CN111419372A - A mandibular reduction device - Google Patents

Abstract

The invention relates to a mandible reduction device, comprising a fracture connection part matched with the curvature of the lower edge of the mandible; The traction part on both sides of the connecting part is provided with a positioning hole, a mounting hole is set on the bone-connecting part, a traction hole is set at one end of the traction part away from the connecting part, and the bone-connecting part is set in the middle of the connecting part, The connecting portion, the traction portion and the bone-connecting portion are all connected to the mandible through traction nails; the mandible reduction device provided by the present invention reduces and effectively fixes the fracture, restores the anatomical structure of the mandible to the greatest extent, and promotes fracture healing, Improve the clinical symptoms of patients and improve the clinical treatment effect.

Description

A mandibular reduction device

technical field

The invention belongs to the technical field of medical devices, and in particular relates to a mandibular repositioning device.

Background technique

Jaw fracture is a common disease in oral and maxillofacial surgery, and it is also one of the main fracture forms. Clinically, surgical treatment is mainly used to reduce the fracture and restore the anatomical structure, so as to restore the oral chewing function and bite relationship to normal. Restore the appearance of the face to protect the physical and mental health of patients and improve their quality of life. Because the jaw has a special anatomical structure and is involved in various functions of oral chewing, swallowing, pronunciation and respiration, its physiological requirements are relatively high, and the blood supply there is rich, and the fracture ends heal faster. If there is no good reduction and fixation in the internal organs, it will easily lead to dislocation healing, which will seriously affect the clinical efficacy and prognosis.

In the past, the traditional surgical treatment for jaw fractures in clinical practice was dental arch splint intermaxillary traction ligation, which could be treated with stainless steel wire bone fixation. Although it can meet the requirements of reduction treatment, it has the following disadvantages in the clinical application process: the placement of the dental arch splint and the ligation of the wire are complicated, which will inevitably damage the periodontal tissue; the hook end and a large number of wires carried by the dental arch splint are exposed to the oral cavity. Internally, the patient has obvious foreign body sensation, poor comfort, and is not conducive to oral hygiene; this operation takes a long time and is difficult, especially for patients with deep coverage, crowded dentition and limited mouth opening , it is difficult to clinically cause, and some patients are even difficult to perform to meet the clinical requirements; the stability is poor, the fracture site will be in a state of fretting for a long time and stimulate cartilage osteogenesis, which will adversely affect the healing of fractures and the recovery of the bite relationship; Can not provide enough support, it is easy to shift or twist due to the influence of surrounding muscles or mandibular movement, which affects the growth of capillary blood vessels and the differentiation of osteocytes at the broken end, delays healing, and requires TMJ immobilization during the overall treatment. The patient's eating, language and oral hygiene all have an impact, which not only interferes with the patient's life and work, but also seriously affects the patient's nutritional intake, resulting in osteoporosis and reduced healing ability. Long-term restriction of joint movement will also cause muscle damage. Atrophy and even form degenerative joint disease.

The mandible is the only large active bone in the maxillofacial region and participates in the formation of the temporomandibular joint. Therefore, it has a great impact on the masticatory function after injury. At present, there is a lack of a fracture fixation reducer with a wide range of applications and low manufacturing cost for related treatment. .

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the problems raised in the background art, and provide a mandibular reduction device, which can reduce and effectively fix the fracture, restore the anatomical structure of the mandible to the greatest extent, promote fracture healing, and improve the clinical symptoms of patients, Improve the clinical treatment effect.

The object of the present invention is achieved in this way:

A mandible reduction device, comprising a fracture connection part matched with the curvature of the lower edge of the mandible; The traction part, the connecting part is set with a positioning hole, the bone-connecting part is set with a mounting hole, the end of the traction part away from the connecting part is provided with a traction hole, the bone-connecting part is set in the middle of the connecting part, and the connecting part is located in the middle of the connecting part. The mandible part, the distraction part and the bone connection part are all connected to the mandible through the distraction nail.

Further, the connecting part is a small titanium plate obtained by 3D printing with additive manufacturing technology according to the patient's post-operative mandibular model, and both the bone connecting part and the traction part are 3D printed with additive manufacturing technology according to the patient's model. The titanium mesh structure obtained by shaping the postoperative mandibular model.

Further, the thickness of the titanium mesh is 0.3-0.5 mm, the aperture of the titanium mesh is 2-5 mm, and the thickness of the titanium plate is 1.5-2.5 mm.

Further, the positioning holes are set to 4-8, the traction holes are set to 2-4, the installation holes, the traction holes and the positioning holes are all stepped holes, and the major diameter of the stepped holes is 3-5mm, The small diameter of the stepped hole is 1-3 mm.

Further, the traction nails are made of bi-cortical titanium nails, and the traction nails are arranged in the middle of adjacent tooth roots.

Further, the traction pins are arranged between the canines and the roots of the first molars, and the traction pins are arranged at a distance of 5-8 mm from the gingival margin.

Further, an osteotomy end is provided on the side of the bone connecting portion facing the labial and cheek groove and along the crease direction of the fracture.

Further, a collagen layer and a hydroxyapatite layer are sequentially coated on the outer surfaces of the connecting portion, the traction portion, and the bone-connecting portion, and the collagen layer is a double-layer absorbable collagen film prepared by processing and purifying porcine collagen.

Further, the connection part, the distraction part and the bone-connecting part are treated with hydroxyapatite spraying, pickling and acid etching technology to treat the specific titanium alloy area after laser sintering.

Further, the manufacturing method of the mandibular reduction device includes the following steps:

1) Before mandibular osteotomy, use digital technology, according to the surgical plan, and combine with 3D printing technology to make the patient's mandible model after surgery. Before the operation, the mandibular anterior and posterior views and the three-dimensional reconstruction of the dental and maxillofacial cone beam CT were determined. Root position, choose the implantation position of the traction nail, between the root and the root tip, and avoid the mandibular neural canal, maxillary sinus and other anatomical structures, determine the fracture situation and location of the patient, and use the postoperative mandibular model to analyze the fractures. The standard medical titanium metal strip of the screw hole is shaped to obtain a connection part, a traction part and a reconstruction part that match the curved shape of the patient's mandibular model after operation;

2) Give the patient general anesthesia through nasal tracheal intubation, remove the bone fragments at the fracture end first, adjust the bone segments according to the anatomical relationship, carefully separate the maxillofacial nerve branches, fully expose the fracture position, and reset according to the anatomical relationship and the occlusal relationship For fractures, an intraoral gingival, mucoperiosteal angle flap incision was designed obliquely from the midpoint of the anterior edge of the ascending ramus to the first molar, and the periosteum was separated. If there is a large degree of loosening or there are impacted teeth, extraction is performed during the operation;

3) According to the specific conditions of the fracture site, fully release the fracture segment, reduce the two broken ends of the fracture, implant the reduction device along the external oblique line for cortical bone fixation, adjust the curvature of the titanium plate, and fix the broken end of the fracture to make it close to each other. Bone surface, drilled with screws and fixed;

4) On the 1st day after surgery, elastic traction with rubber bands can be started, and then the number of rubber bands can be gradually reduced and fixed for 2 to 3 weeks. After the traction is removed, mouth-opening function training can be performed in the early stage. After 1 month of follow-up, the intermaxillary can be removed if the occlusion recovers well. Traction nails, titanium plates are removed in 6 to 12 months.

Further, the tensile strength F1 of the titanium plate of the connecting portion is 80-100MPa, the stress F2 of the titanium plate satisfies 45-120Mpa, and F1·F2 is greater than or equal to 3860Mpa and less than or equal to 11280MPa.

Further, the elastic modulus E of the titanium mesh of the bone joint is 95063-11841Mpa, the Poisson's ratio υ of the titanium mesh is 0.25-0.56, the yield strength F of the titanium mesh is 780-950Mpa, and the elastic modulus Quantity E, yield strength F and Poisson's ratio υ satisfy (E+F)/υ not less than 20855 and not more than 48964.

Further, the maximum load S of the titanium mesh is 41.38-43.71N, and the bending strength σ of the titanium mesh is 486.22-520.58Mpa.

Further, the strain value of the connecting portion satisfies:

F= [(F1·F1)+(e-115)]/ υ·ρ ^1.36 ,

Among them, ρ is density, e is Young's modulus, and 40≤e≤19561MPa.

Further, the flexural strength σ of the bone joint satisfies:

σ=3FL/2bh ² ,

Among them, L represents the span (mm) of the bone part, b represents the width (mm) of the bone part, and h represents the height (mm) of the bone part.

Compared with the prior art, the beneficial effects of the present invention are:

1. The present invention provides a mandibular reduction device. The 3D printed titanium alloy mandibular bone plate is a repair material with good biocompatibility and good repair performance. Through the 3D printing technology of titanium alloy, it can not only quickly produce Various personalized mandibular bone plates can also achieve stable and firm internal fixation, induce bone tissue reconstruction in bone defect areas, and have good bone quality. The periodontal condition is good, the complication rate is low, and the curative effect is remarkable.

2. The mandible reduction device provided by the present invention provides sufficient retention space by using the connecting part with positioning holes, and fits with the mandible without tension, which can achieve the effect of anatomical reduction and retention. The traction part is used for fixation, and the position can be adjusted according to the actual situation, avoiding the mandibular nerve canal, and can fix the fracture site in the three-dimensional direction to overcome the shear, bending and torsion forces in the bone, and its large space design It provides conditions for better blood supply to the fracture site, and the bone connection part is connected to the fracture crease, that is, the width of the titanium mesh should be exactly the same as the extent of the bone defect, so as to guide the reduction.

3. The mandible reduction device provided by the present invention, through 3D printing technology, makes the edge of the titanium mesh bone bracket round and stewed, and the size and scope are matched with the bone defect area, and no surgical procedures such as trimming and bending are required, which can be greatly shortened. Operation time, simple and convenient operation, through computer-aided design and computer-aided manufacturing of personalized bone scaffolds, design and manufacture of personalized bone scaffolds that match the bone defect area, so as to avoid complicated surgical procedures such as bending and trimming during the operation, so as to reduce the need for surgery time and reduce the incidence of postoperative complications.

4. The mandible reduction device provided by the present invention adopts a type A plate structure, which generates a small strain area in the bone around the fracture line, achieves the effect of strong fixation, fully reflects the principle of biomechanics, and ensures that the mandibular fracture can be effectively fixed. To achieve the correct reduction of the fracture.

Description of drawings

FIG. 1 is a schematic structural diagram of a mandibular reduction device according to the present invention.

Fig. 2 is a schematic diagram of the bone joint part of a mandibular reduction device of the present invention.

Fig. 3 is a schematic diagram of a mandibular repositioning device of the present invention in use state.

In the figure: 1. Connection part; 2. Bone connection part; 3. Traction part; 4. Mandible; 5. Traction nail; 11. Positioning hole; 21. Installation hole;

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, the field of All other embodiments obtained by a person of ordinary skill without creative work fall within the protection scope of the present invention.

Example 1

1 and 2, a mandible reduction device, comprising a fracture connection portion 1 that matches the curvature of the lower edge of the mandible 4, and a bone connection portion 2 that is arranged on the upper end of the fracture connection portion 1 and is adapted to the curvature of the labial and cheek grooves. and the traction part 3 arranged on the connecting part 1 and on both sides of the bone-connecting part 2, the connecting part 1 is a small titanium plate obtained by printing the model of the patient's post-operative mandible 4 through the additive manufacturing technology 3. Both the bone joint part 2 and the traction part 3 are titanium mesh structures obtained by 3D printing with additive manufacturing technology and shaped according to the patient's postoperative mandible 4 model.

A positioning hole 11 is set on the connecting part 1 , a mounting hole 21 is set on the bone connecting part 2 , a pulling hole 31 is set on the end of the traction part 3 away from the connecting part 1 , and the bone connecting part 2 is set at the end of the connecting part 1 . In the middle, an osteotomy end 22 is provided on the side of the bone connecting portion 2 facing the labial and buccal groove along the crease direction of the fracture.

The connecting portion 1, the traction portion 3 and the bone-connecting portion 2 are sequentially connected to the mandible 4 through the positioning hole 11, the traction hole 31 and the installation hole 21 through the traction nail 5. The traction nail 5 is made of bicortical titanium nails. Described traction nail 5 is set in the middle of adjacent tooth root, described traction nail 5 is set between canine and first molar root, when described traction nail is implanted, the nail is perpendicular to the bone surface or slightly inclined to the direction of the root, and the position is not required. It is too close to the vestibular sulcus to prevent the postoperative mucosa from covering the traction pins and aggravating the pain of the patient.

Titanium plate strong internal fixation for the treatment of mandibular fractures Using titanium alloy bone plates and screws to fix the fracture ends, which can make the titanium plate close to the bone surface and help the broken ends resist the displacement tension. It has the characteristics of good stability, firmness and durability. Titanium alloy It has the characteristics of high strength, light weight and low density, and its elastic modulus is close to that of natural bone, which can better simulate the physiological function of normal bone tissue. In addition, the corrosion resistance and biocompatibility of titanium plates are much better than those of traditional steel plates, which can greatly reduce the incidence of rejection after implantation. Mandibular rehabilitation training can be performed one week after surgery, which is much earlier than traditional intermaxillary surgery. Ligation traction fixation method.

Example 2

In conjunction with Fig. 3, a mandible reduction device, comprising a fracture connection portion 1 that matches the curvature of the lower edge of the mandible 4, a bone connection portion 2 that is positioned on the upper end of the fracture connection portion 1 and is adapted to the radian of the lip-cheek groove and is located in the The traction parts 3 on the connecting part 1 and on both sides of the bone-connecting part 2. The connecting part 1 is a small titanium plate obtained by printing a model of the patient's post-operative mandible 4 through the additive manufacturing technology. 2 and the traction part 3 are titanium mesh structures obtained by 3D printing with additive manufacturing technology according to the patient's postoperative mandible 4 model, the thickness of the titanium mesh is 0.5mm, and the aperture of the titanium mesh is 3mm , the thickness of the titanium plate is 2mm.

The connecting portion 1, the traction portion 3 and the bone-connecting portion 2 are sequentially connected to the mandible 4 through the positioning hole 11, the traction hole 31 and the mounting hole 21 through the traction nail 5, which is set at a distance of 5-8 mm from the gingival margin. , the size of the traction nail 5 is 1.7mm×5mm.

By using the connecting part 1 with the positioning hole 11, a sufficient retention space is provided, which can fit with the mandible 4 without tension, and can achieve the effect of anatomical reduction and retention. Adjust the position according to the actual situation, avoid the mandibular nerve canal, and fix the fracture site in three-dimensional direction to overcome the shear, bending and torsion forces in the bone, and its larger space is designed to provide better blood supply to the fracture site. In order to meet the conditions, the bone joint part 2 is connected with the crease of the fracture, that is, the width of the titanium mesh should be completely consistent with the extent of the bone defect, so as to guide the reduction.

The small titanium plate is small in size, strong and easy to shape. It has outstanding compressive and bending resistance and biocompatibility. It can be tightly fitted on the bone surface and can ensure a good combination with the bone surface. Taking it out, it can be retained in the body for a long time. It is better to use a small titanium plate for solid internal fixation. Displacement, improve the three-dimensional stability effect, and provide a good healing environment for the fractured end. The solid internal fixation technology can provide three-dimensional stability and interosseous pressure at the fracture end, allowing early physiological activities to avoid the interference caused by the need to brake the temporomandibular joint for intermaxillary traction, which is more in line with its biomechanical requirements and will not Affect the patient's nutritional intake and promote healing.

The use of intermaxillary traction nails for intermaxillary traction can make up for the insufficiency of small titanium plates for solid internal fixation. This intermaxillary traction is simple and safe, avoiding the use of a large number of wires, which would cause damage to the surrounding tissue and mucosa and prevent the wires from passing through. The damage to the periodontal tissue in the interdental space can reduce the cross-infection of intraoral infectious diseases, and the titanium nails are less exposed in the oral cavity after implantation, the patient feels less foreign body, and the comfort is high, which is convenient for oral cleaning and helps Maintain good oral hygiene, the use of titanium intermaxillary traction nails can be well combined with the tissue and can withstand the large traction force between the jaws for a long time, providing sufficient support and stability for fixation and traction, which can effectively reduce fixation. The loosening of the traction device provides a stable and good healing environment for the fractured end. It has low requirements and dependence on the remaining tooth tissue and periodontal, and can be adapted to various edentulous patients or patients with poor dental and periodontal conditions. At the same time, the operation process does not need to open the mouth greatly, which solves the operation problem for patients with limited mouth opening, and the scope of its clinical indications has been significantly expanded.

Example 3

The tensile strength F1 of the titanium plate of the connecting portion is 80-100MPa, the stress F2 of the titanium plate is 45-120Mpa, and F1·F2 is greater than or equal to 3860Mpa and less than or equal to 11280MPa.

The elastic modulus E of the titanium mesh of the bone joint is 95063-11841Mpa, the Poisson's ratio υ of the titanium mesh is 0.25-0.56, the yield strength F of the titanium mesh is 780-950Mpa, the elastic modulus E, Yield strength F and Poisson’s ratio υ satisfy (E+F)/υ not less than 20855 and not more than 48964, the maximum load S of the titanium mesh is 41.38-43.71N, and the bending strength σ of the titanium mesh is 486.22-520.58 Mpa.

The strain value of the connection part satisfies: F=[(F1·F1)+(e-115)]/υ·ρ ^1.36 , where ρ is the density, e is the Young's modulus, and 40≤e≤19561MPa.

The flexural strength σ of the bone part satisfies: σ=3FL/2bh ² , where L represents the span (mm) of the bone part, b represents the width (mm) of the bone part, and h represents the height (mm) of the bone part.

In the reset device provided by the invention, the strain value of the titanium plate is 6-10N, and the titanium mesh with a thickness of 0.5mm and an aperture of 3mm has the best bearing capacity.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, etc. made within the protection scope of the present invention should be included within the protection scope of the present invention.

Claims (7)

1. A mandible reduction device, characterized in that it comprises a fracture connection portion (1) that matches the curvature of the lower edge of the mandible (4), and a fracture connection portion (1) that is arranged at the upper end of the fracture connection portion (1) and is suitable for the curvature of the labial and cheek groove. The matching bone-connecting part (2) and the traction parts (3) arranged on the connecting part (1) and on both sides of the bone-connecting part (2) are provided with positioning holes (11) on the connecting part (1), and the bone-connecting part (1) is provided with a positioning hole (11). A mounting hole (21) is provided on the portion (2), a traction hole (31) is provided at the end of the traction portion (3) away from the connecting portion (1), and the bone-connecting portion (2) is provided in the middle of the connecting portion (1). , the connecting portion (1), the traction portion (3) and the bone-connecting portion (2) are all connected to the mandible (4) through a traction nail (5). 2 . The mandible reduction device according to claim 1 , wherein the connecting part ( 1 ) is obtained by shaping and printing according to the post-operative mandibular ( 4 ) model of the patient through additive manufacturing technology 3 . The small titanium plate, the bone joint part (2) and the distraction part (3) are both titanium mesh structures obtained by 3D printing with additive manufacturing technology and shaped according to the patient's postoperative mandible (4) model. 3. The mandibular reduction device according to claim 2, wherein the thickness of the titanium mesh is 0.3-0.5mm, the aperture of the titanium mesh is 2-5mm, and the thickness of the titanium plate is 1.5-2.5mm. 4 . The mandibular reduction device according to claim 1 , characterized in that 4-8 of the positioning holes ( 11 ) are arranged, 2-4 of the traction holes ( 31 ) are arranged, and the mounting holes are arranged 4 . (21), the traction hole (31) and the positioning hole (11) are all stepped holes, the large diameter of the stepped hole is 3-5 mm, and the small diameter of the stepped hole is 1-3 mm. 5 . The mandibular reduction device according to claim 1 , wherein the traction nails ( 5 ) are made of bicortical titanium nails, and the traction nails ( 5 ) are arranged in the middle of adjacent tooth roots. 6 . 6 . The mandibular reduction device according to claim 5 , wherein the traction nail ( 5 ) is arranged between the canine and the root of the first molar, and the traction nail ( 5 ) is 5 inches from the gingival margin. 7 . Set at -8mm. 7 . The mandibular reduction device according to claim 1 , wherein the osteotomy end ( 22 ) is provided on the side of the bone connecting portion ( 2 ) facing the labial and buccal groove and along the crease direction of the fracture. 8 .

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