A system and method for predicting the bony expansion amount of the maxillary arch based on digital images.

Abstract

The application provides a system and method for predicting the amount of bone expansion of maxillary expansion based on digital images, which comprises a CBCT image acquisition device, an image correction module, an image measurement module, a data analysis module and a data output module. The CBCT image acquisition device acquires a CBCT image in a natural head position and a bite position of a dental cusp staggered position. The image correction module corrects the head position and obtains a palatal cross-sectional view. The image measurement module measures the depth IDP of the palatine bone pyramid protrusion embedded in the sphenoid ala notch of the pterygopalatine fissure on the palatal cross-section. The data analysis module determines the embedding shape type of the pterygopalatine fissure according to the IDP value. The data output module outputs whether the predicted amount of bone expansion is sufficient according to the type of the pterygopalatine fissure. The system and method can predict the expansion treatment effect of the population with insufficient transverse development of the maxilla by predicting the amount of bone expansion, especially the effect of the micro-implant assisted rapid expansion of the maxilla.

Description

TECHNICAL FIELD

[0001] The present application relates to a system and method for predicting the amount of bone expansion based on digital images, belonging to the technical field of medical science and technology. BACKGROUND

[0002] Maxillary transverse deficiency (MTD) is a common clinical malocclusion, mainly manifested in the following aspects: the width of the upper and lower dental arches is not coordinated, the posterior teeth are reversed, the teeth are crowded, and the upper respiratory tract is narrow. Maxillary expansion can expand the width of the maxilla by separating the midpalatal suture and the surrounding bone suture. Although the midpalatal suture is the direct target of maxillary expansion, the bilateral pterygopalatine suture also provides considerable bone resistance. After successfully opening the midpalatal suture, the expansion force will be directly transmitted to the bilateral pterygoid region, and the pterygopalatine suture of some patients can be separated under the action of bone expansion force, which can significantly promote the expansion of the posterior palatine segment.

[0003] In recent years, the application of miniscrew-assisted rapid palatal expansion (MARPE) in orthodontic clinics has made minimally invasive non-surgical expansion a trend. Although the success rate of MARPE in separating the midpalatal suture in late adolescence and adults has reached 92.5%, the uncertainty of the bone expansion amount generated by adult MARPE is large, and there is currently a lack of sufficient reliable indicators for predicting the bone expansion amount after MARPE separates the midpalatal suture. A considerable number of adult patients have to undergo secondary expansion or switch to surgical assisted expansion due to insufficient expansion, which inevitably leads to increased trauma and treatment costs. In addition, some patients have asymmetric expansion where one side of the expansion is significantly larger than the other side, resulting in suboptimal treatment outcomes.

[0004] Therefore, the prior art cannot predict the expansion effect before MARPE treatment. Thus, by predicting in advance, unnecessary iatrogenic trauma and patient treatment costs can be reduced. SUMMARY

[0005] The present application provides a system and method for predicting the amount of bone expansion of maxillary expansion based on digital images. By predicting the amount of bone expansion, the effectiveness of expansion treatment for people with maxillary transverse deficiency can be predicted, especially the effectiveness of miniscrew-assisted rapid palatal expansion.

[0006] To achieve this purpose, the present application provides the following technical solutions:

[0007] The first aspect of the present application provides a system for predicting the amount of bony expansion of maxillary expansion based on digital images, comprising: a CBCT image acquisition device, an image correction module, an image measurement module, a data analysis module, and a data output module,

[0008] The CBCT image acquisition device acquires a CBCT image in a natural head position with the occlusion in a cusp crossbite position.

[0009] The image correction module corrects the head position and obtains a transverse view of the palate.

[0010] The image measurement module measures the depth of the pterygopalatine fissure palatal conical process embedded in the pterygoid cut of the sphenoid bone (IDP) on the transverse view of the palate.

[0011] The data analysis module determines the type of pterygopalatine fissure according to the IDP value.

[0012] The data output module outputs whether the predicted amount of bony expansion is sufficient according to the type of pterygopalatine fissure.

[0013] The image correction module can obtain the CBCT image taken by the CBCT image acquisition device, the image measurement module can measure the transverse view of the palate corrected by the image correction module, the data analysis module can analyze the values measured by the image measurement module, and the data output module can output the analysis results of the data analysis module.

[0014] Preferably, the image correction module adjusts the median sagittal view through the anterior nasal spine point ANS, the posterior nasal spine point PNS, and the nasal root point N; the transverse view of the palate passes through the anterior nasal spine point ANS and the posterior nasal spine point PNS, and is perpendicular to the median sagittal plane; the coronal view passes through the posterior nasal spine point PNS, and is perpendicular to the median sagittal plane and the transverse plane at the same time.

[0015] Preferably, the image correction module includes a module loaded with Dolphin software.

[0016] Preferably, in the image measurement module, the measurement method of the depth of the pterygopalatine fissure palatal conical process embedded in the pterygoid cut of the sphenoid bone (IDP) includes:

[0017] The pterygopalatine fissure is cut into two sections by the transverse view of the palate, and four marker points a, b, c, and d are marked on each side of the pterygopalatine fissure region on the transverse view of the palate, in order of the last outer point, the first outer point, the last inner point, and the first inner point of the pterygopalatine fissure; the IDP is calculated according to the coordinates of the derived marker points, IDP = (Yb + Yd - Ya - Yc) / 2.

[0018] For individuals with very short pterygoid plates and pterygoid plate lower edges higher than the palate plane, IDP is recorded as 0.

[0019] In this invention, IDP = (Yb + Yd - Ya - Yc) / 2, where Yb, Yd, Ya, and Yc represent the Y-axis coordinates of markers b, d, a, and c, respectively. Preferably, in the data analysis module, the IDP threshold is 1.90 mm. Samples with IDP < 1.90 mm are defined as Class A pterygopalatine sutures, and samples with IDP ≥ 1.90 mm are defined as Class B pterygopalatine sutures. Furthermore, in the data output module, Class A pterygopalatine sutures output a larger bony expansion amount, indicating sufficient expansion, while Class B pterygopalatine sutures output a smaller bony expansion amount, indicating insufficient expansion.

[0020] In this invention, the IDP critical value of 1.90 mm was obtained through analysis of a large number of samples. The specific method is as follows:

[0021] 1. A retrospective study was conducted on 23 adult cases in which the midpalatal suture was successfully opened using the MARPE method for arch expansion. Initial IDP was retrospectively measured on both sides of the pterygopalatine suture in all samples, and the separation status of the pterygopalatine suture at the end of arch expansion (separation / non-separation) was observed.

[0022] 2. Plot the ROC curve of IDP. Using the maximum Youden index method, determine the optimal IDP critical value for pterygopalatine suture separation during IDP prediction of MARPE as 1.90 mm. At this point, the Youden index is 0.673, and the area under the ROC curve (AUC) > 0.90, indicating that this critical value has excellent performance in distinguishing between pterygopalatine suture separation and non-separation.

[0023] In this invention, through a large number of samples, the average arch expansion amounts of the two types of subjects with pterygopalatine sutures were finally determined as follows: for type A subjects, the semilateral arch expansion amounts at the anterior nasal spine point (ANS) and posterior nasal spine point (PNS) output from the pterygopalatine suture were 2.09±0.84 mm and 1.98±0.80 mm, respectively; for type B subjects, the semilateral arch expansion amounts at the anterior nasal spine point (ANS) and posterior nasal spine point (PNS) output from the pterygopalatine suture were 1.48±0.72 mm and 1.00±0.61 mm, respectively.

[0024] A second aspect of the present invention provides a method for predicting the bony expansion amount of the maxillary arch based on digital images, comprising the following steps:

[0025] S1. Acquire CBCT images of the subject with the head in a natural head position and the bite in the intercuspal position;

[0026] S2. Adjust the midsagittal view to pass through the anterior nasal spine point ANS, the posterior nasal spine point PNS, and the nasal root point N; adjust the palatal transverse view to pass through the anterior nasal spine point ANS and the posterior nasal spine point PNS, and be perpendicular to the midsagittal plane; adjust the coronal view to pass through the posterior nasal spine point PNS, and be perpendicular to both the midsagittal plane and the transverse view.

[0027] S3. Measure the depth (IDP) of the palatine bone conus process into the pterygoid notch of the sphenoid bone on the transverse section of the palatine suture.

[0028] S4. Determine the chimerism type of the pterygopalatine suture based on the IDP value;

[0029] S5. Output whether the predicted bony expansion amount is sufficient based on the pterygopalatine suture type.

[0030] Preferably, in step S3, the method for measuring the depth IDP of the palatine conus process embedding into the pterygoid notch of the sphenoid bone includes:

[0031] The pterygopalatine suture is divided into inner and outer segments by the palatal cross section. Four marker points a, b, c, and d are marked on each side of the pterygopalatine suture region on the palatal cross section, which are the last outer point, the foremost outer point, the last inner point, and the foremost inner point of the pterygopalatine suture, respectively. The IDP is obtained from the coordinates of the marker points, and IDP = (Yb + Yd - Ya - Yc) / 2.

[0032] Individuals with very short outer wing plates and a lower edge of the outer wing plate higher than the palatal plane are designated as IDP 0.

[0033] Preferably, in step S4, the IDP threshold value is 1.90 mm. Samples with IDP < 1.90 mm are defined as Class A pterygopalatine sutures, and samples with IDP ≥ 1.90 mm are defined as Class B pterygopalatine sutures.

[0034] Preferably, in step S5, the output of the pterygopalatine suture in type A is a large amount of bony expansion, which is sufficient, while the output of the pterygopalatine suture in type B is a small amount of bony expansion, which is insufficient.

[0035] A third aspect of the present invention provides a treatment plan recommendation model, including the system for predicting the amount of bony expansion of the maxilla based on digital images as described in the present invention, wherein the model recommends treatment plans based on the amount of bony expansion output by the system, and the recommended treatment plans include: mini-implant-assisted rapid maxillary expansion, or surgical-assisted maxillary expansion.

[0036] Preferably, when the system determines that the subject has a Class A pterygopalatine suture, the recommended treatment is microimplant-assisted rapid maxillary expansion.

[0037] Preferably, when the system determines that the subject has a Class B pterygopalatine suture, the recommended treatment is surgical-assisted maxillary expansion.

[0038] Compared with the prior art, the beneficial effects and significant progress of applying the technical solution of the present invention are as follows:

[0039] 1. This invention establishes a new classification parameter based on the morphology of the pterygopalatine suture to assist in predicting the efficacy of maxillary expansion, improves the accuracy of predicting the amount of bony expansion, guides the formulation of maxillary expansion treatment plans, and is expected to reduce unnecessary iatrogenic trauma and patient treatment expenses.

[0040] 2. The system and method for predicting the amount of bony expansion of the maxilla based on digital images provided by the present invention can predict the effect of expansion treatment for people with insufficient transverse development of the maxilla by predicting the amount of bony expansion, especially the effect of micro-implant-assisted rapid expansion of the maxilla.

[0041] 3. The treatment plan recommendation model provided by this invention can recommend the best treatment plan for patients and improve treatment results. Attached Figure Description

[0042] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly described below.

[0043] Figure 1 This is a flowchart of the method in Example 2;

[0044] Figure 2 This is the head position correction and reference plane diagram of Example 2, where A is the cross section (APP), B is the midsagittal plane, and C is the coordinate axis and reference plane;

[0045] Figure 3 This is a simplified diagram of IDP measurement in Example 2, where the red bone block represents the sphenoid bone, the blue bone block represents the remaining craniofacial bones, A is the bottom view of the palate in three-dimensional space, B is the top view of the palate, and C is the pterygopalatine suture marker point used for IDP measurement.

[0046] Figure 4 These are images of the pterygopalatine suture with different IDP values ​​in Example 2. Figures A and H are sorted from smallest to largest IDP value. Figures A–D represent type A pterygopalatine sutures: IDP < 1.90 mm; Figure EH represents type B pterygopalatine sutures: IDP ≥ 1.90 mm.

[0047] Figure 5 This is the ROC curve for IDP prediction of pterygopalatine suture separation during arch expansion;

[0048] Figure 6 These are maxillary arch expansion diagrams of the A and B pterygopalatine suture samples from Example 2, where Figure A shows the A pterygopalatine suture and Figure B shows the B pterygopalatine suture.

[0049] Figure 7 These are images of the patient before and after arch expansion in Example 3;

[0050] Figure 8 These are images of the patient before and after arch expansion in Example 4;

[0051] Figure 9 These are images of the patient before and after arch expansion in Example 5. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the present invention is further described below in conjunction with specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or as recommended by the manufacturer. Unless otherwise stated, percentages and parts are weight percentages and parts by weight. Unless otherwise specified, the experimental materials and reagents used in the following embodiments are commercially available.

[0053] Unless otherwise specified, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should be noted that the terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the exemplary embodiments of this application.

[0054] To better understand this invention, the technical terms used in this invention will be explained below.

[0055] ANS, anterior nasal spine, is the tip of the anterior nasal spine. The anterior nasal spine is often used as one of the two landmarks for determining the palatal plane.

[0056] PNS, posterior nasal spine.

[0057] N, nasion, the root of the nose.

[0058] The sagittal plane is a longitudinal section that divides the human body into left and right parts along the front-back direction.

[0059] A cross section is a section perpendicular to the centerline direction through the centerline stake. Cross section measurement involves measuring the ground elevation at the centerline stake perpendicular to the centerline direction (normal direction). When conducting cross section measurement, the direction of the cross section must first be determined, and then the distance and elevation difference between the ground change points on both sides of the centerline stake and the stake point are measured in this direction, thereby drawing a cross section diagram.

[0060] The coronal plane is a cross-section that longitudinally divides the human body into front and back parts along the left and right directions.

[0061] Example 1

[0062] A system for predicting the amount of bony expansion in the maxilla based on digital images includes: a CBCT image acquisition device, an image correction module, an image measurement module, a data analysis module, and a data output module. The CBCT image acquisition device captures CBCT images of the maxilla in a natural head position with the occlusion in an intercuspal position. The image correction module corrects the head position and acquires a transverse view of the palate. The image measurement module measures the depth (IDP) of the palatine conus into the pterygoid notch of the sphenoid bone in the transverse view of the palate. The data analysis module determines the occlusal morphology type of the pterygoid suture based on the IDP value. The data output module outputs the predicted amount of bony expansion based on the pterygoid suture type. The image correction module acquires CBCT images captured by the CBCT image acquisition device, the image measurement module measures the transverse view of the palate corrected by the image correction module, the data analysis module analyzes the values ​​measured by the image measurement module, and the data output module outputs the analysis results from the data analysis module.

[0063] In this embodiment, the image correction module adjusts the midsagittal view to pass through the anterior nasal spine point (ANS), the posterior nasal spine point (PNS), and the nasal root point (N); the palatal transverse view passes through the anterior nasal spine point (ANS) and the posterior nasal spine point (PNS), and is perpendicular to the midsagittal plane; the coronal view passes through the posterior nasal spine point (PNS), and is perpendicular to both the midsagittal plane and the transverse view.

[0064] In this embodiment, the image correction module includes a module loaded with Dolphin software.

[0065] In this embodiment, the method for measuring the depth IDP of the palatine bone conus process embedded in the pterygoid notch of the pterygoid suture in the image measurement module includes: the pterygoid suture is divided into inner and outer segments by the transverse section of the palate, and four marker points a, b, c, and d are marked on each side of the pterygoid suture region on the transverse section of the palate, which are the last outer point, the foremost outer point, the last inner point, and the foremost inner point of the pterygoid suture, respectively; the IDP is obtained according to the coordinates of the derived marker points, IDP = (Yb + Yd - Ya - Yc) / 2; for individuals with very short outer pterygoid plates and lower edges of outer pterygoid plates higher than the palatal plane, the IDP is recorded as 0.

[0066] In this embodiment, in the data analysis module, the IDP threshold value is 1.90 mm. Samples with IDP < 1.90 mm are defined as Class A pterygopalatine sutures, and samples with IDP ≥ 1.90 mm are defined as Class B pterygopalatine sutures. In the data output module, the hemispherical expansion amounts at the anterior nasal spine point (ANS) and posterior nasal spine point (PNS) output for Class A pterygopalatine sutures are 2.09 ± 0.84 mm and 1.98 ± 0.80 mm, respectively, while the hemispherical expansion amounts at the anterior nasal spine point (ANS) and posterior nasal spine point (PNS) output for Class B pterygopalatine sutures are 1.48 ± 0.72 mm and 1.00 ± 0.61 mm, respectively.

[0067] This embodiment provides a method for predicting the bony expansion amount of the maxillary arch based on digital images, comprising the following steps:

[0068] S1. Acquire CBCT images of the subject with the head in a natural head position and the bite in the intercuspal position;

[0069] S2. Adjust the midsagittal view to pass through the anterior nasal spine point ANS, the posterior nasal spine point PNS, and the nasal root point N; adjust the palatal transverse view to pass through the anterior nasal spine point ANS and the posterior nasal spine point PNS, and be perpendicular to the midsagittal plane; adjust the coronal view to pass through the posterior nasal spine point PNS, and be perpendicular to both the midsagittal plane and the transverse view.

[0070] S3. Measure the depth (IDP) of the palatine bone conus process into the pterygoid notch of the sphenoid bone on the transverse section of the palatine suture.

[0071] S4. Determine the chimerism type of the pterygopalatine suture based on the IDP value;

[0072] S5. Output the predicted bony expansion amount based on the pterygopalatine suture type.

[0073] Example 2

[0074] like Figure 1 As shown, the system and method of Example 1 were used to conduct experiments on subjects, and the specific methods are as follows.

[0075] Step 1: Instruct the patient to have CBCT images taken (voxel slice thickness ≤ 0.30 mm), and export the image files in DICOM format.

[0076] CBCT images were acquired using a KaVo OP 3D Vision (KaVo, Biberach, Germeny) with the following scanning parameters: tube voltage 110kV, tube current 2.81mA, voxel slice thickness ≤0.3mm, and scan time 8.9s. The scanning field of view was 23*17cm. During the examination, the patient was upright with the head in a natural head position, the mandible fixed with a chin rest, and the occlusion in the intercuspal position.

[0077] Step 2: Obtain a cross-sectional view of the palate.

[0078] like Figure 2As shown, head position was corrected using Dolphin software (version 11.9; Dolphin Imaging & Management Solutions, Chatsworth, CA, USA). The midsagittal plane was adjusted to pass through the anterior nasal spine (ANS), posterior nasal spine (PNS), and nasal root (N); the axial palatal plane (APP) passed through the ANS and PNS and was perpendicular to the midsagittal plane; the coronal plane passed through the PNS and was perpendicular to both the midsagittal and axial planes. Figure 2 In the diagram, 2A is the cross section (APP), 2B is the midsagittal plane, and 2C is the coordinate axis and reference plane.

[0079] Step 3: Measure the depth (IDP) of the palatine conus process into the pterygoid notch of the sphenoid bone on the transverse section of the palatine.

[0080] like Figure 3 As shown in Figure C, the insertion depth of the pyramidal process into the pterygoid notch (IDP) is defined as the sagittal distance between the midpoints of the anterior and posterior edges of the portion of the palatine pyramidal process that is inserted into the pterygoid notch of the sphenoid bone. The specific measurement method is as follows:

[0081] 1. The pterygopalatine suture is divided into inner and outer segments by the transverse section of the palate. Figure 3 AB). Mark four landmarks (marker ad) on each side of the pterygopalatine suture region on the transverse section of the palate, in the following order: the last outer point of the pterygopalatine suture, the most anterior outer point, the last inner point, and the most anterior inner point.

[0082] 2. Calculate IDP based on the derived coordinates of the marker points, where IDP = (Yb + Yd - Ya - Yc) / 2.

[0083] 3. For a small number of individuals with very short outer wing plates and lower edges of the outer wing plates above the palatal plane, the IDP is recorded as 0.

[0084] Step 4: Determine the chimerism classification of the pterygopalatine suture based on the IDP value.

[0085] The critical value for IDP is 1.90 mm. Samples with IDP < 1.90 mm are defined as Class A pterygopalatine sutures, and samples with IDP ≥ 1.90 mm are defined as Class B pterygopalatine sutures. Figure 4 ).

[0086] The method for obtaining the IDP threshold is as follows:

[0087] 1. A retrospective study was conducted on 23 adult cases in which the midpalatal suture was successfully opened using the MARPE method for arch expansion. Initial IDP was retrospectively measured on both sides of the pterygopalatine suture in all samples, and the separation status of the pterygopalatine suture at the end of arch expansion (separation / non-separation) was observed.

[0088] 2. Plot the ROC curve of IDP. Using the maximum Youden index method, determine the optimal IDP critical value for predicting pterygopalatine suture separation during MARPE using IDP. The critical value is 1.90 mm, at which point the Youden index is 0.673, and the area under the ROC curve (AUC) > 0.90, indicating that this critical value has excellent performance in distinguishing between pterygopalatine suture separation and its absence. Figure 5 ).

[0089] Step 5: Use pterygopalatine suture morphology classification to assist in estimating the bony expansion amount and maxillary expansion pattern using the MARPE method.

[0090] Under the expanding force provided by the MARPE bone anchorage, the pterygopalatine suture of type A tends to separate, thereby releasing the pterygopalatine lock and producing a greater amount of bony expansion of the midpalatal suture; while the pterygopalatine suture of type B is difficult to separate, and the pterygopalatine lock tends to restrict the bony expansion of the maxilla.

[0091] The retrospective cohort showed that the mean expansion of the mid-palatal suture at the ANS and PNS in the A group samples was 2.09±0.84 mm and 1.98±0.80 mm, respectively, while the mean expansion of the mid-palatal suture at the ANS and PNS in the B group samples was 1.48±0.72 mm and 1.00±0.61 mm, respectively; the difference between the two groups was statistically significant.

[0092] Individuals with bilateral pterygopalatine sutures classified as either category A or B are more likely to experience asymmetrical expansion. For adult patients with severe maxillary metatarsal disease (MTD), if the bilateral pterygopalatine sutures are classified as category B, achieving sufficient bony expansion via MARPE is expected to be challenging. It is recommended to release bony expansion resistance to varying degrees through surgery under local or general anesthesia before performing maxillary expansion. Future prospective studies with larger sample sizes are necessary to provide high-quality evidence-based support for the feasibility and reliability of applying this pterygopalatine suture morphology classification index in orthodontic clinical practice. Figure 6 ).

[0093] Example 3

[0094] This embodiment is a practical application of the method of the present invention.

[0095] Subject information: Female, 29 years old.

[0096] Using the method described in Example 1, the patient's right pterygopalatine suture IDP was 2.35 mm, belonging to category B; the left pterygopalatine suture IDP was 0 mm, belonging to category A. The patient underwent rapid arch expansion for half a month using an MSE-II type expander at a rate of 0.53 mm / d, followed by CBCT imaging.

[0097] The results are as follows Figure 7 As shown, where, Figure 7 (Left) CBCT overlap before and after expansion (before expansion: gray; after expansion: red). Figure 7 (Middle) is CBCT before arch expansion. Figure 7 (Right) CBCT after arch expansion. The CBCT shows that the right pterygopalatine suture is not separated, while the left pterygopalatine suture is separated; the right mid-palatal suture has been significantly expanded more than the left, and only the right posterior crossbite has been relieved, showing asymmetrical arch expansion.

[0098] Example 4

[0099] This embodiment is a practical application of the method of the present invention.

[0100] Subject information: Female, 24 years old.

[0101] Using the method described in Implementation 1, the patient's right pterygopalatine suture IDP was 1.26 mm, classified as Category A; the left pterygopalatine suture IDP was 1.80 mm, also classified as Category A. The patient underwent continuous rapid arch expansion for half a month using an MSE-II type expander at a rate of 0.53 mm / d, followed by CBCT imaging after the expansion was completed.

[0102] The results are as follows Figure 8 As shown, where, Figure 8 (Left) CBCT overlap before and after expansion (before expansion: gray; after expansion: red). Figure 8 (Middle) is CBCT before arch expansion. Figure 8 (Right) is the CBCT after arch expansion. On the transverse section of the palate in the CBCT, separation of the bilateral pterygopalatine sutures can be seen; the total arch expansion at the mid-palatine suture at the ANS and PNS is 3.7 mm and 4.0 mm, respectively, with the bilateral arch expansion being basically symmetrical, and bilateral posterior crossbite resection is removed.

[0103] Example 5

[0104] This embodiment is a practical application of the method of the present invention.

[0105] Subject information: Male, 22 years old.

[0106] Using the method described in Implementation 1, the patient's right pterygopalatine suture IDP was 2.33 mm, classified as category B; the left pterygopalatine suture IDP was 1.92 mm, also classified as category B. A type MSE-II expander was used to rapidly expand the expander for half a cycle at a rate of 0.53 mm / d, and CBCT was then performed after the expansion was completed.

[0107] The results are as follows Figure 9 As shown, where, Figure 9 (Left) CBCT overlap before and after expansion (before expansion: gray; after expansion: red). Figure 9 (Middle) is CBCT before arch expansion. Figure 9 (Right) CBCT after arch expansion. The CBCT shows that the bilateral pterygopalatine sutures were not separated. The total arch expansion at the ANS and PNS of the mid-palatine sutures was 2.2 mm and 2.3 mm, respectively. The skeletal expansion of the mid-palatine suture was relatively small, but the arch expansion on both sides was basically symmetrical. The bilateral posterior crossbite was not completely resolved.

[0108] Therefore, if it is predicted in advance that the subject has a type B pterygopalatine suture based on the image data of the subject in this embodiment, it can be recommended to perform surgical procedures under local or general anesthesia to release the bony expansion resistance to varying degrees before performing maxillary expansion. This can also avoid the situation where the expansion is unsuccessful in this embodiment.

[0109] The applicant declares that, in the process of describing the above-mentioned specification:

[0110] The terms "this embodiment," "an embodiment of the present invention," "as shown," "further," and "further improved technical solutions," etc., indicate that the specific features, structures, materials, or characteristics described in the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms are not necessarily directed at the same embodiment or example, and the specific features, structures, materials, or characteristics described can be combined or combined in any suitable manner in one or more embodiments or examples. Furthermore, without causing contradiction, those skilled in the art can combine or combine the different embodiments or examples described in this specification and the features of the different embodiments or examples.

[0111] Finally, it should be noted that:

[0112] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them;

[0113] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention. Non-essential improvements, adjustments or substitutions made by those skilled in the art based on the content of this specification are all within the scope of protection claimed by the present invention.

Claims

1. A system for predicting the amount of bony expansion of the maxillary arch for expansion based on digital images, characterized by, It comprises: a CBCT image acquisition device, an image correction module, an image measurement module, a data analysis module, and a data output module, the CBCT image acquisition device acquires a CBCT image in a natural head position and a bite position of a tooth tip cross position; the image correction module corrects the head position and acquires a palatal cross-sectional view; the image measurement module measures the depth IDP of the palatine bone pyramid process embedded in the pterygoid process notch of the sphenoid bone on the palatal cross section; the data analysis module determines the embedding shape type of the pterygopalatine suture according to the IDP value; the data output module outputs whether the predicted bone expansion amount is sufficient according to the type of the pterygopalatine suture; The image correction module can acquire the CBCT image taken by the CBCT image acquisition device, the image measurement module can measure the palatal cross-sectional view corrected by the image correction module, the data analysis module analyzes the value measured by the image measurement module, and the data output module outputs the analysis result of the data analysis module; The depth IDP of the pterygopalatine suture pyramid process embedded in the pterygoid process notch is defined as the sagittal distance between the midpoint of the anterior and posterior edges of the part of the palatine bone pyramid process embedded in the pterygoid process notch of the sphenoid bone; In the image measurement module, the measurement method of the depth IDP of the palatine bone pyramid process embedded in the pterygoid process notch of the sphenoid bone in the pterygopalatine suture comprises: The pterygopalatine suture is cut into two sections by the palatal cross section, and four marker points a, b, c, and d are marked on each side of the pterygopalatine suture area on the palatal cross section, which are the last outer point, the first outer point, the last inner point, and the first inner point of the pterygopalatine suture, respectively. The IDP is calculated according to the coordinates of the derived marker points, IDP = (Yb + Yd - Ya - Yc) / 2; wherein Yb, Yd, Ya and Yc represent the Y-axis coordinate values of the b, d, a and c marker points, respectively; The IDP is recorded as 0 for individuals with very short pterygoid plate and pterygoid plate lower edge higher than the palatal plane.

2. The system for predicting the bony expansion amount of maxillary expansion based on digital images according to claim 1, wherein, The image correction module adjusts the median sagittal view through the anterior nasal spine point ANS, the posterior nasal spine point PNS and the nasal root point N; the palatal cross-sectional view passes through the anterior nasal spine point ANS and the posterior nasal spine point PNS, and is perpendicular to the median sagittal plane; the coronal view passes through the posterior nasal spine point PNS, and is perpendicular to the median sagittal plane and the cross section at the same time.

3. The system for predicting the bony expansion amount of maxillary expansion based on digital images according to claim 1 or 2, characterized in that, The image correction module comprises a module loaded with Dolphin software.

4. The system for predicting the bone expansion amount of maxillary expansion according to claim 1, wherein In the data analysis module, the IDP critical value is 1.90mm, the sample with IDP <1.90mm is defined as type A pterygopalatine suture, and the sample with IDP ≥1.90mm is defined as type B pterygopalatine suture; and In the data output module, type A pterygopalatine suture outputs larger bone expansion amount, and the expansion amount is sufficient, and type B pterygopalatine suture outputs smaller bone expansion amount, and the expansion amount is insufficient.

5. A method of predicting the amount of bony expansion of the maxillary arch for expansion based on digital images, characterized in that, The steps comprise: S1, acquiring a CBCT image of a subject's head in a natural head position and a bite position of a tooth tip cross position; S2, the median sagittal view is adjusted through the anterior nasal spine point ANS, the posterior nasal spine point PNS and the nasion point N; the palatal transverse view is through the anterior nasal spine point ANS, the posterior nasal spine point PNS, and is perpendicular to the median sagittal plane; the coronal view is through the posterior nasal spine point PNS, and is perpendicular to the median sagittal plane and the transverse plane at the same time; S3, the depth IDP of the pterygopalatine fissure palatal pyramid embedded in the pterygoid notch of the sphenoid bone is measured on the palatal transverse plane; S4, the pterygopalatine fissure type is determined according to the IDP value; S5, the predicted bone expansion amount is output according to the pterygopalatine fissure type; The depth IDP of the pterygopalatine fissure palatal pyramid embedded in the pterygoid notch of the sphenoid bone is defined as the sagittal distance between the midpoint of the anterior and posterior edges of the part embedded in the pterygoid notch of the sphenoid bone; In step S3, the measurement method of the depth IDP of the pterygopalatine fissure palatal pyramid embedded in the pterygoid notch of the sphenoid bone includes: The pterygopalatine fissure is cut into two sections by the palatal transverse plane, and four landmark points a, b, c, d are marked on each side of the pterygopalatine fissure region on the palatal transverse plane, which are the last outer point, the first outer point, the last inner point and the first inner point of the pterygopalatine fissure in turn; IDP is calculated according to the derived landmark point coordinates, IDP = (Yb + Yd - Ya - Yc) / 2; wherein Yb, Yd, Ya and Yc represent the Y-axis coordinate values of the b, d, a and c landmark points respectively; The pterygoid plate is very small, and the lower edge of the pterygoid plate is higher than the palatal plane, and IDP is recorded as 0.

6. The method of predicting the amount of bony expansion of the maxillary arch based on digital images of claim 5, wherein, In step S4, the IDP critical value is 1.90 mm, the sample with IDP <1.90 mm is defined as type A pterygopalatine fissure, and the sample with IDP ≥1.90 mm is defined as type B pterygopalatine fissure.

7. The method of predicting the amount of bony expansion of the maxillary arch based on digital images of claim 6, wherein, In step S5, the type A pterygopalatine fissure outputs a larger bone expansion amount, and the expansion amount is sufficient, and the type B pterygopalatine fissure outputs a smaller bone expansion amount, and the expansion amount is insufficient.

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