Primary-secondary type bone anchorage nail and anchorage assembly and manufacturing method thereof

Abstract

The application discloses a mother-son type bone anchorage nail, which comprises a mother nail and a son nail. The mother nail is a self-tapping screw, and the son nail is a non-self-tapping screw. The son nail and the mother nail are detachably connected through threads. An anchorage accessory is also provided, which can be sleeved on the periphery of the platform of the mother nail and has an anchorage arm extending outward to sleeve a target to be fixed. The mother-son type bone anchorage nail is a prefabricated part, and the anchorage accessory is a 3D printed part made according to a patient's oral model. The implantation position of the bone anchorage nail is in the median palatine suture, and the bone anchorage nail is used in combination with the anchorage accessory, so that accurate positioning and convenient replacement can be realized, the use amount of the anchorage nail is reduced, the harm to the patient is reduced, multiple teeth can be simultaneously moved, the efficiency is improved, and the treatment course is shortened.

Description

Technical Field

[0001] This invention relates to the field of orthodontics, and more particularly to a mother-daughter type bone anchorage screw, anchorage assembly, and its manufacturing method. Background Technology

[0002] In orthodontic treatment, tooth movement under force is a crucial part of the process. However, the force applied during orthodontic treatment is always accompanied by an equal but opposite reaction force. This introduces the concept of anchorage, which is a structure that can resist or counteract the reaction force of the orthodontic force. Teeth are commonly used as anchorage in orthodontics. However, regardless of the type of tooth, movement will occur under force. Therefore, we need to utilize other methods for effective anchorage control to achieve favorable and desired tooth movement, and to prevent unfavorable and unwanted tooth movement.

[0003] Distal molar movement has become the primary orthodontic method using clear aligners (invisible braces). During molar distalization with invisible braces, the more teeth moved simultaneously, the higher the anchorage requirements. Better anchorage control is often needed in this case; therefore, in clinical practice, implant anchorage, such as bone anchorage screws, is frequently used in conjunction with molar distalization.

[0004] However, existing bone anchorage screws have some problems: First, the main implantation site of the anchorage screw is the alveolar bone between the tooth roots, which can easily damage the tooth roots during implantation. Second, when pushing molars distally, implanting screws between the tooth roots can hinder the movement of the tooth roots. Therefore, the method of repositioning the screws multiple times is usually adopted to prevent obstruction. However, multiple repositioning will prolong the treatment process and cause more harm to the patient.

[0005] Therefore, those skilled in the art are dedicated to developing an orthodontic bone anchorage nail that can avoid multiple nail repositioning and has strong support. Summary of the Invention

[0006] In view of the above-mentioned deficiencies of the prior art, the present invention provides a mother-daughter type bone anchorage screw, which includes a mother screw and a daughter screw; wherein, the mother screw is a self-tapping screw, which includes a first external thread section, a first smooth section and a platform in sequence along the axial direction, the end face of the platform has a first groove for screwing, and the platform end of the mother screw has a daughter screw receiving space extending inward along the axial direction, the side wall of the receiving space has an internal thread; the daughter screw is a non-self-tapping screw, which includes a second external thread section, a second smooth section and a screw head in sequence along the axial direction, the second external thread of the second external thread section matches the internal thread of the mother screw, and the end face of the screw head has a second groove for screwing; the daughter screw and the mother screw are detachably connected by the internal thread and the second external thread, and the bottom surface of the screw head is larger than the end face of the platform.

[0007] Furthermore, the bottom surface of the nail head refers to the surface opposite to the mother nail after the male and female nails are connected. The radial length of this bottom surface is greater than the radial length of the end face of the mother nail platform, so that it can completely cover and extend beyond the platform.

[0008] Preferably, the female nail and the male nail are coaxially connected.

[0009] Preferably, the female screw is a pointed screw and the female screw is a flat-head screw.

[0010] Preferably, the depth of the first groove at the platform end of the female nail is the same as the axial length of the second smooth section of the male nail. In this way, after the two are connected, the platform end face of the female nail and the bottom surface of the nail head of the male nail abut against each other, which can better fix them together.

[0011] Preferably, the radial cross-section of the platform is polygonal, and more preferably pentagonal or hexagonal.

[0012] Preferably, the first groove is a cross-shaped groove.

[0013] Preferably, the second groove is also a cross-shaped groove; more preferably, the second groove has the same shape and size as the first groove.

[0014] Preferably, the distance from the bottom surface of the sub-nailing space to the end face of the platform is greater than or equal to the length of the sub-nailing excluding the nail head.

[0015] Preferably, the radial length of the bottom surface of the daughter nail head is 1.0-3.0 mm longer than the radial length of the end surface of the mother nail platform, and more preferably 2.0-2.5 mm longer.

[0016] Preferably, the first external thread section is further provided with a chip removal groove; the chip removal groove is used to contain bone fragments and tissue debris during the implantation process, so that these fragments will not affect the implantation effect due to accumulation on the implantation channel; the first external thread section may also be provided with an overflow channel that leads directly to the platform, for further discharge of bone fragments and tissue debris.

[0017] Preferably, the implantation site of the mother-daughter type bone anchorage nail is the maxilla, and more preferably, the implantation site is the mid-palatal suture.

[0018] Preferably, the ratio of the axial length of the first external thread segment to the axial length of the first smooth segment is 1.8-2.2:1, for example, 2:1; in a preferred embodiment of the present invention, the axial length of the first external thread segment is 4.5-6.5 mm, preferably 5.8-6.2 mm, and the axial length of the first smooth segment is 2.2-3.5 mm, preferably 2.9-3.1 mm.

[0019] Preferably, the axial length of the platform is 1.8-2.2 mm.

[0020] Preferably, the axial length of the nail head is 1.0-2.0 mm, and the axial length of the sub-nails excluding the nail head is 1.6-2.2 mm.

[0021] Preferably, the depth of the first groove and the second groove is less than 1 mm.

[0022] Preferably, the total axial length of the mother-daughter type bone anchorage nail is 6-14 mm, and more preferably 10-14 mm.

[0023] Preferably, the maximum radial length of the first external thread section and the radial length of the first smooth section are 2.2-3.4 mm, and more preferably 2.4-3.2 mm.

[0024] Preferably, the radial length of the second external thread section and the second smooth section is 1.0-2.2 mm, and more preferably 1.4-2.0 mm.

[0025] Preferably, the radial length of the platform is 3.6-5.6 mm, and more preferably 4.0-5.2 mm.

[0026] Preferably, the radial length of the nail head is 4.2-6.6 mm, and more preferably 5.0-6.0 mm.

[0027] Furthermore, the mother nail is used for intraosseous implantation, and the daughter nail is used for fixing the anchorage accessory.

[0028] Furthermore, the present invention provides an anchorage attachment for the mother-daughter type bone anchorage nail. The anchorage attachment includes a circumferential structure and at least one outwardly extending anchorage arm. The circumferential structure has a through hole in the center, the radial profile of which is the same as the radial outer profile of the platform, allowing the circumferential structure to be fitted around the platform. The proximal end of the anchorage arm is connected to the circumferential structure, and the distal end has a collar for securing the target to be fixed. This anchorage attachment is secured by the nail head bottom surface, which is larger than the platform end face, as described above, preventing it from dislodging.

[0029] Preferably, the bracing accessory is a 3D printed part.

[0030] Preferably, the radial profile of the through hole is polygonal, more preferably pentagonal or hexagonal, which makes the circumferential structure less prone to rotation and displacement.

[0031] Preferably, the axial length of the circumferential structure is less than or equal to the axial length of the platform, and most preferably, the two are equal.

[0032] Preferably, the number of support arms is two or more, and more preferably two to four.

[0033] Preferably, the sidewall thickness of the circumferential structure is 0.8-2.0 mm.

[0034] Preferably, the support arm is cylindrical, and its diameter is preferably 0.6-1.2 mm.

[0035] In some preferred embodiments of the present invention, the implantation site of the mother-daughter type bone anchorage nail is the mid-palatal suture, and the anchorage arm has an arc-shaped structure that can closely fit the palatal arch.

[0036] Preferably, the ring is further provided with hooks, protrusions or clips for securing invisible braces.

[0037] Furthermore, the present invention also provides an anchorage assembly including the mother-daughter type bone anchorage nail and the anchorage accessory; wherein the mother-daughter type bone anchorage nail is a prefabricated part, and the anchorage accessory is a 3D printed part made according to a patient's oral cavity model.

[0038] Preferably, the oral cavity model is obtained after the implantation of the mother-daughter bone anchorage screw, so that the specific parameters of the anchorage arm can be accurately determined according to the specific implantation location of the bone anchorage screw.

[0039] Furthermore, the present invention also provides a method for manufacturing the above-mentioned anchorage attachments or anchorage components, comprising the following steps:

[0040] 1) Precast mother-and-child type bone anchorage nail;

[0041] 2) The bone anchorage nail was implanted into the patient's mid-palatal suture;

[0042] 3) Obtain the patient's oral cavity model;

[0043] 4) Fabricate anchorage attachments based on the shape, distance, and curvature parameters in the patient's oral model.

[0044] Preferably, the anchorage attachment is manufactured by 3D printing.

[0045] The orthodontic micro-anchorage screw of the present invention has the following beneficial technical effects:

[0046] 1) The anchorage screw of the present invention is implanted in the mid-palatal suture, where the gingiva is relatively thin, making implantation convenient and safe, and it can also be used by adolescents;

[0047] 2) The female and male screws are detachable and can be used in conjunction with 3D-printed anchor arms. During clinical treatment, when pushing the molars backward, the canine rod (canine anchor arm) is used; after the posterior teeth are in place, the molar rod (molar anchor arm) is replaced to assist in the retraction of the anterior teeth. This avoids multiple screw repositioning, reduces the number of screws used, and also reduces harm to the patient.

[0048] 3) It strengthens the anchorage and supports the simultaneous movement of multiple teeth, which improves efficiency and shortens the treatment course.

[0049] The following will further explain the concept, specific structure, and technical effects of the present invention in conjunction with the accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the mother-daughter type bone anchorage nail of the present invention;

[0051] Figure 2 This is a schematic diagram of the structure of an embodiment of the sub-nail of the present invention;

[0052] Figure 3 This is a schematic diagram of the platform end face structure of an embodiment of the mother nail of the present invention;

[0053] Figure 4 This is a schematic diagram of the nail head end face structure of an embodiment of the present invention;

[0054] Figure 5 This is a schematic diagram of the internal structure of the platform after the male and female nails of the present invention are connected;

[0055] Figure 6 This is a schematic diagram of the structure of an embodiment of the present invention combining a mother-daughter type bone anchorage nail and anchorage accessories;

[0056] Figure 7 This is a schematic diagram illustrating the application of the anchorage component of the present invention in anchoring canines during molar pushing;

[0057] Figure 8 This is a schematic diagram illustrating the application of the anchorage component of the present invention in anchoring molars during the retraction of anterior teeth. Detailed Implementation

[0058] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0059] like Figure 1 and Figure 2 As shown, in a preferred embodiment of the present invention, the mother-daughter type bone anchorage screw includes a mother screw 1 and a daughter screw 2. The mother screw 1 is a self-tapping screw, and from bottom to top in the figure, it includes a first external thread section 11, a first smooth section 12, and a platform 13. The daughter screw 2 is a non-self-tapping screw, and is a flat-head screw, and from bottom to top, it includes a second external thread section 21, a second smooth section 22, and a screw head 23; wherein the bottom surface 231 of the screw head 23 is larger than the end surface 131 of the platform 13. The lower end of the mother screw 1 also has a chip removal groove 15.

[0060] The length L1 of the first external thread section 11 is 6 mm, the length L2 of the first smooth section 12 is 3 mm, and the length L3 of the platform 13 is 2 mm. The length L4 of the nail head 23 is 1.8 mm, and the length of the female nail 2 excluding the nail head is also 1.8 mm. The maximum diameter of the female nail 1 excluding the platform 13 is 3 mm, and the maximum diameter of the female nail 2 excluding the nail head 23 is 1.5 mm.

[0061] like Figures 3 to 5 As shown, the end face of the platform 13 has a first groove 14 for screwing, and the platform end of the female nail 1 has a female nail receiving space 16 extending axially inward, which is located below the first groove 14 (the first groove 14 and the receiving space 16 are connected, therefore...). Figure 3 The cross-shaped groove shown only shows four ends, its sidewall has an internal thread 161, and below the internal thread 161 there is a smooth sidewall 162; the second external thread of the second external thread section 21 matches the internal thread 161 of the female nail, and the end face of the nail head 23 has a second groove 24 for screwing, by screwing the male nail 2 and the female nail 1 can be connected.

[0062] The first groove 14 and the second groove 24 are both cross-shaped and the same size. The depth of the first groove 14 is the same as the length of the second smooth section 22 of the male nail 2. When they are connected, the platform end face 131 of the female nail 1 and the bottom face 231 of the nail head of the male nail 2 abut against each other, allowing for better fixation. The radial cross-section of the platform 13 is hexagonal, so the female nail 1 can be tightened with both a Phillips head screwdriver and an Allen head screwdriver. Furthermore, the diagonal length of the cross-section of the platform 13 is 5 mm.

[0063] Figure 6 The diagram shows a preferred embodiment of the anchorage attachment of the present invention combined with a mother-daughter type bone anchorage nail. The anchorage attachment 3 includes a circumferential structure 31 and two outwardly extending anchorage arms 32, the number of which can be selected according to actual needs. Figure 5Two supports are shown. The proximal end of the support arm 32 is connected to the circumferential structure 31, and the distal end has a collar 33 that can be fitted around the tooth to be fixed. The collar 33 may also have protrusions 34 for fixing the invisible aligner. The circumferential structure 31 has a through hole in the middle, and its structure is the same as the outer contour of the platform 13 of the mother pin 1, allowing the circumferential structure 31 to fit around the platform 13. The support attachment 3 is held in place by the bottom surface 231 of the pin head, which is larger than the platform end face, and will not come out. The outer contour of the circumferential structure 31 can be hexagonal like the inner contour, or it can be circular. If its outer contour is also hexagonal, the sidewall thickness can be 1.5 mm, the total diagonal length is 8 mm, and the diameter of the bottom surface 231 of the pin head 23 can be 6 mm. The support arm 32 is an arc-shaped structure that can closely conform to the shape of the palatal arch. The support arm 32 is cylindrical with a diameter of 1 mm. Furthermore, in this embodiment, the mother-daughter type bone anchorage nail is a prefabricated component, and the anchorage accessory 3 is a 3D printed component made based on the patient's oral cavity model.

[0064] Figure 7 and Figure 8 This illustrates a preferred embodiment of the invention for retracting anterior teeth during clinical treatment. The fabrication, implantation, and fixation process of the anchorage component can be briefly described as follows:

[0065] 1) The mother screw and daughter screw of the prefabricated mother-daughter type bone anchorage nail;

[0066] 2) Use a Phillips screwdriver to insert the female nail into the patient's mid-palatal suture, and then use a Phillips screwdriver to screw the female nail into the female nail;

[0067] 3) Create a plaster model of the patient's oral cavity (including a mother-daughter bone anchorage screw);

[0068] 4) Based on the shape, distance, and curvature parameters in the patient's oral plaster model, use 3D printing to fabricate anchorage attachments for the two canines (the third from the middle) on the left and right sides; the anchorage attachments include an encircling structure 31, two anchorage arms 32, two rings 33, and protrusions 34 are also provided on the outer side of the rings;

[0069] 5) Unscrew the pin from the patient's mouth;

[0070] 6) Place the collar 33 of the support attachment onto the canine, and place the circumferential structure 31 around the platform of the mother nail;

[0071] 7) Re-screw in the sub-screws to secure the support accessories via the screw heads;

[0072] 8) Place the invisible braces used to push the four molars behind the teeth onto the teeth, where the protrusions 34 on the rings help to hang the braces.

[0073] 9) After the molars are in place, remove the dental braces and anchorage attachments, and recreate the patient's oral model using plaster.

[0074] 10) Based on the shape, distance, and curvature parameters in the new oral model, use 3D printing to fabricate anchorage attachments for the two second molars (sixth from the middle); the anchorage attachments also include a circumferential structure 31, two anchorage arms 32, two rings 33, and a protrusion 34;

[0075] 11) The invisible braces used to retract the anterior teeth are put on the teeth, wherein the protrusions 34 on the rings help to suspend the braces;

[0076] 12) After the anterior teeth have retracted, remove the braces and anchorage attachments, and unscrew the male and female screws.

[0077] The above orthodontic process uses two different anchorage attachments, but there is no need to re-implant anchorage screws. The original anchorage attachments can be removed and replaced with new ones, which avoids the damage of multiple implantations and saves on the amount of anchorage screws used.

[0078] The anchorage assembly of the mother-daughter type bone anchorage nail of the present invention is easy to implant, firmly fixed, and flexible to replace or move, reducing the amount of nails used, reducing harm to patients, and shortening the treatment course.

[0079] In the description of this invention, it should be understood that the terms "middle," "length," "thickness," "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0080] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0081] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A method for manufacturing an anchorage assembly comprising a mother-daughter type bone anchorage nail and anchorage accessories, characterized in that, Includes the following steps: 1) Prefabrication of the aforementioned mother-and-child type bone anchorage nail: The device includes a female screw and a male screw. The female screw is a self-tapping screw, which includes, along the axial direction, a first external thread segment, a first smooth segment, and a platform. The end face of the platform has a first groove for screwing, and the platform end of the female screw has a male screw receiving space extending inward along the axial direction. The side wall of the male screw receiving space has an internal thread. The male screw is a non-self-tapping screw, which includes, along the axial direction, a second external thread segment, a second smooth segment, and a screw head. The second external thread of the second external thread segment matches the internal thread of the female screw, and the end face of the screw head has a second groove for screwing. The male screw and the female screw are detachably connected by the internal thread and the second external thread, and the bottom surface of the screw head is larger than the end face of the platform. 2) The mother-daughter type bone anchorage nail is implanted into the mid-palatal suture of the patient's maxilla; 3) Obtain the patient's oral cavity model; 4) Fabricate the anchorage attachments based on the shape, distance, and curvature parameters in the patient's oral model: It includes a circumferential structure and two or more outwardly extending support arms. The circumferential structure has a through hole in the middle, and the radial contour of the through hole is the same as the radial outer contour of the platform, so that the circumferential structure can be fitted around the periphery of the platform. The proximal end of each support arm is connected to the circumferential structure, and the distal end has a collar that can fit around the target to be fixed. The collar is also provided with a protrusion for fixing invisible dental braces.

2. The method for manufacturing an anchorage assembly comprising a mother-daughter type bone anchorage nail and anchorage accessories as described in claim 1, characterized in that, The radial length of the bottom surface of the female nail head is 1.0-3.0 mm longer than the radial length of the end face of the female nail platform. The ratio of the axial length of the first external thread section to the first smooth section is 1.8-2.2:

1. The axial length of the platform is 1.8-2.2 mm. The axial length of the nail head is 1.0-2.0 mm. The axial length of the female nail excluding the nail head is 1.6-2.2 mm. The depth of the first groove and the second groove is less than 1 mm. The total axial length of the male-female bone anchorage nail is 6-14 mm. The maximum radial length of the first external thread section and the radial length of the first smooth section are 2.2-3.4 mm. The radial lengths of the second external thread section and the second smooth section are 1.0-2.2 mm. The radial length of the platform is 3.6-5.6 mm. The radial length of the nail head is 4.2-6.6 mm.

3. The method for manufacturing an anchorage assembly comprising a mother-daughter type bone anchorage nail and anchorage accessories as described in claim 1, characterized in that, The sidewall thickness of the circumferential structure is 0.8-2.0 mm.

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