A partitioned mandibular and tongue protrusion appliance based on magnetic driving and a preparation method thereof

Abstract

A partition type mandibular and tongue forward moving appliance based on magnetic force driving and a preparation method thereof, comprising an appliance main body formed by combination of an upper appliance and a lower appliance; the appliance main body comprises a front tooth area appliance for moving the tongue forward by using negative pressure to improve the ventilation effect and a back tooth area appliance for providing mandibular forward moving force to the mandible by using magnetic force, the front tooth area appliance comprises an arc-shaped body for preventing mouth breathing, and the arc-shaped body connects the upper appliance and the lower appliance to form an integrated structure of the appliance main body; compared with the prior art, the back tooth area appliance applies magnets to the inside of the appliance, changes the stress distribution on the dentition by adjusting the repulsion surface angle and the magnetic force size, carries out simulation calculation based on the biomechanics of the stomatognathic system, obtains the optimal magnetic force size and direction, provides biomechanical basis for obtaining more accurate magnetic force, avoids clinical complications such as change of occlusal relationship and temporomandibular joint disorder, and ensures the accuracy and safety of the forward moving force.

Description

Technical Field

[0001] This invention relates to the field of orthodontic appliances for obstructive sleep disorders, specifically to a magnetically driven, zoned mandibular and tongue-moving orthodontic appliance and its preparation method. Background Technology

[0002] The mandibular advancement appliance is an oral device used to treat sleep apnea and hypoventilation caused by narrowing of the pharynx during sleep. Using the maxillary dentition as a fulcrum, the appliance fixes the mandible in a protruding and slightly lowered position, moving the tongue and related soft tissues forward. This restructures and expands the upper airway structure, enhancing its stability and effectively relieving airway obstruction, reducing respiratory disturbances and snoring. Using a mandibular advancement appliance can significantly improve sleep-disordered breathing, thereby increasing daytime alertness and work efficiency, improving quality of life, and helping patients participate in social interactions in a healthier and more active state.

[0003] Current mandibular advancement appliances are often single-module designs. The forward force applied to the mandible is directly and rigidly transmitted to all teeth in the entire upper and lower dental arches through the appliance as a whole, generating unnecessary torque and causing the teeth to tilt and move, making it difficult to change the pressure distribution in different dental areas. To ensure retention and advancement effect, high-hardness thermoplastic polymer materials are generally used and mechanical drive is achieved by screws or clips, resulting in a strong foreign body sensation, significant gingival compression, and the application of unidirectional, rigid thrust without cushioning. Long-term wear puts excessive force on the dentition and temporomandibular joint, leading to poor oral comfort and side effects such as dry mouth, excessive salivation at night, facial swelling in the morning, and discomfort in the teeth or temporomandibular joint.

[0004] With the gradual maturation of medical 3D printing and computer-aided design technologies, customized mandibular advancement appliances have emerged. These appliances utilize high-precision manufacturing processes to ensure a perfect fit between the appliance and the dental surface, improving wearing stability and allowing for precise adjustment of the mandibular advancement distance, thus reducing adverse events. However, the adjustment mechanisms of existing customized mandibular advancement appliances are generally located on the outer surface of the appliance, increasing its thickness and making the foreign body sensation more pronounced. Furthermore, they lack the function of pushing the tongue forward, offering no significant improvement for upper airway obstruction caused by the posterior displacement of the tongue root.

[0005] The digitalization and intelligentization of mandibular advancement appliance design, manufacturing, and application are current development trends, providing new technological means to make mandibular advancement appliances more comfortable to wear, faster to manufacture, and with real-time effect monitoring capabilities. If a mandibular advancement appliance can provide a gentle mandibular advancement force while simultaneously allowing the tongue to move forward, it will be more comfortable to wear than current rigid appliances, and the forward movement of the tongue will ensure airway opening.

[0006] Chinese patent CN119279815A discloses a novel mandibular protrusion appliance and its digital manufacturing method. The appliance has a vestibular shield on the labial side of the lower anterior teeth. This appliance can not only effectively close the oral cavity and improve the dry mouth symptoms that may occur when wearing traditional mandibular protrusion appliances, as well as the mouth breathing problem that is common in patients with obstructive sleep apnea-hypopnea syndrome, but also significantly reduce the limitation of labial inclination of the lower anterior teeth caused by traditional mandibular protrusion appliances.

[0007] The aforementioned orthodontic appliances are rigid, and the force and direction they apply can easily cause temporomandibular joint discomfort, tooth soreness, and muscle fatigue, leading to decreased patient compliance. Summary of the Invention

[0008] The present invention aims to overcome the defects in the prior art and provide a magnetically driven, partitioned mandibular and lingual advancement orthodontic appliance with good adaptability, therapeutic effect and comfort, and its preparation method.

[0009] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a magnetically driven, zoned mandibular and lingual protraction appliance, comprising an appliance body formed by combining an upper appliance and a lower appliance; the appliance body includes an anterior tooth appliance that uses negative pressure to move the tongue forward to improve ventilation and a posterior tooth appliance that uses magnetic force to provide mandibular protraction force; the anterior tooth appliance includes an arc-shaped body for preventing mouth breathing, the arc-shaped body connecting the upper and lower appliances to form an integrated appliance body; the posterior tooth appliance includes an upper posterior tooth correction area located on the upper appliance and a lower posterior tooth correction area located on the lower appliance, the upper and lower posterior tooth correction areas being arranged opposite each other, and corrective magnets forming like poles that generate repulsive forces are installed in the upper and lower posterior tooth correction areas; the upper and lower posterior tooth correction areas are formed with magnet mounting slots for adjusting the angle of the repulsive surfaces.

[0010] As a preferred embodiment of the present invention, the arc-shaped body has a hole formed in the middle for the treatment end of the negative pressure device to pass through.

[0011] As a preferred embodiment of the present invention, the posterior orthodontic appliance is formed with a magnet holder for mounting orthodontic magnets, the magnet holder being formed on the occlusal surface of the posterior orthodontic appliance.

[0012] In a preferred embodiment of the present invention, the magnet mounting groove is formed on the surface of the magnet placement seat, and the corrective magnet is embedded in the magnet mounting groove.

[0013] As a preferred embodiment of the present invention, the orthodontic magnet embedded in the upper posterior teeth orthodontic area has a trapezoidal structure with its size gradually decreasing from top to bottom, and the orthodontic magnet embedded in the lower posterior teeth orthodontic area has a trapezoidal structure with its size gradually increasing from top to bottom.

[0014] A method for fabricating a magnetically driven, segmented mandibular and lingual advancement appliance, comprising the following steps:

[0015] Step S1: Three-dimensional reconstruction of the oral and maxillofacial model. Obtain intraoral scan data of the patient and obtain a three-dimensional model of the oral and maxillofacial system with the jawbone system and dental arch model based on the data.

[0016] Step S2: Construct the base model of the orthodontic appliance, and prepare the upper and lower orthodontic appliance base models that fit the dentition based on the dental arch model;

[0017] Step S3: Orthodontic appliance main structure design. The upper and lower orthodontic appliance base models are assembled in the software to the appropriate forward and downward position, and an arc-shaped body is constructed to connect the upper and lower orthodontic appliance base models to form the main body of the orthodontic appliance.

[0018] Step S4: Stress analysis of the stomatognathic system. Construct a biomechanical model of the stomatognathic system based on muscle force, consisting of the mandible, tooth roots and periodontal ligament, temporomandibular joint and articular disc. Based on the periodontal ligament bone-promoting strain threshold and the articular disc deformation threshold, obtain the optimal mandibular forward movement force and magnetic force based on the stress threshold of the stomatognathic system.

[0019] Step S5: Determine the size and placement angle of the corrective magnet according to the required magnetic force;

[0020] Step S6: Preparation of the main body of the orthodontic appliance. The corresponding mold is printed using 3D printing technology. The main body of the orthodontic appliance is formed by hot pressing the mold, and the orthodontic magnet is installed into the magnet holder.

[0021] As a preferred embodiment of the present invention, step S3 further includes the following sub-steps:

[0022] Step S3.1: Divide the main body of the orthodontic appliance into anterior and posterior regions, using the distal proximal surfaces of the canines as the boundary;

[0023] Step S3.2: Remove part of the anterior tooth area of ​​the orthodontic appliance and connect the upper and lower orthodontic appliance base models in an arc-shaped structure by removing the part of the appliance components.

[0024] Step S3.3: Thicken the occlusal surface of the posterior orthodontic appliance to form a magnet placement seat, and form a magnet mounting groove on the magnet placement seat for installing orthodontic magnets and adjusting the angle of the repulsive surfaces.

[0025] As a preferred embodiment of the present invention, in step S3.2, when constructing the arc-shaped body, a hole is reserved in the middle of the arc-shaped body for the treatment end of the negative pressure device to pass through.

[0026] As a preferred embodiment of the present invention, in step S4, the muscle force is applied using surface load in the software, the periodontal ligament is modeled using a viscoelastic model in the software, and the jawbone is modeled using a non-uniform mechanical property elastic model calculated based on CT grayscale values ​​in the software. The stress distribution and strain of the teeth, periodontium, and joint under different repulsive forces are simulated to obtain the results.

[0027] As a preferred embodiment of the present invention, in step S5, based on the optimal mandibular anterior displacement force obtained in step 4, the length of the orthodontic magnet is L, the thickness is t, and the vertical distance between the opposing surfaces of the two orthodontic magnets is d. The total projection of the two orthodontic magnets plus the gap in the vertical direction must satisfy: (2t+d)cosα+Lsinα≤Nmm, where N is the height space between the upper posterior tooth treatment area and the lower posterior tooth treatment area, and α is the angle between the direction of the mandibular anterior displacement force and the horizontal plane.

[0028] Compared to existing technologies, this method divides the main body of the orthodontic appliance into anterior and posterior sections. The anterior appliance has pre-drilled holes combined with a negative pressure device to move the tongue forward, expanding the upper airway space and improving ventilation. The posterior appliance incorporates magnets inside the appliance. By adjusting the angle of the repulsive surfaces and the magnitude of the magnetic force, the stress distribution on the dentition is altered. Biomechanical simulation calculations based on the stomatognathic system are performed to obtain the optimal magnitude and direction of the magnetic force. This provides a biomechanical basis for obtaining more precise magnetic force, thus avoiding clinical complications such as changes in occlusion and temporomandibular joint disorders, and ensuring the accuracy and safety of the forward movement force.

[0029] At the same time, under the traction of the mandible forward and downward by the orthodontic appliance in the posterior teeth area, the fulcrum of force is shifted from the anterior teeth (central incisors, lateral incisors, canines) to the posterior teeth (molar area, with robust tooth structure and strong periodontal tolerance). The leverage force is greatly reduced, and the anterior teeth no longer act as the fulcrum of force. This allows the tongue and masticatory muscles to always want to pull the mandible backward during sleep, and under the repulsive force of the posterior teeth, the repulsive force continues to counteract the retraction force forward. The anterior teeth baffle does not need to directly contact the retraction force. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the present invention;

[0031] Figure 2 This is a structural diagram of the upper and lower orthodontic appliances;

[0032] Figure 3 This is a schematic diagram showing the combination of the anterior orthodontic appliance and the negative pressure device.

[0033] Figure 4This is a schematic diagram of the structure of a posterior orthodontic appliance;

[0034] Reference numerals: 1. Main body of the orthodontic appliance; 2. Upper orthodontic appliance; 3. Lower orthodontic appliance; 31. Hole; 4. Anterior region orthodontic appliance; 5. Posterior region orthodontic appliance; 51. Upper posterior region orthodontic area; 52. Lower posterior region orthodontic area; 6. Magnet placement seat; 7. Magnet mounting slot; 8. Orthodontic magnet; 9. Negative pressure device. Detailed Implementation

[0035] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0036] like Figures 1-4 As shown, a magnetically driven, zoned mandibular and tongue-moving orthodontic appliance includes an appliance body 1 formed by combining an upper appliance 2 and a lower appliance 3. The appliance body 1 includes an anterior orthodontic appliance 4 that uses negative pressure to move the tongue forward to improve ventilation and a posterior orthodontic appliance 5 that uses magnetic force to provide mandibular forward movement. The anterior orthodontic appliance 4 includes an arc-shaped body 3 for preventing mouth breathing. The arc-shaped body 3 connects the upper appliance 2 and the lower appliance 3 to form an integrated structure. The orthodontic appliance body 1 is constructed; the posterior tooth appliance 5 includes an upper posterior tooth treatment area 51 located in the upper appliance 2 and a lower posterior tooth treatment area 52 located in the lower appliance 3. The upper posterior tooth treatment area 51 and the lower posterior tooth treatment area 52 are arranged opposite to each other, and orthodontic magnets 8 that form like poles and generate repulsive forces are installed in the upper posterior tooth treatment area 51 and the lower posterior tooth treatment area 52; the upper posterior tooth treatment area 51 and the lower posterior tooth treatment area 52 are formed with magnet mounting grooves 7 for adjusting the angle of the repulsive surfaces.

[0037] The upper appliance 2 and the lower appliance 3 are designed independently based on the patient's oral data. Under the action of the arc-shaped body 3, the upper appliance 2 and the lower appliance 3 are connected to form an integrated appliance body 1. The anterior tooth appliance 4 is set to correspond to the positions of the central incisors, lateral incisors, and canines. The posterior tooth appliance 5 is set to correspond to the positions of the first premolar to the third molar. The anterior tooth appliance 4 and the posterior tooth appliance 5 are connected at the distal proximal surface of the canines.

[0038] With the arc-shaped body 3 connecting the upper and lower orthodontic appliances 2 and 3 in the anterior tooth area, a gap is formed between the upper posterior tooth treatment area 51 and the lower posterior tooth treatment area 52 under the support of the arc-shaped body 3. The orthodontic magnet 8 is placed in this gap. Under the action of the upper posterior tooth treatment area 51 and the lower posterior tooth treatment area 52 that generate mutual repulsion, the mandible is moved forward and downward by the generated repulsion force, and the repulsion force provides support for the mandible.

[0039] With the 5 appliances in the posterior region pulling the mandible forward and downward, the fulcrum of force shifts from the anterior teeth (central incisors, lateral incisors, and canines) to the posterior teeth (molar region, with robust teeth and strong periodontal tolerance). The leverage force is greatly reduced, and the anterior teeth no longer act as the fulcrum of force. This allows the tongue and masticatory muscles to always try to pull the mandible backward during sleep, and under the repulsive force of the posterior teeth, the repulsive force continues to counteract the retraction force. The anterior tooth baffle does not need to directly contact the retraction force.

[0040] The arc-shaped body 3 has a hole 31 in the middle for the treatment end of the negative pressure device to pass through. The hole 31 is the size of the treatment end of the negative pressure device 9 to pass through. The negative pressure is used to move the tongue forward, expand the upper airway space, and further improve the ventilation effect.

[0041] The posterior orthodontic appliance 5 has a magnet holder 6 for loading the orthodontic magnet 8. The magnet holder 6 is formed on the occlusal surface of the posterior orthodontic appliance 5. The magnet mounting groove 7 is formed on the surface of the magnet holder 6. The orthodontic magnet 8 is embedded in the magnet mounting groove 7.

[0042] By installing the orthodontic magnet 8 on the occlusal surface of the posterior orthodontic appliance 5, and setting the orthodontic magnet 8 at an angle relative to the horizontal plane, an inclined repulsive force is generated between the upper posterior orthodontic area 51 and the lower posterior orthodontic area 52. The inclined repulsive force can be decomposed into a vertical component and a horizontal forward component. The upper repulsive force of the vertical component pushes the upper posterior orthodontic area 51 and the lower repulsive force presses down the lower posterior orthodontic area 52, opening the occlusal space in the posterior teeth. The horizontal forward component pushes the mandible forward along the mesiodistal direction of the crown. Without the hard clamp of the anterior orthodontic appliance 4 to fix the position of the mandible, the horizontal forward component that maintains the protrusion is borne by the repulsive force of the posterior occlusal surface. The force on the anterior teeth is greatly reduced, changing from a pressure fulcrum to a limiting auxiliary.

[0043] The orthodontic magnet 8 embedded in the upper posterior teeth orthodontic area 51 has a trapezoidal structure with its size gradually decreasing from top to bottom, and the orthodontic magnet 8 embedded in the lower posterior teeth orthodontic area 52 has a trapezoidal structure with its size gradually increasing from top to bottom.

[0044] The orthodontic magnet 8 adopts a trapezoidal structure with narrow facing ends and a wide base, which limits the contact points on the narrow mating surfaces, preventing the upper and lower orthodontic magnets 8 from slipping or misaligning towards the cheeks and tongue.

[0045] At the same time, the orthodontic magnet 8 gradually thickens and widens from the contact surface of the upper posterior tooth treatment area 51 or the lower posterior tooth treatment area 52, so that the occlusal impact force and magnetic repulsion force of the posterior teeth are transmitted downward. The force-bearing area of ​​the upper posterior tooth treatment area 51 or the lower posterior tooth treatment area 52 gradually increases and is dispersed in stages, and the unit pressure decreases. This avoids local stress concentration of small magnets, which may cause cracking of the upper posterior tooth treatment area 51 or the lower posterior tooth treatment area 52 or delamination of the orthodontic magnet 8, and greatly improves the service life of the orthodontic appliance.

[0046] A method for fabricating a magnetically driven, segmented mandibular and lingual advancement appliance, comprising the following steps:

[0047] Step S1: Three-dimensional reconstruction of the oral and maxillofacial model. Obtain intraoral scan data of the patient and obtain a three-dimensional model of the oral and maxillofacial system with the jawbone system and dental arch model based on the data.

[0048] The system acquires three types of data from the patient: CT, MRI, and intraoral scans. The CT / MRI image data is then processed using software such as Mimics to set thresholds, perform region growth, and optimize the reconstruction of the jawbone system and dental arch model. This model is then matched with the intraoral scan dental arch model to obtain a three-dimensional model of the jawbone system, which is saved as a triangular facet file.

[0049] Step S2: Construct the base model of the orthodontic appliance. Based on the dental arch model, prepare the base models of the upper orthodontic appliance 2 and the lower orthodontic appliance 3 to fit the dental arch.

[0050] The dental arch model is imported into a triangular surface processing software such as Geomagic, where smoothing operations such as relaxation are performed. The tooth surfaces are offset outward by 1mm, then shelled by 1mm, and finally surface-shaping is performed to create a 1mm thick base model for the upper appliance 2 and the lower appliance 3, which perfectly fit the dental arch.

[0051] Step S3: Structural design of the main body 1 of the orthodontic appliance. The base models of the upper orthodontic appliance 2 and the lower orthodontic appliance 3 are assembled in the software to a suitable forward and downward position, and an arc-shaped body 3 is constructed to connect the base models of the upper orthodontic appliance 2 and the lower orthodontic appliance 3 to form the main body 1 of the orthodontic appliance.

[0052] Step S3.1: Divide the main body of the orthodontic appliance 1 into anterior region appliance 4 and posterior region appliance 5, using the distal proximal surface of the canines as the boundary. Import the base models of the upper appliance 2 and the lower appliance 3 into 3D CAD software such as Solidworks, assemble them to the appropriate anterior and inferior position, remove part of the tooth area, and divide the main body of the orthodontic appliance 1 into anterior region appliance 4 and posterior region appliance 5.

[0053] Step S3.2: Remove part of the anterior tooth area of ​​the orthodontic appliance 4, and connect the base model of the upper appliance 2 and the base model of the lower appliance 3 to the arc-shaped body 3 in the removed part of the tooth area.

[0054] The arc-shaped body 3 is made of resin as a supporting structure. The one-piece design makes the forward and downward displacement more stable and prevents mouth breathing. The smooth arc surface makes the inner side of the lip contact with the main body 1 of the orthodontic appliance smoothly and comfortably.

[0055] Step S3.3: Thicken the occlusal surface of the posterior tooth appliance 5 to form a magnet placement seat 6, and form a magnet mounting groove 7 on the magnet placement seat 6 for installing the orthodontic magnet 8 and adjusting the angle of the repulsive surface.

[0056] The posterior orthodontic appliance 5, used as a force-applying structure, is made of silicone to improve comfort. The occlusal surfaces of the posterior orthodontic appliance 5 are thickened to a certain height to accommodate magnet placement seats 6. The orthodontic magnets 8 are medical-grade neodymium iron boron magnets. The orthodontic magnets 8 are trapezoidal in shape, with the upper base being the N pole and the lower base being the S pole.

[0057] The N pole of the orthodontic magnet 8 installed in the upper posterior teeth treatment area 51 faces downward, while the N pole of the orthodontic magnet 8 installed in the lower posterior teeth treatment area 52 faces upward. The orthodontic magnets 8 installed in the upper posterior teeth treatment area 51 and the lower posterior teeth treatment area 52, being of the same pole, generate a repulsive force when they face each other.

[0058] The installation of the orthodontic magnet 8 forms a certain angle with the horizontal plane, which generates an inclined repulsive force between the upper posterior tooth treatment area 51 and the lower posterior tooth treatment area 52. The inclined repulsive force can be decomposed into a vertical component and a horizontal forward component. The vertical component has an upward repulsive force pushing the upper posterior tooth treatment area 51 and a downward repulsive force pressing down the lower posterior tooth treatment area 52, opening the occlusal space in the posterior tooth area. The horizontal forward component follows the mesiodistal direction of the crown, continuously pushing the mandible forward as a whole.

[0059] In step S3.2, when constructing the arc-shaped body 3, a hole 31 is reserved in the middle of the arc-shaped body 3 for the treatment end of the negative pressure device to pass through. The hole 31 is the right size for the treatment end of the negative pressure device 9 to pass through. The negative pressure is used to move the tongue forward, expand the upper airway space, and further improve the ventilation effect.

[0060] Step S4: Stress analysis of the stomatognathic system. Construct a biomechanical model of the stomatognathic system based on muscle force, consisting of the mandible, tooth roots and periodontal ligament, temporomandibular joint and articular disc. Based on the periodontal ligament bone-promoting strain threshold and the articular disc deformation threshold, obtain the optimal mandibular forward movement force and magnetic force based on the stress threshold of the stomatognathic system.

[0061] The muscle force was applied using surface load in the software, the periodontal ligament was modeled using the viscoelastic model in the software, and the jawbone was modeled using a non-uniform mechanical property elastic model calculated based on CT grayscale values ​​in the software. The simulation was used to obtain the stress distribution and strain of the teeth, periodontium, and joint under different repulsive forces.

[0062] Step S5: Determine the size and placement angle of the corrective magnet 8 according to the required magnetic force.

[0063] Let F1 be the optimal mandibular anterior movement force obtained from step 4. This mandibular anterior movement force is provided by two sets of repulsive orthodontic magnets 8 in the left and right posterior tooth areas. Each set contains one maxillary orthodontic magnet 8 and one mandibular orthodontic magnet 8. The repulsion force required by each set is F per set = F1 / 2. The two orthodontic magnets 8 in each set (one maxillary and one mandibular) need to be installed together in a total space. This space is the posterior tooth occlusal space between the maxillary posterior tooth orthodontic area 51 and the mandibular posterior tooth orthodontic area 52.

[0064] The dimensions of the space formed by the occlusal gap in the posterior tooth region are set to be ≤12 mm in length, ≤4 mm in width, and ≤4 mm in height. These dimensions are derived from measurements of the upper posterior tooth orthodontic area 51 and the lower posterior tooth orthodontic area 52. They are a conservative estimate of the space where the orthodontic magnet 8 can be installed, with a certain amount of redundancy reserved.

[0065] Two orthodontic magnets 8 are placed vertically opposite each other, using an inverted trapezoidal prism shape. The upper base (smaller area) of the orthodontic magnet 8 is exposed on the occlusal surface, while the lower base (larger area) is embedded inside the upper posterior tooth treatment area 51 or the lower posterior tooth treatment area 52. The working surface of the orthodontic magnet 8 is an inclined plane, with an angle α between the inclined plane and the horizontal plane. The angle θ between α and the resultant force direction (mandibular anterior movement force direction) and the horizontal plane satisfies α = 90°-θ. Based on clinical experience and biomechanical principles, the angle θ between the resultant force direction and the horizontal plane is usually taken as 15°~30°, therefore the value of α is in the range of 60°~75°.

[0066] Let the length of the orthodontic magnet 8 be L, the thickness be t, and the vertical distance between the opposing surfaces of the two orthodontic magnets 8 be d. The total projection of the two orthodontic magnets 8 plus the gap in the vertical direction must satisfy: (2t+d)cosα+Lsinα≤Nmm, where N is the height space between the upper posterior tooth orthodontic area 51 and the lower posterior tooth orthodontic area 52, and α is the angle between the direction of the mandibular anterior movement force and the horizontal plane.

[0067] Lsinα originates from the vertical component of the length of the corrective magnet 8 (due to the inclination of the inclined plane, there is a height difference between the front and rear ends of the corrective magnet 8). Since α is relatively large (60°~75°), sinα is relatively large (0.866~0.966), while cosα is relatively small (0.259~0.5). This means that the length L contributes significantly to the vertical height, and the size of L needs to be strictly controlled, while the vertical projection contributions of the thickness t and the spacing d are relatively small.

[0068] Specifically, N48 type medical neodymium iron boron magnets are selected. Based on the above geometric constraints, the magnet length L typically needs to be ≤4 mm to avoid exceeding the height limit (specific calculations require iteration), the width ≤4 mm, and the thickness t can be 0.8~1.5 mm. Typical specifications and their repulsion force range at a normal spacing d = 1 mm are shown in the table below. Note: The repulsion force in the table corresponds to the normal spacing (the vertical distance between the two inclined planes), as shown in the figure below: 3×2×1.0 0.3 ~ 0.5 ≤ 0.5 4×2×1.2 0.6 ~ 0.8 0.5 ~ 0.8 4×3×1.5 0.9 ~ 1.2 0.8 ~ 1.2 5×4×1.5 1.3 ~ 1.7 1.2 ~ 1.7 6×4×1.5 1.8 ~ 2.2 1.7 ~ 2.2 .

[0069] For the magnet size finally selected in this design (3 mm × 4 mm × 1.2 mm, N48), based on the theoretical correction of the area ratio and thickness saturation factor, the repulsion force-normal spacing relationship is obtained as shown in the table below.

[0070] 0.5 3.6 1.0 3.2 1.5 2.06 2.0 1.41 2.5 1.03 3.0 0.77 .

[0071] In the example, the patient's mandibular forward displacement force F1 = 4.22 N, so F1 per group = 2.11 N. An N48 type inverted trapezoidal prism magnet with dimensions of 3 mm (length) × 4 mm (width) × 1.2 mm (thickness) is selected, with a slope angle α = 75° and a normal spacing d = 1.5 mm. Referring to the table above, the rejection force is approximately 2.06 N, which meets the design requirements. The geometric constraint is checked: (2 × 1.2 + 1.5) × cos75° + 3 × sin75° = 3.9 × 0.259 + 3 × 0.966 = 1.010 + 2.898 = 3.908 mm ≤ 4 mm, which meets the space constraints.

[0072] Step S6: Preparation of the main body 1 of the orthodontic appliance. The corresponding mold is printed using 3D printing technology. The main body 1 of the orthodontic appliance is formed by hot pressing of the mold, and the orthodontic magnet 8 is installed into the magnet placement seat 6.

[0073] The model of the thermoforming mold for the main body 1 of the orthodontic appliance was built using Solidworks software. The mold was printed using processes such as SLM. The mold was then installed and fixed on a press. The material was heated to the phase transition temperature and the shape and structure of the main body 1 of the orthodontic appliance were formed in one thermoforming process. Medical neodymium iron boron magnets were then attached to the main body 1 of the orthodontic appliance using adhesive.

[0074] After the orthodontic appliance is thermoformed, the processed inverted trapezoidal prism magnet is fixed with adhesive to the reserved positions in the upper posterior tooth treatment area 51 and the lower posterior tooth treatment area 52. The inverted trapezoidal structure of the orthodontic magnet 8 provides mechanical interlocking to prevent it from falling off.

[0075] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention; therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0076] Although this document uses numerous reference numerals from the figures, such as: appliance body 1, upper appliance 2, lower appliance 3, cavity 31, anterior region appliance 4, posterior region appliance 5, upper posterior region 51, lower posterior region 52, magnet holder 6, magnet mounting slot 7, orthodontic magnet 8, negative pressure device 9, etc., the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of the invention; interpreting them as any additional limitation would contradict the spirit of the invention.

Claims

1. A magnetically driven, partitioned mandibular and lingual advancement orthodontic appliance, comprising an appliance body (1) formed by combining an upper appliance (2) and a lower appliance (3); characterized in that, The main body of the orthodontic appliance (1) includes an anterior orthodontic appliance (4) that uses negative pressure to move the tongue forward to improve ventilation and a posterior orthodontic appliance (5) that uses magnetic force to provide mandibular forward movement. The anterior orthodontic appliance (4) includes an arc-shaped body (3) for preventing mouth breathing. The arc-shaped body (3) connects the upper orthodontic appliance (2) and the lower orthodontic appliance (3) to form an integrated orthodontic appliance body (1). The posterior orthodontic appliance (5) includes a component located on the upper orthodontic appliance (2). The upper posterior tooth orthodontic area (51) and the lower posterior tooth orthodontic area (52) located in the lower orthodontic appliance (3) are arranged opposite to each other, and orthodontic magnets (8) that form the same pole and generate repulsive force are installed in the upper posterior tooth orthodontic area (51) and the lower posterior tooth orthodontic area (52); the upper posterior tooth orthodontic area (51) and the lower posterior tooth orthodontic area (52) are formed with magnet mounting grooves (7) for adjusting the angle of the repulsive surface.

2. The magnetically driven, zoned mandibular and lingual advancement appliance according to claim 1, characterized in that, The arc-shaped body (3) has a hole (31) in the middle for the treatment end of the negative pressure device to pass through.

3. The magnetically driven, zoned mandibular and lingual advancement appliance according to claim 1, characterized in that, The posterior orthodontic appliance (5) has a magnet holder (6) for mounting orthodontic magnets (8), and the magnet holder (6) is formed on the occlusal surface of the posterior orthodontic appliance (5).

4. The magnetically driven, zoned mandibular and lingual advancement appliance according to claim 3, characterized in that, The magnet mounting groove (7) is formed on the surface of the magnet placement seat (6), and the corrective magnet (8) is embedded in the magnet mounting groove (7).

5. A magnetically driven, zoned mandibular and lingual advancement appliance according to claim 3, characterized in that, The orthodontic magnet (8) embedded in the upper posterior teeth orthodontic area (51) has a trapezoidal structure with the size gradually decreasing from top to bottom, and the orthodontic magnet (8) embedded in the lower posterior teeth orthodontic area (52) has a trapezoidal structure with the size gradually increasing from top to bottom.

6. A method for fabricating a magnetically driven, segmented mandibular and lingual advancement orthodontic appliance, based on any one of claims 1-5, characterized in that, Includes the following steps: Step S1: Three-dimensional reconstruction of the oral and maxillofacial model. Acquire intraoral scan data of the patient and obtain a three-dimensional model of the oral and maxillofacial system with the jawbone system and dental arch model based on the data. Step S2: Construct the base model of the orthodontic appliance, and prepare the base model of the upper orthodontic appliance (2) and the base model of the lower orthodontic appliance (3) to fit the dentition based on the dental arch model; Step S3: Orthodontic appliance body (1) structural design, assemble the upper orthodontic appliance (2) base model and the lower orthodontic appliance (3) base model in the software to the appropriate forward and downward position, and construct an arc-shaped body (3) connect the upper orthodontic appliance (2) base model and the lower orthodontic appliance (3) base model to form the orthodontic appliance body (1). Step S4: Stress analysis of the stomatognathic system. Construct a biomechanical model of the stomatognathic system based on muscle force, consisting of the mandible, tooth roots and periodontal ligament, temporomandibular joint and articular disc. Based on the periodontal ligament bone-promoting strain threshold and the articular disc deformation threshold, obtain the optimal mandibular forward movement force and magnetic force based on the stress threshold of the stomatognathic system. Step S5: Determine the size and placement angle of the corrective magnet (8) according to the required magnetic force; Step S6: Preparation of the main body (1) of the orthodontic appliance. The corresponding mold is printed using 3D printing technology. The main body (1) of the orthodontic appliance is formed by hot pressing of the mold, and the orthodontic magnet (8) is installed into the magnet placement seat (6).

7. The method for preparing a magnetically driven, zoned mandibular and lingual advancement orthodontic appliance according to claim 6, characterized in that, Step S3 further includes the following sub-steps: Step S3.1: Divide the main body of the orthodontic appliance (1) into anterior region appliance (4) and posterior region appliance (5) with the distal proximal surface of the canine as the boundary; Step S3.2: Remove part of the anterior tooth area of ​​the orthodontic appliance (4), and connect the base model of the upper appliance (2) and the base model of the lower appliance (3) to the arc-shaped body (3) in the part of the removed tooth area. Step S3.3: Thicken the occlusal surface of the posterior orthodontic appliance (5) to form a magnet placement seat (6), and form a magnet mounting groove (7) on the magnet placement seat (6) for installing the orthodontic magnet (8) and adjusting the angle of the repulsive surface.

8. The method for preparing a magnetically driven, zoned mandibular and lingual advancement orthodontic appliance according to claim 7, characterized in that, In step S3.2, when constructing the arc-shaped body (3), a hole (31) is reserved in the middle of the arc-shaped body (3) for the treatment end of the negative pressure device to pass through.

9. The method for preparing a magnetically driven, zoned mandibular and lingual advancement orthodontic appliance according to claim 6, characterized in that, In step S4, muscle force is applied using surface load in the software, periodontal ligament is modeled using the viscoelastic model in the software, and jawbone is modeled using the non-uniform mechanical property elastic model calculated based on CT grayscale values ​​in the software. The simulation obtains the stress distribution and strain of teeth, periodontium, and joints under different repulsive forces.

10. The method for preparing a magnetically driven, zoned mandibular and lingual advancement orthodontic appliance according to claim 6, characterized in that, In step S5, based on the optimal mandibular forward movement force obtained in step 4, let the length of the orthodontic magnet (8) be L, the thickness be t, and the vertical distance between the opposite surfaces of the two orthodontic magnets (8) be d. The total projection of the two orthodontic magnets (8) plus the gap in the vertical direction must satisfy: (2t+d)cosα+Lsinα≤Nmm, where N is the height space between the upper posterior tooth orthodontic area (51) and the lower posterior tooth orthodontic area (52), and α is the angle between the direction of the mandibular forward movement force and the horizontal plane.

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