisition unit 100 by the X-ray image pickup device 110 (step H101). Hereinafter, the X-ray imaged image data will be referred to as “imaging data”. The imaging data may be imaging data by the 10 dental X-ray photography method or 14 dental X-ray photography method, or may be individual tooth imaging data.

The approximate data extraction unit 105 in the control device 102 analyzes the imaged data and extracts dental X-ray image data that is the most approximate image from the X-ray image data storage server (step H102). Hereinafter, the extracted dental X-ray image data will be referred to as “image data”. The approximate data extraction unit sends the image pickup data and the image data to the matching measurement unit 106. The collation measurement unit 106 collates the imaged data with the image data, and measures the data of the dental part necessary for the inspection and diagnosis of periodontal disease. Here, the measurement means, for example, specifying the crown position or the root apex position from the imaging data and measuring the tooth length. Further, collation and measurement, for example, when the position of the alveolar bone crest in the imaging data is unclear, collation is performed so as to superimpose image data that is approximate data, and the position of the alveolar bone crest is calculated from the superimposed image data. It refers to specifying and substituting the distance from the root apex position of the imaging data to the alveolar crest position. That is, for the data of the dental part that is difficult to measure from the imaged data, the position is read from the image data that is approximate data, and the image data and the approximated image data are superimposed to measure the length and the like (step H103).

The calculation analysis processing unit 107 performs calculation processing to describe the measured dental part data later according to a prescribed program (step H104). As will be described later, when calculating the alveolar bone resorption in periodontal disease, for example, the calculation analysis processing unit 107 measures the measurement data of the distance from the root apex to the alveolar bone crest, which is the measurement data from the matching measurement unit, and the tooth length. After obtaining the measurement data and calculating processing according to the defined formula, the alveolar bone resorption degree is calculated. In addition, in order to output information necessary for dental diagnosis, the calculation analysis processing unit 107 also has a function of processing various calculation programs that calculate the defined formula. For example, calculation processing of the area, volume, etc. of the diseased part is also included.

The display device 103 has a display function of displaying information for dental examination diagnosis and supporting a doctor's diagnosis. The display device 103 displays the dental image data of the patient, for example, an X-ray image of which is taken in accordance with an instruction (step H105) from the display processing unit 109 in the control device 102. Then, the information necessary for the dental diagnosis calculated by the calculation analysis processing 107 is also displayed. The calculation analysis data can be superimposed on the image data and displayed (step H106). For example, a curve connecting the occlusal positions of the teeth, a curve connecting the alveolar crests, a curve connecting the apexes, and the like can be superimposed and displayed on the dental image. Further, the type and display method of the display data are displayed according to the instruction of the display processing unit 109 such as numerical value display, list display, three-dimensional image display, virtual cross-section display, back-side display (step H106). In addition, the printout to the paper including the specific recording paper and the chart paper is also executed (step H107).

The in-apparatus information is recorded and stored in the storage unit 108, and can be sequentially extracted and utilized (step H108).

Next, a specific inspection method for measuring alveolar bone resorption in the periodontal disease periodontal disease diagnosis using the periodontal disease diagnostic support device according to the present invention, and the operation of the periodontal disease diagnostic support device will be described.

At the time of the examination, a dental X-ray image of the subject is taken, and the image pickup data is transmitted to the X-ray image pickup image data acquisition unit 100 of the periodontal disease diagnosis support device. The type of X-ray imaged image used in the periodontal disease diagnosis support device 1 according to the present invention is not limited, and a dental X-ray photo 10-image method image, a dental X-ray 14-image method image, a dental panorama. Any image such as an X-ray photograph image may be used. It may also be a CT CT image. In the following specific description and drawings, an image using the 10-dental X-ray photography method will be described as an example. These dental image capturing devices may be devices built in the periodontal disease diagnosis support device according to the present invention, or may be co-located devices capable of transmitting and receiving data.

The control device 102 of the periodontal disease diagnosis support device 1 according to the present invention analyzes the acquired imaging data and reads all the information and numerical values that can be detected in the imaging information. For example, the detectable information necessary for calculating the alveolar bone resorption degree such as the tooth length C from the crown tip to the root apex and the absorbed alveolar bone distance D from the alveolar crest to the root apex is read.

If some of the imaging data information is unclear and cannot be detected, such as the position of the alveolar bone crest, the most approximate image data among the typical periodontal disease image data stored in the X-ray image data storage server 101 is approximate. It is selected and extracted by the data extraction unit 105. For example, the case where the position of the alveolar crest is unclear and cannot be detected will be described below as an example.

FIG. 4 is an example of typical periodontal disease image data (individual tooth portions of the lower jaw) stored in the X-ray image data storage server 101. The Normal image in FIG. 4 is normal, the Mild image is an early periodontal disease, the Moderate image is a typical periodontal disease, and the Severe image is an image representing severe periodontal disease. The approximate data extraction unit 105 extracts, from these image data, the one that is the closest to the imaged data while sequentially collating it. In this extraction operation, a known algorithm in the technical idea of the fingerprint authentication system disclosed in Patent Document 3 can be used. As shown in one image data in FIG. 4, the black triangular portions located above the left and right tooth roots 4 and the alveolar bone 8 located between them are the features of the periodontal disease dental image, and the black triangular portions The lower end is the alveolar crest. For example, by designating the lower end of the black triangular portion as the alveolar crest, the position of the alveolar crest can be identified, and the length D from that point to the root apex can be measured.

In this way, the collation measuring unit 106 superimposes the approximate image data extracted from the typical periodontal disease image data and the imaged data of the subject, and collates them to identify the position of the alveolar bone crest that was unclear. It has a function to calculate the length to the root apex. As described above, not only the alveolar bone crest, but all the information that can be detected by collating the imaging data and the approximate image data can be detected and calculated.

The calculation analysis processing unit 107 calculates and calculates the alveolar bone resorption degree based on the detected data according to, for example, a defined formula (definition formula). As shown in FIG. 1, the definition of the alveolar bone resorption is originally based on the absorbed alveolar bone distance (from the cement-enamel boundary 3 to the root length (the distance from the cement-enamel boundary 3 to the root apex 5 (E+D))). It is the ratio of the distance (E) to the alveolar bone crest 9. That is, E/(E+D). However, the position of the cement-enamel boundary is difficult to judge because the position is unclear from the dental X-ray image because it is the surface of the same tooth bone, and therefore the periodontal disease diagnosis support apparatus according to the present invention uses the alveolar bone. The absorbency is tentatively defined as the ratio of the length from the root apex to the alveolar crest to the tooth length (D/C in FIG. 1).

A tentative definition of alveolar bone resorption is shown.
Alveolar bone resorption=1/n Σ (length from root apex to alveolar crest/tooth length) [%]
= 1/n Σ (D/C) [%]
Tooth length: Length C from root apex to crown tip
n: Number of measurement points

According to this definition, it is possible to make a trial calculation based on the positional information of the root apex (the tip of the bone), the occlusal portion (the tip of the crown), and the alveolar crest that can be clearly detected from the dental X-ray imaging. The error of the value of the alveolar bone resorption is eliminated, and the fluctuation of the calculated value can be prevented, which serves the purpose of objective quantification. This tentatively defined value of alveolar bone resorption is correlated with the value of alveolar bone resorption (E/(D+E) in FIG. 1) defined in the related art, and thus can be used as a substitute.

That is, the periodontal disease diagnosis support device according to the present invention detects the tooth length from the position of the root apex and the position of the crown tip, and detects the length from the positions of the alveolar crest and the root apex, the alveolar The bone resorption rate calculation unit is characterized in that it calculates the alveolar bone resorption rate by provisional definition. However, the definition of alveolar bone resorption is not limited to this tentative definition, and it goes without saying that the defining formula can be changed. Further, it is also a part of the technical idea of the present application to define and formulate parameters for other diagnosis determination regarding periodontal disease from other information detected from the imaged data and the image data, formalize and set them.

In this provisional definition, the alveolar bone resorption is quantified as an average ratio of the number of measurement points n to one site. The existing definition is that “diagnosis for one tooth” and “integration of evaluation for one tooth” are performed to perform “diagnosis at an individual level”. As in the present application, one tooth site or one tooth group On the other hand, the idea of measuring the alveolar bone resorption rate at multiple points and averaging it is unprecedented.

FIG. 5: is the figure which showed the concept of the averaging method of the alveolar bone resorption measurement value of the periodontal disease diagnosis support apparatus which concerns on one Embodiment of this invention. The broken line alveolar in this figure is the length D from the root apex to the alveolar crest in FIG. The straight line teeth is the tooth length C in FIG. FIG. 5 shows the operation of averaging the alveolar bone resorption calculation values at the number of measurement points n. For example, if three positions of tooth root apex (dental tip), occlusal part (crown tip), and alveolar crest are detected in one tooth and three types of alveolar bone resorption are calculated, n becomes 3. The three types of alveolar bone resorption are divided by 3 and averaged. As a result, the degree of alveolar bone resorption in the above-mentioned one tooth portion is shown as an average value with no variations, which is more effective information for the examiner to diagnose the degree of periodontal disease progression. The diagnosis in one tooth will be made accurately without being confused by the partial narrow local assessment.

Similarly, a case of examining periodontal disease in a group of 6 lower anterior teeth in the method of 10 dental X-ray photographs will be described. The position information of the root apex (the tip of the bone), the occlusal part (the tip of the crown), and the alveolar crest of the six teeth is detected, for example, at three locations in each of three locations and a total of 18 alveolar bone resorptions are calculated. In that case, n becomes 18, and the alveolar bone resorption is divided by 18 and averaged. As a result, the alveolar bone resorption degree in the lower anterior tooth portion is shown as an average value without variation, and more effective information is available for the inspector to diagnose the degree of periodontal disease progression of the lower six anterior teeth as a whole. Becomes The examination method is suitable for the characteristic of periodontal disease that the condition is likely to progress in units of adjacent tooth groups.

Similarly, it can be performed for the entire tooth. In addition, the average value by n is calculated as a weighted average value of the alveolar bone resorption degree in the adjacent tooth group including the tooth by increasing the number of times of measurement n of only one tooth part where periodontal disease has significantly progressed, for example. It is also possible to do so. In this case, the information is effective for the medical examination and judgment of the entire group tooth part including the tooth part in which the condition has advanced extremely. Calculation processing instructions such as designation of the measurement site, designation of the number of measurements, change of official calculation, execution of weighted average processing, etc. are performed by the examiner by operating and inputting the operation unit of the periodontal disease diagnosis support device. It is sent to the section 107.

Next, the display device 103 will be described. FIG. 6 is a diagram showing a dental panoramic X-ray image and a tooth line displayed on the periodontal disease diagnosis support apparatus according to the embodiment of the present invention. The Root apex line shown in the figure shows the root apex line 14 (FIG. 1) in which the root apexes are smoothly connected. The Alveolar line shows the alveolar crest line 13 (FIG. 1) in which the alveolar crest is smoothly connected. Occlusion line indicates an occlusal line 12 (FIG. 1) in which the upper ends of the occlusal portions of the teeth are smoothly connected.

The display device 103 displays the dental imaging data as shown in FIG. 6, and the position data and the like detected by the collation measurement unit 106 is subjected to, for example, connection line processing by the display processing unit 109, and is superimposed on the dental imaging image. To display. This connection line formation processing is, for example, in the case of a crown line, the individual positions of the crowns of individual teeth are connected, and the line is made into a smooth curve and approximate curve processing is performed to superimpose it on the image. Means to display. This allows the examiner to grasp the level of the position of the alveolar crest with respect to the tooth length through the entire tooth image, which is very useful for the diagnosis of periodontal disease. It is possible to display the alveolar bone resorption calculated by the periodontal disease diagnosis support device as a line and display the value of the alveolar bone resorption as a numerical value. The line smoothly connecting the alveolar bone resorption degree is similar to the alveolar bone crest line, but by taking a method such as the weighted average as described above, useful diagnostic information different from the alveolar bone crest line can be provided.

If we consider horizontal bone resorption when the disease state progresses uniformly on average over the entire tooth area, a technique for quantifying alveolar bone resorption based on such three smooth lines. Is an effective indication to the inspector of the condition mainly due to horizontal bone resorption. Regarding the process of drawing three lines and the process of quantifying the alveolar bone resorption degree based on the three lines, it is possible to perform the connection line processing as described above and similarly display it on the dental image. A person can easily evaluate a medical condition by visually confirming the alveolar bone resorption data independent of subjectivity.

Contrary to the above, when the apical root, alveolar crest and occlusal part are superimposed on the dental imaging image for each tooth measurement point and displayed as a dot (plot display), periodontal diagnosis for each tooth is performed. It is effective for diagnosing periodontal disease in adjacent tooth groups.

FIG. 7 is a diagram showing a dental X-ray image displayed on the periodontal disease diagnosis support device according to the embodiment of the present invention. This figure is an X-ray image of the upper left molar region of the upper jaw. As shown in the figure, among the seven adjacent tooth portions, there are tooth portions in which periodontal disease has significantly progressed and bone resorption has occurred. If the condition that progresses to a part of the teeth in the whole tooth is regarded as "vertical bone resorption", simple connecting line display or dot display (plot display) on the alveolar bone crest is shown in this way. Will be valid for diagnosis.

Based on this image information, the examiner can take various approaches for diagnosis, such as increasing the number of measurement points in the part where the periodontal disease progression is remarkable, or adding weighted average processing to the calculation formula of alveolar bone resorption. It will be possible to try. Calculating the difference between the maximum value and the minimum value, or calculating the amount of change in the alveolar bone resorption degree in a piecewise manner is effective information for evaluating the vertical resorption degree.

The connection lines of the root apex, alveolar crest, occlusal part, etc. are not limited to being displayed as smoothly connected lines, and can be displayed as a smoother approximation curve, or the plot points can be simply connected. Displaying is also performed by the display processing unit 109. For example, data such as impacted wisdom teeth (wisdom teeth), which hinders the creation of smooth connection of part lines such as root apex, alveolar crest, occlusal part, etc., can be ignored for display processing. This is because the shape and position of the embedded wisdom tooth are clearly different from the shapes and positions of the other teeth, and thus a smooth connection process cannot provide a preferable line for accurate diagnosis.

FIG. 8 is a diagram showing a dental panoramic X-ray image and an alveolar bone crest line displayed on the periodontal disease diagnosis support apparatus according to the embodiment of the present invention. As shown in the figure, for example, an alveolar bone crest line in which alveolar bone crests are smoothly connected is changed to a line calculated and processed according to the examiner's needs and displayed. It is possible to perform the processing that omits the above-mentioned impacted wisdom teeth and the curve processing that uses a specific template. For example, if the detection part information of the aged dental image data of the same subject is superimposed and displayed in a line so that the aged change can be seen, it is possible to clearly visually diagnose the aged progression of periodontal disease of the subject. It will be possible. As shown in FIG. 8, as for the display method of the tooth line, the examiner may select the display method most suitable for the diagnosis.

As described above, the periodontal disease diagnosis support apparatus according to the embodiment of the present invention, and the dental image and the specific site information using the method/program thereof, data such as alveolar bone resorption information and the like are displayed and displayed. By converting the method as necessary as described above, the inspector can obtain visually recognizable information that is very meaningful for the diagnosis of tooth disease such as periodontal disease. The information for these diagnoses is highly reliable because it is read from dental imaging data, and it is extremely valuable information for the purpose of medical examination judgment as objective data that does not include human subjectivity.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be carried out without departing from the gist of the present invention. For example, it is possible to use a dental image as CT (Computed Tomography) image data.

Up to the above, the dental imaged image is mainly described for the dental X-ray imaged data, but in the case of CT image data, the above-mentioned tooth detection lines and alveolar bone resorption display are superimposed and displayed. In addition, the information can be displayed from various angles or converted into a tomographic plane and displayed. Furthermore, it is possible to utilize the same mechanism for the inspection and diagnosis of tooth diseases not limited to periodontal disease. These are all part of this technical idea.

Further, in the above, the embodiment in which the technical idea of the present invention is realized as a periodontal disease diagnosis support device has been described, but it is also possible to realize all or part of each function as an algorithmized computer program, or as a method. It can be realized.

As described above, according to the invention of the present application, periodontal disease can be diagnosed by obtaining quantitative and objective alveolar bone resorption data, which does not rely only on the skill of a doctor. Accurate diagnosis of periodontal disease can be made based on objective data and tooth image.

INDUSTRIAL APPLICABILITY The present invention dramatically improves the objectivity and reliability of measurement data while significantly improving the testability and safety in periodontal disease examination. Therefore, the present invention is not limited to individual periodontal disease diagnosis support by a dentist, and brings advantages to all industries related to dental image capturing equipment, information processing equipment, and display devices and related industries. The industrial utility value and availability are extremely large.

1 Periodontal disease diagnosis support device 2 Crown 3 Cement-enamel boundary 4 Root 5 Root apex 6 Gingiva (gingiva)
7 Gingival Crest 8 Alveolar Bone 9 Alveolar Crest 10 Periodontal Pocket 11 Periodontal Pocket Lower End 12 Occlusion Line 13 Alveolar Crest Line 14 Apex Line 15 Periodontal Probe A Probing Pocket Depth (PD)
B Attachment level C Tooth length D Length from root apex to alveolar bone crest E Absorbed alveolar bone distance (length from cement-enamel boundary to alveolar crest)
D+E root length

Claims (15)

A storage device in which a typical periodontal disease image is stored,
From the dental image, which is image data extracted from the storage device as image data captured by an image capturing device that captures a dental image or data that is similar to the image data, at least the position of the alveolar bone crest and the tooth tip. A tooth part shape detection unit that detects the position and the shape of the tooth part including the position of the crown tip part at a plurality of positions for one tooth part or one tooth group,
Position of the alveolar crest as the information of the shape of the tooth portion detected at a plurality of positions for the one tooth site or one tooth group, the position of the tooth bone tip, and the position of the crown tip An alveolar bone resorption rate calculation unit for calculating alveolar bone resorption rate for a plurality of locations using information, and obtaining a quantified alveolar bone resorption rate by averaging the calculated alveolar bone resorption rates for a plurality of locations. Periodontal disease diagnosis support device having a. The tooth according to claim 1, wherein each of the position of the alveolar crest, the position of the tooth tip, and the position of the crown tip is averaged for a plurality of adjacent tooth portions. Periodontal diagnosis support device. The periodontal disease diagnosis according to claim 1 or 2, further comprising a display unit that displays at least one of the dental image, the information on the shape of the tooth portion, and the quantified alveolar bone resorption degree. Support device. As information on the shape of the tooth portion, the position of the alveolar bone crest portion, the position of the tooth bone tip portion, the position of the crown tip portion, any one or more information, a plurality of adjacent The periodontal disease diagnosis support device according to claim 3, wherein the tooth portions are connected and displayed on the display unit. The periodontal disease diagnosis support device according to claim 4, wherein the connection is approximated by a curve and displayed. Computer,
At least an alveolar bone from a dental image, which is image data captured by an imaging device that captures a dental image or image data extracted as data approximate to the imaging data from a storage device in which a typical periodontal disease image is stored A tooth portion shape detection unit that detects the shape of the tooth portion including the position of the top portion and the position of the dental bone tip portion and the position of the crown tip portion in a plurality of positions for one tooth portion or one tooth group,
Position of the alveolar crest as the information of the shape of the tooth portion detected at a plurality of positions for the one tooth site or one tooth group, the position of the tooth bone tip, and the position of the crown tip An alveolar bone resorption rate calculation unit for calculating alveolar bone resorption rate for a plurality of locations using information, and obtaining a quantified alveolar bone resorption rate by averaging the calculated alveolar bone resorption rates for a plurality of locations. A periodontal disease diagnosis support program, which is characterized by functioning as described above. The tooth according to claim 6, wherein the position of the alveolar bone crest, the position of the dental bone tip, and the position of the crown tip are averaged for a plurality of adjacent tooth portions. Periodontal diagnosis support program. The periodontal disease diagnosis according to claim 6 or 7, further comprising a display unit that displays at least one of the dental image, the information on the shape of the tooth portion, and the quantified alveolar bone resorption degree. Support program. As information on the shape of the tooth portion, the position of the alveolar bone crest portion, the position of the tooth bone tip portion, the position of the crown tip portion, any one or more information, a plurality of adjacent The periodontal disease diagnosis support program according to claim 8, wherein the tooth portion is connected and displayed on the display unit. The periodontal disease diagnosis support program according to claim 9, wherein the connection is approximated by a curve and displayed. At least an alveolar bone from a dental image, which is image data captured by an imaging device that captures a dental image or image data extracted as data approximate to the imaging data from a storage device in which a typical periodontal disease image is stored A first step of detecting a plurality of positions of a tooth portion including a position of a top portion, a position of a tooth tip portion, and a position of a crown tip portion with respect to one tooth portion or one tooth group;
The position of the alveolar crest as the information of the shape of the tooth portion detected at a plurality of positions for the one tooth site or one tooth group, the position of the dental bone tip, and the position of the crown tip. A second step of calculating alveolar bone resorption for a plurality of locations using information, and averaging the calculated alveolar bone resorption for a plurality of locations to obtain a quantified alveolar bone resorption. Periodontal disease diagnosis support method. The tooth according to claim 11, wherein the position of the alveolar bone crest, the position of the dental bone tip, and the position of the crown tip are averaged for a plurality of adjacent tooth portions. Periodontal diagnosis support method. The periodontal disease diagnosis support method according to claim 11 or 12, wherein at least one of the dental image, the information on the shape of the tooth portion, and the quantified alveolar bone resorption degree is displayed on the display unit. . As information on the shape of the tooth portion, the position of the alveolar bone crest portion, the position of the tooth bone tip portion, the position of the crown tip portion, any one or more information, a plurality of adjacent The periodontal disease diagnosis support method according to claim 13, wherein the tooth portion is connected and displayed on the display unit. The periodontal disease diagnosis support method according to claim 14, wherein the connection is approximated by a curve and displayed on the display unit.

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