CN115919486A - A simplified way to visualize orthodontic treatment goals - Google Patents

Abstract

The invention discloses a method for simplifying a visual orthodontic treatment target, which sequentially comprises the following steps: acquiring a lateral skull film, importing the lateral skull film into image processing software, preprocessing the lateral film to adjust the image position and calibrate scales, drawing an occlusion plane and a selected reference line and carrying out corresponding measurement, determining the vertical and sagittal positions of incisors, determining the transverse target position of the incisors, simply arranging the teeth, and determining whether the transverse adjustment is needed or not, a tooth extraction scheme and an anchorage design according to the tooth arrangement result. The method is based on the thought and the steps for realizing the simplified orthodontic visual treatment target (VTO) by the patient side film and the photo, the consideration of the soft tissue side appearance and the tooth movement limit is taken into the VTO design system for the first time, the steps are simple, the arrangement is clear, the operation time is short, and the method is particularly suitable for scenes such as orthodontic teaching, doctor scheme designation, doctor-patient communication and the like.

Description

A simplified way to visualize orthodontic treatment goals

technical field

The invention belongs to the technical field of orthodontic treatment, and in particular relates to a method for simplifying and visualizing positive treatment targets.

Background technique

Malocclusion is one of the three major oral diseases identified by the World Health Organization (WHO). Among them, the convex malocclusion with the main complaint of "convex mouth" is the most common type of dental and maxillofacial deformity in clinical practice, accounting for more than 49% of orthodontic patients. The personalized orthodontic treatment plan and the final treatment effect depend on the initial three-dimensional position and movement limit of the patient's teeth in the jawbone, as well as the relationship between the amount of tooth movement and soft tissue changes. A set of visual treatment target formulation system and tooth arrangement plan will provide important assistance for orthodontists to formulate treatment goals and clarify treatment methods.

The traditional visual treatment objective (VTO) prediction of VTO refers to predicting and simulating the results of orthodontic treatment based on the patient's initial dental and maxillofacial conditions through cephalometric and model analysis methods. Since 1957, different scholars have proposed different VTO methods, among which the Ricketts VTO method is currently more commonly used. In this method, the lower incisors were positioned first, and the position of the incisal margin of the lower incisors was set at 1 mm in front of the AP line, and then the positions of the upper incisors and posterior teeth were determined according to the position of the lower incisors. Growth and development are also included.

Traditional diagnostic tooth arrangement needs to take impressions and fill plaster models. The steps are as follows: 1. Preliminarily determine the arch shape of the dental arch, whether tooth extraction is required and how to apply it according to the model measurement, diagnostic design and X-ray positioning lateral film visual treatment target (VTO) prediction. The number of teeth extracted and the position of the teeth; 2. Separate the dentition that needs to be rearranged; 3. Use 2 self-made ligature wires with a diameter of 0.2 mm twisted into twisted wires instead of wire saws, and each gypsum tooth that needs to be rearranged After sawing to the adjacent point, break it apart, so that the adjacency of the gypsum teeth is not damaged as much as possible; 4. Trim the shape of each gypsum tooth and root after sawing, and rearrange each gypsum tooth on the model according to the ideal bow shape. According to VTO prediction and model measurement, the position of maxillary incisors and the distance between maxillary canines were determined first, and then other teeth were arranged. It is required that the gypsum teeth be in close contact and arranged neatly. The inclination, height, shape of the dental arch, and the relationship between the upper and lower dental arches of the gypsum teeth must be correct.

Digital VTO and digital teeth arrangement, with the rapid development of computer technology, digital teeth arrangement and digital VTO technology were born, and can be used for the changes of dentition and bite, teeth and jaw, lip position and craniofacial relationship in orthodontic treatment. simulation. At present, the full-mouth orthodontic system including invisible orthodontic technology and digital labial-lingual orthodontic technology can realize VTO for the final orthodontic result of dentition and occlusion through digital tooth arrangement and simulated crown movement.

Traditional VTO drawing requires a lot of paper and pen tracing and manual calculations. The procedure is complicated, the technique is highly sensitive, and the operation time is long. Only some orthodontic specialists use it in complex cases, and it is difficult for orthodontic students and doctors to master it. The generalization is not strong, and the traditional VTO is mostly predicted in the lateral cranial view, that is, the sagittal direction, and the central incisors and first molars are mostly displayed, and the diagnostic tooth arrangement in other directions is not included in the VTO system. It reflects the movement target position of teeth other than central incisors and first molars, and cannot provide specific tooth extraction plans and anchorage design references. At the same time, the traditional VTO results are less vivid and difficult for patients to understand.

Traditional diagnostic tooth arrangement experiments need to make corresponding models, dentition cutting, etc. The steps are cumbersome, and it is impossible to accurately arrange teeth according to the VTO target position. Digital VTO and digital tooth arrangement are mostly based on digital impressions, which require corresponding oral scanning instruments or Model scanning equipment has high economic cost barriers. At present, the treatment design of non-invisible and personalized lip-lingual patients has no conditions for routine digital VTO and tooth arrangement.

Contents of the invention

In view of the problems existing in the prior art, the purpose of the design of the present invention is to provide a method for simplifying and visualizing orthodontic treatment targets, simplifying operation steps and operation time, and reducing economic costs for both doctors and patients.

The present invention is specifically realized through the following technical solutions:

A method for simplifying the visualization of orthodontic treatment goals comprising the steps of:

1) Take a cephalometric film, or intercept a cephalometric film by CBCT, and import the cephalometric film into image processing software, such as Powerpoint, Keynote, geometric sketchpad and other software;

2) Lateral film preprocessing: According to the selected reference plane and reference line requirements, adjust the lateral film by rotating, zooming, etc., such as adjusting the picture with the orbito-ear plane, anterior skull Scale calibration is carried out on the scale on the lateral view obtained after processing with the scale/Dolphin and other CT 3D reconstruction software when the lateral view is taken. The specific steps: the scale on the original lateral view can be directly used as the measuring ruler by copying and cutting, or scaled at a certain ratio In the lateral view, the measurement distance in the subsequent steps is converted by the corresponding ratio between the length of the line segment and the scale of the scale. If the software function conditions permit, the actual distance of the scale can be defined, and then the subsequent measurement can be directly carried out;

3) Adjust and cover the upper and lower incisor pictures according to the size of the teeth with the same name on the lateral view, or select the software that can recognize the shape of the upper and lower incisors and automatically cut them out to realize the tooth movement.

4) Draw the occlusal plane and the reference lines required to determine the treatment target position of the upper and lower incisors, and perform corresponding measurements. Due to the different orthodontic concepts, the reference line and the corresponding reference plane in this step can be determined by the user. For example, the aesthetic plane proposed by Ricketts - E line, the GVL line (Glabella Vertical Line) proposed by Andrews, and the GVL line proposed by Arnett TVL line (SubnasaleTrueVertical Line, the vertical line under the nose point in the natural head position), S line proposed by Steiner, T line proposed by Schwarz, H line proposed by Holdaway, zero meridian, etc. The involved occlusal plane can be determined according to the selected system and choose the functional maxillary plane or anatomical maxillary plane;

For example, select the E-line of the aesthetic plane, and after processing the lateral view with the orbital-ear plane horizontal reference line in 2), draw the functional maxillary plane in this step; then draw the E-line to measure the distance from the upper and lower lips to the E-line respectively, and denote it as dUE, dLE;

5) Determine the vertical position of the incisor;

6) Determine the sagittal position of the incisor;

7) Determine the target position of the incisors laterally (near-distal direction) according to the upper and lower midlines;

8) Determine the target position of the incisor treatment;

9) Simple tooth arrangement and tooth extraction plan and anchorage design are determined according to the result of tooth arrangement.

Further, step 5) the vertical position of the central incisors includes the vertical position of the upper incisors and the vertical position of the lower incisors. The position is based on the normal overjaw, and the incisor of the upper incisor is located at 1/3 of the crown of the lower incisor.

Further, if the actual vertical movement of the upper incisor exceeds 4mm, adjust the target position to 4mm to depress or elongate the limit of the anterior teeth.

Further, the specific steps for determining the sagittal position of the incisor in step 6) are:

a) According to the distance from the lower lip to the E line, the sagittal position of the upper incisors is determined by calculating the proportional relationship between the adduction of the lips and the adduction of the upper incisors, and the ideal sagittal position of the upper incisors is set;

b) Simulate the row of upper incisors, adjust the position of the upper incisors parallel to the occlusal plane, adjust the torque, and place the root between the alveolar bones to prevent the root from breaking through the posterior boundary of the palatal bone plate, so as to meet the health of the root bone, and pay attention Incising guide slope, judging whether the target position of upper incisor movement exceeds the limit of tooth movement, if the simulated tooth arrangement cannot meet the conditions, appropriately compromise the sagittal direction to the target position;

c) Simulated row of lower incisors: adjust the position of the lower incisors to form a normal coverage, the root of the tooth stands in the center of the lower alveolar bone, and judge whether the tooth movement limit is exceeded. If the conditions cannot be met, the target position of the upper and lower incisors will be compromised again.

Further, determining the lateral target position of the incisors in step 7) specifically includes determining the upper and lower midlines according to the clinical examination combined with clinical data, and further determining the lateral movement of the upper and lower central incisors.

Further, clinical examination combined with clinical data is the patient's frontal smile image, model or CBCT.

Further, determining the treatment target position of the incisors in step 8) includes: determining the final target position of the upper incisors, recording the sagittal, vertical and lateral movement amounts; determining the final target position of the lower incisors, recording the sagittal, vertical and lateral movement amounts; Amount of lateral movement.

Further, the specific steps of simple teeth arrangement in step 9) are:

a) Open the photo of the upper and lower occlusal surfaces of the patient, adjust the mirror image of the picture if necessary to make it conform to the situation in the mouth, and transfer the scale;

b) Scale transfer: use method 1 or method 2 for scale transfer,

Method 1 is specifically: measure the length of the upper and lower first molars with a ruler on the lateral view, transfer the ruler to the oral photograph, or directly transfer the first molar data provided by the model, and adjust the rulers corresponding to the length of the first molars respectively, so that The upper and lower occlusal images share the ruler;

The second method is specifically: transfer the upper and lower occlusal images to the lateral film, adjust the direction of the photo, and adjust the size of the occlusal image by corresponding the incisors, first molars, and second molars on the lateral film and the occlusal image. , so that they share the lateral view scale;

c) Overlay the tooth image material on the upper and lower occlusal images processed in the previous step. The upper and lower teeth are based on the overlap of the edge ridge width. If necessary, the transparency of the tooth material can be adjusted to make this step more efficient, or the tooth shape can be recognized Each tooth is automatically cut out to realize the software processing step of tooth movement;

d) Simulated arrangement of upper and lower incisors: move the incisors to the simulated target position according to the lost shape of the upper and lower incisors and the horizontal target position;

e) Personalized bow shape for the target position: draw the upper and lower occlusal lines similar to the initial bow shape, and select the corresponding standardized bow shape material according to the initial bow shape, such as pointed circle, oval shape, and square circle shape, and make further adjustments; according to the mandible The position of the teeth and the shape of the alveolar bone determine the personalized arch of the mandibular target position, and the upper jaw determines the personalized arch of the maxillary target position according to the occlusal line to match the mandible;

f) The remaining teeth simulate tooth arrangement: the remaining teeth are based on the alveolar bone, and the upper and lower teeth are based on the target arch, that is, the line connecting the buccal cusp of the mandibular teeth is located on the elliptical line as much as possible, and the line connecting the maxillary fossa is located on the ellipse On the shaped line, move the row of teeth along the line of the edge crest.

g) Record the lateral and sagittal movement distances of the upper and lower first molars.

Compared with the prior art, the present invention has the following beneficial effects:

1) The method of the present invention uses the profile soft tissue as the guide to formulate the target position of the upper and lower anterior teeth, which meets the requirements of the current patient's face-to-face type, and at the same time takes into account the health of the root bone and the limit of tooth movement, and conforms to the guidance of healthy orthodontics;

2) In the method of the present invention, for the first time, the step of simulating the VTO in the three-dimensional direction is combined with the VTO and the occlusal image for the first time. At the same time, after simulating tooth arrangement, it has a visual guidance effect on the selection of tooth extraction scheme and the judgment of anchorage control;

3) The steps are simple, well-organized, and the operation time is short, which is especially suitable for orthodontic teaching, doctor plan formulation, and doctor-patient communication;

4) The method of the present invention involves software such as cranial radiographs, extra-oral and intra-oral photos, and PowerPoint as the most common tools. Compared with digital VTO and digital tooth arrangement, the economic cost for both doctors and patients is extremely low, and the promotion is strong.

Description of drawings

Figure 1 is the adjusted lateral cephalogram with the orbito-auricular plane as the horizontal reference line;

Figure 2 is the lateral view after the upper and lower incisor image materials are adjusted according to the size of the lateral view and covered;

Figure 3 is the functional maxillary plane and E-line drawn on the lateral radiograph;

Figure 4 is a diagram for determining the vertical position of the incisors;

Figure 5 is a diagram for determining the ideal position of the upper incisor in the sagittal direction;

Figure 6-7 is a process diagram of determining the actual target position of the upper incisor;

Fig. 8 is a figure for determining the actual target position of the simulated upper and lower incisors;

Figure 9 is the first method for adjusting the shared scale of the upper and lower occlusal images;

Figure 10-12 is the second method for adjusting the shared scale of the upper and lower occlusal images;

Figure 13-14 is a schematic diagram of superimposing the tooth image material on the upper and lower occlusal images;

Figure 15 is a simulation of the upper and lower incisor target teeth arrangement on the upper and lower occlusal images;

Figure 16 is the individualized arch for drawing the occlusal line to simulate the target position of the upper and lower jaws;

Figure 17 is the final occlusal image tooth arrangement diagram.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings in order to better understand the technical solution.

The object of the present invention is an orthodontist, a medical student or a beginner in orthodontics, and the analysis object is an orthodontic masking treatment patient, and a patient with a shortened upper lip or a patient with an abnormal width is an analysis object to be excluded.

The method for simplifying and visualizing the orthodontic treatment target of the present invention is specifically implemented according to the following steps:

Step 1: Take a lateral cephalogram, or obtain a lateral cephalogram by CBCT through three-dimensional software processing, and import the lateral cephalogram into the image processing software. Here, the keynote software is used as an example to adjust the image with the orbital-ear plane as the horizontal reference line. The adjusted lateral cephalometric film was calibrated according to the scale attached to the lateral film obtained after three-dimensional reconstruction of CT software such as scale/Dolphin at the time of shooting, as shown in Figure 1.

Step 2: Adjust and overlay the upper and lower incisor image materials according to the size of the lateral view, as shown in Figure 2.

Step 3: First draw the functional maxillary plane on the lateral cephalogram of step 2, and then draw the E-line, measure the distance from the upper and lower lips to the E-line, and record them as dUE and dLE. As a measuring ruler, the scale can also be converted by the length of the line segment and the scale of the scale, as shown in Figure 3.

Step 4: Determine the vertical position of the incisors so that the incisors of the upper incisors are located 2-4mm below the lower edge of the upper lip. If the actual vertical movement exceeds 4mm, then depress/extend the limit of the anterior teeth to adjust the target position to 4mm, and the lower incisors are vertical The normal overjaw position is used as the standard, and the incisor of the upper incisor is located at 1/3 of the crown of the lower incisor, as shown in Figure 4.

Step 5: Determine the sagittal position of the incisors. According to the distance from the lower lip to the E line, determine the sagittal position of the upper incisors by calculating the proportional relationship between the retraction of the lips and the retraction of the upper incisors, and set the ideal sagittal position of the upper incisors. Depending on race, lip thickness, etc., the reference standard is different. Here, the relationship between upper incisor adduction and lower lip adduction is 1:1 as an example. Under normal circumstances, the lower lip is located slightly behind the E-line. As shown in Figure 5, the distance from the patient’s lower lip to the E-line is 11mm, so about 12mm of retraction of the upper anterior teeth is required to reduce coverage.

Step 6: Simulate the row of upper incisors, adjust the position of the upper incisors parallel to the occlusal plane, adjust the torque, and place the roots between the alveolar bones, as shown in Figure 6, to prevent the roots from breaking through the posterior boundary of the palatal bone plate. It is in line with the health of the root bone, and pay attention to the incisive guide slope to determine whether the upper incisor movement target position exceeds the tooth movement limit. If the simulated tooth arrangement cannot meet the conditions, a proper compromise is made to the sagittal target position, as shown in Figure 7. Simulate the row of lower incisors, adjust the position of the lower incisors to form a normal coverage, the root of the tooth stands in the center of the lower alveolar bone, and judge whether the movement limit of the teeth is exceeded. If the conditions cannot be met, compromise again on the target position of the upper and lower incisors, as shown in Figure 8. The upper anterior teeth retracted 9mm, and the lower anterior teeth retracted 5mm.

Step 7: Determine the lateral target position of the incisors, and determine the lateral movement of the upper and lower central incisors according to the clinical examination and clinical data.

Step 8: Determine the treatment target position of the incisor, respectively determine the final target position of the upper incisor and the lower incisor, and record the sagittal, vertical and lateral movement.

Step 9: Simple teeth arrangement, open the photo of the upper and lower occlusal surfaces of the patient, adjust the mirror image of the image to make it conform to the situation in the mouth, and transfer the scale, using method 1 or method 2 to transfer the scale: method 1 is specifically: use the scale on the lateral view to measure the upper and lower third 1. Molar length, transfer this scale to the oral photo, or directly transfer the first molar data provided by the model, and adjust the scale corresponding to the length of the first molar, so that the upper and lower occlusal images share the scale, as shown in Figure 9;

The second method is specifically: transfer the upper and lower occlusal images to the lateral film, adjust the direction of the photo, and adjust the size of the occlusal image by corresponding the incisors, first molars, and second molars on the lateral film and the occlusal image one by one. Make it share the lateral view ruler, as shown in Figure 10-12;

Overlay the tooth picture material on the original picture, and the upper and lower teeth shall be based on the overlap of the edge ridge width, as shown in Figure 13. In this example, adjust the transparency of the original material to 60% to facilitate the overlapping and subsequent steps, as shown in Figure 14 ;Simulated arrangement of upper and lower incisors: move the incisors to the simulated target position according to the lost shape of the upper and lower incisors, and move the incisors to the simulated target position, as shown in Figure 15; develop a personalized arch at the target position: draw the upper and lower occlusal lines similar to the initial arch, According to the position of the mandibular teeth and the shape of the alveolar bone, the personalized arch shape of the mandibular target position is determined, and the personalized arch shape of the upper jaw target position is determined according to the occlusal line of the upper jaw, so that it matches the mandible, as shown in Figure 16; the rest of the teeth are simulated and arranged Teeth: The rest of the teeth are based on the alveolar bone, and the upper and lower teeth are based on the target arch, that is, the line connecting the buccal cusps of the mandibular teeth is located on the oval line as much as possible, and the line connecting the maxillary fossa is located on the oval line. The ridge line moves along the row of teeth, as shown in Figure 17, and the lateral and sagittal movement distances of the upper and lower first molars are recorded.

Step 10: According to the results of the simulated tooth arrangement, determine the tooth extraction plan according to the orthodontic principle, and determine whether there is any lateral misalignment and its treatment plan (such as maxillary arch expansion, tooth compensation treatment, etc.) according to the horizontal movement distance of the initial molars and target molars ), according to the sagittal movement distance of initial molars and target molars, determine the corresponding anchorage requirements and control plan.

Due to different orthodontic concepts and reference lines in the formulation of the target position of the upper and lower anterior teeth in the present invention, the lateral view in step 1 2) can be adjusted, and the reference line involved in 1 4) (the example of this scheme is E line) can be replaced For other reference lines and corresponding reference planes, such as the GVL line proposed by Andrews, the TVL natural head vertical line proposed by Arnett, the S line proposed by Steiner, the T line proposed by Schwarz, the H line proposed by Holdaway, and the zero meridian. The occlusal plane involved can be determined according to the selected system to select the functional maxillary plane or anatomical maxillary plane.

The corresponding proportional relationship between profile soft tissue and anterior teeth changes can be updated due to data such as race, sample size, and research quality.

The software involved in the present invention can be replaced by other picture processing tools with corresponding functions, such as geometric drawing board and automatic picture cutting software.

The simulated tooth arrangement involved in the present invention can be carried out directly in the corresponding digital tooth arrangement software if conditions permit, and the ideas are basically the same.

Claims (10)

1. A method for simplifying visualization of orthodontic treatment goals, the method comprising the steps of:

1) Shooting a lateral skull film, or intercepting the lateral skull film by CBCT (cone beam computed tomography), and introducing the lateral skull film into image processing software;

2) Side piece pretreatment: adjusting the side film by rotating, zooming and the like according to the selected reference plane and the reference line; calibrating the scales according to the scales carried by the side film obtained after the side film is processed by the scale-carrying/three-dimensional reconstruction software;

3) Adjusting and covering the upper incisor picture and the lower incisor picture according to the size of the same-name teeth on the lateral sheet, or selecting software capable of identifying the upper incisor form and the lower incisor form to automatically perform sectional drawing processing so as to realize tooth movement;

4) Drawing an occlusion plane, determining a reference line required by the upper incisor treatment target position and the lower incisor treatment target position, and performing corresponding required measurement;

5) Determining the vertical position of incisors;

6) Determining the sagittal position of the incisors;

7) Determining the horizontal direction of the incisors, namely the target position in the mesial-distal direction according to the upper and lower middle lines;

8) Determining an incisor treatment target position;

9) And (4) simply arranging teeth, and determining a tooth extraction scheme and an anchorage design according to a tooth arrangement result.

2. The method for simplifying the visualization of the orthodontic treatment target according to claim 1, wherein the calibration of the scale in the step 2) is performed by copying and cutting the scale on the lateral site directly as a measuring scale or scaling the lateral site at a certain ratio, and the distance measured in the subsequent step is converted by the corresponding ratio of the length of the line segment to the scale.

3. The method of claim 1, wherein the reference lines and corresponding reference planes in step 4) are user-defined and include but are not limited to aesthetic planes E lines proposed by Ricketts, GVL lines proposed by Andrews, TVL lines proposed by Arnett, S lines proposed by Steiner, T lines proposed by Schwarz, H lines proposed by Holdaway, zero meridian lines, and wherein the occlusal planes may be selected to be functional or anatomical jaw planes according to the selected system.

4. The method for simplifying visualization of orthodontic treatment objects of claim 1 wherein the vertical incisor positions in step 5) include an upper incisor position and a lower incisor position, the upper incisor position being with the upper incisor tip positioned 2-4mm below the inferior border of the upper lip, the lower incisor position being with respect to the normal overbite, and the upper incisor tip positioned 1/3 of the lower crown.

5. A method for simplifying the visualization of the orthodontic treatment target of claim 3 wherein if the upper incisor is actually moved vertically more than 4mm, the target position is adjusted to 4mm to depress or elongate the anterior limit.

6. A method for simplifying visualization of orthodontic treatment objectives according to claim 1, wherein the step of determining the sagittal location of the incisors in step 6) comprises the specific steps of:

a) Setting an ideal upper incisor vector position according to the selected reference line and the standard;

b) Simulating upper incisors, adjusting the positions of the upper incisors according to the occlusion plane in parallel, adjusting torque, standing tooth roots between alveolar bones, avoiding the tooth roots from breaking through the rear boundary of a palatine side bone plate so as to be in line with the health of the root bones, paying attention to incisal guidance inclination, judging whether the moving target position of the upper incisors exceeds the moving limit of the teeth or not, and properly compromising the sagittal target position if the simulated upper incisors cannot meet the conditions;

c) Simulating lower incisors: and adjusting the position of the lower incisor to form normal coverage, standing the tooth root in the center of the lower alveolar bone, judging whether the tooth movement limit is exceeded, and if the condition cannot be met, re-compromising the target positions of the upper incisor and the lower incisor.

7. The method for simplifying visualization of orthodontic treatment target according to claim 1, wherein the determination of the lateral target site of the incisors in step 7) is further characterized by determining the lateral movement of the upper and lower central incisors by determining the upper and lower central lines according to clinical examination and clinical data.

8. A method for simplifying the visualization of orthodontic treatment goals of claim 7, wherein the clinical examination in combination with the clinical data is a frontal smile image, a model or CBCT of the patient.

9. The method for simplifying visualization of orthodontic treatment target according to claim 1, wherein the determining of the incisor treatment target site in the step 8) comprises: determining the final target position of the upper incisor and recording the sagittal, vertical and transverse movement amounts; and determining the final target position of the lower incisor, and recording the sagittal, vertical and transverse movement amounts.

10. The method for simplifying visualization of orthodontic treatment objects of claim 1, wherein the step 9) of simply arranging teeth comprises the specific steps of:

a) Opening the picture of the upper occlusal surface and the lower occlusal surface of the patient, adjusting the mirror image of the picture to meet the intraoral condition if necessary, and transferring a ruler;

b) Scale transfer: the scale transfer is carried out by adopting the method one or the method two,

the first method specifically comprises the following steps: measuring the lengths of upper and lower first molars by using a ruler on the side position sheet, transferring the ruler into a mouth image photo, or directly providing first molars data by the model for transferring, and respectively adjusting the ruler corresponding to the lengths of the first molars to enable the upper and lower occlusal images to share the ruler;

the second method specifically comprises the following steps: respectively transferring the upper occlusion image and the lower occlusion image to a lateral plate, adjusting the direction of the picture, and corresponding the incisors, the first molars and the second molars on the lateral plate and the occlusion image to one-to-one correspondence to adjust the size of the occlusion image so that the occlusion images share a lateral plate scale;

c) Overlapping the tooth picture material on the upper and lower occlusion pictures processed in the previous step, wherein the upper and lower jaw teeth are subject to edge ridge width overlapping, or automatically performing matting processing on each tooth by selecting recognizable tooth forms to realize the software processing of tooth movement;

d) Simulating tooth arrangement by upper and lower incisors: moving the incisors to the simulated target position according to the upper and lower incisor disordering direction and the transverse target position;

e) And (3) establishing a target position personalized arch: drawing up and down occlusal lines similar to the initial arch, determining the personalized arch of the lower jaw target position according to the positions of lower jaw teeth and the shape of alveolar bones, and determining the personalized arch of the upper jaw target position according to the occlusal lines by the upper jaw to enable the upper jaw target position to be matched with the lower jaw;

f) Simulating tooth arrangement by other teeth: taking alveolar bone as a reference for other teeth, taking arch shapes of upper and lower jaw teeth as a basis of a target position, namely, a connecting line of cheek tips of lower jaw is positioned on an elliptic line as much as possible, a connecting line of a central fossa of upper jaw is positioned on the elliptic line, and arranging teeth according to a marginal ridge connecting line;

g) The lateral and sagittal movement distances of the upper and lower first molars were recorded.

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