CN104915519B - A kind of cranio-maxillofacial method for establishing model and device - Google Patents

Abstract

This application discloses a method and device for establishing a craniomaxillofacial bone model. The method includes: using the three-dimensional digital images of the test sample's jaw and remaining craniomaxillofacial bone to generate a corresponding three-dimensional finite element model of the jaw and the remaining craniomaxillofacial bone. According to the anatomical structure of the maxillofacial bone, combine the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the remaining cranio-maxillofacial bone to obtain the three-dimensional finite element model of the cranio-maxillofacial bone. The parameters of the three-dimensional finite element model are set, such as the contact type between the jaw and the rest of the craniomaxillofacial bone, the boundary conditions of the jaw displacement, etc. Since the three-dimensional finite element model of the craniofacial bone established by this application includes the complete anatomical shape of the cranial and maxillofacial bone, when the three-dimensional finite element model of the craniofacial bone established by the method of this application is used to simulate the impact test, it can not only simulate the impact of the jaw It can also analyze the stress transmission of the remaining cranial and maxillofacial bones, which has higher test simulation and stronger clinical guiding significance.

Description

A method and device for establishing a craniofacial bone model

technical field

The present application relates to the technical field of model building, and more specifically, to a method and device for building a craniomaxillofacial bone model.

Background technique

Traffic accident injuries have always been one of the main causes of oral and maxillofacial injuries in the peaceful era. With the increasing popularity of motor vehicles as a means of transportation, the incidence of traffic accident injuries has increased year by year. Maxillofacial traffic accident injuries are mainly caused by impact. Clinical data show that maxillofacial impact injuries can not only cause local damage to the maxillofacial region, but also damage adjacent organs, such as the brain, eyeballs, inner ear, etc., making the injury more serious and complicated, and the mortality rate also increases increase.

In order to better guide the clinical treatment of maxillofacial injuries, several maxillofacial impact injury research mechanisms are provided in the prior art, all of which are aimed at creating a single jaw model, and simulate the impact on the created single jaw model Experiment and get the experimental results.

The inventors of this case found that it has the following disadvantages by studying the prior art: since any jaw is connected to other jaws through a specific anatomical structure, when the jaw is subjected to a mechanical load, it can be dissected. The connection transmits stress to the other jaws, resulting in a reduction in its own force and causing mechanical changes in the surrounding jaws. Therefore, when the single jaw bone model created according to the prior art is used for the simulated impact experiment, the simulation performance of the experiment is not high, and the stress conduction analysis of the rest of the craniomaxillofacial bone cannot be simulated.

Contents of the invention

In view of this, the present application provides a craniomaxillofacial bone model establishment method and device, which are used to solve the problem of low experimental simulation performance when the existing single jaw bone model is used for simulated impact experiments.

In order to achieve the above purpose, the proposed scheme is as follows:

A method for establishing a craniofacial bone model, comprising:

Obtaining a three-dimensional digital image of the jaw and remaining cranio-maxillofacial bone of the test sample;

Using the three-dimensional digital image of the jaw to generate a three-dimensional finite element model of the jaw, and using the three-dimensional digital image of the remaining craniomaxillofacial bone to generate a three-dimensional finite element model of the remaining craniomaxillofacial bone;

According to the maxillofacial anatomical structure, combining the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the remaining cranio-maxillofacial bone to obtain the three-dimensional finite element model of the cranio-maxillofacial bone;

Parameters are set for the three-dimensional finite element model of the craniomaxillofacial bone, and the parameters include the contact type between the jaw and the rest of the craniomaxillofacial bone, and the boundary conditions of the jaw displacement.

Preferably, the jaw bone is the mandible, and the remaining craniomaxillofacial bone is a craniomaxillary complex, and then the three-dimensional digital images of the jaw bone and the remaining craniomaxillofacial bone of the test sample obtained include:

Obtain the maxillofacial thin layer CT scan image of the test sample;

According to the tissue threshold of the mandible and the craniomaxillary complex, the mandibular bone cloud map and the craniomaxillary complex cloud map were screened out respectively;

Three-dimensional reconstruction is performed on the mandibular skeleton cloud image and the craniomaxillary complex cloud image respectively to obtain three-dimensional digital images of the mandible and the cranio-maxillary complex.

Preferably, the jaw bone is the mandible, and the remaining craniomaxillofacial bone is a craniomaxillary complex, then the three-dimensional finite element model of the remaining craniomaxillofacial bone is generated using the three-dimensional digital image of the remaining craniomaxillofacial bone, include:

The 3D digital image of the craniomaxillary complex is subjected to face mesh division to obtain a craniomaxillary complex face mesh model.

Preferably, the jaw is the mandible, and the rest of the craniomaxillofacial bone is a craniomaxillary complex, then the use of the three-dimensional digital image of the jaw to generate a three-dimensional finite element model of the jaw includes:

Performing face mesh division on the three-dimensional digital image of the mandible to obtain a mandible face mesh model;

Perform surface calculation on the mandibular surface mesh model to obtain a nurbs surface;

Create a mandible CAD three-dimensional solid model according to the nurbs surface;

The mandible CAD three-dimensional solid model is divided into volume grids to obtain the mandible volume grid model.

Preferably, the body mesh division is carried out to the mandible CAD three-dimensional solid model to obtain the mandible body mesh model, including:

Determining the boundary outline of the mandibular CAD three-dimensional solid model, and performing geometric cleaning;

According to preset rules, the CAD three-dimensional solid model of the mandible is divided into blocks;

Carry out volume mesh division for each block;

Combining the divided blocks of the body mesh to obtain the mandible body mesh model.

A craniomaxillofacial bone model building device, comprising:

An image acquisition unit, configured to acquire a three-dimensional digital image of the test sample's jaw and remaining craniomaxillofacial bone;

A jaw model generating unit, configured to generate a three-dimensional finite element model of the jaw using the three-dimensional digital image of the jaw;

A remaining craniomaxillofacial bone model generating unit, configured to generate a three-dimensional finite element model of the remaining craniomaxillofacial bone using the three-dimensional digital image of the remaining craniomaxillofacial bone;

A model combination unit, configured to combine the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the rest of the cranio-maxillofacial bone according to the anatomical structure of the maxillofacial bone to obtain the three-dimensional finite element model of the cranio-maxillofacial bone;

The model parameter setting unit is used to set the parameters of the three-dimensional finite element model of the cranio-maxillofacial bone, and the parameters include the contact type between the jaw and the rest of the cranio-maxillofacial bone, and the boundary conditions of the jaw displacement.

Preferably, the jaw is the mandible, and the remaining craniomaxillofacial bone is the craniomaxillary complex, then the image acquisition unit includes:

A CT image acquisition unit, configured to acquire a maxillofacial thin-slice CT scan image of a test sample;

The image screening unit is used to filter out the mandibular bone cloud map and the craniomaxillary complex cloud map respectively according to the tissue threshold of the mandible and the craniomaxillary complex;

The three-dimensional reconstruction unit is used to respectively perform three-dimensional reconstruction on the cloud image of the mandible bone and the cloud image of the craniomaxillary complex to obtain three-dimensional digital images of the mandible and the cranio-maxillary complex.

Preferably, the jaw bone is the mandible, and the remaining craniomaxillofacial bone is a craniomaxillary complex, then the remaining craniomaxillofacial bone model generation unit includes:

The first remaining craniomaxillofacial bone model generating subunit is used to divide the three-dimensional digital image of the craniomaxillary complex into a facial mesh to obtain a cranial maxillofacial complex facial mesh model.

Preferably, the jaw is a mandible, and the remaining craniomaxillofacial bone is a craniomaxillary complex, then the jaw model generation unit includes:

The first jawbone model generating subunit is used to perform surface mesh division on the three-dimensional digital image of the mandible to obtain a mandible surface mesh model;

The second jaw model generation subunit is used to perform surface calculation on the mandibular surface mesh model to obtain a nurbs surface;

The third jawbone model generates a subunit, which is used to create a mandible CAD three-dimensional solid model according to the nurbs surface;

The fourth jawbone model generating subunit is used for performing volume grid division on the mandible CAD three-dimensional solid model to obtain a mandible volume grid model.

Preferably, the fourth jaw model generation subunit includes:

A contour line determining unit, configured to determine the boundary contour line of the mandible CAD three-dimensional solid model, and perform geometric cleaning;

A block processing unit, configured to block the CAD three-dimensional solid model of the mandible according to preset rules;

A volume grid division unit, used for volume grid division of each block;

The block combination unit is used to combine the blocks after the body mesh is divided to obtain the mandible body mesh model.

It can be seen from the above technical solutions that the method for establishing a craniofacial bone model provided by the embodiment of the present application uses the three-dimensional digital images of the jaw bone and remaining cranio-maxillofacial bone of the test sample to generate a corresponding three-dimensional finite element model of the jaw bone and A three-dimensional finite element model of the remaining craniofacial bone, and according to the anatomical structure of the maxillofacial region, combine the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the remaining cranial and maxillofacial bone to obtain a three-dimensional finite element model of the maxillofacial bone , and finally perform parameter setting on the three-dimensional finite element model of the maxillofacial bone, such as setting the contact type between the jaw and the rest of the craniomaxillofacial bone, the boundary conditions of the jaw displacement, and the like. Since the three-dimensional finite element model of the maxillofacial bone established by this application includes the jaw and the rest of the craniofacial bone, it is a complex that includes the complete anatomical shape of the cranial and maxillofacial bone. The three-dimensional finite element model can be used for crash tests under various conditions, and when simulating a crash test, it can not only simulate the complete morphology of the bone damage after the impact of the jaw, but also analyze the stress conduction of the remaining cranial and maxillofacial bones. The simulation is higher and the clinical guidance is stronger.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present application, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Fig. 1 is a flow chart of a method for establishing a craniofacial bone model disclosed in the embodiment of the present application;

Fig. 2 is a flow chart of another craniofacial bone model establishment method disclosed in the embodiment of the present application;

Fig. 3 is a flow chart of another craniofacial bone model establishment method disclosed in the embodiment of the present application;

Fig. 4 is a flowchart of another craniofacial bone model establishment method disclosed in the embodiment of the present application;

Fig. 5 is a flow chart of a method for body meshing of a mandible CAD three-dimensional solid model disclosed in an embodiment of the present application;

Fig. 6 is a schematic structural diagram of a device for establishing a craniofacial bone model disclosed in an embodiment of the present application;

FIG. 7 is a schematic structural diagram of an image acquisition unit disclosed in an embodiment of the present application;

Fig. 8 is a schematic diagram of the unit structure of a residual cranial and maxillofacial bone model disclosed in the embodiment of the present application;

Fig. 9 is a schematic structural diagram of a jaw model generating unit disclosed in the embodiment of the present application;

Fig. 10 is a schematic structural diagram of a fourth jaw model generation subunit disclosed in the embodiment of the present application. Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

Referring to FIG. 1 , FIG. 1 is a flowchart of a method for establishing a craniofacial bone model disclosed in an embodiment of the present application.

As shown in Figure 1, the method includes:

Step S100, acquiring a three-dimensional digital image of the jaw and remaining craniomaxillofacial bone of the test sample;

A healthy adult volunteer can be selected to have a CT scan of his head, and after processing, a three-dimensional digital image of the jaw and remaining craniofacial bone can be obtained. Among them, the remaining craniomaxillofacial bones are the rest of the craniomaxillofacial bones except the test sample jaw. If the test sample jaw is the mandible, the remaining craniomaxillofacial bones include the maxilla, zygomatic bone, and temporal bone. Wait.

Step S110, using the three-dimensional digital image of the jaw to generate a three-dimensional finite element model of the jaw;

Step S120, using the three-dimensional digital image of the remaining craniofacial bone to generate a three-dimensional finite element model of the remaining craniomaxillofacial bone;

The finite element model regards the entire object structure as a geometric entity composed of a finite number of small units connected to each other, and the final assembly effect of the mechanical characteristics of each unit reflects the overall mechanical properties of the structure. The finite element model can analyze complex mechanical processes in and between objects, predict the effects of mechanical actions (such as changes in model stress, strain, shape, temperature, etc.), and can visually display or output calculation results on the computer for future use. analyze.

Step S130, combining the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the remaining cranio-maxillofacial bone according to the anatomical structure of the maxillofacial bone to obtain a three-dimensional finite element model of the cranio-maxillofacial bone;

Step S140, setting parameters for the three-dimensional finite element model of the craniomaxillofacial bone.

After the parameters of the three-dimensional finite element model of the craniomaxillofacial bone are set, the model can be used for the collision test. Wherein, the parameters may include the type of contact between the jaw and the rest of the craniomaxillofacial bone, and the boundary conditions of the jaw displacement. In addition, some basic parameters can also be included, such as maxillofacial bone material properties, impactor material properties, impactor section properties, impactor load type and loading mode, material failure mode, etc.

The craniomaxillofacial bone model establishment method provided in the embodiment of the present application uses the three-dimensional digital images of the test sample jaw and remaining craniomaxillofacial bone to generate the corresponding three-dimensional finite element model of the jaw and the three-dimensional finite element model of the remaining craniomaxillofacial bone , and according to the anatomical structure of the maxillofacial bone, combine the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the remaining craniofacial bone to obtain the three-dimensional finite element model of the maxillofacial bone, and finally calculate the three-dimensional finite element model of the maxillofacial bone The parameters of the finite element model are set, such as the contact type between the jaw and the rest of the craniomaxillofacial bone, the boundary conditions of the jaw displacement, etc. Since the three-dimensional finite element model of the maxillofacial bone established by this application includes the jaw and the rest of the craniofacial bone, it is a complex that includes the complete anatomical shape of the cranial and maxillofacial bone. The three-dimensional finite element model can be used for crash tests under various conditions, and when simulating a crash test, it can not only simulate the complete morphology of the bone damage after the impact of the jaw, but also analyze the stress conduction of the remaining cranial and maxillofacial bones. The simulation is higher and the clinical guidance is stronger.

Optionally, let’s take Hypermesh (HM) software as an example for parameter setting, and its parameter setting method is as follows:

This application adopts the contact type of *CONTACT_AUTOMATIC_GENERAL_ID contact setting;

Set the jaw model and the material properties of the impactor, and select the appropriate material constitutive equation according to the model and material properties;

To set the section properties of the impactor, set the keyword *SECTION_SOLID in HM;

Set the jaw displacement boundary condition, and set the *BOUNDARY_SPC_SET keyword in HM;

Set the load type and load mode:

Set the *INITIAL_VELOCITY_GENERATION keyword in HM, and the load method is to apply initial velocity load to the projectile;

To set the material failure mode:

Control the *CONSTRAINED_TIED_NODES_FAILURE keyword in HM.

Optionally, in the above-mentioned embodiments of the present application, during the process of establishing the craniofacial bone model, a three-dimensional finite element model is respectively established for the jaw and remaining cranio-maxillofacial bone, and then combined. Wherein, the jaw can be a mandible, a maxilla or a collection of maxilla and mandible. For the convenience of explanation, the mandible is taken as an example below, and the corresponding remaining craniomaxillofacial bone is the craniomaxillary complex.

Referring to FIG. 2 , FIG. 2 is a flow chart of another craniofacial bone model establishment method disclosed in the embodiment of the present application.

As shown in Figure 2, the method includes:

Step S200, acquiring the maxillofacial thin-layer CT scan image of the test sample;

Specifically, the CT scan images can be stored in DICOM format.

Step S210, according to the tissue thresholds of the mandible and the craniomaxillary complex, respectively filter out the mandibular skeleton cloud map and the craniomaxillary complex cloud map;

What needs to be explained is that the tissue threshold is also the gray value of the tissue. The gray value of different tissues is different. Based on this, the mandibular bone cloud map and the craniomaxillary complex cloud map can be filtered out.

Step S220, performing three-dimensional reconstruction on the cloud image of the mandible bone and the cloud image of the craniomaxillary complex, respectively, to obtain three-dimensional digital images of the mandible and the craniomaxillary complex;

Step S230, using the three-dimensional digital image of the mandible to generate a three-dimensional finite element model of the mandible;

Step S240, using the 3D digital image of the craniomaxillary complex to generate a 3D finite element model of the craniomaxillary complex;

Step S250, combining the three-dimensional finite element model of the mandible and the three-dimensional finite element model of the craniomaxillary complex according to the anatomical structure of the temporomandibular joint to obtain a three-dimensional finite element model of the craniomaxillofacial bone;

Step S260, setting parameters for the three-dimensional finite element model of the craniomaxillofacial bone.

Comparing Fig. 1 and Fig. 2, it can be seen that the embodiment of the present application specifically discloses a method for obtaining three-dimensional digital images of the mandible and the craniomaxillary complex of the test sample.

Optionally, Mimics software can be selected for the process of image screening and three-dimensional reconstruction using the tissue threshold.

Referring to FIG. 3 , FIG. 3 is a flow chart of another method for establishing a craniofacial bone model disclosed in the embodiment of the present application.

As shown in Figure 3, the method includes:

Step S300, obtaining three-dimensional digital images of the mandible and the craniomaxillary complex of the test sample;

A healthy adult volunteer can be selected to have a CT scan of his head, and after processing, a three-dimensional digital image of the mandible and craniomaxillary complex can be obtained.

Step S310, using the three-dimensional digital image of the mandible to generate a three-dimensional finite element model of the mandible;

Step S320, performing surface mesh division on the 3D digital image of the craniomaxillary complex to obtain a facial mesh model of the craniomaxillary complex;

Step S330, combining the three-dimensional finite element model of the mandible and the three-dimensional finite element model of the craniomaxillary complex according to the anatomical structure of the temporomandibular joint to obtain a three-dimensional finite element model of the craniomaxillofacial bone;

Step S340, setting parameters for the three-dimensional finite element model of the craniomaxillofacial bone.

Comparing Figure 1 and Figure 3, it can be seen that when constructing the three-dimensional finite element model of the cranio-maxillary complex, it can be established in the form of surface mesh. Surface meshes take up less computer memory and are faster to compute than volume meshes. The surface mesh can analyze the stress conduction, but it cannot simulate the morphological performance of the bone damage after the impact. However, when the simulated impact test is carried out, after the collision object hits the mandible, the stress is transmitted to the craniomaxillary complex. For the craniomaxillary complex, the stress it bears is greatly reduced, and fractures are not easy to occur, so only stress conduction is performed on it. analysis.

Referring to FIG. 4 , FIG. 4 is a flowchart of another method for establishing a craniofacial bone model disclosed in the embodiment of the present application.

As shown in Figure 4, the method includes:

Step S400, obtaining three-dimensional digital images of the mandible and the craniomaxillary complex of the test sample;

A healthy adult volunteer can be selected to have a CT scan of his head, and after processing, a three-dimensional digital image of the mandible and craniomaxillary complex can be obtained.

Step S410, performing surface mesh division on the three-dimensional digital image of the mandible to obtain a surface mesh model of the mandible;

Step S420, performing surface calculation on the mandibular surface mesh model to obtain a nurbs surface;

Step S430, creating a CAD three-dimensional solid model of the mandible according to the nurbs surface;

Step S440, performing volume grid division on the mandible CAD three-dimensional solid model to obtain a mandible volume grid model;

Step S450, performing surface mesh division on the 3D digital image of the craniomaxillary complex to obtain a facial mesh model of the craniomaxillary complex;

Step S460, according to the anatomical structure of the temporomandibular joint, combine the three-dimensional finite element model of the mandible and the three-dimensional finite element model of the craniomaxillary complex to obtain the three-dimensional finite element model of the craniomaxillofacial bone;

Step S470, setting parameters for the three-dimensional finite element model of the craniomaxillofacial bone.

Optionally, before step S420, the mandibular surface mesh model can also be preprocessed, the deformed mesh can be repaired, and redundant geometric points and surfaces can be eliminated. The model is made more accurate by preprocessing.

Optionally, the nurbs surface obtained in step S420 can be further repaired to repair surface gaps and long and narrow surfaces.

Optionally, the process of steps S420-S430 can be realized by using Geomagic software. As for the process of volume mesh division in step S440, Hypermesh software can be selected for implementation.

In this embodiment, the 3D finite element model of the mandible is constructed in the form of volume mesh. Although the computational complexity of the volume mesh is higher than that of the surface mesh, the volume mesh can simulate the fracture and damage of the mandible after collision. In this case, this is not possible with surface meshes.

Based on the above two embodiments, the present application can choose to establish a mandibular body mesh model and a craniomaxillary complex body mesh model, and combine the two to obtain a craniomaxillofacial bone model. In this way, the built cranio-maxillofacial bone model is closer to the anatomical shape of the real human cranio-maxillofacial face, and can satisfy the impact injury simulation, and the number of meshes of the built model will not be too many, reducing the computational complexity.

Next, in another embodiment of the present application, the process of the above-mentioned step S440 "carrying out volume grid division on the CAD three-dimensional solid model of the mandible to obtain a volume grid model of the mandible" is introduced, as shown in FIG. 5 , the The process includes:

Step S500, determining the boundary contour line of the CAD three-dimensional solid model of the mandible, and performing geometric cleaning;

Through geometric cleaning, the nerve lines on the surface of the model are removed, and the irregular parts of the surface of the model are repaired at the same time.

Step S510, dividing the mandible CAD three-dimensional solid model into blocks according to preset rules;

When the model is divided into blocks, it is generally required that the shape of each part is relatively regular.

Step S520, performing volume mesh division on each block;

In the Hypermesh software, according to the shape and size of each block, select the appropriate panel to divide the surface mesh of each block, and then select the appropriate operation method to form the volume mesh.

Step S530 , combining the divided blocks of the body mesh to obtain the mandible body mesh model.

When combining blocks, it is necessary to ensure the quality of the combined body mesh, such as unit shape, minimum mesh size, model hole position processing, etc., so that there is no deformed body mesh in the final mandibular body mesh model grid.

The craniomaxillofacial bone model building device provided in the embodiment of the present application is described below, and the craniomaxillofacial bone model building device described below and the craniomaxillofacial bone model building method described above can be referred to in correspondence.

Referring to FIG. 6 , FIG. 6 is a schematic structural diagram of a craniomaxillofacial bone model building device disclosed in an embodiment of the present application.

As shown in Figure 6, the device includes:

An image acquisition unit 61, configured to acquire a three-dimensional digital image of the jaw of the test sample and the rest of the craniomaxillofacial bone;

A jaw model generating unit 62, configured to generate a three-dimensional finite element model of the jaw using the three-dimensional digital image of the jaw;

The remaining craniofacial bone model generation unit 63 is used to generate a three-dimensional finite element model of the remaining craniomaxillofacial bone using the three-dimensional digital image of the remaining craniomaxillofacial bone;

The model combination unit 64 is used to combine the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the remaining craniofacial bone according to the anatomical structure of the maxillofacial bone to obtain the three-dimensional finite element model of the craniomaxillofacial bone;

The model parameter setting unit 65 is configured to set the parameters of the three-dimensional finite element model of the cranio-maxillofacial bone, the parameters include the contact type between the jaw and the rest of the cranio-maxillofacial bone, and the boundary conditions of the jaw displacement.

Optionally, in the above-mentioned embodiment of the present application, during the process of establishing the craniofacial bone model, three-dimensional finite element models are respectively established for the jaw bone and the remaining cranio-maxillofacial bone, and then combined. Wherein, the jaw can be a mandible, a maxilla or a collection of maxilla and mandible. For the convenience of explanation, the mandible is taken as an example below, and the corresponding remaining craniomaxillofacial bone is the craniomaxillary complex.

Optionally, as shown in FIG. 7, the image acquisition unit 61 may include:

A CT image acquisition unit 611, configured to acquire a maxillofacial thin-layer CT scan image of the test sample;

An image screening unit 612, configured to filter out mandibular skeleton cloud images and craniomaxillary complex cloud images respectively according to the tissue thresholds of the mandible and craniomaxillary complexes;

The three-dimensional reconstruction unit 613 is configured to perform three-dimensional reconstruction on the cloud image of the mandible bone and the cloud image of the craniomaxillary complex, respectively, to obtain a three-dimensional digital image of the mandible and the cranio-maxillary complex.

Optionally, as shown in FIG. 8, the above-mentioned remaining craniomaxillofacial bone model generating unit 63 may include:

The first remaining craniomaxillofacial bone model generating subunit 631 is configured to divide the three-dimensional digital image of the craniomaxillary complex into a facial mesh to obtain a craniomaxillary complex facial mesh model.

Optionally, as shown in Figure 9, the above-mentioned jaw model generation unit 62 may include:

The first jawbone model generating subunit 621 is configured to perform surface mesh division on the 3D digital image of the mandible to obtain a mandible surface mesh model;

The second jaw model generation subunit 622 is used to perform surface calculation on the mandibular surface mesh model to obtain a nurbs surface;

The third jaw model generation subunit 623 is used to create a mandibular CAD three-dimensional solid model according to the nurbs surface;

The fourth jawbone model generating subunit 624 is configured to perform volume mesh division on the mandible CAD three-dimensional solid model to obtain a mandible volume mesh model.

Optionally, as shown in Figure 10, the fourth jaw model generation subunit 624 may include:

Contour line determination unit 6241, configured to determine the boundary contour line of the mandible CAD three-dimensional solid model, and perform geometric cleaning;

A block processing unit 6242, configured to block the CAD three-dimensional solid model of the mandible according to preset rules;

A volume grid division unit 6243, configured to perform volume grid division on each block;

The block combination unit 6244 is configured to combine the blocks after the volume mesh division to obtain the mandible volume mesh model.

The craniomaxillofacial bone model establishment device provided in the embodiment of the present application uses the three-dimensional digital images of the jaw bone and remaining craniomaxillofacial bone of the test sample to generate a corresponding three-dimensional finite element model of the jaw bone and a three-dimensional finite element model of the remaining craniomaxillofacial bone , and according to the anatomical structure of the maxillofacial bone, combine the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the remaining craniofacial bone to obtain the three-dimensional finite element model of the maxillofacial bone, and finally calculate the three-dimensional finite element model of the maxillofacial bone The parameters of the finite element model are set, such as the contact type between the jaw and the rest of the craniomaxillofacial bone, the boundary conditions of the jaw displacement, etc. Since the three-dimensional finite element model of the maxillofacial bone established by the application includes the jaw and the rest of the craniomaxillofacial bone, which is a complex, including the complete anatomical form of the craniomaxillofacial region, the craniofacial bone established using the device of the present application The three-dimensional finite element model can be used for crash tests under various conditions, and when simulating a crash test, it can not only simulate the complete morphology of the bone damage after the impact of the jaw, but also analyze the stress conduction of the remaining cranial and maxillofacial bones. The simulation is higher and the clinical guidance is stronger.

Finally, it should also be noted that in this text, relational terms such as first and second etc. are only used to distinguish one entity or operation from another, and do not necessarily require or imply that these entities or operations, any such actual relationship or order exists. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the present application will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (8)

1. A craniomaxillofacial bone model building method, is characterized in that, comprises: Obtaining a three-dimensional digital image of the jaw and remaining cranio-maxillofacial bone of the test sample; Using the three-dimensional digital image of the jaw to generate a three-dimensional finite element model of the jaw, and using the three-dimensional digital image of the remaining craniomaxillofacial bone to generate a three-dimensional finite element model of the remaining craniomaxillofacial bone; According to the maxillofacial anatomical structure, combining the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the remaining cranio-maxillofacial bone to obtain the three-dimensional finite element model of the cranio-maxillofacial bone; Setting parameters for the three-dimensional finite element model of the craniomaxillofacial bone, the parameters include the contact type between the jaw and the rest of the craniomaxillofacial bone, and the displacement boundary conditions of the jaw; The jaw bone is the mandible, and the remaining craniomaxillofacial bone is a craniomaxillary complex, and then the three-dimensional digital images of the jaw bone and the remaining craniomaxillofacial bone of the test sample obtained include: Obtain the maxillofacial thin layer CT scan image of the test sample; According to the tissue threshold of the mandible and the craniomaxillary complex, the mandibular bone cloud map and the craniomaxillary complex cloud map were screened out respectively; Three-dimensional reconstruction is performed on the mandibular skeleton cloud image and the craniomaxillary complex cloud image respectively to obtain three-dimensional digital images of the mandible and the cranio-maxillary complex. 2. method according to claim 1, is characterized in that, described utilizing the three-dimensional digital image of remaining craniomaxillofacial bone to generate surplus craniomaxillofacial bone three-dimensional finite element model, comprising: The 3D digital image of the craniomaxillary complex is subjected to face mesh division to obtain a craniomaxillary complex face mesh model. 3. The method according to claim 1, wherein said utilizing the three-dimensional digital image of the jaw to generate a three-dimensional finite element model of the jaw comprises: Performing face mesh division on the three-dimensional digital image of the mandible to obtain a mandible face mesh model; Perform surface calculation on the mandibular surface mesh model to obtain a nurbs surface; Create a mandible CAD three-dimensional solid model according to the nurbs surface; The mandible CAD three-dimensional solid model is divided into volume grids to obtain the mandible volume grid model. 4. method according to claim 3, is characterized in that, described mandibular CAD three-dimensional entity model is carried out body grid division, obtains mandible bone body grid model, comprising: Determining the boundary outline of the mandibular CAD three-dimensional solid model, and performing geometric cleaning; According to preset rules, the CAD three-dimensional solid model of the mandible is divided into blocks; Carry out volume mesh division for each block; Combining the divided blocks of the body mesh to obtain the mandible body mesh model. 5. A craniomaxillofacial bone model building device, characterized in that, comprising: An image acquisition unit, configured to acquire a three-dimensional digital image of the test sample's jaw and remaining craniomaxillofacial bone; A jaw model generating unit, configured to generate a three-dimensional finite element model of the jaw using the three-dimensional digital image of the jaw; A remaining craniomaxillofacial bone model generating unit, configured to generate a three-dimensional finite element model of the remaining craniomaxillofacial bone using the three-dimensional digital image of the remaining craniomaxillofacial bone; A model combination unit, configured to combine the three-dimensional finite element model of the jaw with the three-dimensional finite element model of the rest of the cranio-maxillofacial bone according to the anatomical structure of the maxillofacial bone to obtain the three-dimensional finite element model of the cranio-maxillofacial bone; A model parameter setting unit, configured to set parameters for the three-dimensional finite element model of the craniomaxillofacial bone, the parameters include the contact type between the jaw and the rest of the craniomaxillofacial bone, and the boundary conditions of jaw displacement; The jaw bone is the mandible, and the remaining craniomaxillofacial bone is the craniomaxillary complex, then the image acquisition unit includes: A CT image acquisition unit, configured to acquire a maxillofacial thin-slice CT scan image of a test sample; The image screening unit is used to filter out the mandibular bone cloud map and the craniomaxillary complex cloud map respectively according to the tissue threshold of the mandible and the craniomaxillary complex; The three-dimensional reconstruction unit is used to respectively perform three-dimensional reconstruction on the cloud image of the mandible bone and the cloud image of the craniomaxillary complex to obtain three-dimensional digital images of the mandible and the cranio-maxillary complex. 6. device according to claim 5, is characterized in that, described surplus craniomaxillofacial bone model generation unit comprises: The first remaining craniomaxillofacial bone model generating subunit is used to divide the three-dimensional digital image of the craniomaxillary complex into a facial mesh to obtain a cranial maxillofacial complex facial mesh model. 7. The device according to claim 5, wherein the jaw model generating unit comprises: The first jawbone model generating subunit is used to perform surface mesh division on the three-dimensional digital image of the mandible to obtain a mandible surface mesh model; The second jaw model generation subunit is used to perform surface calculation on the mandibular surface mesh model to obtain a nurbs surface; The third jawbone model generates a subunit, which is used to create a mandible CAD three-dimensional solid model according to the nurbs surface; The fourth jawbone model generating subunit is used for performing volume grid division on the mandible CAD three-dimensional solid model to obtain a mandible volume grid model. 8. The device according to claim 7, wherein the fourth jaw model generating subunit comprises: A contour line determining unit, configured to determine the boundary contour line of the mandible CAD three-dimensional solid model, and perform geometric cleaning; A block processing unit, configured to block the CAD three-dimensional solid model of the mandible according to preset rules; A volume grid division unit, used for volume grid division of each block; The block combination unit is used to combine the blocks after the body mesh is divided to obtain the mandible body mesh model.