CN117017531A

CN117017531A - Personalized craniofacial growth guide, design method thereof and craniofacial growth guide system

Info

Publication number: CN117017531A
Application number: CN202311062297.XA
Authority: CN
Inventors: 郑旭; 张磊; 张佳超
Original assignee: Romo Technology Beijing Co ltd
Current assignee: Romo Technology Beijing Co ltd
Priority date: 2023-08-22
Filing date: 2023-08-22
Publication date: 2023-11-10

Abstract

The application provides a personalized craniofacial growth guide, a design method thereof and a craniofacial growth guide system, wherein the design method comprises the following steps: acquiring an initial value of a craniofacial parameter combination of a guiding object; determining a target value of a craniofacial parameter combination of the guidance object; determining design parameters of the basic structural units of the personalized craniofacial growth guide based on the target values; opening occlusion of the guiding object based on the target value on the closed frame, and designing a personalized craniofacial growth guide based on the design parameters. According to the technical scheme, the structure of the personalized growth guide is designed according to the physiological characteristics of human craniofacial growth and development at different periods and aiming at the characteristics of personalized tooth surface deformity of a guided subject, so that the optimal balance of personalized morphology and functions of each part of the craniofacial of the guided subject is realized.

Description

Personalized craniofacial growth guide, design method thereof and craniofacial growth guide system

Technical Field

The application belongs to the technical field of craniofacial orthodontics, and particularly provides a personalized craniofacial growth guide, a design method thereof and a craniofacial growth guide system.

Background

The craniofacial region can be divided into three parts, namely teeth, occlusion, bones and soft tissues, which respectively follow different growth and development rules in the growth and development process and interact with each other. In the growth and development process of human being, under the influence of genetic or environmental factors, the development of teeth, occlusion, bones and soft tissues may generate such problems, and respectively generate mismatching deformity, jawbone dysplasia and soft tissue dysplasia, which are collectively called dentofacial deformity, and threaten the beauty, function and health of human being, so that the dentofacial deformity which is generated in the growth and development process is corrected by a plurality of treatment devices, the possible problems in the subsequent development process are prevented, and the method is a common method for carrying out preventive correction and blocking correction on the dentofacial deformity in the field of orthodontic.

The use of growth potential to guide the growth of teeth, jawbone and soft tissue in the ideal direction is an important concept for early intervention of tooth surface deformity, and various devices with different materials and patterns, such as occlusion inducers, functional appliances, muscle trainers, jaw position adjusters and the like, which are made of materials such as metal, resin, plastic, silica gel and the like and are in fixed/removable, integrated/split, prefabricated/customized and the like, are adopted. The basic common point of the above devices is to set and maintain the target site of the teeth or jawbone, change the spatial layout of the orofacial tissue structure and the biomechanical environment (the magnitude, direction, action site of the forces generated by the oral function), utilize the growth potential to assist the growth of the teeth or jawbone to the target site, so they can be collectively referred to as craniofacial growth guide devices.

The various existing craniofacial growth guiding devices are generally designed aiming at solving the specific problem of a certain tissue structure, and the different requirements of different tissue structure forms and functions of the face are not comprehensively considered in the design concept, so that the device has some limitations in the aspects of indication selection and curative effect; meanwhile, the design concept of the growth guiding device is lacking, so that the final set target position is rough and personalized, the specific treatment requirements of different patients cannot be met, the curative effect is influenced, the treatment course is prolonged, the comfort level is influenced, and the matching difficulty of the patients is increased.

Disclosure of Invention

The application aims to solve the problems in the prior art, and provides a personalized craniofacial growth guide and a design method thereof based on a reasonable medical concept and conforming to physiological characteristics of each tissue structure of the craniofacial during different growth periods, and a craniofacial growth guide system formed by the personalized craniofacial growth guide.

A first aspect of the present application provides a method of designing a personalized craniofacial growth guide, the method comprising the steps of:

acquiring an initial value of a craniofacial parameter combination of a guiding object;

Determining a target value of a craniofacial parameter combination of the guidance object;

determining design parameters of the basic structural units of the personalized craniofacial growth guide based on the target values;

opening occlusion of the guiding object based on the target value on the closed frame, and designing a personalized craniofacial growth guide based on the design parameters.

Further, the craniofacial parameter combination includes: a set of dental surface characteristic parameters and/or a dental arch morphology of the subject is guided.

Further, the dental face feature parameter set includes: facial features of the guided object in the vertical and sagittal directions and dental features of the guided object in the sagittal direction.

Preferably, the dental face feature parameter set further includes: bone-type, tooth-type features of the guiding object in the vertical direction, bone-type features of the guiding object in the sagittal direction, and facial-type, bone-type and tooth-type features of the guiding object in the horizontal direction.

Further, an initial value of the dental arch morphology is characterized by an initial dental arch curve, and a target value of the dental arch morphology is characterized by a target dental arch curve.

Further, the target dental arch curve is generated by:

marking the tooth characteristic points of the guiding object;

measuring the first characteristic parameters C of the guide object ₁ First, theTwo characteristic parameters C ₂ ；

Based on the first characteristic parameter C ₁ Determination of a first ideal dental arch characteristic R ₁ According to R ₁ Determining a first curve of the form:

Y＝AX ⁴ +BX ² ，

wherein X, Y is the coordinates of each point on the curve and X, Y is on the jaw plane, the X axis and Y axis are orthogonal, the Y axis corresponds to the projection of the median sagittal plane on the jaw plane, A, B is the coefficients of the fourth term and the second term of the first curve and is perpendicular to the R ₁ Coupling correlation;

based on the second characteristic parameter C ₂ Determination of a second ideal dental arch characteristic R ₂ According to R ₂ Determining a second curve of the form:

and splicing the part of the first curve in the first dentition interval and the part of the second curve in the second dentition interval to obtain the target dental arch curve of the guiding object in one craniofacial growth guiding period.

Preferably, the C ₁ 、C ₂ The same craniofacial growth guiding period of the guiding object is kept unchanged, and ₁ 、C ₂ different craniofacial growth guide periods of the guide object have different defining modes;

the R is ₁ 、R ₂ Ideal arch for characterizing the dental jaw of a guided subject, and R ₁ 、R ₂ Respectively with the C ₁ 、C ₂ The strong correlation is counted.

Preferably, the first dentition interval is left and right posterior dentition; and, the second dentition interval is an anterior dentition interval.

Preferably, the junction point of the first dentition interval and the second dentition interval is positioned in the projection area of the cuspids on the jaw plane.

Further, the basic structural unit includes: upper guide sprouting groove, lower guide sprouting groove and plywood for connecting upper guide sprouting groove and lower guide sprouting groove.

Preferably, the design parameters include: the shape, style, angle and depth of the upper guide sprouting groove and the lower guide sprouting groove.

Preferably, the craniofacial parameter combination further comprises a morphology of each tooth of the lead subject.

Preferably, the design method further comprises the steps of: adding at least one retention attachment to the personalized craniofacial growth guide, the retention attachment being designed to retain the craniofacial growth guide on deciduous teeth where root development is substantially complete or deciduous teeth where root absorption does not exceed 1/2 of root length.

Preferably, the design method further comprises the steps of: at least one guide accessory is added to the personalized craniofacial growth guide, wherein the guide accessory enables teeth which are erupting or are about to erupt to an ideal direction and position.

Preferably, the craniofacial parameter combination further comprises guiding the functional status of the masticatory organ of the subject.

Preferably, the design method further comprises the steps of: at least one of a lip shield, a tongue shield, a cheek shield and a tongue position guide is added into the personalized craniofacial growth guide.

A second aspect of the present application provides a personalized craniofacial growth guide comprised of a plurality of basic structural units including an upper guide germination slot, a lower guide germination slot, and a plywood connecting the upper and lower guide germination slots;

the personalized craniofacial growth guide is designed and generated by the design method of the personalized craniofacial growth guide.

A third aspect of the application provides a craniofacial growth guidance system comprising at least two of the aforementioned personalized craniofacial growth guides for guiding a craniofacial growth procedure of a guidance object in at least two mutually non-overlapping craniofacial growth guidance cycles, respectively.

According to the technical scheme provided by the embodiment of the application, the physiological characteristics of different periods of human craniofacial growth and development are complied, the spatial position relation and biomechanical environment between different tissue structures of the craniofacial are changed in stages according to the personalized tooth surface deformity characteristics of the guiding objects, meanwhile, based on a reasonable medical concept, the chewing organ is considered as a complete functional unit, the functional principle and the aesthetic principle of the chewing organ are respected, and the optimal balance of the personalized form and the personalized function of each guiding object chewing organ is realized.

Drawings

FIG. 1a is a schematic diagram of a personalized craniofacial growth guide provided in accordance with an embodiment of the present application;

FIG. 1b is a top view of a personalized craniofacial growth guide provided in accordance with an embodiment of the present application;

FIG. 1c is a side view of a personalized craniofacial growth guide provided in accordance with an embodiment of the present application;

FIG. 1d is a rear view of a personalized craniofacial growth guide provided in accordance with an embodiment of the present application;

FIG. 2 is a flow chart of a method of designing a personalized craniofacial growth guide provided in accordance with an embodiment of the present application;

FIG. 3a is an image of various angles of the craniofacial region of a guided subject prior to the beginning of a craniofacial growth guidance cycle in one particular embodiment;

FIG. 3b is a photograph of angles of the interior of the oral cavity of a subject prior to the initiation of a craniofacial growth initiation cycle, in one embodiment;

fig. 3c shows an embodiment of an oral X-ray Qu Duanpian of a subject before a craniofacial growth initiation of a guidance cycle;

FIG. 3d is a craniofacial azimuthal X-ray of a subject before a craniofacial growth initiation of a guidance cycle in one embodiment;

FIG. 3e is a craniofacial forward X-ray film of a subject prior to the beginning of a craniofacial growth initiation cycle;

FIG. 4 is a flow chart of determining a set of facial feature parameters according to an embodiment of the present application;

FIG. 5 is a relative positional relationship of a three-dimensional solid model of the dental jaw in a target state on a mechanical jig according to an embodiment of the application;

FIG. 6 is a flow chart of determining a target arch curve of a guided subject over a craniofacial growth guide cycle in accordance with an embodiment of the present application;

FIG. 7 is a specific dental chart;

FIG. 8 is a graph showing the result of fitting a real dental jaw that meets the ideal arching criterion using a 4-degree function;

fig. 9 is a view of the bite of a tooth of a subject after the subject has used the craniofacial growth guide system provided by an embodiment of the present application.

Detailed Description

The present application will be further described below based on preferred embodiments with reference to the accompanying drawings.

Fig. 1a is a schematic structural view of a personalized craniofacial growth guide 8 according to some preferred embodiments of the present application, and fig. 1 b-1 d are top, side, and back views, respectively, of the personalized craniofacial growth guide 8.

The personalized craniofacial growth guide 8 is for guiding the growth of the craniofacial face of a guided subject during a craniofacial growth guide cycle thereof, wherein in an embodiment of the application the guided subject is a teenager or child whose teeth and bite, skull and jaw, facial soft tissue are at least partially in a growing stage.

Further, guiding the craniofacial growth of the guided subject can refer to blocking and correcting the dental surface deformity problems, such as the mismatching deformity, jawbone dysplasia, soft tissue dysplasia and the like, of each part in the growth and development process by combining external intervention (including changing the spatial position relationship and biomechanical environment between different tissue structures of the craniofacial) applied by an instrument on the basis of natural growth potential; it may also refer to the process of purposeful intervention of the growth of some to all of the above-mentioned parts for preventive or purely aesthetic purposes, without the problem of facial deformity in the medical concept.

Further, since human craniofacial growth and development have different physiological characteristics at different periods, for example, the development of upper and lower jaws is not synchronous during the growth and development of jawbone, generally appears as a development lag of lower jaw, with the eruption of permanent teeth, the occlusion of upper and lower teeth forced to function needs leads the lower jaw to adapt to the positions of upper jaw and upper dentition in three-dimensional space, causing the change of the lower jaw position, and the secondary growth and reconstruction of temporomandibular joint, thereby coordinating the growth between different tissue structures of craniofacial, so in general, the above-mentioned guiding of craniofacial growth needs to be carried out in stages: in one craniofacial growth guide period, one personalized craniofacial growth guide is used, and in another craniofacial growth guide period which is not overlapped in time, the other craniofacial growth guide or the personalized craniofacial growth guide is used, and the number of the guide periods is generally determined according to factors such as the age of a guide object, the growth and development condition of each tissue structure of the craniofacial, the severity of tooth surface deformity or the gap between the expected effect to be realized and the initial state. The above-described at least two personalized craniofacial growth guides used in at least two mutually non-overlapping craniofacial growth guiding cycles constitute a craniofacial growth guiding system that guides a craniofacial growth process of a guided subject.

Referring back to fig. 1a to 1d, in the embodiment of the present application, the personalized craniofacial growth guide 8 includes an upper guide groove 81, a lower guide groove 82, and a plate 83, wherein the plate 83 is located between the upper and lower guide grooves to connect the upper and lower guide grooves as a whole. In the embodiment of the present application, the upper guide groove 81, the lower guide groove 82, and the plywood 83 are referred to as basic structural units of the personalized craniofacial growth guide 8.

Further, as shown in fig. 1a to 1d, the upper guide groove 81 is surrounded by an upper guide groove outer wall 811, an upper guide groove inner wall 812 and a plywood 83, and the groove body is arc-shaped and is used for accommodating and guiding the upper dentition, a part of the maxilla, a part of the upper gum and other soft tissues of the guiding object in the growth process; the lower guide sprouting groove 82 is formed by enclosing a lower guide sprouting groove outer wall 821, a lower guide sprouting groove inner wall 822 and a plywood 83, and the groove body of the lower guide sprouting groove is arched and is used for accommodating a part of soft tissues such as a lower dentition, a part of a mandible, a lower gum and the like of a guide object and guiding the growth process of the lower dentition, and meanwhile, the secondary growth and reconstruction of the temporomandibular joint of the guide object can be further guided through the connection of the plywood 83, so that the occlusion relation of the upper jaw and the lower jaw of the guide object is adjusted.

In some preferred embodiments, the personalized craniofacial growth guide 8 may be made of medical grade silicone or other similar soft and resilient material, by molding or other techniques known to those skilled in the art, and the upper and lower guide channels may be integrally formed with the outer walls, inner walls and plywood during manufacture, or may be separately formed and then assembled by bonding or other similar means.

Further, in some preferred embodiments, the grooves of the upper and/or lower guide channels 81, 82, and the inner and outer walls of the upper and/or lower guide channels 81, 82 further include various attachments thereon, for example, in some preferred embodiments, the grooves of the upper and/or lower guide channels 81, 82 include at least one retention attachment that retains the growth guide by means of teeth that have erupted and are in the correct position (location, posture), thereby helping the softer personalized craniofacial growth guide 8 to stabilize in the correct wearing position and to enhance the intervention applied to the various tissue structures of the craniofacial of the guide subject by means of teeth that have retained in the correct position; as another example, in some preferred embodiments, the groove body of the upper guide sprouting groove 81 and/or the lower guide sprouting groove 82 comprises at least one guide accessory, and the guide accessory is used for sprouting teeth which are sprouting or are to be sprouted to ideal directions and positions, and the guide accessory can be a space structure expanded along a guide path or an obstacle avoidance structure for blocking an error path; for example, in some preferred embodiments, at least one of a lip, a tongue, a cheek, and a tongue guide may be further included on the inner and outer walls of the upper and/or lower guide grooves 81 and 82, and the above-mentioned accessory may be used as a chewing organ guiding accessory, so as to guide or adjust the position, shape, etc. of the tissue structure at different positions inside and outside the oral cavity, respectively, and thus guide the functional state of the chewing organ as a whole.

In the embodiments of the present application, the shapes of the above-mentioned respective basic structural units, such as the shapes, patterns, angles and depths of the groove bodies of the upper guide groove and/or the lower guide groove, and the positions, shapes, sizes, etc. of the various accessories provided on the respective basic structural units are referred to as design parameters of the respective basic structural units, and the following table 1 lists the design parameters of the basic structural units that may be provided in some embodiments.

TABLE 1

Obviously, the design process of the personalized craniofacial growth guide comprises the core steps of correctly determining the above design parameters, and the guiding object can gradually guide the tissue structure of each part of the craniofacial to the target position in the corresponding craniofacial growth guiding period by wearing the personalized craniofacial growth guide designed and manufactured according to the above design parameters, so as to promote the growth guiding effect of the personalized craniofacial growth guide, the determination process of the above design parameters should follow the following principles:

a) The design of the craniofacial growth guide should be based on a reasonable medical concept, consider the chewing organ as a complete functional unit, respect the functional and aesthetic principles of the chewing organ, and achieve an optimal balance of personalized morphology and function of each patient's chewing organ;

b) The design of the craniofacial growth guide also needs to conform to physiological characteristics of human craniofacial growth and development at different periods, and the spatial position relation and biomechanical environment among different tissue structures of the craniofacial are changed in stages according to the personalized characteristics of the tooth surface deformity of a patient;

c) The design of the craniofacial growth guide also accords with the principle of functional syngeneics, and in the growth and development process of the craniofacial growth, the development of the upper jaw and the lower jaw are asynchronous, and the development of the lower jaw is lagged; with the eruption of the permanent teeth, the occlusion of the teeth of the upper and lower jaws, which is forced to function, guides the lower jaw to adapt to the positions of the upper jaw and the upper dental arch in a three-dimensional space, so that the position of the lower jaw is changed, and the temporomandibular joint is secondarily grown and reformed, so that the growth of different tissue structures of the craniofacial is coordinated.

d) Furthermore, the goal of guiding the sprouting of teeth and guiding the growth of jawbone needs to be realized in stages according to the physiological laws of occlusion development and jaw development, the teeth with supporting and fixing functions in each stage are different, the teeth with the sprouting needs to be guided are different, and the adjustment and growth guiding of a large number of jaw relative position relations in the same stage can be realized in steps, so that a corresponding personalized craniofacial growth guide device is designed for each craniofacial growth guiding period, and finally, a craniofacial growth guiding system suitable for the whole craniofacial growth stage is formed.

To this end, the present application also provides a method of designing the above personalized craniofacial growth guide, fig. 2 shows a flow chart of the above personalized craniofacial growth guide design method in some preferred embodiments, as shown in fig. 2, comprising the steps of:

step S100, obtaining an initial value of craniofacial parameter combination of a guiding object;

step S200, determining a target value of craniofacial parameter combinations of the guiding objects;

step S300, determining design parameters of basic structural units of the personalized craniofacial growth guide based on the target values;

step S400, opening occlusion of the guiding object on the closed frame based on the target value, and designing a personalized craniofacial growth guide based on the design parameters.

The steps described above are described in detail below with reference to the accompanying drawings and specific embodiments.

< step S100>

Step S100 is used to obtain the initial state of the parameters such as the position, the form, the relative relation, etc. of each part of the craniofacial surface of the guiding object at the initial stage of one craniofacial growth guiding period, and in the embodiment of the present application, the position, the form, the relative relation, etc. of the parts such as the teeth, the occlusion, the skull, the jawbone, the facial soft tissues, etc. of the craniofacial surface of the guiding object can be represented by the craniofacial parameter combination.

In some specific embodiments, the craniofacial parameter combinations include a set of facial feature parameters and/or a dental arch morphology.

1) Dental surface characteristic parameter set

Table 2 below shows an optional tooth surface feature parameter set and the index used therein, where the tooth surface feature parameter set may be formed by a two-dimensional matrix, where the two-dimensional matrix characterizes the tooth surface feature of the guiding object from two dimensions, one dimension is a tooth shape, a bone shape, and a surface shape, and the other dimension is a vertical direction, a sagittal direction, and a horizontal direction, and in the two-dimensional matrix forming the tooth surface feature parameter set shown in table 2, each element in the matrix may be an index known to those skilled in the art, for example, an FMA index may be used when the vertical bone shape feature of the guiding object needs to be characterized, and a side view convexity index may be used when the sagittal plane shape feature of the guiding object needs to be characterized.

TABLE 2

The above-mentioned indexes in the dental surface feature parameter set are different in importance, wherein the facial features of the guiding object in the vertical direction and the sagittal direction (i.e. the sublevel and the lateral convexity) and the dental features of the guiding object in the sagittal direction (i.e. the molar relationship) can effectively reflect the dental surface features of the guiding object, and thus, in some embodiments, the dental surface feature parameter set may be composed of the above three indexes; furthermore, in order to more fully evaluate the dental surface characteristics of the guiding subject, in other embodiments, a dental surface characteristic parameter set may be constructed by selecting all 9 indexes of the 3×3 matrix.

In addition to the two-dimensional set of dental surface characteristics described above, in some preferred embodiments of the present application, the set of dental surface characteristics further includes a plurality of dental surface performance parameters such as: tooth development stage, inverse condition, tooth pose, and resultant plane angle.

2) Dental arch curve

The maxillary dentition of the individual teeth of the human upper jaw, and the mandibular dentition of the individual teeth of the lower jaw are arranged substantially along a generally arcuate form, which in the art of stomatology may be characterized by curves of various functional forms, known as arches.

Specifically, by marking characteristic points on each tooth of the upper jaw and the lower jaw (for example, crown midpoint, or cusp, or cheek cusp of each tooth), and fitting each marked point, an initial arch curve of the guide object, that is, an initial value representing the shape of the arch before one craniofacial growth guide cycle starts, can be obtained.

Fig. 3a, 3b, 3c, 3d and 3e respectively show the form of each angle of the craniofacial face, each angle photograph of the inside of the oral cavity, the oral cavity X-ray Qu Duanpian, the craniofacial azimuth X-ray and the craniofacial forward X-ray of the guiding object before the beginning of one craniofacial growth guiding period in a specific embodiment, in addition, the three-dimensional solid model of the dental jaw of the guiding object can be generated according to the above data, the plane-merging angle can be measured on the mechanical frame, and the initial value of the above dental characteristic parameter set can be obtained by measuring and evaluating the above various data and the tissue structure information contained in the model, and the initial value of the guiding object dental characteristic parameter set in this embodiment is listed in table 3 below.

TABLE 3 Table 3

Further, after the feature points on each tooth are marked and fitted, the initial arch curve of the upper jaw and the lower jaw of the guiding object can be obtained, and furthermore, the initial arch curve obtained by fitting can be measured and analyzed, for example, by measuring and analyzing the initial arch curve of the guiding object shown in fig. 3a to 3e, the phenomenon of slight narrowing and deformation of the upper and lower arches before the beginning of the craniofacial growth guiding period can be determined, wherein the upper and lower front arches are crowded by 2mm.

< step S200>

For a guidance object that needs to be guided for craniofacial growth (e.g. the embodiments shown in fig. 3a to 3e and table 3), generally, before starting a craniofacial growth guidance cycle, there is a deviation from its ideal state of parameters in its craniofacial parameter set, i.e. its target value at the end of the craniofacial growth guidance cycle, for example, at least one of the indices in the set of facial feature parameters and/or at least one of its maxillary and mandibular arch curves, and/or at least one of its set of occlusal performances.

In the embodiment of the present application, the step S200 is used to determine the target value of the above-mentioned craniofacial parameter combination of the guiding object, and it is obvious that in the embodiment of the present application, the target value of the craniofacial parameter combination includes at least the target value of the dental facial feature parameter set and the target value of the dental arch morphology, preferably further includes the target value of the above-mentioned dental occlusion performance set.

In some preferred embodiments, as shown in fig. 4, the set of facial feature parameters and the target values for the arch morphology may be determined by:

and step A100, determining the adjustment direction of each parameter in the craniofacial parameter combination.

For each parameter adjusting direction, the tooth eruption time sequence, the jaw bone growth trend, the growth type and the oral cavity function characteristics are determined according to the occlusion development period of the guiding object, for example, in some preferred embodiments, the facial feature parameter set and the dental arch form are analyzed to determine the facial deformity cause and the influence degree according to the steps shown in fig. 4, and then the mandible movement strategy, the tooth movement strategy and the facial soft tissue adjusting strategy are sequentially formulated according to the analysis result.

Specifically, for the analysis of the cause of the dental surface deformity and the extent of its influence, it is possible to perform the analysis in the vertical direction, the sagittal direction and the horizontal direction of the guiding object, respectively, wherein the following steps are sequentially performed in each direction:

Firstly, extracting the facial type parameters and bone type parameters of the direction;

secondly, determining whether the guiding object has abnormal jawbone morphology in the direction according to the bone type parameters in the direction;

thirdly, determining whether the soft tissue is abnormal in morphology according to the relative relation between the bone type parameter and the surface type parameter in the direction;

step four, extracting the dental model parameters in the direction, and determining whether the jaw position relationship is abnormal or not in the direction according to the dental model parameters in the direction;

and fifthly, determining the influence degree of each tooth surface deformity cause in the direction.

In the above steps, the mechanism of forming the facial morphology of the guiding object is first disassembled and analyzed by the relative relationship between the facial form and the bone form, and the morphological characteristics of the soft tissue, that is, the coverage characteristics of the soft tissue relative to the jawbone, can be determined according to the relative relationship between the bone form parameter and the facial form parameter, so that it can be determined whether different facial morphologies are caused by abnormal bone forms, or caused by abnormal morphological forms of the soft tissue of the craniofacial (that is, normal bone forms and tooth forms), or caused by both, for example: when the guided subject has a problem of facial deformity in the sagittal direction and the facial parameters (side convexity values) are consistent with the bone-type parameters (ANB values), it is considered that the coverage of the soft tissue is not the cause of the guided subject in the sagittal direction; when the lateral aspect convexity value of the guide subject deviates from the normal range more than the ANB value, the cause of the sagittal tooth surface deformity of the guide subject can be considered to include morphological abnormality of soft tissue itself in addition to bone type abnormality.

Then, the tooth profile parameters of the guiding object are extracted, for example, whether the tooth of the guiding object has abnormal tooth/bone position relationship in the sagittal direction (such as the tooth grinding near middle movement caused by the early deciduous tooth loss) can be determined according to the tooth profile parameters in the sagittal direction, and the sagittal position relationship of the mandible is classified into class I (normal), class II (mandibular retroversion) and class III (mandibular forward movement) according to the tooth grinding relationship, wherein the abnormal tooth/bone position relationship and the mandibular retroversion and the mandibular forward movement (namely the abnormal jaw position relationship) are the causes of sagittal tooth surface deformity.

Finally, the various causes of the facial deformity of the guiding object in the direction obtained in the front are synthesized, and the influence degree of each cause is evaluated based on craniofacial morphology, so that the analysis of the facial deformity causes and the influence degree in the direction is completed.

Step a200, determining a target position of the mandible relative to the maxilla.

Specifically, the target position of the mandible corresponding to the maxilla can be determined by at least one of clinical diagnosis, facial arch transfer, mechanical frame combination adjustment on a dental jaw three-dimensional solid model, virtual fitting frame adjustment on a dental jaw digital three-dimensional model, and the like, and the guiding object shown in fig. 3a is still taken as an example for explanation, and according to analysis based on basic dental surface deformity characteristics, the mandible needs to be rotated and reset to the right side so as to correct mandible left deviation, left side reverse combination and mandible left deviation; simultaneously, the lower jaw is retreated as far as possible so as to correct anterior tooth retrofits and improve the concave surface shape, for this purpose, the relative position relationship of the upper dental arch, the lower dental arch and the jaw bone is firstly recorded by using an occlusion recording material, then the upper mechanical occlusion frame is transferred through the anatomical surface arch, and then the parameters of the mechanical occlusion frame are adjusted so that the lower jaw of the dental three-dimensional entity model on the mechanical occlusion frame can be ideally occluded relative to the upper jaw (namely, the target occlusion relationship is determined), or the parameters of the virtual fitting frame are adjusted in virtual occlusion frame operation software so that the lower jaw of the dental three-dimensional digital model on the virtual fitting frame can be ideally occluded relative to the upper jaw. Fig. 5 shows the relative positional relationship of the dental three-dimensional model in the target state on the occlusion frame.

Step a300, determining and designing target values of the respective parameters in the craniofacial parameter combination of the guidance object.

In this step, the target values for the individual parameters in the craniofacial parameter combination may be determined according to functional and aesthetic principles of occlusion, such as: target values of parameters such as a target dental arch curve, an occlusal plane angle and position/upper and lower anterior tooth angle and inclination/upper and lower molar position.

It should be noted that, as described in the foregoing steps, the initial value and the target value of the craniofacial parameter combination of the guiding object are determined, and different steps are required to be followed, wherein, when the target value of the guiding object is determined, the external features of the facial soft tissue are basically analyzed first, and then the features of the bones and the teeth and the influence of the features on each other are analyzed inwards, so that various causes of the facial deformity and the influence degree of the facial deformity are determined gradually and deeply; the method is characterized in that the target value of the craniofacial parameter combination is determined, firstly, the desired alignment relation of the upper and lower jaws in the three-dimensional space is set, then, the aesthetic principle and the functional principle are utilized, the personalized dental arch form, the occlusion between the upper and lower dental arches, the position of the dental arch on the jaws, the angle and position of the upper and lower front teeth, the angle and position of the occlusal plane and the like are designed, and the reason for adopting the steps is that the bone form and the development condition are the basis that each tissue of the craniofacial can realize growth in an ideal direction, the target state can be realized as soon as possible through growth guidance, and the further adjustment of the teeth and facial tissues is facilitated by taking the dental arch form as a bracket.

< determination of target dental archwire >

The manner of determining the target dental arch curve, the arcuate adjustment for the problem of the dental arch state of the guide subject is an important step for the growth of the guide cranium in the ideal direction, because by adjusting the dental arch to the ideal arch, the necessary basis can be provided for the ideal arrangement of the dentition. There are many methods for generating or determining the ideal arch, however, they are often manually performed by experience of a doctor or technician, or one closest to the guiding object is selected from several pre-established ideal arches, and the above methods cannot ensure that the generated arch curve form meets the functional requirements of dental development and dentition arrangement, and also do not consider the difference between the development stage and development speed of the dental jaw in different areas, so that the method is often not most suitable for guiding the target arch curve of the object, and therefore, a more reasonable way for determining the target arch curve needs to be provided.

Fig. 6 illustrates a flow chart of determining a target dental arch curve of a guided subject over a craniofacial growth guidance cycle in some preferred embodiments of the application, the target dental arch curve being generated by the steps of:

And step B100, marking the tooth characteristic points of the guiding object.

Specifically, labeling of tooth feature points can be performed on a three-dimensional digital model of the dental jaw of the guiding object or on images such as curved fragments for subsequent measurement and generation of a target dental arch curve. It is found that, by shifting the target dental arch curve of the lower jaw outwards by 2.5mm, an upper jaw target dental arch curve meeting aesthetic and functional requirements can be obtained, so in the embodiment of the application, the target dental arch curve of the lower jaw can be generated first, and then the upper jaw target dental arch curve can be generated based on the target dental arch curve of the lower jaw.

The marking of the tooth characteristic points can be performed manually or automatically, and the tooth characteristic points can be the tooth cusp points on the crowns of the specific teeth, the near middle cheek cusp points or the far middle cheek cusp points and other specific position points on the jaws known to the person skilled in the art, for example, the incisor midpoints of the left tooth and the right tooth 1, the incisor midpoints of the left tooth and the right tooth 2, the tooth cusp points of the left tooth and the right tooth 3, the cheek cusp points of the left tooth and the right tooth 4, the cheek cusp points of the left tooth and the right tooth 5, the near middle cheek cusp points and the far middle cheek cusp points of the left tooth and the right tooth 6, and the near middle cheek cusp points and the far middle cheek cusp points of the left tooth and the right tooth 7 can be marked on the jaws respectively.

Step B200, measuring and obtaining the first characteristic parameters C of the guiding objects respectively ₁ Second characteristic parameter C ₂ 。

In an embodiment of the application, the first characteristic parameter C ₁ Second characteristic parameter C ₂ Refers to an amount having the following properties: in one aspect, C ₁ 、C ₂ The inherent characteristics of a dental jaw in a craniofacial growth guide cycle are characterized irrespective of changes in dental arch morphology during the guide cycle, i.e. in a craniofacial growth guide cycle, regardless of whether the jaw is already in the ideal arch state in which the guide cycle should be in, its C ₁ 、C ₂ The values of (2) remain unchanged; on the other hand, C ₁ 、C ₂ Has different definition modes in the complete process of craniofacial growth, namely C when the complete process of craniofacial growth is divided into guide periods which are not overlapped with each other in time ₁ 、C ₂ The values may be determined from the characteristics of different tooth combinations during different guide periods.

In some preferred embodiments, C ₁ Determining by geometric features of a first set of teeth, wherein the first set of teeth comprises a plurality of specific teeth of the upper or lower jaw of a specific dental jaw; c (C) ₂ Is determined by the geometry of the second set of teeth, wherein the second set of teeth is a proper subset of the first set of teeth, i.e. the first set of teeth contains and more than all teeth of the second set of teeth.

Taking the dental chart shown in FIG. 7 as an example, in some embodiments, the first set of teeth may comprise a total of 10 teeth, L5 through R5, and, correspondingly, a first characteristic parameter C ₁ For the sum of the crown widths of 5-5 of the lower jaw, i.e., the sum of crown widths of the teeth L5 to R5 in FIG. 7 (it is to be noted that, in the present application, the sum of crown widths n1-n2 means a result of measuring the tooth Ln1 to Rn2 of the left side of the upper jaw or lower jaw, obtaining crown widths of each tooth and superposing them), the second set of teeth is a proper subset of the first set of teeth including 4 teeth L2 to R2, and accordingly, the second characteristic parameter C ₂ The second set of teeth may also comprise 6 teeth L3 to R3 or 8 teeth L4 to R4, respectively, and the second characteristic parameter C ₂ 3-3 crown width sum or 4-4 crown width sum of mandible; in other embodiments, at L5When the teeth No. or R5 are not erupted or in a stable state, the first tooth set can only comprise 8 teeth from L4 to R4 of the lower jaw, the second tooth set is 6 teeth from L3 to R3 of the lower jaw or 4 teeth from L2 to R2 of the lower jaw, and at the moment, the first characteristic parameter C ₁ For the sum of the width of the 4-4 crowns of the mandible, the second characteristic parameter C ₂ Is the 3-3 crown width sum or the 2-2 crown width sum of the lower jaw.

Step B300: based on the first characteristic parameter C ₁ Determination of a first ideal dental arch characteristic R ₁ According to R ₁ Determining a first curve of the form:

Y＝AX ⁴ +BX ² ，

wherein X, Y is the coordinates of each point on the curve and X, Y is on the jaw plane, the X axis and Y axis are orthogonal, the Y axis corresponds to the projection of the median sagittal plane on the jaw plane, A, B is the coefficients of the fourth term and the second term of the first curve and is perpendicular to the R ₁ The coupling is correlated.

Step B400: based on the second characteristic parameter C ₂ Determination of a second ideal dental arch characteristic R ₂ According to R ₂ Determining a second curve of the form:

step B500: and splicing the part of the first curve in the first dentition interval and the part of the second curve in the second dentition interval to obtain the target dental arch curve of the guiding object in one craniofacial growth guiding period.

Step B300 and B400 are respectively performed by the first characteristic parameters C ₁ And a second characteristic parameter C ₂ Obtaining a first ideal dental arch characteristic parameter R_1 and a second ideal dental arch characteristic parameter R ₂ Then based on R ₁ 、R ₂ And B500, cutting the two curves and splicing the two curves to obtain a final target dental arch curve.

And C ₁ 、C ₂ In the present application, differentlyIn an embodiment of (a), a first ideal dental arch characteristic parameter R ₁ And a second ideal dental arch characteristic parameter R ₂ Characterizing features on a dental jaw which, when in an ideal arch form in which a certain craniofacial growth is to be conducted, are found which relate only to the ideal arch curve, i.e. if R is determined ₁ 、R ₂ A target dental arch curve describing the ideal arch can also be determined. Wherein, in some preferred embodiments, a first desired dental arch characteristic R ₁ In order to guide the jaw of the subject to a desired arch, the 5/6 abutment dimension of the jaw (in the present application, the m1/m2 abutment dimension means the distance between the abutment points of the m1 st tooth and the m2 nd tooth on both sides of the upper jaw or the lower jaw, and in the example of fig. 4, the 5/6 abutment dimension means the distance between the abutment points of the L5 th and L6 th teeth on the left side and the abutment points of the R5 th and R6 th teeth on the right side).

Applicant finds that C by carrying out statistical analysis on a large amount of normal dental data meeting aesthetic evaluation criteria and functional evaluation criteria ₁ And R is R ₁ And C ₂ And R is R ₂ There is a statistical correlation, so C can be obtained in advance by counting a plurality of normal dental data ₁ /R ₁ 、C ₂ /R ₂ Further, C of the guiding object is measured ₁ 、C ₂ Then, the R corresponding to the ideal bow is determined by using the statistical relationship ₁ 、R ₂ At the same time due to R ₁ 、R ₂ Statistics of normal dental jaw from a population meeting both normal aesthetic and functional criteria, independent of physician or technician experience, thereby resulting in a product of C ₁ 、C ₂ Determination of R ₁ 、R ₂ The subjective factor influence is undoubtedly eliminated in the process of (1) so that the generation of the target dental arch curve is more in line with the physiological characteristics of the self growth and development of the guide object.

In addition, the reason why the target dental arch curve is obtained by using the curve concatenation of two different shapes is that, first, the dental arch state is described by simply using a curve of one functional form, for example, a beta function curve, a fourth order curve, etc., while a fitting parameter that satisfies the minimum cost function as a whole can be found mathematically, in a partial dentition section, for example, an anterior dentition section, the shape may be different from the optimal shape conforming to the functional and developmental characteristics.

Fig. 8 shows the result of fitting a real tooth jaw according to the ideal arch state standard by using the 4-degree function, and as shown in fig. 8, although the arch curve obtained by fitting can meet the minimum overall cost function of each mark point on the tooth row, the curve shape of the front tooth area is closer to a rounded trapezoid, however, according to the analysis of the geometric characteristics of each front tooth of the tooth jaw (such as the crown width of the left 3-right 3 teeth), the arrangement of the front teeth is found to be more approximate to a circle, and obviously, by describing the curves of different function forms for different tooth row areas, although the arch curve with non-minimized cost function can be obtained mathematically, the function requirement of the arch shape is met.

Secondly, for the guiding object in the craniofacial growth stage, the dental arch not only presents different dental arch forms in each area, but also presents obvious differences in the development speed and development state of each area in the dental arch development process, the relation between the ideal dental arch forms of each area is continuously changed, and the characteristics that the ideal dental arch curve is changed in stages and in regions are formed on the whole are formed, so that the combined personalized target dental arch curve of the specific dental arch is required to be established in stages and in regions of dentition, and the combined personalized target dental arch curve can be more attached to the development characteristics of the dental arch.

For the above reasons, in the embodiment of the present application, the first curve is in the form of a 4-degree function curve, which is mainly used to represent the ideal dental arch shape of the posterior dental area, and the second curve is in the form of a perfect circle, which is mainly used to represent the ideal dental arch shape of the anterior dental area, and the target dental arch curve is obtained by splicing the two curves.

Further, by analyzing the measured data of the plurality of normal dental jaws, it is found that since the first curve comprises at least two polynomial coefficients A, B, the two polynomial coefficients together affect the curve shape and their effects are coupled to each other such that A, B and R ₁ Is integrally coupled withIt is therefore desirable to construct an intermediate arch curve through which R is established ₁ And A, B, for which purpose, in some preferred embodiments, R is determined by ₁ Relationship with A, B:

step B310, obtaining a plurality of optimal dental arch curves of normal dental jaw meeting functional and aesthetic standards, wherein the optimal dental arch curves and the first curves have the same functional form, and two coefficients A thereof _best 、B _best Fitting the determination based on the measured data for each normal dental jaw.

Specifically, the corresponding optimal arch curve can be fitted from the measured data of each reference dental jaw by methods known to those skilled in the art.

Step B320, obtaining an intermediate dental arch curve of each normal dental jaw, wherein the intermediate dental arch curve and the first curve have the same function form, and two coefficients of the intermediate dental arch curve comprise a fixed coefficient A _mean And a variable coefficient B _adjust Wherein the coefficient A is fixed _mean According to the corresponding coefficient A in each optimal dental arch curve _best Is determined by the statistical value of the variable coefficient B _adjust Fitting determination is based on the measured data of the normal dental jaw.

Specifically, first for coefficient A in a plurality of optimal dental arch curves _best Statistics are carried out to obtain statistical values, such as average values, which are used as fixed coefficients A _mean Then, under the condition of constant fixed coefficients, fitting to obtain the intermediate dental arch curve of each normal dental jaw, wherein the coefficient B (i.e. variable coefficient) of the intermediate dental arch curve is obviously different for different reference dental jaws and is marked as B _adjust . In this way, an optimal dental arch error with each normal jaw can be obtained which is sufficiently small, but which contains only one intermediate dental arch of variable coefficients.

Step B330, statistical determination B _adjust And A is a _best 、B _best R is R ₁ Is a relationship of (3).

Through correlation statistics, the variable coefficient B _adjust Two coefficients A respectively corresponding to the optimal dental arch curve,B and a first ideal dental arch characteristic parameter R ₁ Statistically strongly correlated so that it can be used as a "bridge" to build R ₁ And A, B, so that in step B330, the first desired dental arch characteristic R for each normal dental jaw is determined ₁ And variable coefficient B _adjust Is a statistical relationship of the respective normal dental coefficients B _adjust Relationship with the coefficient A, B of the optimal arch curve, determined as R ₁ Coefficients A, B of the first curve of the characterized guidance object, and thus according to C ₁ And R is R ₁ The relation of (C) ₁ Coefficient A, B of the first curve of the characterized guidance object, due to the first parameter C ₁ Is the amount by which the jaw of the subject remains unchanged during a craniofacial growth guide cycle, the method automatically generates a first curve from measurable data of the jaw of the subject prior to the guide cycle.

Based on a similar embodiment, in step B400, the second curve may be automatically generated by the measurable data of the dental jaw of the guiding subject before the guiding period, which is not described here again.

After the first curve and the second curve are obtained through the above steps, in step B500, the portion of the first curve located in the first dentition interval and the portion of the second curve located in the second dentition interval are spliced, so that the target arch curve of the dental jaw of the guidance object corresponding to one craniofacial growth guidance period can be obtained, wherein in some preferred embodiments, the first dentition interval is a left-side and right-side rear dentition area, the second dentition interval is a front dentition area, and further, the boundary point of the first dentition interval and the second dentition interval is located in the projection area of the cuspid on the jaw plane.

Since the first curve and the second curve may have a misalignment at the interface between the first dentition interval and the second dentition interval, in some preferred embodiments, the truncated first curve and the second curve may be connected by a transition curve, wherein the transition curve may be generated by:

Firstly, intercepting a part of a first curve in a first dentition interval to a posterior tooth area by a specific length;

a transition curve is then generated based on a fit of the remaining portion of the first curve to the portion of the second curve that is in the second dentition interval.

In particular, it should be noted that the specific length of the cut-out is neither too small to avoid causing severe turning when the first curve is spliced with the second curve, nor too large to avoid excessively large deviation of the morphology of the fitted target curve caused by excessive cutting-out, and in some preferred embodiments, the specific length of the cut-out is greater than or equal to the crown length of the first premolars and less than or equal to 10mm.

< step S300 and step S400>

After the target values of the craniofacial parameter combinations are obtained through step S200, the design parameters of the basic structural units of the personalized craniofacial growth guide may be determined according to the target values in step S300.

In some specific embodiments, the basic structural elements of a personalized craniofacial growth guide may be first constructed, each structural element corresponding to a design parameter of a target site, each parameter being set to a range in which adjustment is permitted according to the characteristics of the preselected guide material (elasticity, stiffness, ductility, etc.), and the growth guide process is decomposed to obtain a treatment target site corresponding to a craniofacial growth guide cycle.

Then, through step S400, on the mechanical frame or the virtual fitting frame, the occlusion of the guiding object is opened according to the target occlusion relation of the lower jaw relative to the upper jaw, so that a space is opened for accommodating each basic structural unit of the personalized craniofacial growth guide, then each basic structural unit is designed according to the design parameters obtained in step S300, and finally, the entity model of the personalized craniofacial growth guide or the three-dimensional digital model of the virtual personalized craniofacial growth guide is obtained through an integral or combined mode.

Further, in some preferred embodiments, as described above, the personalized craniofacial growth guide includes, in addition to the basic structural elements, various accessories within the grooves of the upper and/or lower guide channels, and on the inner and outer walls of the upper and/or lower guide channels, it being apparent that the design parameters of the various accessories should be selected to be appropriate parameters based on the function they achieve, as to whether they are designed in the target position, and for this purpose, in some preferred embodiments, the craniofacial parameter combinations further include the morphology of the individual teeth of the subject (including eruption phase, pose, etc.), as well as the functional status of the chewing organs of the subject (including the functional status of the various parts of the tongue, lips, cheeks, etc.).

According to the above-mentioned target value of tooth morphology and target value of masticatory organ function state, various accessory structures can be added on the basis of basic structural unit, for example, deciduous teeth whose root development is basically completed and whose root absorption is not more than 1/2 of root length can be used as retaining teeth, and the retaining accessories correspondent to the retaining teeth can be added in the correspondent position of basic structural unit, and the position of craniofacial growth guide in mouth can be stabilized by using said retaining accessories; for another example, at least one guiding accessory is added respectively to lead the teeth which are or are about to erupt to ideal directions and positions, and the erupted teeth with dislocation are corrected; for another example, at least one of a lip stop, a tongue stop, a cheek screen and a tongue position guide can be added into the personalized craniofacial growth guide according to the ideal functional state to be realized by the chewing organ.

Furthermore, in the whole craniofacial growth guiding process of a guiding object, because the development stages and the speeds of different parts are different, the growth guiding process is often required to be divided into 2, 3 or more craniofacial growth guiding periods, and corresponding personalized craniofacial growth guides are respectively designed for each period, and the at least two personalized craniofacial growth guides corresponding to different periods can form a whole craniofacial growth guiding system, so that the growth guiding is continuously provided for the guiding object in the craniofacial growth and development process.

Taking the guiding objects shown in fig. 3a to 3e as an example, the guiding objects start to erupt after about 12 months (i.e. the constant teeth 6, 1 and 2 on the left side and the right side), when the personalized craniofacial growth guiding device used in the current guiding period is designed, milk III, IV and V can be used as retention teeth to stabilize the relative position relationship between the upper jaw and the lower jaw, so that the guiding objects can maintain the treatment target position and ensure the normal growth of the jaw when the guiding objects wear the growth guiding device at night, and therefore, the retention accessories can be designed on milk III, IV and V to increase the stability of the growth guiding device and maintain the effect of the jaw position.

Meanwhile, target positions of 6, 1 and 2 required by the constant teeth can be reserved on the craniofacial growth guide, so that the constant teeth can automatically erupt to the positions for realizing ideal arrangement and dental arch morphology as far as possible according to the eruption route and the eruption space reserved on the growth guide: 1. 2 is positioned more labially than the current breast I, II and establishes normal anterior occlusion coverage to achieve the desired aesthetics and function; the upper left 6 is more than the upper right 6 to sprout out, so that the inconsistency of the right and left side closing planes is corrected.

To ensure that there is sufficient material space between the upper and lower jaws to accommodate the growth guide, to ensure retention, resistance and tolerance of the growth guide, the bite space between the upper and lower arches can be properly opened on the jig according to the desired material properties.

After these teeth develop, the subject is guided into the next craniofacial growth guide cycle, at which time the newly erupted 6, 1, 2 teeth can support jaw sites, and then new clinical data can be submitted to design the next personalized craniofacial growth guide, with constant 6, 1, 2 as retention teeth, helping the growth guide to stabilize jaw site relationship, reserving the required eruption path and target sites for the next step of eruption constant 3, 4, 5.

Fig. 9 shows the occlusion of teeth after the guide object shown in fig. 3a to 3e is guided by using the craniofacial growth guide system provided by the embodiment of the present application for about 3 years, and it can be seen from fig. 9 that the problem of deformity existing in each part of the craniofacial of the guide object is better improved and growth is performed in a desired direction.

While the foregoing is directed to embodiments of the present application, other and further embodiments of the application may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

1. A method of designing a personalized craniofacial growth guide comprising the steps of:

2. The personalized craniofacial growth guide design method of claim 1, wherein the craniofacial parameter combination comprises:

a set of dental surface characteristic parameters and/or a dental arch morphology of the subject is guided.

3. The personalized craniofacial growth guide design method of claim 2, wherein the set of facial feature parameters comprises:

facial features of the guided object in the vertical and sagittal directions and dental features of the guided object in the sagittal direction.

4. The personalized craniofacial growth guide design method of claim 3, wherein the set of facial feature parameters further comprises:

bone-type, tooth-type features of the guiding object in the vertical direction, bone-type features of the guiding object in the sagittal direction, and facial-type, bone-type and tooth-type features of the guiding object in the horizontal direction.

5. The personalized craniofacial growth guide design method of claim 2, wherein:

the initial values of the arch morphology are characterized by an initial arch curve and the target values of the arch morphology are characterized by a target arch curve.

6. The personalized craniofacial growth guide design method of claim 5, wherein the target dental arch curve is generated by:

marking the tooth characteristic points of the guiding object;

measuring the first characteristic parameters C of the guide object ₁ Second characteristic parameter C ₂ ；

Y＝AX ⁴ +BX ² ，

7. The personalized craniofacial growth guide design method of claim 6, wherein:

the C is ₁ 、C ₂ The same craniofacial growth guiding period of the guiding object is kept unchanged, and ₁ 、C ₂ different craniofacial growth guide periods of the guide object have different defining modes;

8. The personalized craniofacial growth guide design method of claim 6, wherein:

the first dentition interval is a left-side and right-side rear dentition interval; and, the second dentition interval is an anterior dentition interval.

9. The personalized craniofacial growth guide design method of claim 8, wherein:

the junction point of the first dentition interval and the second dentition interval is positioned in the projection area of the cuspids on the jaw plane.

10. The personalized craniofacial growth guide design method of claim 1, wherein the basic structural unit comprises:

upper guide sprouting groove, lower guide sprouting groove and plywood for connecting upper guide sprouting groove and lower guide sprouting groove.

11. The personalized craniofacial growth guide design method of claim 10, wherein the design parameters comprise:

The shape, style, angle and depth of the upper guide sprouting groove and the lower guide sprouting groove.

12. The personalized craniofacial growth guide design method of claim 2, wherein the craniofacial parameter combination further comprises a morphology of each tooth of the guide subject.

13. The method of designing a personalized craniofacial growth guide of claim 12, further comprising the steps of:

adding at least one retention attachment to the personalized craniofacial growth guide, the retention attachment being designed to retain the craniofacial growth guide on deciduous teeth where root development is substantially complete or deciduous teeth where root absorption does not exceed 1/2 of root length.

14. The method of designing a personalized craniofacial growth guide of claim 12, further comprising the steps of:

at least one guide accessory is added to the personalized craniofacial growth guide, wherein the guide accessory enables teeth which are erupting or are about to erupt to an ideal direction and position.

15. The personalized craniofacial growth guide design method of claim 2, wherein the craniofacial parameter combination further comprises guiding a functional state of a masticatory organ of a subject.

16. The method of designing a personalized craniofacial growth guide of claim 15, further comprising the steps of:

at least one of a lip shield, a tongue shield, a cheek shield and a tongue position guide is added into the personalized craniofacial growth guide.

17. A personalized craniofacial growth guide comprised of a plurality of basic structural units, characterized by:

the basic structural unit comprises an upper guide germination groove, a lower guide germination groove and a plywood for connecting the upper guide germination groove and the lower guide germination groove;

the personalized craniofacial growth guide is designed and generated by the design method of the personalized craniofacial growth guide of claim 1.

18. A craniofacial growth guidance system, characterized by:

comprising at least two personalized craniofacial growth guides according to claim 17 for guiding a craniofacial growth process of a guided subject in at least two mutually non-overlapping craniofacial growth guide cycles, respectively.