An improved spiral expander

Abstract

The present invention provides an improved spiral expander, wherein the spindle stud comprises a first threaded area, a second threaded area and a force application area; the pitches of the external threads of the first threaded area and the second threaded area are equal and opposite in direction, and the force application area drives the spindle stud to rotate under the action of an external force; there are two positioning nuts, which are symmetrically sleeved on the outside of the first threaded area and the second threaded area, and are provided with internal threads matching the external threads of the spindle stud; there are four adjustment arms of equal length, and the two sides of each positioning nut are respectively rotatably connected to one end of an adjustment arm; there are two external device connection points, which are symmetrically arranged on both sides of the spindle stud, and each external device connection point is respectively rotatably connected to the other end of a pair of adjustment arms on the same side. The expander provided by the present invention reduces the requirements for the patient's opening degree and the degree of fit, reduces the risk of the expansion adjustment piece falling off and swallowing by mistake, and can also prevent the teeth from moving unexpectedly during the expansion process, avoiding damage to oral tissues and periodontal tissues.

Description

Technical Field

[0001] The invention belongs to the technical field of oral medical instruments, and in particular relates to an improved spiral expander. Background Art

[0002] At present, the core structure of the spiral expander widely used at home and abroad is a main shaft stud and two sections of positioning nuts. The main shaft screw of the expander is parallel to the opening direction. When the main shaft stud is rotated toward the throat, the distance between the two sections of the positioning nuts increases. The positioning nuts are directly connected to the palate bones through implants or are connected to the teeth through metal brackets, plastic bases, etc., thereby increasing the width of the mid-palatal suture or the width of the dental arch, thereby achieving the purpose of orthodontic clinical expansion.

[0003] In actual clinical operation, this type of spiral expander is installed in the child's mouth with the main shaft stud and the mid-palatal suture perpendicular to each other. During expansion, the parent needs to push the expansion adjustment piece (expansion wrench or expansion key) toward the throat in the child's mouth. The operation position is relatively far back, which places greater demands on the child's opening degree and cooperation. In addition, the expansion adjustment piece is not easy to pull out when it is close to the throat due to the angle problem, and there is a risk of it falling and being swallowed accidentally after being pulled out.

[0004] Chinese patent CN216535564U discloses a maxillary bone-supported bony arch expansion device, in which the threaded rod 7 of the arch expansion device can be placed in the oral cavity in a direction parallel to the mid-palatal suture, and the relative movement of the locking nut 8 on the threaded rod 7 drives the fixtures 5 on both sides to expand outward, thereby achieving the arch expansion effect. However, the arch expansion device has the following defects:

[0005] First, the outward expansion of the retainer 5 is controlled by adjusting the locking nut 8 to make it close to the fixed end of the hinge shaft 2, and there is an inconvenience in rotating the locking nut in the oral cavity;

[0006] Secondly, during the adjustment process, only the side of the hinge shaft 2 close to the locking nut 8 moves, and the side away from the locking nut 8 remains stationary, resulting in the widening of the two side fixators 5 in the direction perpendicular to the mid-palatal suture and displacement in the direction parallel to the mid-palatal suture. The range of movement of the fixators is large, and the surrounding oral tissues are easily damaged during the movement.

[0007] Thirdly, in clinical practice, the fixator needs to be bonded in the mouth through implant pins or metal brackets or plastic bases, so that the widening force of the fixator can be transmitted to the mouth. Therefore, the fixator is required to be well fixed in the mouth. However, under this design, in addition to the widening force, the fixator will also generate force in the direction of movement of the hinge axis 2. The latter not only has an adverse effect on the stability of the fixator, making the fixator more likely to loosen and fall off, affecting the clinical effect, but may also have an adverse effect on the teeth used for fixation, causing unwanted mesial movement of the teeth and periodontal damage.

[0008] Based on this, it is a technical problem that urgently needs to be solved to provide an improved expander that improves the convenience of expander adjustment and reduces the damage to oral tissue and periodontal tissue caused by the movement of the fixator while reducing the difficulty of expander operation and the risk of accidental swallowing of the expander adjusting parts. Summary of the invention

[0009] The purpose of the present invention is to address the deficiencies of the prior art and provide an improved spiral expander with a simple structure, convenient operation, reduced risk of accidental swallowing of the expansion adjusting member (wrench or key), and reduced damage to oral tissue and periodontal tissue during movement of the fixator.

[0010] In order to solve the above technical problems, the present invention adopts the following technical solutions: providing an improved spiral expander, comprising a main shaft stud, a positioning nut, an adjustment arm and an external device connection;

[0011] The spindle stud comprises a first threaded area and a second threaded area, and a first force application area located therebetween; the pitches of the external threads of the first threaded area and the second threaded area are equal and opposite in direction; the first force application area drives the spindle stud to rotate under the action of an external force;

[0012] There are two positioning nuts, which are symmetrically sleeved outside the first threaded area and the second threaded area; the positioning nuts are provided with internal threads matching the external threads of the spindle stud;

[0013] There are four adjusting arms of equal length, and both sides of the positioning nut are rotatably connected to one end of an adjusting arm respectively;

[0014] There are two external device connection points, which are symmetrically arranged on both sides of the main shaft stud and are used for fixed connection with the external device; each of the external device connection points is rotatably connected to the other end of a pair of adjustment arms on the same side.

[0015] On the basis of the above technical solution, the first force application area includes a cylindrical ring fixed on the main shaft stud, and the cylindrical ring is evenly provided with a plurality of adjustment holes along the circumferential direction.

[0016] On the basis of the above technical solution, the first force application area includes a clamping portion fixed on the spindle stud, and the cross-section of the clamping portion is a regular polygon.

[0017] On the basis of the above technical solution, the spindle stud further includes a second force application area, and the second force application area is arranged on a side of the first threaded area away from the first force application area.

[0018] Based on the above technical solution, both ends of the spindle stud are rounded and blunt.

[0019] On the basis of the above technical solution, the positioning nut includes a positioning nut body and first hinged parts located on both sides thereof, the first hinged part can accommodate the end of the adjusting arm and is provided with a first hinged hole.

[0020] On the basis of the above technical solution, second hinge holes matching the first hinge holes are formed at both ends of the adjusting arm.

[0021] On the basis of the above technical solution, a second hinge part is provided at both ends of the connection of the external device, the second hinge part can accommodate the end of the adjustment arm, and a third hinge hole matching the second hinge hole is opened.

[0022] On the basis of the above technical solution, the external device connection of the improved spiral expander is connected to the palate bone through an implant screw.

[0023] On the basis of the above technical solution, the external device connection of the improved spiral expander is connected to the teeth through a metal bracket or a plastic base.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The improved spiral expander provided by the present invention has a main shaft stud that can be placed in a direction parallel to the mid-palatal suture, thereby changing the rotation direction of the expansion wrench. During the adjustment process, it is not necessary to go deep into the throat direction. The main shaft stud can be driven to rotate by swinging the wrench horizontally to achieve expansion adjustment, thereby reducing the requirements for the child's opening degree and coordination, and also reducing the risk of the wrench falling and being swallowed accidentally during the expansion process.

[0026] (2) The improved spiral expander provided by the present invention rotates the main shaft screw to make the symmetrically arranged positioning nuts move relative to each other along the first threaded area and the second threaded area with opposite thread directions, and then drive the adjustment arm connected thereto to move, thereby realizing the change of the relative distance of the external device connection, and achieving the purpose of expanding the arch. Since the two positioning nuts are symmetrically arranged, the pitch of the first threaded area and the second threaded area is equal, and the lengths of the four adjustment arms are equal, during the adjustment process, the two external device connections only produce displacement in the direction perpendicular to the mid-palatal suture, and their projected position at the center point of the main shaft stud does not change, thereby avoiding unnecessary movement during the use of the expander and causing unexpected movement of the teeth, and also reducing the risk of damage to the soft tissue in the oral cavity caused by the displacement of the expander. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the overall structure of an improved spiral expander provided by an embodiment of the present invention;

[0028] Figure 2 A side view of an improved spiral expander provided by an embodiment of the present invention;

[0029] Figure 3 A top view of an improved spiral expander provided by an embodiment of the present invention;

[0030] Figure 4 A schematic structural diagram of a first spindle stud provided in an embodiment of the present invention;

[0031] Figure 5 A schematic structural diagram of a second spindle stud provided in an embodiment of the present invention;

[0032] Figure 6 A schematic structural diagram of a third type of spindle stud provided in an embodiment of the present invention;

[0033] Figure 7 A top view of a positioning nut provided in an embodiment of the present invention;

[0034] Figure 8 A schematic diagram of the structure of an adjustment arm provided in an embodiment of the present invention;

[0035] Fig. 9 A side view of a connection portion of an external device provided by an embodiment of the present invention;

[0036] Fig.10 A schematic diagram of a connection method of the improved spiral expander provided in an embodiment of the present invention.

[0037] Among them, 1-spindle stud; 11-first threaded area; 12-second threaded area; 13-first force application area; 14-cylindrical ring; 15-adjustment hole; 16-clamping part; 17-second force application area; 2-positioning nut; 21-positioning nut body; 22-first hinged part; 23-first hinged hole; 3-adjusting arm; 31-second hinged hole; 4-external device connection; 41-second hinged part; 42-third hinged hole. DETAILED DESCRIPTION

[0038] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0040] The present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited thereto.

[0041] Example

[0042] See also Figure 1-3 , this embodiment provides an improved spiral expander, which includes a spindle stud 1, a positioning nut 2, an adjustment arm 3 and an external device connection 4;

[0043] The spindle stud 1 includes a first threaded area 11 and a second threaded area 12, and a first force application area 13 located therebetween; the pitches of the external threads of the first threaded area 11 and the second threaded area 12 are equal and in opposite directions; the first force application area 13 drives the spindle stud 1 to rotate under the action of external force; there are two positioning nuts 2, which are symmetrically sleeved on the outside of the first threaded area 11 and the second threaded area 12; the positioning nuts 2 are provided with internal threads matching the external threads of the spindle stud 1; there are four adjusting arms 3 of equal length, and the two sides of the positioning nuts 2 are respectively rotatably connected to one end of an adjusting arm 3; there are two external device connection points 4, which are symmetrically arranged on both sides of the spindle stud 1 for fixed connection with an external device; each of the external device connection points 4 is respectively rotatably connected to the other end of a pair of adjusting arms 3 on the same side.

[0044] In this embodiment, when the operator uses the expansion adjustment member (such as an expansion key or an expansion wrench) to adjust the first force application area 13 of the spindle stud 1, the first force application area 13 is subjected to external force and drives the spindle stud 1 to rotate accordingly, and produces relative movement with the positioning nut 2. Since the external threads of the first threaded area 11 and the second threaded area 12 on the upper part of the spindle stud 1 are in opposite directions, the directions of relative movement of the upper and lower positioning nuts 2 are also opposite, that is, they move toward the force application area 13 at the same time or move away from the first force application area 13 at the same time. When the distance between the two positioning nuts 2 is reduced, the adjustment arm 3 connected thereto and the end connected to the external device connection 4 are forced to move in the direction away from the spindle stud, thereby increasing the distance between the two external device connections 4, thereby achieving the effect of expanding the bow. After expanding the bow, the expansion adjustment member is swung in the opposite direction to achieve the effect of contracting the bow.

[0045] In the present invention, by means of the adjustment arm 3 connected to the positioning nut 2 and the external device connection 4, the movement of the positioning nut 2 in a direction parallel to the palatal suture is converted into the movement of the external device connection 4 in a direction perpendicular to the palatal suture, so that the main shaft stud 1 can be placed in a direction parallel to the palatal suture. On the one hand, when the main shaft stud 1 is parallel to the palatal suture, the expansion adjustment member matched with the first force application area 13 can drive the main shaft stud 1 to rotate as long as it swings horizontally in the oral cavity. Compared with the conventional rotation method of pushing the expansion wrench or key to the throat, this embodiment can reduce the risk of swallowing the expansion adjustment member by mistake and reduce the requirements for the degree of opening. On the other hand, patients with narrow dental arch bones often have clinical manifestations of high palate arches and the palate shape is not flat enough. Compared with traditional expansion devices, the expander of the present invention can be closer to the top of the upper palate and closer to the source of resistance, and better clinical effects can be obtained. In addition, due to the proximity to the upper palate, the gap between the expander and the upper palate is reduced, which is not easy to cause food residues, and can also reduce the adverse effects of the use of the expander on the patient's oral hygiene.

[0046] Furthermore, for the external device connections 4 on both sides of the spindle stud 1, since the distances from the two positioning nuts 2 to the force application area 13 are equal, the pitches of the external threads of the first threaded area 11 and the second threaded area 12 are equal, and the lengths of the four adjustment arms 3 are also the same, when the two positioning nuts 2 move synchronously, the two external device connections 4 only produce displacement in the direction perpendicular to the mid-palatal suture, and their projection positions at the center point of the spindle stud 1 remain unchanged. The external device connections 4 always open to both sides on the same straight line, avoiding unnecessary movement of the external device connections 4 during the use of the expander to cause tooth movement, and reducing the risk of damage to the soft tissue in the oral cavity caused by displacement of the expander.

[0047] In this embodiment, the spindle stud 1 can be divided into three areas according to the different structures of the threads, the top is the first threaded area 11, the middle is the first force application area 13, and the bottom is the second threaded area 12. The external thread of the first threaded area 11 is a left-handed thread, and the external thread of the second threaded area 12 is a right-handed thread, and the pitch of the external threads is equal. With such a thread arrangement, when the expander is fixed to the upper palate in a manner that the first threaded area 11 is close to the incisor, the method of turning the wrench toward the right side of the teeth can bring about the effect of reducing the relative distance of the positioning nut 2, making it easier for the operator to perform the expansion operation.

[0048] Preferably, the length range of the spindle stud 1 is 12 to 28 mm, and the diameter range is 2 to 6 mm; the length range of the force application area 13 is 2 to 4 mm.

[0049] Figure 4A schematic diagram of the structure of the first force application area 13 of the spindle stud 1 is provided. The first force application area 13 is not provided with an external thread, but is provided with a cylindrical ring 14 fixed to the middle of the spindle stud 1. The cylindrical ring 14 is evenly provided with a plurality of adjustment holes 15 along the circumferential direction. Preferably, the number of the adjustment holes 15 is eight, and they are connected in pairs along the diameter direction of the cross section of the spindle stud 1. The structure of the first force application area 13 can use an expansion key as an expansion adjustment member. The expansion key is inserted into the adjustment hole 15, and the expansion key is rotated horizontally to complete the expansion operation.

[0050] Figure 5 Another structural schematic diagram of the first force application area 13 of the spindle stud 1 is provided, wherein the first force application area 13 includes a clamping portion 16 fixed to the spindle stud 1, and the cross section of the clamping portion 16 is a regular polygon. Preferably, the cross section of the clamping portion 16 is a regular octagon. The structure of the first force application area 13 can use an expansion wrench as an expansion adjustment member, and the expansion wrench is clamped to the clamping portion 16, and the expansion operation can be completed by applying a lateral rotational external force.

[0051] Figure 6 A schematic diagram of a more preferred structure of a spindle stud 1 is provided. Based on the above structure of the spindle stud 1, the spindle stud 1 further includes a second force application area 17, which is arranged on the side of the first threaded area 11 away from the first force application area 13 and is placed toward the outside of the oral cavity. In the case where the patient's mouth opening is small, by adjusting the second force application area 17, the operation of rotating the spindle stud 1 can be completed at a position closer to the outside of the mouth. The structure of the second force application area 17 is similar to that of the first force application area 13, and can be a cylindrical ring with an adjustment hole or a regular polygonal clamping portion, or other structures that are convenient for force application can be selected.

[0052] Furthermore, the two ends of the main shaft stud 1 are rounded and blunt. Such a structural design can reduce the foreign body sensation caused by the use of the expander, protect the soft tissue in the oral cavity, and avoid accidental damage.

[0053] See also Figure 7 The positioning nut 2 includes a positioning nut body 21 and first hinged parts 22 located on both sides thereof. The first hinged parts 22 can accommodate the ends of the adjusting arm 3 and are provided with first hinged holes 23. Specifically, the first hinged parts 22 are two horizontal short arms extending from both sides of the positioning nut body 21, which are used to clamp the ends of the adjusting arm 3. Holes are opened on the horizontal short arms and the ends of the adjusting arm 3, and small bolts are used to pass through and fix them, forming a freely rotatable joint.

[0054] See also Figure 8The two ends of the adjusting arm 3 are provided with second hinge holes 31 matching the first hinge holes 23. For ease of operation, when the expander is installed in the oral cavity and is in the initial state, the angle between the adjusting arm 3 and the main shaft stud 1 is preferably controlled at 15-30°.

[0055] See also Fig. 9 , the two ends of the external device connection 4 are provided with second hinged parts 41, the second hinged parts 41 can accommodate the ends of the adjustment arm 3, and are provided with third hinged holes 42 matching the second hinged holes 31. Specifically, the second hinged parts 41 are two horizontal short arms extending from both ends of the external device connection, which are used to clamp the ends of the adjustment arm 3, and holes are opened on the ends of the horizontal short arms and the adjustment arm 3, and small bolts are used to pass through and fix them, forming a joint that can rotate freely.

[0056] In this embodiment, the specific shape of the external device connection part 4 is not limited. Specifically, it can be designed according to the application scenario. For example, if it is connected to the palate through an implant screw, the external device connection part 4 is a rectangular parallelepiped with two holes; if it is connected to the tooth through a plastic base, the external device connection part 4 is thinner in the center and extends outward in a thin sheet shape, embedded in the center of the plastic base, with only the horizontal short arm at the end exposed.

[0057] See also Fig.10 , which shows a schematic diagram of an application of the improved spiral expander provided in this embodiment, wherein the external device connection of the improved spiral expander is connected to the teeth by welding a metal bracket and using a metal belt ring. In addition, the external device connection of the improved spiral expander can also be fixed by connecting it to the palate bone through an implant screw, or connecting it to the teeth through a plastic base, etc., which is not limited here.

[0058] In the present invention, since the positioning nut 2 is connected to the adjusting arms 3 on both sides, the adjusting arms 3 are connected to the external device 4, and the external device 4 is fixed to the teeth or palate bones, this fixing form makes the positioning nut 2 not rotate with the rotation of the main shaft stud 1, and can only produce relative up and down movement, thereby causing the external device 4 to open laterally.

[0059] The method of using the improved spiral expander provided in this embodiment is as follows:

[0060] First, according to the actual situation of the patient, the external device connection 4 of the expander is directly connected to the palate bone through an implant screw or connected to the teeth through a metal bracket, a plastic base. During the fixed installation, the main shaft screw 1 of the expander is parallel to the midpalatal suture of the child, and the left-handed thread area is close to the incisor.

[0061] When the arch expansion operation is required, the wrench is stuck in the force application area (taking the arch expansion wrench as an arch expansion adjustment part as an example), and the wrench is turned in the direction of the right teeth, driving the spindle stud 1 to rotate in the direction of the right teeth. The upper positioning nut 2 is screwed downward due to the effect of the left-handed thread, and the lower positioning nut 2 is screwed upward due to the effect of the right-handed thread. The distance between the two positioning nuts 2 is symmetrically reduced, forcing the ends of the adjustment arm 3 connected to the external device connection 4 to move symmetrically away from the spindle stud 1 (i.e., in the direction of opening the mid-palatal suture), thereby increasing the distance between the two external device connections to achieve arch expansion. After the arch expansion is completed, resin can be added near the two positioning nuts 2. After the resin is cured, the positioning nuts 2 and the nearby structure are connected as one, thereby achieving the closure of the arch expander and maintaining the arch expansion effect.

[0062] Furthermore, when it is necessary to perform a bow retraction operation, the wrench is stuck in the force application area, and the wrench is rotated in the direction of the left teeth, driving the spindle stud 1 to rotate in the direction of the left teeth, and the upper positioning nut 2 is screwed upward due to the action of the left-handed thread, and the lower positioning nut 2 is screwed downward due to the action of the right-handed thread. The distance between the two positioning nuts 2 increases symmetrically, forcing the ends of the adjustment arm 3 connected to the external device connection 4 to move symmetrically in the direction close to the spindle stud 1 (i.e., in the direction of narrowing the mid-palatal suture), thereby narrowing the distance between the two external device connections to achieve bow retraction.

[0063] During the above operation, no matter it is arch expansion or arch retraction, since the movements of the positioning nuts 2 and the adjustment arms 3 on both sides are symmetrical, the external device connection 4 only moves in the direction perpendicular to the mid-palatal suture and does not move in the direction parallel to the mid-palatal suture, and its projection position at the center point of the main shaft stud 1 remains unchanged, thereby preventing the external device connection 4 from causing unexpected movement of the teeth during the use of the expander and reducing the risk of damage to the soft tissue in the oral cavity caused by displacement of the expander.

[0064] The above are only preferred embodiments of the present invention, and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the contents of the specification of the present invention should be included in the protection scope of the present invention.

Claims

1. An improved spiral expander, characterized in that: It comprises a spindle stud (1), a positioning nut (2), an adjustment arm (3) and an external device connection (4); The spindle stud (1) comprises a first threaded area (11) and a second threaded area (12), and a first force application area (13) located therebetween; the pitches of the external threads of the first threaded area (11) and the second threaded area (12) are equal and opposite in direction; the first force application area (13) drives the spindle stud (1) to rotate under the action of an external force; There are two positioning nuts (2), which are symmetrically sleeved outside the first threaded area (11) and the second threaded area (12); the positioning nuts (2) are provided with internal threads matching the external threads of the spindle stud (1); There are four adjusting arms (3) of equal length, and both sides of the positioning nut (2) are rotatably connected to one end of an adjusting arm (3) respectively; There are two external device connection points (4), which are symmetrically arranged on both sides of the main shaft stud (1) and are used for fixed connection with the external device; each of the external device connection points (4) is rotatably connected to the other end of a pair of adjustment arms (3) on the same side.

2. The improved spiral expander according to claim 1, characterized in that: The first force application area (13) comprises a cylindrical ring (14) fixed on the main shaft stud (1), and the cylindrical ring (14) is evenly provided with a plurality of adjustment holes (15) along the circumferential direction.

3. The improved spiral expander according to claim 1, characterized in that: The first force application area (13) comprises a clamping portion (16) fixed on the spindle stud (1), and the cross section of the clamping portion (16) is a regular polygon.

4. The improved spiral expander according to claim 2 or 3, characterized in that: The spindle stud (1) further comprises a second force application area (17), wherein the second force application area (17) is arranged on a side of the first threaded area (11) away from the first force application area (13).

5. The improved spiral expander according to claim 4, characterized in that: Both ends of the main shaft stud (1) are round and blunt.

6. The improved spiral expander according to claim 1, characterized in that: The positioning nut (2) comprises a positioning nut body (21) and first hinged parts (22) located on both sides thereof. The first hinged parts (22) can accommodate the ends of the adjustment arms (3) and are provided with first hinged holes (23).

7. The improved spiral expander according to claim 6, characterized in that: Second hinge holes (31) matching the first hinge holes (23) are formed at both ends of the adjusting arm (3).

8. The improved spiral expander according to claim 7, characterized in that: The two ends of the external device connection part (4) are provided with second hinged parts (41), the second hinged parts (41) can accommodate the end of the adjustment arm (3), and are provided with third hinged holes (42) matching with the second hinged holes (31).

9. The improved spiral expander according to any one of claims 1 to 8, characterized in that: The external device connection part (4) of the improved spiral expander is connected to the palate bone via an implant screw.

10. The improved spiral expander according to any one of claims 1 to 8, characterized in that: The external device connection part (4) of the improved spiral expander is connected to the teeth through a metal bracket or a plastic base.

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