Jaw bone tractor

Abstract

The utility model relates to a jawbone tractor, which comprises a traction tube which is provided with a guide groove and is provided with a front end and a rear end; the fixed traction plate is fixed relative to the traction tube; the movable traction seat is restrained in the guide groove and can axially slide, and a threaded through hole which axially penetrates through the movable traction seat is formed in the movable traction seat; the movable traction plate is fixed on the movable traction seat; the traction screw rod is arranged in the guide groove and can rotate around the axis of the traction screw rod, the front end of the traction screw rod penetrates out of the traction pipe to form a driving end, the universal joint is used for being connected with the stress application rod, and the traction screw rod penetrates through and is in threaded connection with the interior of a threaded through hole in the movable traction seat; the traction device is characterized in that the fixed traction plate is arranged close to the front end of the traction tube, and the movable traction plate is located behind the fixed traction plate. The distraction direction of the retractor is not limited by the space of the oral vestibule, so that the traction difficulty caused by the conflict of the traction directions is effectively avoided, and the predictability and the accuracy of the distraction osteogenesis process are improved.

Description

Technical Field

[0001] The utility model belongs to the field of medical devices, in particular to a jaw distractor. The product is suitable for distraction cases in which adults and children need to move the maxilla or midface forward after osteotomy. Background Art

[0002] Mandibular distraction osteogenesis is a common clinical procedure for correcting midfacial skeletal deficiencies and bone defects. Following a full or partial maxillary osteotomy, the distractor is used to move bone fragments at a specific rate. The distractor is worn for at least six months and then removed after sufficient bone formation has occurred. However, existing mandibular distractor designs have numerous drawbacks.

[0003] One such device is an extraoral distractor, such as the "Skull Fixator" in U.S. Patent Publication No. US3391693A and the "Adjustable Midface Bone Distractor and Design Method" in Chinese Invention Patent No. ZL201010113708.X (Announcement No. CN101822568B). External distractors utilize the skull for support and are secured with transcutaneous screws. These devices are extremely uncomfortable, severely impacting patients' daily social lives, leaving scars, and potentially causing serious complications such as craniocerebral trauma.

[0004] The second type is an intraoral distractor (semi-implantable distractor), which is fixed to the maxillary bone or teeth via bone screws or brackets. Most of its components are located in the front of the mouth, making it uncomfortable and interfering with eating, pronunciation, and oral hygiene. Intraoral devices often require customization and are difficult to obtain. Due to vestibular space limitations, the two intraoral distractors cannot achieve parallel distraction vectors, affecting distraction efficiency and accuracy.

[0005] The third type is an implantable distractor, which is secured by bone screws and has most of its components placed submucosally. This makes it more comfortable than extraoral and intraoral distractors. For example, the Chinese utility model patent "Oral Internal Maxillary Distraction Device," with patent number ZL202021799787.X (publication number CN213722328U), discloses an implantable distractor comprising a sleeve, a screw, a screw tube, a movable distraction plate, and a fixed distraction plate. The screw is rotatably disposed within the sleeve, one end of the screw extending outside the sleeve and connected to a sleeve. The screw tube is slidably sleeved on the screw and threadedly connected thereto. The sleeve is provided with a slot along the sliding direction of the screw tube, one side of the screw tube passes through the slot and is fixedly connected to the movable distraction plate. The end of the sleeve away from the sleeve is fixedly connected to the fixed distraction plate. The fixed distraction plate is runway-shaped and has multiple first screw holes spaced apart. The movable distraction plate is U-shaped, with multiple second screw holes spaced apart at both ends of the movable distraction plate from the opening side toward the connection side.

[0006] In the comparative patent, the fixing plate fixed to the zygomatic bone is at the rear of the distractor, and the distraction plate fixed to the maxilla is at the front of the distractor. This results in the distractor being located in front of the zygomatic bone and protruding from the oral vestibule after positioning. This presents three problems: 1. Poor comfort, which affects oral function and hygiene maintenance; 2. Due to space limitations in the oral vestibule, it is impossible for the distractors on both sides to be positioned horizontally, which affects distraction efficiency and distance; 3. In the sagittal direction, the front of the maxilla is further posterior than the front of the zygomatic bone. This comparative patent has the problem of difficulty in positioning during surgery.

[0007] In summary, the existing implantable maxillary distractor can be further improved. Utility Model Content

[0008] The technical problem to be solved by the present invention is to provide a mandibular distractor with reasonable structure, taking into account accuracy, comfort, functionality and aesthetics in view of the above-mentioned existing technical status.

[0009] The technical solution adopted by the utility model to solve the above technical problems is: a mandibular traction device, comprising a traction tube, which is provided with a guide groove arranged along the length direction, and has a front end and a rear end; a fixed traction plate, which is fixedly arranged relative to the traction tube, and the fixed traction plate is provided with a plurality of first mounting holes for self-tapping screws to pass through; a movable traction seat, which is constrained in the guide groove and can slide axially, and the movable traction seat is provided with an axially penetrating threaded through hole; the movable traction plate is fixed on the movable traction seat, and the movable traction plate is provided with a plurality of second mounting holes for self-tapping screws to pass through; the traction screw is arranged in the guide groove and can rotate around its own axis, and the front end of the traction screw passes through the traction tube to form a driving end for connecting with a universal joint, the universal joint is used to be connected to the force rod, and the traction screw passes through and is threadedly connected to the threaded through hole on the movable traction seat; it is characterized in that: the fixed traction plate is arranged near the front end of the traction tube, and the movable traction plate is located behind the fixed traction plate.

[0010] Preferably, the fixed traction plate is located above the traction tube, and the movable traction plate is located below the traction tube. This facilitates fixing the fixed traction plate to the zygomatic bone and the movable traction plate to the upper alveolar bone, which further improves the traction device's fixed position.

[0011] As an improvement, the fixed traction plate comprises a vertical arm and a transverse arm. The vertical arm is fixed to the traction tube. The middle portion of the transverse arm connects with the top end of the vertical arm to form a T-shape. The transverse arms extend to the left and right sides with the vertical arm as the center. The first mounting holes are provided on the transverse arms. When the fixed traction plate with the above structure is fixed to the zygomatic bone, both the left and right sides of the traction tube are fixed, providing a more stable fixation.

[0012] Because the movable traction plate is located at the rear end, in order to increase the area of fixation with the alveolar bone, it is preferably provided with a vertical portion and a transverse portion. The vertical portion is fixed to the movable traction seat, and the tail end of the transverse portion is connected to the top end of the vertical portion to form an overall L-shape. The length of the transverse portion is arranged along the length of the traction tube, and the second mounting hole is provided on the transverse portion. The transverse portion is longer, which facilitates bending by the doctor and is more suitable for fixation to the upper alveolar bone.

[0013] Further improvement, the rear end of the above-mentioned guide groove is fixed with a rear plug, and the rear plug is provided with a accommodating cavity with an opening facing the guide groove; the front end of the guide groove is fixed with a front plug; the rear end of the traction screw is movably inserted into the accommodating cavity, and the front part of the traction screw has an annular shoulder that matches the front plug, and the front end of the traction screw passes through the front plug to form the driving end, and the fixed traction plate is pressed between the front end face of the traction tube and the annular shoulder of the front plug.

[0014] Preferably, the guide groove comprises a circular groove portion at the bottom and a strip groove portion at the top, the strip groove portion communicating with the circular groove portion, and the maximum radial width of the circular groove portion being greater than the width of the strip groove portion; the lower portion of the movable traction seat comprises a cylindrical portion whose shape matches the circular groove portion, the threaded through hole being provided on the cylindrical portion, the middle portion of the movable traction seat comprises a guide portion whose shape matches the strip groove portion, and the lower end face of the movable traction seat rests on the upper end face of the traction tube. Because the maximum radial width of the circular groove portion is greater than the width of the strip groove portion, the cylindrical portion at the lower portion of the movable traction seat can be constrained within the circular groove portion and can only slide forward and backward, thereby enabling more precise adjustment of the traction distance.

[0015] To facilitate accurate attachment of the movable traction plate to the movable traction seat, the movable traction seat has an upwardly protruding fixing post in the middle of its upper end surface, and the movable traction plate has a fixing hole for the fixing post to engage with. The movable traction seat has upwardly protruding inserts on both the front and rear sides of its upper end surface, and the movable traction plate has slots for the inserts to engage with the inserts. Through the positioning of the fixing post and fixing hole, and the positioning of the inserts and slots, the movable traction seat and the movable traction plate are accurately connected, and then the two are fixed by welding.

[0016] A further improvement is that the universal joint has a fixed component and a movable component. The fixed component is sleeved and fixed to the driving end, and the movable component is rotatably mounted on the fixed component and can swing up and down and left and right. The force rod is detachably connected to the movable component. This allows the force rod and the traction screw to be detached from each other. After the final traction is completed, the detachment of the force rod leaves essentially no additional components outside the patient's body, maximizing the patient's comfort and aesthetics during distraction therapy and preventing discomfort caused by the force rod during daily activities. This maximizes the patient's comfort and aesthetics during distraction therapy and prevents the traction screw from deflecting in the direction of relaxation due to inadvertent external force hitting the force rod, causing a change in the traction position. This ensures that the fixed traction plate and the movable traction plate always remain in the appropriate position, ensuring that the new bone generated is flat and the surgical quality is excellent.

[0017] To facilitate assembly and disassembly of the force rod, the force rod is constrained to the movable part by a limiting tube. The front end of the force rod has a front driving portion with a polygonal cross section, and the rear end of the force rod has a rear driving portion with a polygonal cross section. The movable part is provided with an insertion hole that matches the rear driving portion. The limiting tube is movably mounted on the force rod. The rear end of the limiting tube is detachably connected to the movable part. The force rod can rotate around its own axis relative to the limiting tube. The inner wall of the limiting tube is provided with an inner shoulder. The force rod is provided with an outer shoulder that matches the inner shoulder. When disassembling, the limiting tube only needs to be unscrewed from the movable part of the universal joint, and the force rod can be pulled away from the movable part of the universal joint to complete the disassembly. When adjustment is required, the rear driving portion of the force rod only needs to be inserted into the insertion hole of the movable part, and then the limiting tube is mounted on the force rod and threadedly connected to the movable part.

[0018] As an advantage, the outer periphery of the movable part is provided with an external thread, and the rear end of the position limiting tube is threadedly connected to the external thread. Of course, the position limiting tube and the movable part can also be connected by a screw-on method.

[0019] Compared with the prior art, the advantages of the present invention are:

[0020] 1. Place the fixed traction plate at the front end of the distractor and the movable traction plate at the rear end. Once in place, the threaded traction rod is completely hidden behind the front of the jaw and does not protrude from the oral cavity, effectively avoiding the aforementioned problems in the comparative patent. In this design, the traction tube is embedded in the lateral edge of the full alveolar ridge, above the maxillary osteotomy line, and the front end of the traction tube does not exceed the front of the jaw. This placement effectively avoids interference with normal physiological functions such as opening and closing the mouth and nasal ventilation, does not interfere with osteogenesis in the osteotomy area, and the distraction direction is not restricted by the oral vestibule space. This effectively avoids traction difficulties caused by traction direction conflicts, improves the predictability and accuracy of the distraction osteogenesis process, and is easy to remove.

[0021] 2. The retractor avoids the nasal cavity, maxillary sinus, osteotomy line, and mandibular coracoid process, and does not interfere with the osteogenesis process during the distraction stabilization period, the alveolar surgery that may be performed at the same time, and normal physiological functions such as ventilation, chewing, and speech.

[0022] 3. The traction devices on both sides of the mandible can be placed horizontally, with high traction efficiency and accurate traction distance, which is convenient for intraoperative positioning and fixation.

[0023] 4. During the distraction maintenance phase after the completion of the force traction, no distraction components are exposed inside or outside the mouth, ensuring the patient's comfort and aesthetics during the distraction treatment to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The three-dimensional structure of the embodiment of the utility model is shown as follows Figure 1 ;

[0025] Figure 2 The three-dimensional structure of the embodiment of the utility model is shown as follows Figure 2 ;

[0026] Figure 3 A cross-sectional view of an embodiment of the present utility model;

[0027] Figure 4 This is a three-dimensional exploded schematic diagram of a state where the booster rod of an embodiment of the utility model is disassembled;

[0028] Figure 5 This is a three-dimensional exploded view of an embodiment of the present utility model;

[0029] Figure 6 This is a front view schematic diagram of an embodiment of the present utility model in clinical use;

[0030] Figure 7 It is a side view of an embodiment of the present invention in clinical use. DETAILED DESCRIPTION

[0031] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0032] like Figures 1 to 5 Shown is a preferred embodiment of the present utility model.

[0033] A jaw distraction device comprising

[0034] The traction tube 1 has a guide groove 11 extending along its length and having a front end 1a and a rear end 1b. The guide groove 11 consists of a circular groove portion 111 at the bottom and a strip groove portion 112 at the top. The strip groove portion 112 communicates with the circular groove portion 111, and the maximum radial width of the circular groove portion 111 is greater than the width of the strip groove portion 112. A rear plug 2a is fixed to the rear end of the guide groove 11. The rear plug 2a has a receiving cavity 2a1 formed therein, the cavity opening toward the guide groove 11. A front plug 2b is fixed to the front end of the guide groove 11.

[0035] The fixed traction plate 3 is fixedly arranged relative to the traction tube 1, and is provided with a plurality of first mounting holes 31 for self-tapping screws to pass through. The fixed traction plate 3 has a vertical arm 3a and a horizontal arm 3b. The vertical arm 3a is fixed to the traction tube 1, and the middle part of the horizontal arm 3b is connected to the top end of the vertical arm 3a to form a T-shape as a whole. The horizontal arm 3b extends to the left and right sides with the vertical arm 3a as the center, and the first mounting hole 31 is provided on the horizontal arm 3b.

[0036] The movable traction seat 5 is constrained within the guide groove 11 and is capable of axial sliding movement. A threaded through-hole 511 is formed axially through the movable traction seat 5. An upwardly projecting fixing post 53 is provided in the middle of the upper end surface of the movable traction seat 5. A fixing hole 62 is provided on the movable traction plate 6 for receiving the fixing post 53. Upwardly projecting insertion blocks 54 are provided on the front and rear sides of the upper end surface of the movable traction seat 5. Slots 63 are provided on the front and rear sides of the movable traction plate 6 for receiving the insertion blocks 54. The lower portion of the movable traction seat 5 has a cylindrical portion 51 whose shape matches the circular groove 111. The threaded through-hole 511 is provided in this cylindrical portion 51. A guide portion 52 is provided in the middle of the movable traction seat 5, whose shape matches the strip-shaped groove 112. The lower end surface of the movable traction seat 5 rests on the upper end surface of the traction tube 1.

[0037] The movable traction plate 6 is fixed on the movable traction seat 5, and is provided with a plurality of second mounting holes 61 for self-tapping screws to pass through. The movable traction plate 6 has a vertical portion 6a and a transverse portion 6b. The vertical portion 6a is fixed on the movable traction seat 5, and the tail end of the transverse portion 6b is connected to the top end of the vertical portion 6a to form an L-shape as a whole. The length direction of the transverse portion 6b is arranged along the length direction of the traction tube 1, and the second mounting holes 61 are provided on the transverse portion 6b.

[0038] The traction screw 7 is arranged in the guide groove 11 and can rotate around its own axis. The front end of the traction screw 7 passes through the traction tube 1 to form a driving end 72 for connecting to the universal joint 8. The universal joint 8 is used to connect to the force rod 9. The traction screw 7 passes through and is threadedly connected to the threaded through hole 511 on the movable traction seat 5; the rear end of the traction screw 7 is movably inserted into the accommodating cavity 2a1, and the front part of the traction screw 7 has an annular shoulder 71 that is matched with the front plug 2b. The front end of the traction screw 7 passes through the front plug 2b to form the driving end 72.

[0039] The fixed traction plate 3 is positioned near the front end 1a of the traction tube 1, and the movable traction plate 6 is located behind the fixed traction plate 3. Specifically, the fixed traction plate 3 is pressed and welded between the front end surface of the traction tube 1 and the annular shoulder 2b1 of the front plug 2b. The fixed traction plate 3 is located above the traction tube 1, and the movable traction plate 6 is located below the traction tube 1.

[0040] The universal joint 8 of this embodiment has a fixed part 81 and a movable part 82. The fixed part 81 is sleeved and fixed on the driving end 72. The movable part 82 is rotatably mounted on the fixed part 81 and can swing up and down and left and right. The force rod 9 is detachably connected to the movable part 82.

[0041] The force rod 9 is constrained to the movable component 82 by a limiting tube 10. The front end of the force rod 9 has a front driving portion 9a with a polygonal cross-section, and the rear end of the force rod 9 has a rear driving portion 9b with a polygonal cross-section. The movable component 82 is provided with an insertion hole 821 that matches the rear driving portion 9b. The limiting tube 10 is movably mounted on the force rod 9. The rear end of the limiting tube 10 is detachably connected to the movable component 82. The force rod 9 can rotate about its own axis relative to the limiting tube 10. The inner wall of the limiting tube 10 is provided with an inner shoulder 101, and the force rod 9 is provided with an outer shoulder 9c that matches the inner shoulder 101. The outer periphery of the movable component 82 is provided with an external thread 822, and the rear end of the limiting tube 10 is threadedly connected to the external thread 822.

[0042] In this embodiment, the movable traction plate 3 and the fixed traction plate 6 are made of pure titanium TA3, and other components are made of titanium alloy TC4. The hardness of titanium alloy is ≥260HV10, and the hardness of pure titanium is ≥150HV10.

[0043] When using, Figure 6 、 7As shown, select the appropriate model of the mandibular traction device and determine the installation position of the traction device, make a small incision in the corresponding mandibular soft tissue, fix the fixed traction plate 3 on the mandible on one side of the incision, and then fix the movable traction plate 6 on the alveolar bone below the incision. When adjusting, rotate the force rod 9 in a clockwise direction (in the direction indicated by the arrow on the handle) to drive the traction screw 7 to rotate. According to the threaded connection adjustment working principle of the traction screw 7 and the threaded through hole 511, the movable traction plate 6 and the movable traction seat 5 are forced to slide forward or backward relative to the screw 4. The traction distance is 0.4 mm for each rotation of the screw 4, creating a gap. The traction force is used to induce the mandible's own osteogenesis ability and continuously form new bone to fill this gap. The threaded transmission of the screw 4 and the threaded hole 511 can accurately and slowly adjust the traction distance. After achieving the expected clinical effect, the traction is stopped.

[0044] Disassemble the adjustment handle 9: Figure 4 As shown, the limiting tube 10 is unscrewed from the movable part 82 of the universal joint 8, and the force rod 9 can be pulled out of the movable part 82 of the universal joint 8 to complete the disassembly;

[0045] Install the adjustment handle 9: Figures 1 to 3 As shown, when adjustment is required, it is only necessary to insert the rear driving portion 9b of the force rod 9 into the insertion hole 821 on the movable part 82, and then put the limit tube 10 on the force rod 9 and complete the threaded connection with the movable part 82. The rotation of the force rod 9 drives the traction screw 7 to rotate along with the universal joint 8.

[0046] It should be noted that in the description of this embodiment, the terms "front, back", "left, right", "inside, outside", "upper, lower" and the like indicating directions or positional relationships are all based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention. The terms "install", "connect", and "connected" should be understood in a broad sense. For example, they can be fixed connections, detachable connections, or integral connections; they can be directly connected, or indirectly connected through an intermediate medium, or they can be internal connections between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A jaw distractor comprising A traction tube (1) is provided with a guide groove (11) arranged along the length direction and has a front end (1a) and a rear end (1b); A fixed traction plate (3) is fixedly arranged relative to the traction tube (1), and a plurality of first mounting holes (31) for self-tapping screws to pass through are formed on the fixed traction plate (3); A movable traction seat (5) is constrained in the guide groove (11) and can slide axially, and an axially penetrating threaded through hole (511) is formed on the movable traction seat (5); A movable traction plate (6) is fixed on the movable traction seat (5), and a plurality of second mounting holes (61) for self-tapping screws to pass through are formed on the movable traction plate (6); A traction screw (7) is arranged in the guide groove (11) and can rotate around its own axis. The front end of the traction screw (7) passes through the traction tube (1) to form a driving end (72) for connecting with a universal joint (8). The universal joint (8) is used to connect with the force rod (9). The traction screw (7) passes through and is threadedly connected to the threaded through hole (511) on the movable traction seat (5). Its characteristics are: The fixed traction plate (3) is arranged close to the front end (1a) of the traction tube (1), and the movable traction plate (6) is located behind the fixed traction plate (3).

2. The jaw distractor according to claim 1, characterized in that: The fixed traction plate (3) is located above the traction tube (1), and the movable traction plate (6) is located below the traction tube (1).

3. The jaw distractor according to claim 2, characterized in that: The fixed traction plate (3) has a vertical arm (3a) and a horizontal arm (3b); the vertical arm (3a) is fixed to the traction tube (1); the middle portion of the horizontal arm (3b) is connected to the top end of the vertical arm (3a) to form a T-shape as a whole; the horizontal arm (3b) extends to the left and right sides with the vertical arm (3a) as the center; and the first mounting hole (31) is provided on the horizontal arm (3b).

4. The jaw distractor according to claim 3, characterized in that: The movable traction plate (6) comprises a vertical portion (6a) and a transverse portion (6b); the vertical portion (6a) is fixed on the movable traction seat (5); the tail end of the transverse portion (6b) is connected to the top end of the vertical portion (6a) to form an L-shape as a whole; the length direction of the transverse portion (6b) is arranged along the length direction of the traction tube (1); and the second mounting hole (61) is provided on the transverse portion (6b).

5. The jaw distractor according to claim 1, characterized in that: The rear end of the guide groove (11) is fixed with a rear plug (2a), and a receiving cavity (2a1) with an opening toward the guide groove (11) is provided in the rear plug (2a); the front end of the guide groove (11) is fixed with a front plug (2b); the rear end of the traction screw (7) is movably inserted into the receiving cavity (2a1), and the front part of the traction screw (7) has an annular shoulder (71) that is matched with the front plug (2b); the front end of the traction screw (7) passes through the front plug (2b) to form the driving end (72), and the fixed traction plate (3) is pressed between the front end surface of the traction tube (1) and the annular shoulder (2b1) of the front plug (2b).

6. The jaw distractor according to claim 5, characterized in that: The guide groove (11) is composed of a circular groove portion (111) located at the bottom and a strip groove portion (112) located at the top. The strip groove portion (112) is connected to the circular groove portion (111), and the maximum radial width of the circular groove portion (111) is greater than the width of the strip groove portion (112). The lower part of the movable traction seat (5) has a cylindrical portion (51) whose shape matches the circular groove portion (111). The threaded through hole (511) is provided on the cylindrical portion (51). The middle part of the movable traction seat (5) has a guide portion (52) whose shape matches the strip groove portion (112). The lower end surface of the movable traction seat (5) is placed on the upper end surface of the traction tube (1).

7. The jaw distractor according to claim 6, characterized in that: The middle part of the upper end surface of the movable traction seat (5) is provided with an upwardly protruding fixing column (53), and the movable traction plate (6) is provided with a fixing hole (62) for the fixing column (53) to be plugged in; the front and rear sides of the upper end surface of the movable traction seat (5) are provided with upwardly protruding plug blocks (54), and the front and rear sides of the movable traction plate (6) are provided with slots (63) for the plug blocks (54) to be plugged in.

8. The jaw distractor according to claim 1, characterized in that: The universal joint (8) comprises a fixed part (81) and a movable part (82), wherein the fixed part (81) is sleeved and fixed on the driving end (72), and the movable part (82) is rotatably mounted on the fixed part (81) and can swing up and down and left and right, and the force rod (9) is detachably connected to the movable part (82).

9. The jaw distractor according to claim 8, characterized in that: The force rod (9) is constrained on the movable part (82) through a limiting tube (10); the front end of the force rod (9) has a front driving part (9a) with a polygonal cross section, and the rear end of the force rod (9) has a rear driving part (9b) with a polygonal cross section; the movable part (82) is provided with an insertion hole (821) matching the rear driving part (9b); the limiting tube (10) is movably sleeved on the force rod (9); the rear end of the limiting tube (10) is detachably connected to the movable part (82); the force rod (9) can rotate around its own axis relative to the limiting tube (10); an inner shoulder blade (101) is provided on the inner wall of the limiting tube (10); and an outer shoulder (9c) matching the inner shoulder blade (101) is provided on the force rod (9).

10. The jaw distractor according to claim 9, characterized in that: The outer periphery of the movable component (82) is provided with an external thread (822), and the rear end of the limiting tube (10) is threadedly connected to the external thread (822).

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