Sandwich type auxiliary positioning device for micro-implant assisted maxillary rapid expansion arch and manufacturing method of maxillary rapid expansion arch

Abstract

This invention provides a sandwich-type auxiliary positioning device for rapid maxillary expansion assisted by micro-implants, and a method for manufacturing the rapid maxillary expander. The device includes a base digitally designed according to the shape of a spiral expander, and a top cover that tightly engages with the base. This invention adjusts the relative position of the sandwich-type auxiliary device and the patient's maxilla in digital software to locate the position and drilling depth of the micro-implant, ensuring the spiral expander is in the ideal position. Later, 3D printing is used to print the patient's digital maxillary model and the base of the sandwich-type auxiliary device as a single unit. During the fabrication of the rapid maxillary expander, the top cover clamps and fixes the spiral expander to the base, transferring the precise digital positioning of the spiral expander and micro-implant to the 3D-printed model for technician processing. This ensures the fixation of the micro-implant to the palatal plate of the maxilla and prevents complications such as nasal mucosal damage.

Description

Technical Field

[0001] This invention relates to the precise positioning of a maxillary rapid expander, specifically to a sandwich-type auxiliary device for precise positioning of a maxillary rapid expander and a method for manufacturing the maxillary rapid expander. Background Technology

[0002] Micro-implant-assisted rapid palatal expansion (MARPE) is an orthodontic technique used to rapidly expand the maxillary palatal sutures to correct bony narrowing of the maxilla. A typical MARPE appliance consists of a spiral expander and four small micro-implants inserted through the gum line into the maxillary palatal bone plate, with the spiral expander mounted on the roof of the mouth. The micro-implants act as anchor points for the expander, and by rotating the spiral mechanism of the expander at a higher frequency, more efficient and effective palatal expansion is achieved.

[0003] Compared to traditional palatal expanders, the MARPE appliance has several advantages, including: 1. The micro-implant can directly apply expanding force to the palatal bones on both sides of the palatal suture, thus achieving more controllable and predictable expansion; 2. Compared to traditional expanders, MARPE treatment time is faster; 3. MARPE is relatively small, making it more comfortable for patients; 4. Compared to traditional expanders, the MARPE appliance has fewer side effects, such as significantly reducing molar tilting or root damage.

[0004] Because MARPE implants use micro-implants to penetrate the palatal mucosa and bone plate for retention, it is a somewhat invasive method. Therefore, the effectiveness of this method in achieving better results and reducing adverse side effects depends on the accurate positioning of the micro-implant and spiral expander. Insufficient implant length will affect MARPE retention, while excessive implant length can easily lead to damage to the nasal mucosa, causing symptoms such as nasal bleeding. Incorrect implant orientation may also damage the tooth root. Currently, there is no ideal method for positioning the micro-implant and spiral expander.

[0005] The rapid development of digital technology in orthodontics has recently changed some traditional workflows. The widespread clinical application of cone-beam computed tomography (CBCT), intraoral scanning / model scanning, and 3D printing technologies has made digital measurement and positioning of micro-implant-assisted maxillary rapid expansion devices possible. Two issues need to be addressed: 1. Precise positioning of the micro-implant in the palate; 2. Achieving stability of the palatal expander during the later fabrication process. Summary of the Invention

[0006] This invention provides a sandwich-type auxiliary positioning device for rapid maxillary expansion assisted by micro-implants. The rapid maxillary expander includes a spiral expander. The two sides of the spiral expander are connected to the band via connecting rods. The four corners of the spiral expander are fixedly connected to the maxillary bone plate via four micro-implants. The spiral expander and the band are fixedly connected via connecting rods after being positioned on a maxillary solid model outside the mouth.

[0007] The sandwich-type auxiliary device includes a detachable and snap-fit ​​positioning base and a top cover. The positioning base and the top cover are provided with a snap-fit ​​structure to keep them relatively fixed after being snapped together. The snap-fit ​​surfaces of the positioning base and the top cover are provided with positioning grooves that fit with the outer contour of the spiral expander.

[0008] In the digital 3D model of the patient's oral cavity, the relative position of the positioning base and the maxillary solid model is determined according to the position of the micro implant. The maxillary solid model and the positioning base are then formed in one piece using 3D printing.

[0009] Install the spiral amplifier onto the positioning base and fasten the top cover to clamp and fix the spiral amplifier. Place the custom-made strap around the teeth of the maxillary solid model and fix the spiral amplifier to the strap on both sides using the connecting rod.

[0010] Furthermore, there are buckles on both sides of the positioning base, and the positioning base is connected to the top cover buckle through the buckles. At the end of the buckle, there is an anti-detachment protrusion that is interference-fitted with the top cover.

[0011] Furthermore, the belt loop is made of metal, and the connecting rod is made of steel wire. The connecting rod is fixedly connected to the spiral amplifier and belt loop by welding.

[0012] Furthermore, the spiral expander has welding parts on both sides for welding connection with the connecting rod, and the sandwich-type auxiliary device has openings on both sides for exposing the welding parts.

[0013] A method for fabricating a micro-implant-assisted maxillary rapid expander based on the above-mentioned sandwich-type auxiliary positioning device, the method comprising the following steps:

[0014] S1. Obtain a digital 3D model of the patient's oral cavity;

[0015] S2. Fit the digital models of the micro-implants, spiral expanders, and sandwich-style auxiliary devices into the digital three-dimensional model of the oral cavity.

[0016] S3. Adjust the position of the sandwich-style auxiliary device digital model in the oral digital 3D model until the position of the micro implant is accurately located;

[0017] S4. Design of bands on both sides of the tooth contour based on the digital three-dimensional model of the oral cavity;

[0018] S5. Fit the digital model of the sandwich-type auxiliary device with the digital three-dimensional model of the oral cavity, and use 3D printing technology to print the maxillary solid model and the sandwich-type auxiliary device of the digital three-dimensional model of the oral cavity. The positioning base of the sandwich-type auxiliary device is integrally formed with the maxillary solid model, and the top cover is printed separately.

[0019] S6. Install the spiral amplifier into the positioning slot of the positioning base and fasten the top cover to clamp and fix the spiral amplifier. Place the metal rings made on both sides of the teeth of the maxillary solid model and fix the spiral amplifier to the rings on both sides through the connecting rod.

[0020] S7. Remove the top cover and take out the prepared maxillary rapid expander.

[0021] Furthermore, in step S1, after performing CBCT scanning and intraoral dental scanning, the CBCT scanning model is fitted with the intraoral dental scanning model to obtain a digital three-dimensional model of the patient's oral cavity.

[0022] Furthermore, in step S2, after the digital models of the micro implant, the spiral expander, and the sandwich-type auxiliary device are fitted, the spiral expander is located inside the sandwich-type auxiliary device that is fastened together, and the micro implant is located at the tightened position of the spiral expander.

[0023] Furthermore, in the digital 3D model of the oral cavity, each micro-implant penetrates the cortical bone of the palatal bone plate near the nasal cavity, and the height of the micro-implant tip protruding from the cortical bone is within 0.5mm.

[0024] The innovation of this invention lies in:

[0025] 1) After importing the 3D model of the sandwich-type assistive device into the digital 3D model of the patient's maxilla, the relative positions of the sandwich-type assistive device and the patient's maxilla are adjusted to ensure the implant is in the ideal position. The 3D model of the sandwich-type assistive device and the digital 3D model of the patient's maxilla are then fitted as a functional unit. Later, 3D printing is used to print the patient's maxilla and the base of the sandwich-type assistive device as a single unit. During the assembly of the maxillary rapid expander, the spiral expander is clamped and fixed to the base, ensuring its optimal installation position. This results in the final maxillary rapid expander being the most suitable shape for the patient. After installation in the mouth, the bands and wires on both sides provide positioning for the spiral expander, ensuring its position in the mouth matches its position in the digital model.

[0026] 2) Before printing, first locate the position and drilling depth of the micro implant in the model. Later, after fixing the spiral expander to the base of the solid model, install the micro implant in the current position, which is the ideal installation position in the patient's mouth. This improves the retention of the spiral expander while reducing damage to the patient. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of a rapid maxillary expander currently fabricated on a maxillary 3D model.

[0029] Figure 2 This is a schematic diagram of a digital three-dimensional model of the patient's oral cavity obtained by fitting a CBCT scan model with an intraoral dental scan model according to the present invention.

[0030] Figure 3 This is a schematic diagram showing the result of fitting the digital model of the sandwich-style assistive device with the digital 3D model of the oral cavity;

[0031] Figure 4 for Figure 2 Side view of the fitted digital model;

[0032] Figure 5 An electronic scan of a spiral expander after it has been fixed to the maxilla using micro-implants;

[0033] Figure 6 To design a schematic diagram of the loop in the digital model;

[0034] Figure 7 A schematic diagram showing the fitting of a digital model of a sandwich-style auxiliary device after precise positioning of micro-implants with a digital 3D model of the oral cavity;

[0035] Figure 8 A three-dimensional view of the positioning base for the sandwich-type auxiliary device;

[0036] Figure 9 A perspective view of the top cover of the sandwich-type auxiliary device;

[0037] Figure 10 A schematic diagram showing the positioning base and top cover of the sandwich-type auxiliary device being fastened together;

[0038] Figure 11 for Figure 10A magnified view of a portion of the image;

[0039] Figure 12 This is a schematic diagram of placing the spiral amplifier onto the positioning base;

[0040] Figure 13 This is a schematic diagram showing how the central spiral expander is held in place after the top cover of the positioning base is snapped together. Detailed Implementation

[0041] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0042] To fully understand this invention, detailed steps and structures will be presented in the following description to illustrate the technical solution of this invention. Preferred embodiments of the invention are described in detail below; however, in addition to these detailed descriptions, the invention may have other embodiments.

[0043] Figure 1 The image shows the completed fabrication of the current maxillary rapid expander 10. The fabrication method is as follows: a maxillary model is printed based on a template, and the band is custom-made. Then, the band 13 is placed on the teeth on both sides of the maxillary model. Finally, the two sides of the spiral expander 11 are connected to the band 13 using wire. However, this method has the following drawbacks: the spiral expander 11 lacks auxiliary positioning during installation, and the final fixed position is often not ideal. This also leads to the micro-implant being installed in an undesirable position, and the drilling depth of the micro-implant relies entirely on the dentist's experience; too deep or too shallow is unsuitable.

[0044] This invention provides a sandwich-type auxiliary positioning device for rapid maxillary expansion assisted by micro-implants. The rapid maxillary expander 10 includes a spiral expander 11, the two sides of which are welded to a metal band 13 via steel wire connecting rods 12. The four corners of the spiral expander 11 are fixedly connected to the maxillary bone plate by four micro-implants 14. After the spiral expander 11 and band 13 are positioned on a maxillary solid model 20 outside the mouth, they are fixedly connected by the connecting rods 12.

[0045] like Figure 8-13 As shown, the sandwich-type auxiliary device 30 includes a detachable, snap-fit ​​positioning base 31 and a top cover 32. When snapped together, the positioning base 31 and top cover 32 are used to clamp the spiral expander 11 in the middle. To ensure the stability of the snap-fit, the positioning base 31 and top cover 32 are provided with a snap-fit ​​structure to keep them relatively fixed after snapping. Figure 11As shown, buckles 31-1 are provided on both sides of the positioning base 31. The positioning base 31 is connected to the upper cover 32 by buckles 31-1, and an anti-dislodgement protrusion 31-2 with an interference fit to the upper cover 32 is provided at the end of the buckle 31-1. This structure realizes the detachable fastening connection between the positioning base 31 and the upper cover 32. When the upper cover 32 is fastened to the positioning base 31, the two are firmly connected, tightly holding the spiral expander 11 in the middle and preventing it from shifting. At the same time, after the maxillary rapid expander is manufactured, the upper cover 32 can be removed to take out the maxillary rapid expander.

[0046] Furthermore, a positioning groove 33 is provided on the fastening surface of the positioning base 31 and the upper cover 32, which fits against the outer contour of the spiral expander 11. After the positioning base 31 and the upper cover 32 are fastened together, the outer contour of the spiral expander 11 fits against the positioning groove 33 of the positioning base 31 and the upper cover 32, eliminating the gap between the positioning base 31, the upper cover 32 and the spiral expander 11, so that the spiral expander 11 and the sandwich-type auxiliary device 30 are firmly integrated into one unit. Since the positioning base 31 is integrally printed with the maxillary solid model 20, it means that after the positioning base 31 and the upper cover 32 are fastened together, the position of the spiral expander 11 in the middle is equivalent to the optimal installation position in the patient's mouth.

[0047] Please see Figures 2-7 The following is a further explanation of the method for fabricating a rapid maxillary expander based on the micro-implant 14 of the present invention.

[0048] Step S1: Obtain a digital 3D model of the patient's oral cavity. In this invention, the digital 3D model of the oral cavity is obtained by fitting a cone-beam computed tomography (CBCT) model and an intraoral scan / model scan model. The specific steps are: 1) Obtain data of the patient's intraoral soft and hard tissues through an intraoral CBCT scan and reconstruct the CBCT model in 3D; 2) Obtain 3D digital images of the patient's teeth and mucosal surface information through an intraoral 3D optical scan; 3) Accurately reconstruct the target tissue using the CBCT scan model combined with the 3D optical scan model. The final digital 3D model of the maxilla is shown below. Figure 2 As shown.

[0049] Step S2: Fit the digital models of the micro-implant 14, spiral expander 11, and sandwich-type auxiliary device 30 into the oral digital three-dimensional model. After fitting, the micro-implant 14, spiral expander 11, and sandwich-type auxiliary device 30 appear as an inseparable unit in the model. Figure 3As shown. It should be noted that the micro-implant 14, the spiral expander 11, and the sandwich-type auxiliary device 30 are all prefabricated components. Therefore, the digital models of these three components are readily available and can be directly imported into the digital 3D model of the oral cavity, or the corresponding parameters can be adjusted in the software and then fitted together before being imported into the digital 3D model of the oral cavity. Furthermore, in the digital model, the micro-implant 14 is in the fully tightened position of the spiral expander 11, meaning the micro-implant 14 cannot be tightened further. After the rapid expander is fabricated, the micro-implant 14 is tightened to its proper position, meaning the large end of the micro-implant 14 abuts against the through-hole end face of the spiral expander 11.

[0050] Step S3: Adjust the position of the sandwich-style auxiliary device digital model in the oral digital 3D model until the position of the micro implant 14 is precisely located. For example... Figures 4-5 As shown in the background art, it has been recorded that if the micro implant 14 is implanted too deeply, it will cause greater trauma to the patient, while if it is implanted too shallowly, it will not be able to retain the spiral expander 11. After comprehensive consideration, in the present invention, each micro implant 14 in the digital three-dimensional model of the oral cavity penetrates to the cortical bone 2 of the palatal bone plate 1 near the nasal cavity, and the tip of the micro implant 14 protrudes from the cortical bone by less than 0.5 mm, thereby improving the retention of the spiral expander 11 while reducing damage to the patient.

[0051] Step S4: Design the bands 13 on both sides of the teeth based on the tooth contour of the digital 3D model of the oral cavity. (For example...) Figure 6 As shown.

[0052] Step S5: Fit the digital model of the sandwich-type assistive device with the digital 3D model of the oral cavity. After fitting, the digital 3D model of the patient's maxilla and the digital model of the sandwich-type assistive device become an inseparable whole in the 3D model, such as... Figure 7 As shown. Subsequently, 3D printing technology was used to print the maxillary solid model 20 and the sandwich-type auxiliary device 30 of the oral cavity digital three-dimensional model. The positioning base 31 of the sandwich-type auxiliary device 30 was integrally formed with the maxillary solid model 20, while the top cover 32 needed to be printed separately.

[0053] Step S6: Install the spiral expander 11 into the positioning groove 33 of the positioning base 31 and fasten the top cover 32 to firmly fix the spiral expander 11 in the middle. Then, place the metal band 13 made on the teeth on both sides of the maxillary solid model 20. Finally, weld the spiral expander 11 and the band 13 together with steel wire to form the final maxillary rapid expander.

[0054] S7. Remove the top cover 32 and take out the prepared maxillary rapid expander.

[0055] The preferred embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and the devices and structures not described in detail should be understood as being implemented in a conventional manner in the art. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the present invention. This does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the present invention are still within the scope of protection of the present invention.

Claims

1. A sandwich auxiliary positioning device for micro-implant assisted rapid expansion of the upper jaw, the rapid expansion of the upper jaw device (10) comprising a spiral expander (11), the two sides of the spiral expander (11) being connected to a band ring (13) through a connecting rod (12), and the four corners of the spiral expander (11) being used for fixed connection with the upper jaw bone plate (1) through four micro-implants (14), the spiral expander (11) and the band ring (13) being fixedly connected through the connecting rod (12) after positioning on the upper jaw physical model (20) outside the mouth, characterized in that the sandwich auxiliary device (30) comprises a positioning base (31) and an upper cover (32) which can be detachably buckled together, the positioning base (31) and the upper cover (32) are provided with buckle structures for keeping the relative fixation after buckling, and the buckling surfaces of the positioning base (31) and the upper cover (32) are each provided with a positioning groove (33) which is fitted with the outer contour of the spiral expander (11); the relative positions of the positioning base (31) and the upper jaw physical model (20) are determined according to the positions of the micro-implants (14) which are positioned in the digital three-dimensional model of the patient's oral cavity, and the upper jaw physical model (20) and the positioning base (31) are integrally formed by 3D printing; after the spiral expander (11) is installed on the positioning base (31) and the upper cover (32) is buckled to clamp and fix the spiral expander (11), the customized band ring (13) is sleeved on the teeth of the upper jaw physical model (20), and the two sides of the spiral expander (11) and the band ring (13) are fixedly connected through the connecting rod (12). The positioning base (31) is provided with buckles (31-1) on the two sides, the positioning base (31) is buckled and connected with the upper cover (32) through the buckles (31-1), and the buckles (31-1) are provided with anti-disengagement protrusions (31-2) which are in interference fit with the upper cover (32) at the ends.

2. The sandwich type auxiliary positioning device for micro-implant assisted rapid expansion of the upper arch of claim 1, wherein, The band ring (13) is made of metal, the connecting rod (12) is made of steel wire, and the connecting rod (12) is fixedly connected with the spiral expander (11) and the band ring (13) by welding.

3. The sandwich type auxiliary positioning device for micro-implant assisted rapid expansion of the upper arch of claim 1, wherein, The two sides of the spiral expander (11) are provided with welding portions (11-1) for welding connection with the connecting rod (12), and the two sides of the sandwich auxiliary device (30) are provided with openings (34) for exposing the welding portions (11-1).

4. The sandwich type auxiliary positioning device for micro-implant assisted rapid expansion of the upper arch of claim 3, wherein, The manufacturing method comprises the following steps:

5. A method for making a micro-implant (14) assisted rapid maxillary expansion appliance based on the sandwiched auxiliary positioning device according to any one of claims 1-4, characterized in that, S1, obtaining an oral digital three-dimensional model of the patient's oral cavity; S2, fitting the digital models of the micro-implants (14), the spiral expander (11) and the sandwich auxiliary device (30) and importing them into the oral digital three-dimensional model, S3, adjusting the position of the digital model of the sandwich auxiliary device in the oral digital three-dimensional model until the position of the micro-implant (14) is accurately positioned; S4, designing the band ring (13) on both sides based on the tooth contour of the oral digital three-dimensional model. ​ S5, the sandwich auxiliary device digital model is fitted with the oral digital three-dimensional model, 3D printing technology is adopted to print the maxillary entity model (20) and the sandwich auxiliary device (30) of the oral digital three-dimensional model, wherein the positioning base (31) of the sandwich auxiliary device (30) is integrally formed with the maxillary entity model (20), and the upper cover (32) is separately printed and formed; S6, the spiral expander (11) is installed into the positioning groove (33) of the positioning base (31) and is buckled with the upper cover (32) to clamp and fix the spiral expander (11), the prepared ring (13) is sleeved at the teeth on both sides of the maxillary entity model (20), and the spiral expander (11) on both sides is fixedly connected with the ring (13) through the connecting rod (12); S7, the upper cover (32) is removed, and the prepared maxillary rapid expander is taken out.

6. The method of claim 5, wherein In step S1, after CBCT scanning and intraoral tooth scanning, the CBCT scanning model is fitted with the intraoral tooth scanning model to obtain the oral digital three-dimensional model of the patient's oral cavity.

7. The manufacturing method as described in claim 5, characterized in that, In step S2, after the digital models of the micro-implant (14), the spiral expander (11) and the sandwich auxiliary device are fitted, the spiral expander (11) is located in the sandwich auxiliary device buckled together, and the micro-implant (14) is located at the tightening position of the spiral expander (11).

8. The manufacturing method as described in claim 5, characterized in that, In step S3, each micro-implant (14) in the oral digital three-dimensional model penetrates to the bone cortex of the maxillary bone plate (1) near the nasal cavity side, and the height of the micro-implant (14) tip protruding from the bone cortex is within 0.5mm.

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