RU2794644C1 - Device for maxillofacial surgery and surgical dentistry - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: device for maxillofacial surgery and surgical dentistry, including a plate with the possibility of its bending and torsion, intended for fixation to the surface of the bone, containing at least a base segment having at least a pair of through holes for screws in the base segment along sides, and screws designed for screwing into the bone and fixing the plates to the bone surface. The plate has different stiffness: low, medium and high. The plate of low rigidity is characterized by its being made of pure titanium and has a thickness of up to 1 mm. The plate of medium hardness is characterized by its being made of a titanium-aluminum-vanadium alloy and has a thickness of 1 to 1.5 mm inclusive. The high rigidity plate is characterized by its being made of a titanium-aluminum-vanadium alloy and has a thickness of over 1.5 mm. The plate with a thickness of 1 mm has a rectangular cross section. The plate with a thickness of more than 1 mm has a cross-section with roundings to the sides. Through holes in the base segment of the plates are made with an internal screw thread. The screw is made in such a way that each screw head is made with an external screw thread on the side surface. Each screw head has a cross slot for a screwdriver. The screw is made with the ability to deviate when screwing at an angle of 12 to 15 degrees in opposite directions from the central longitudinal axis of the through hole. The screw thread on the cylindrical part of the screw smoothly transitions into the external screw thread on the side surface of the screw head with the possibility of forming a reliable spatial structure after screwing. The base segment of the plates is characterized by the following parameters: the width of the base segment of the plates is 2.8–4.5 mm, the diameter of the through holes on the sides of the base segment of the plates is 5–7 mm, the thickness of the base segment of the plates is 0.8–2.2 mm. The base segment of the plates is made either rectilinear in plan or arcuate in plan and its length between the axes of its adjacent through holes closest to the center is 11–30 mm.

EFFECT: invention provides optimization of device design, reduction of risks of its breakage, increase of connection reliability and, as a result, improvement of operation conditions, reduction of risk of operating and postoperative complications due to increase of osteosynthesis reliability.

9 cl, 24 dwg

Description

The invention relates to maxillofacial surgery and is intended for the correction of congenital and acquired deformities of the facial skeleton.

With congenital and acquired anomalies of the upper and lower jaws (size, position, shape), the main stage of treatment is orthognathic surgery, which consists in osteotomy of the jaws with setting the dentition in an orthognathic ratio and fixing the jaws in the correct position with titanium plates.

Known devices for maxillofacial surgery containing a plate and screws made of titanium-containing alloy (Ti-6Al-7Nb ASTM F 1295 - 16) (1), (2).

A device for maxillofacial surgery is known, containing screws and a plate, including a plate with the possibility of bending and torsion, intended for fixation to the bone surface, containing at least a base segment having at least a pair of through holes for screws in the base segment on the sides, and screws intended for screwing into the bone of the lower and / or upper jaw and fixing the plate to the surface of the bone (3).

A disadvantage of the known device is the risk of unreliable connection of bone fragments by this device with the used parameters of the plates, as well as the risk of operational and postoperative complications due to insufficient reliability of the connection, for example, with excessive chewing load in the postoperative period.

The technical problem solved by the claimed device is:

- reducing the risks and frequency of intra- and postoperative complications by increasing the stability of osteosynthesis,

- expanding the boundaries of safe movement of osteotomized fragments to achieve the optimal result of the operation,

- reduction of terms of rehabilitation of patients.

The technical result achieved by implementing the developed device consists in optimizing the design of the device, reducing the risk of its breakdown, increasing the reliability of the connection and, as a result, improving the conditions for the operation, reducing the risk of operating and postoperative complications due to increased reliability of osteosynthesis.

The specified technical result is achieved by a device for maxillofacial surgery and surgical dentistry, including a plate with the possibility of bending and torsion, designed for fixation to the bone surface, containing at least a base segment having at least a pair of through holes for screws in the base segment on the sides, and screws designed for screwing into the bone and fixing the plates to the surface of the bone, in which the plate has different rigidity: low, medium and high, and the plate of low rigidity is characterized by the fact that it is made of pure titanium and has a thickness up to 1 mm, the plate of medium rigidity is characterized by the fact that it is made of a titanium-aluminum-vanadium alloy and has a thickness of 1 mm to 1.5 mm inclusive, the plate of high rigidity is characterized by the fact that it is made of a titanium-aluminum-vanadium alloy and has a thickness more than 1.5 mm, moreover, the plate with a thickness of 1 mm has a rectangular cross section, and the plate with a thickness of more than 1 mm has a cross section with roundings to the sides, while the through holes in the base segment of the plates are made with an internal screw thread, while the screw made so that each screw head is made with an external screw thread on the side surface, on the head of each screw there is a cross slot for a screwdriver, and the screw is made with the ability to deviate when screwing at an angle of 12 to 15 degrees in opposite directions from the central longitudinal axis of the through hole, and the screw thread on the cylindrical part of the screw smoothly passes into the external screw thread on the side surface of the screw head with the possibility of forming a reliable spatial structure after screwing in, and the base segment of the plates is characterized by the following parameters: the width of the base segment of the plates is 2.8-4.5 mm, the diameter of the through holes on the sides of the base segment of the plates 5-7 mm, the thickness of the base segment of the plates is 0.8-2.2 mm, while the base segment of the plates is made either straight in plan or arcuate in plan and its length between the axes of its adjacent through holes 11-30 mm.

At the same time, in the device, a plate of low rigidity is intended for installation on the upper jaw, and a plate of low, medium and high rigidity is intended for installation on the lower jaw.

At the same time, in the device, the degree of plate rigidity - small, medium and high - is characterized by color marking.

At the same time, the device has a cross slot for a screwdriver on the screw head, the slots of the cross slot are made with a concave surface in the shape of a circle and have recesses at the intersection.

At the same time, there are risks in the device on the surface of the base segment of the plate.

In this case, the distance between the risks in the device is 1 mm.

At the same time, in the device, the plate, in addition to the base segment, has at least one additional plate segment designed for optimal stress redistribution in the base segment of the plates with the possibility of bending and torsion and with a through hole on the end part for screwing in the screw, which in plan departs from the part of the base segment of the plates with a through hole, and the through hole in the additional segment of the plates, designed for optimal redistribution of stresses in the nodes of the base segment of the plates, has an internal screw thread.

At the same time, in the device, the plate, in addition to the base segment, has at least one elongated additional plate segment for fixing the bone with the possibility of bending and torsion and with a through hole on the end part for screwing in the screw, which in plan extends from the part of the base plate segment with a through hole, and its length from the center of its through hole to the center of the nearest through hole on the base segment of the plates is 12-14 mm, and the angle with it in the plan is in the range of 115-130 °, and at the same time, the through hole of the elongated additional segment of the plates for fixation of the bone with the possibility of bending and torsion has an internal screw thread.

At the same time, there are risks in the device on the surface of the elongated additional segment of the plates for fixing the bone.

In this case, the distance between the risks in the device is 1 mm.

This set of general and particular essential features is necessary and sufficient for any implementation of the invention.

As noted above, the technical result of the invention consists in optimizing the design of the device, reducing the risk of breakage, increasing the reliability of osteosynthesis and, as a result, improving the conditions for the operation, while reducing the risk of surgical and postoperative complications.

In general, the technical result achieved in the implementation of the developed device consists in a sharp increase in the number of successful operations, as a result of optimizing both the design of the device as a whole and the design of its individual elements: plates and screws, in reducing the risk of breakage of the device, increasing the reliability of the connection and, as a result of consequently, in reducing the trauma of the patient and improving the conditions for the operation through the use of optimal technical parameters of the device and its constituent structural elements, as well as in increasing the convenience of the surgeon during the operation in the selection of the necessary plates and the implementation of their bending.

In particular, the technical result is the result of a combination of the following features.

Due to the fact that the through holes of the base segment of the plate are threaded, and each screw head is made of a spherical shape with a screw thread on the outer surface with the ability to deviate by ±12-15° when screwing and with the possibility of forming a spatial structure after screwing, due to these features on the base segment of the plate, all screws are fixed rigidly. As a result, the screw does not fall out of the plate even if the contact of the thread of the cylindrical part of the screw with the bone is lost. The plate stays in place due to other screws, does not turn over and the bones grow together. The plate remains stably fixed. This is an insurance of structural rigidity.

Thus, if one of the screws of the plate is detached from the jaw bone, then due to the connection of the screw head with the base segment of the plate, the screw remains in the plate, does not fall out, and the exposed position of the bone will be preserved.

Simultaneously with the foregoing, the plate is made wider, which allows the base segment of the plate to take heavy loads and make the base segment of the plate longer. This also contributes to the expansion of the range of thickness of the plates, as well as the diameters of the through holes in it for screws of a larger diameter.

The division of the plates according to the degree of rigidity further increases the versatility of the device, its reliability and ease of use of both the entire device as a whole and its individual elements: plates and screws.

The invention has developed several modifications of the presented technical solution. The optimal technical solutions of the set technical problem are presented below.

According to the invention, it is desirable that a plate of low rigidity be used for installation on the upper jaw. It withstands several adaptive bends for a better fit.

Plates of medium and high rigidity are preferably used for installation on the lower jaw. This increases the stability of osteosynthesis. It is also advisable to install plates of low rigidity on the lower jaw if there are appropriate conditions, for example, small loads and the need for several adaptive bends for better fitting.

For ease of use of plates, it is desirable that plates of different hardness have different color markings, for example, plates of low hardness are colored blue, and plates of medium and high hardness are green.

For ease of manufacture and ease of use during the operation, it is advisable that the screw thread on the cylindrical part of the screw smoothly merge into the screw thread on the surface of the screw head.

At the same time, it is preferable, in order to increase convenience when tightening the screws, that the head of each screw has a cross slot for a screwdriver and the grooves of the cross slot are made with a concave surface in the shape of a circle with a recess at the intersection. This will dramatically reduce the risk of the screwdriver cutting off the slots when screwing in and at the same time reduce the overall height of the screw head, allowing you to screw the screw into the plate hole without protruding its head above the plate surface, and the presence of a recess, for example, a cylindrical one, at the intersection of the grooves of the slots facilitates the centering of the screwdriver when screwing.

It is advisable for navigation, orientation and control of the diastasis distance during osteosynthesis of osteotomized jaw fragments, so that there are risks on the surface of the base segment of the plate, the distance between which, for example, is 1 mm.

To unload the base segment of the plate in the places where the screws are placed, to reduce torques, it is desirable that the plate, in addition to the base segment, would have at least one additional segment of the plate, designed for optimal redistribution of stresses in the base segment of the plate, with the possibility of bending and torsion and with a through hole on the end part for screwing in the screw, which in plan departs from the part of the base segment of the plate with a through hole, and the through hole in the additional segment of the plate, designed for optimal redistribution of stresses in the nodes of the base segment of the plate, has an internal screw thread, and each screw head is made with an external screw thread with the ability to deviate during screwing by ±12-15° and with the possibility of forming a reliable spatial structure after screwing.

To increase the reliability of the connection and additional convenience in the operation, it is advisable that the plate, in addition to the base segment, would have at least one elongated additional segment of the plate for fixing the bone with the possibility of bending and torsion and with a through hole on the end part for screwing screw, which in the plan departs from the part of the base segment of the plate with a through hole, and its length from the center of its through hole to the center of the nearest through hole on the base segment of the plate is 12-14 mm, and the angle with it in the plan is in the range of 115°-130 °, and at the same time, the through hole of the elongated additional segment of the plate for fixing the bone with the possibility of bending and torsion has an internal screw thread, and each screw head is made with an external screw thread with the ability to deviate when screwed by ±12-15° (that is, by angle from 12 to 15 degrees in opposite directions) and with the possibility of forming a spatial structure after screwing.

It is also desirable, to improve the convenience of navigation, orientation and control of the distance of diastasis during osteosynthesis of osteotomized jaw fragments, so that on the surface of the elongated additional segment of the plate there would be risks, the distance between which, for example, is 1 mm, as is the case on the base segment of the plate.

Another advantage of the claimed device is the possibility of its manufacture on equipment that is currently widely used in the medical industry.

As a general conclusion, it should be noted that as a result of the combination of the above features, conditions are created for a general improvement in the quality of osteosynthesis and a reduction in the patient's rehabilitation time.

Numerous other modifications of the claimed device are possible.

The invention is illustrated by drawings.

In FIG. 1 schematically shows a pair of jaw bone fragments with a callus between them, the pair of jaw bone fragments being fixed by the base segment of the plate, while the schematically shown plate is attached to each jaw bone fragment by pairs of screws with screw threads on the cylindrical part and screw threads on the surface of the screw head, moreover, one screw is shown deviated from the perpendicular to the surface of the jawbone fragment at an angle α(α=±12-15°), perspective view;

In FIG. 2 depicts a screw, perspective view,

In FIG. 3 shows a straight in plan base segment of a plate made of pure titanium 1 mm thick of low rigidity for the lower jaw, with a pair of additional plate segments designed for optimal stress redistribution in the base segment of the plate, with the possibility of bending and torsion and with a through hole at the end of each of them for screwing in a screw, which, in plan, depart from the corresponding part of the base segment of the plate with a through hole, plan view;

In FIG. 4 is the same section A-A of Fig. 3;

In FIG. 5 shows a rectilinear plate of an alloy with a thickness of over 1.5 mm of high rigidity for the lower jaw, containing a base segment with a pair of additional segments designed for optimal redistribution of stresses in the plate, with the possibility of bending and torsion and with a through hole at the end of each of them for screwing in screws, which, in plan, depart from the corresponding part of the base segment of the plate with a through hole, plan view,

In FIG. 6 - the same section B-B of Fig. 5;

In FIG. 7 shows an arcuate plate made of pure titanium 2 with a thickness of 1 mm of low rigidity for the lower jaw, containing an arcuate base segment and a pair of additional segments designed for optimal redistribution of stresses in the base segment of the plate, with the possibility of bending and torsion and with a through hole in the the end part of each of them for screwing in screws, which in plan depart from the corresponding part of the base segment of the plate with a through hole, plan view,

In FIG. 8 is the same section B-B of FIG. 7;

In FIG. 9 shows an arcuate plate of an alloy with a thickness of over 1.5 mm of high rigidity for the lower jaw, containing an arcuate base segment with a pair of additional segments designed for optimal redistribution of stresses in the base segment of the plate, with the possibility of bending and torsion and with a through hole on the end part of each of them for screwing in screws, which, in plan, depart from the corresponding part of the base segment of the plate with a through hole, plan view,

In FIG. 10 - the same section Г-Г of Fig. 9;

In FIG. 11 shows a straight-line plate made of pure titanium with a thickness of 1 mm of low rigidity for the upper jaw, containing a base segment with a pair of additional segments designed for optimal stress redistribution in the base segment of the plate, with the possibility of bending and torsion and with a through hole at the end of each of them for screwing in the screw, which in the plan depart from the corresponding part of the base segment of the plate with a through hole, a feature of this plate is that this plate is left (that is, one of the additional segments is oriented to the left), view in plan;

In FIG. 12 - the same section D-D of Fig. eleven;

In FIG. 13 shows a straight-line plate made of pure titanium with a thickness of 1 mm of low rigidity for the upper jaw, containing a base segment with a pair of additional segments designed for optimal stress redistribution in the base segment of the plate, with the possibility of bending and torsion and with a through hole at the end of each of them for screwing in the screw, which in the plan depart from the corresponding part of the base segment of the plate with a through hole, a feature of this plate is that this plate is right (that is, one of the additional segments is oriented to the right), view in plan;

In FIG. 14 is the same section E-E of FIG. 13;

In FIG. 15 shows an arc-shaped plate made of an alloy 1 mm thick of medium hardness for the lower jaw, and the plate has an arcuate base segment and two pairs of additional segments designed for optimal redistribution of stresses in the base segment of the plate, with the possibility of bending and torsion and with a through hole at the end parts of each of them for screwing in screws, which, in plan, depart in pairs from their respective different parts of the base segment of the plate with a through hole, plan view,

In FIG. 16 - the same section F-F of FIG. 15;

In FIG. 17 shows an arcuate plate of an alloy with a thickness of over 1.5 mm of high rigidity for the lower jaw, and the plate has an arcuate base segment and two pairs of additional segments designed for optimal redistribution of stresses in the base segment of the plate, with the possibility of bending and torsion and with a through a hole on the end part of each of them for screwing in the screws, which in the plan in pairs depart from the corresponding different parts of the base segment of the plate with a through hole, plan view;

In FIG. 18 is the same I-I section of FIG. 17;

In FIG. 19 shows a plate rectilinear in plan, and the plate has a base segment and a pair of additional segments designed for optimal redistribution of stresses in the base segment of the plate, with the possibility of bending and torsion and with a through hole at the end of each of them for screwing in screws that move away in plan from the corresponding part of the base segment of the plate with a through hole, with the possibility of bending and torsion, and in addition, the plate has one elongated additional segment for fixing the bone with the possibility of bending and torsion and with a through hole on the end part for screwing in the screw, which in plan departs from parts of the base segment of the plate with a through hole, a feature of this plate is that this plate is right (that is, the elongated additional segment is oriented to the right), plan view, axonometry;

In FIG. 20 - the same, plan view,

In FIG. 21 - the same section K-K of Fig. 20;

In FIG. 22 shows a plate rectilinear in plan, and the plate has a base segment and a pair of additional segments designed for optimal redistribution of stresses in the base segment of the plate, with the possibility of bending and torsion and with a through hole at the end of each of them for screwing in screws that move away in plan from the corresponding part of the base segment of the plate with a through hole, with the possibility of bending and torsion, and in addition, the plate has one elongated additional segment for fixing the bone with the possibility of bending and torsion and with a through hole on the end part for screwing in the screw, which in plan departs from parts of the base segment of the plate with a through hole, a feature of this plate is that this plate is left (that is, the elongated additional segment is oriented to the left), plan view, axonometry;

In FIG. 23 is the same L-L section of FIG. 20;

In FIG. 24 shows the screw from the side of the head, perspective view.

The device for maxillofacial surgery and surgical dentistry includes a plate 1 with the ability to bend and twist it with the help of hands or a tool, for example, pliers, designed for fixation to the bone surface, containing at least a base segment 2, having at least , a pair of through holes 3 for screws in the base segment on the sides, and screws 4 designed for screwing into the bone 5 of the lower and/or upper jaw and fixing the plate 1 to the surface of the bone 5 (Fig. 1). Through holes 3 in the base segment 2 of the plate 1 are made with an internal screw thread 6, and each head 7 of the screw 4 is made with an external screw thread 8 with the ability to deviate when screwing at an angle "α" in the range from 12° to 15° in any direction from the central longitudinal axis of the through hole 3 with the possibility of forming a reliable spatial structure after screwing, and the base segment 2 of the plate 1 is characterized by the following parameters:

• the width of the base segment 2 of the plate is from 2.8 to 4.5 mm, while the width of the base segment means the distance between the sides of the base segment in the cross section in its middle part;

• the diameter of the through holes 3 on the sides of the base segment 2 of the plate is in the range from 5 to 7 mm,

• the thickness of the base segment 2 of the plate is selected in the range from 0.8 to 2.2 mm,

while the base segment 2 of the plate 1 is made either rectilinear in plan or arcuate in plan and its length between the axes of its adjacent through holes 3 closest to the center lies in the range from 11 to 30 mm.

In addition, the plate 1 has different rigidity: low, medium and high, and the plate 1 of low rigidity is characterized by being made of pure titanium, for example, TiCP Grade 2 ASTM F67-13 (similar to BT1-0 GOST 22178), and has thickness is not more than 1 mm, a plate of medium hardness is characterized by the fact that it is made of a titanium-aluminum-vanadium alloy, for example, Ti-6Al-4V ELI ASTM F136-13 alloy (similar to VT6 GOST 19807), and has a thickness of 1 mm to 1 .5 mm, a high rigidity plate is characterized by the fact that it is made of a titanium-aluminum-vanadium alloy, for example, Ti-6Al-4V ELI ASTM F136-13 alloy (analogue of VT6 GOST 19807), and has a thickness of over 1.5 mm, and plate 1 with a thickness of 1 mm or less has a rectangular cross section, and with a thickness of more than 1 mm it has a cross section with roundings to the sides.

As noted above, the through holes 3 in the base segment 2 of the plate 1 are made with an internal screw thread 6, and each head 7 of the screw 4 is made with an external screw thread 8.

As shown in FIG. 1 internal screw thread 6 is located in the upper expanded part 9 of the through hole 3. After complete screwing, the head 7 of the screw 4 rests against the annular ledge 10 inside the through hole 3 of the plate 1. At the same time, the screw thread 11 on the cylindrical part 12 of the screw is screwed into the bone 5 of the lower and/or upper jaw. As a result, the screw 4 in the through hole 3 of the plate 1 is connected to the plate 1 independently and, in addition, the screw is connected to the bone 5. All screws 4 are rigidly fixed to the plate 1. If any screw 4 for some reason is disconnected from any bone 5 of the jaw , then due to the connection of the head 7 of the screw 4 with the plate 1, the position of the plate 1 on the surface of the bone 5 will be preserved, since the screw 4 remains in the plate 1 and does not fall out. As a result, screw 4 does not come out of plate 1, plate 1 remains in place, does not turn over, and the bones grow together. Plate 1 is stably fixed. This is an insurance of structural rigidity.

It is important to note that the screw thread 11 on the cylindrical part 12 of the screw 4 smoothly passes into the screw thread 8 on the side surface 13 of the head 7 of the screw 4.

Thus, the screw thread 11 on the cylindrical part 12 of the screw 4 is screwed into the bone 5, and the external screw thread 8 on the side surface 13 of the head 7 is screwed into the internal screw thread 6 located in the upper expanded part 9 of the through hole 3 of the plate 1, providing a rigid cantilever construction (plate-screw). If the connection of the cylindrical part 12 of the screw 4 with the bone 5 is lost, the screw 4 will not fall out.

NOTE: connection of screw 4 with plate 1 and bone 5 is carried out on any segment of the plate: base segment 2, additional segment of the plate, extended additional segment of the plate.

An important feature is that the screw 4 has the ability to deviate during screwing at an angle "α" in the range from 12 to 15° with the possibility of forming a reliable spatial structure after screwing (Fig. 1). To do this, the internal screw thread 6 is located in the upper expanded part 9 of the through hole 3 of the plate 1, and the screw head may have a spherical shape. This creates additional convenience during the operation, allowing the surgeon during the operation to screw the screw 4 into the bone 5 in the most optimal direction to obtain the most reliable connection with the bone 5, for example, a bone fragment, and as a result forming a reliable spatial structure of the plate 1 and screwed 4 screws in it.

Thus, if in the analog the screw could become loose, fall out of the bone, and the structure eventually lost its rigidity, and later it could rotate around the remaining screws, as a result of which the occlusion plane left, then this does not happen in the claimed invention.

As noted above, along with the above features, the plate 1 is characterized by the following parameters: the width of the base segment 2 of the plate is 2.8-4.5 mm, which allowed the base segment 2 of the plate 1 to take heavy loads and make the base segment 2 of the plate 1 longer (see Fig. Fig. 1). Previously (see closest analogue), the width of the base segment of the plate was 2.2 mm.

Another feature of the claimed invention is that the diameters of the through holes 3 (diameters of the "lugs") on the sides of the base segment 2 of the plate 1 have increased. They are in the range of 5-7 mm, depending on the load at the places of fastenings with screws 4 the same and equal to 4.5 mm). The ability to make a larger diameter appeared after the base segment 2 of the plate 1 began to be made wider. The larger diameter of the through holes 3 made it possible to screw in screws 4 of a larger size and, consequently, to take large loads with the plate 1.

The peculiarity also lies in the fact that the range of thicknesses of the base segment of the plate 1 has expanded from 0.8 to 2.2 mm. This parameter is shown, for example, in Fig. 4, fig. 6, fig. 8, and is indicated by the position 14. Previously, it was constant and equal to 1 mm. The expansion of the thickness range allows during the operation to select the thickness of the base segment 2 of the plate 1 depending on the load applied to it.

The increase in the width of the base segment 2 of the plate 1, as well as its thickness 14, allowed the base segment 2 of the plate 1 to perceive a large applied load and not bend spontaneously. This made it possible to increase the length of the base segment of the plate 1 between the centers of its through holes 3 on the sides of the base segment of the plate 1 in the range from 11 to 30 mm (previously this distance was constant and equal to 15 mm).

The base segment 2 of the plate 1 can be made either rectilinear in plan and its length between the axes of its adjacent holes 3 adjacent to the center of the base segment of the plate 1 is 11-30 mm, depending on the operating conditions, loads, thickness of the plate and the metal from which it is made ( Fig. 3 - Fig. 6, Fig. 11 - Fig. 14, Fig. 19, Fig. 22 - Fig. 23), or is made arcuate in plan and its length between the axes of its adjacent holes closest to the center is 11-30 mm ( for installation on the lower jaw along the edge of Fig. 7 - Fig. 12; Fig. 15 - Fig. 18). The increase in the length of the base segment of the plate 1 made it possible to further move the bone fragments of the bone 5, that is, it made it possible to increase the stability of osteosynthesis of the bone 5 with a significant movement of the osteotomized bone segment. Such a range of loads, which as a result of the invention can be perceived by the base segment 2 of the plate 1, dramatically increases the convenience of the operation, since it allows the surgeon to choose a more suitable plate 1, which is necessary for installation in this particular case, both in terms of the magnitude of the load applied to it, and in terms of other parameters (installation features, installation location, etc.).

At the same time, to further increase the number of successful operations and ease of use of the plate 1, three degrees of rigidity of the plate 1 (in terms of softness and ease of bending) were introduced: low, medium, and high.

In this case, the plate 1 of low rigidity is characterized by the fact that it is made of pure titanium, for example, TiCP Grade 2 ASTM F67-13 (similar to VT1-0 GOST 22178) and has a thickness of not more than 1 mm (see Fig. 3 - Fig. 4, Fig. 7 - Fig. 8, Fig. 11 - Fig. 14). It can be used both for operations on the upper jaw and for operations on the lower jaw.

At the same time, plates of low rigidity are used for the upper jaw, allowing several adaptive bends to be made for a better fit to the bone surface.

The plate 1 of medium hardness is characterized by the fact that it is made of a titanium-aluminum-vanadium alloy, for example, Ti-6Al-4V ELI ASTM F136-13 alloy (similar to VT6 GOST 19807, and has a thickness of 1 to 1.5 mm inclusive (Fig. 15 - Fig. 16. Plate 1 with this type of rigidity is used only for installation on the lower jaw.

The plate 1 of high rigidity is characterized by the fact that it is made of a titanium-aluminum-vanadium alloy and has a thickness of over 1.5 mm (Fig. 5 - Fig. 6, Fig. 9 - Fig. 10, Fig. 15 - Fig. 18). Plate 1 with this type of rigidity is used only for installation on the lower jaw and for fixing complex bone autografts with the inclusion of the fibula when eliminating jaw defects using microsurgical techniques.

An important feature of the claimed invention is that the base segment 2 of the plate 1 with a thickness of 1 mm or less has a rectangular cross section (Fig. 4, Fig. 8, Fig. 12, Fig. 14, Fig. 16), and the base segment 2 plate 1 with a thickness of more than 1 mm has a cross section with rounding 15 to the side in cross section (Fig. 6, Fig. 10, Fig. 18). The rounding in the cross section from the middle of the base segment 2 of the plate 1 makes the base plate 1 less noticeable under the skin, in addition, it has become more comfortable for the doctor to work during the operation (better and easier to bend the plate 1).

A feature of the claimed invention also lies in the fact that, as noted earlier, the plate 1 of low rigidity is intended for installation, as a rule, on the upper jaw (they require a lot of bending) (see Fig. 3 - Fig. 4, Fig. 7 - Fig. 8, fig. 11 - fig. 14), and the plate 1 of low, medium and high rigidity is intended for installation on the lower jaw.

Another feature of the claimed invention is that plates of different stiffness have different color markings. For example, a low hardness plate can be painted blue, while a medium and high hardness plate can be painted green.

Previously, there was a different color scheme: the short plate was marked in yellow, and the long plate was blue. Thus, the length of the plate was previously characterized by color, which is less convenient.

In the claimed invention, color characterizes the material and thickness of the plate, and, consequently, the degree of rigidity of the plate.

1. A plate of low rigidity (soft plate), made of pure titanium and having a thickness of up to 1 mm, has, as noted above, a blue color, and a plate of medium and high rigidity, made of an alloy and having a thickness of 1 mm, have a green color . This increases the convenience of the choice of the plate for the surgeon during the operation.

The bending and fitting of the segments of the plate 1 is carried out with special tools - benders. The bending of the plate segments 1 should not pass through the through hole 3, since a screw is screwed into it during the operation. If it is necessary to bend plate 1 near the hole, then it is advisable to use two benders, with one tool covering and clamping the hole, and with the other, the plate segment 1 is bent near hole 3.

As noted earlier, for ease of manufacture and ease of use of the plate during the operation, it is advisable that the screw thread 11 on the cylindrical part 12 of the screw 4 would smoothly pass into the screw thread 8 on the side surface 13 of the head 7 of the screw 4.

At the same time, it is preferable, in order to increase convenience when screwing screws, that on the head 7 of each screw 4 there would be a cross-shaped slot 16 for a screwdriver and the grooves 17 of the cross-shaped slot 16 would be made with a concave surface in the shape of a circle (Fig. 2, Fig. 24).

This will dramatically reduce the risk of the screwdriver cutting off the slot when screwing and at the same time reduce the overall height of the head 7 of the screw 4, making it less noticeable from under the skin. The presence of recess 18 at the intersection of the grooves 17 of the cross slot 16 facilitates the centering of the screwdriver when screwing (Fig. 24).

For navigation and orientation of the osteotomy, it is advisable that on the surface of the base segment 2 of the plate 1 there would be risks 19, the distance between which, for example, is 1 mm (Fig. 19). The marks 19 are designed to increase the ease of use of the plate 1, using them, for example, as guidelines in which places it is necessary to bend the base segment 2 of the plate 1.

To unload the base segment 2 of the plate 1 in the places where the screws 4 are placed, to reduce torques, it is desirable that the plate 1, in addition to the base segment 2, would have at least one additional segment 20 designed for optimal redistribution of stresses in the base segment of the plate 1, with the possibility of bending and torsion, and with a through hole 21 on the end part for screwing in the screw 4, which in plan departs from the part of the base segment 2 of the plate 1 with a through hole 3, and the through hole 21 in the additional segment 20 of the plate 1 has an internal screw thread 22, and each head 7 of the screw 4 is made with an external screw thread 8 with the ability to deviate during screwing by ±12-15° and with the possibility of forming a spatial structure after screwing (in this case, the explanations are similar to those given above for the base segment 2).

To increase the convenience of connecting bone fragments 5, it is advisable that the plate 1, in addition to the base segment 2, would have at least one elongated additional segment 23 for fixing the bone 5 with the possibility of bending and torsion and with a through hole 24 on the end part for screwing screw 4, which in plan departs from the base segment of the plate 1 with a through hole 3, and its length from the center of its through hole 24 to the center of the nearest through hole 3 on the base segment 2 of the plate lies in the range from 12 mm to 14 mm, and the angle ( 3 with it in the plan is in the range of 115°-130°, and at the same time, the through hole 24 of the elongated additional plate 23 for fixing the bone with the possibility of bending and torsion has an internal screw thread 25, and each screw head 4 is made with an external screw thread with the possibility deviate during screwing by ± 12-15 ° and with the possibility of forming a spatial structure after screwing (Fig. 19).

It is also desirable, for navigation and orientation of the osteotomy, that on the surface of the extended additional segment of the plate 23 for fixing the bone with the possibility of bending and torsion there would be marks 26, the distance between which is 1 mm. These risks, as described above for the base segment 2 of the plate 1, are here again intended to increase the usability of the plate 1, using them, for example, as guidelines in which places it is necessary to fold the plate 1. For example, first the base segment 2 of the plate 1 is not bent. an elongated additional segment 23 is applied to the place of the future location and the places are marked in which, for example, the base and elongated additional segments must be bent, remembering them according to the risks. Then, taking the base segment 2 of the plate 1 with an elongated additional segment 23 from the installation site, they are bent, for example, by hand, focusing on the risks, and then the plate is applied to the installation site to check the accuracy of the bends, and if the result is positive, the curved plate 1 is attached to the bone 5 screws 4.

The Applicant considers it necessary to note that 4 are of the same design. Through holes and screws are shown in detail when analyzing the design of the base segment in the base segment, in the additional segment and in the elongated additional segment, identical through holes are made, which have upper expanded parts with an annular ledge inside each through hole, and inside the through hole there is a screw thread. In the claimed device, screws are used everywhere. In the additional segment and in the extended additional segment, a similar design is used without detailed analysis, so as not to repeat and not overload the drawings.

The use of the claimed device is carried out as follows:

Orthodontic preparation of the operation is performed in a hospital under anesthesia by a team of three maxillofacial surgeons.

During the operation, general anesthesia is performed - anesthesia, incisions are made from the side of the oral cavity (intraoral access, without external incisions on the skin of the face).

Further, with the help of bone saws and instruments, thin (0.5 mm) cuts of tooth-containing fragments of the jaws are carried out, followed by osteotomy (artificial fracture along the cut lines) to carry out their movement.

Movement of the jaws is carried out strictly in accordance with the operation plan and thanks to intraoperative templates made individually by the surgeon and orthodontist at the stage of operation planning.

Sawn fragments of jaw bones 5 are fixed with plates 1 and screws 4.

An average of four plates are installed on the upper jaw and two plates on the lower jaw on each side. Each of the plates 1 is fixed by screwing screws 4 into its through holes 3, 21, 24.

In the future, they can be removed 6 months after the operation and the completion of the formation of callus 2 (Fig. 1).

The end of the operation is the suturing of the incisions in the oral cavity. After two weeks, the surgeon or his assistant will remove the stitches at an outpatient appointment at a scheduled examination after discharge from the hospital.

Below the Applicant considers it necessary to provide a more detailed description of the use of the claimed invention in treatment.

After orthodontic preoperative preparation, orthognathic surgery is planned.

1. Stage of treatment planning.

A virtual computer simulation of an orthognathic operation is carried out, taking into account the increase in the volume of the respiratory spaces of the pharynx. For this, a 3-dimensional cephalometric analysis of the reconstruction of computed tomography of the patient's head is performed (Arnett G.W. Facial and dental planning for orthodontists and oral surgeons. // Santa Barbara, California. - 2004. P. 151-164.)

The soft tissue contour of the face profile, bones of the skeleton and teeth are identified on the obtained model. To identify the soft tissue contour of the face, a 3D photograph of the patient's head in the true position is superimposed on the soft tissue contour of the CT scan of the patient's head, determining the central line of the face, the degree of sagittal disproportions, as well as vertical and axial asymmetries.

Cephalometric landmarks are applied to the model (points projected onto the soft tissue contour and onto the bone structures of the skeleton and teeth).

When planning an operation on a face model, the movement of the specified points and angle is simulated until certain values are reached, thereby obtaining an operation model:

- the extension of the Pog' point is carried out in the sagittal plane relative to the true vertical line of the face (IVL) to the position of "-0.7" mm in women (-2.6 +/- 1.9 mm normal values and standard deviation in the Arnett/McLaughtin cephalometric analysis) and "-1.7 » mm in men (-3.5 +/- 1.8 mm normal values and standard deviation in Arnett/McLaughtin cephalometric analysis). This leads to an aesthetically correct position of the chin and lower lip;

- the extension of the M × I point is also carried out in the sagittal plane relative to the ventilator to the position of "-7" mm in women (-9.2 +/- 2.2 mm normal values and standard deviation in the Arnett/McLaughlin cephalometric analysis) and "-10.3" mm in men (-12.1 +/- 1.8 mm normal values and standard deviation in Arnett/McLaughlin cephalometric analysis).

This results in an aesthetically correct position of the upper jaw and upper lip.

- change the angle of their OR in relation to the ventilator to a position of 93.8° in women (-95.6+/-1.8° normal values and standard deviation in Arnett/McLaughlin cephalometric analysis) and 93.6° in men (95.0 +/- 1.4° normal values and standard deviation in Arnett/McLaughlin cephalometric analysis). This results in an aesthetically correct position of the upper jaw and upper lip in relation to the position of the chin and lower lip, as well as in relation to facial proportions in general.

During the contour planning of the operation, the movement of osteotomized fragments of the upper and lower jaws is simulated, taking into account the restoration of the correct bite, the normalization of the aesthetic proportions of the face and the restoration of facial symmetry.

Further, based on the virtual 3D movements of the osteotomized fragments of the upper and lower jaws, a bite template is designed and made. This template is built on the basis of 3D computer modeling and subsequent printing on a 3D printer.

2. Stage of operation

Orthognathic surgery is performed in a hospital under endotracheal anesthesia and consists of bilateral sagittal osteotomy of the lower jaw and osteotomy of the upper jaw at the level of Le Fort I with maxillo-mandibular extension to a distance determined by an intraoperative bite template made as a result of virtual computer simulation of this operation.

The technique of the operation of bilateral sagittal osteotomy of the lower jaw:

After treatment of the oral cavity with an antiseptic solution and preliminary hydropreparation in the region of the transitional fold of the lower jaw of the submucosal and subperiosteal space with a solution of an anesthetic of the articaine series with a vasoconstrictor, an S-shaped incision of the mucous membrane is performed in the retromolar region in front of the posterior from the first molar below the border of the attached gum to the projection of the base of the coronoid process . The surface of the body of the lower jaw is skeletonized from the first molar to the angle of the lower jaw from the outside and the inner surface of the branch above the tongue to a height of 1 cm from the anterior to the posterior edge of the branch. On the inner side of the branch, a “tongue” is visualized - the entry point of the lower alveolar nerve. An osteotomy of the inner cortical plate of the lower jaw branch is performed, retreating from the uvula upwards by about 1 cm. Further, the osteotomy is continued parallel to the oblique line of the lower jaw. In the region of the 36th tooth, a vertical cut of the outer cortical plate is performed. A similar operation is performed on the opposite side. Carry out hemostasis. Then the osteotomized fragments of the lower jaw are split. The tooth-containing fragment of the lower jaw is moved forward relative to the upper jaw and placed on an intraoperative bite template, modeled as a result of virtual computer simulation of this operation. Manual positioning of the condylar processes of the temporomandibular joints is carried out in a central ratio, followed by rigid fixation of the mandibular fragments on the left and right with titanium miniplates according to the present invention. Carry out hemostasis. Wounds are sutured with monofilament 4/0, 5/0.

Operation technique: osteotomy of the upper jaw at the level of Le Fort I.

After treating the surgical field with an antiseptic solution and preliminary hydropreparation in the region of the transitional fold of the upper jaw of the submucosal and subperiosteal space with a solution of an anesthetic of the articaine series with a vasoconstrictor at a dilution of 1: 200,000, an incision is made 0.5 cm away from the attached gum from 15 to 25 teeth, the anterior surface is skeletonized upper jaw.

An osteotomy of the upper jaw is performed at the level of Le Fort I, followed by mobilization of the osteotomized tooth-containing fragment. The level of the proposed osteotomy is determined 5 mm above the apexes of the maxillary teeth.

The osteotomized fragment is mobilized, moved forward and set in a constructive occlusion with intermaxillary binding, fixing with ligatures for braces with a mandibular tooth-containing fragment, and then this fragment is osteosynthesised with titanium Y and L-shaped miniplates.

Diastases between osteotomized bone fragments are replaced by autologous bone.

Carry out hemostasis. Wounds are sutured with monofilament 4/0, 5/0. During the operation, a device according to the claimed invention was used.

Postoperative orthodontic treatment is carried out in order to stabilize the bite within 6-12 months after the operation and ends with the manufacture of a retainer.

We examined, prepared for surgery and operated using plates and screws, according to the claimed invention, 10 patients aged 18 to 55 years with a complete growth of the facial skeleton.

Example.

Patient A, diagnosis: Combined jaw deformity, upper and lower retrognathia.

Simulated: advancement of the maxillary fragment in the sagittal plane by 11 mm at the M×I point, the mandibular fragment by 16 mm at the Pog' point with a 9° counterclockwise rotation of the occlusal plane

Bimaxillary orthognathic surgery was performed in the volume of bilateral sagittal osteotomy of the lower jaw and osteotomy of the upper jaw at the Le Fort level with the displacement of the osteotomized fragments into position according to the operating plan, followed by osteosynthesis with titanium screws and plates, in full accordance with the claimed invention.

Results achieved:

- protrusion of the lower jaw at the Pog' point in the sagittal plane relative to the true vertical line of the face was 15 mm. This resulted in an aesthetically correct position for the chin and lower lip.

- the extension of the M×I point is also carried out in the sagittal plane relative to the IVL was 11 mm. This resulted in an aesthetically correct position of the upper jaw and upper lip.

- rotation of the occlusal plane of the jaws counterclockwise led to an aesthetically correct position of the upper jaw and upper lip relative to the position of the chin and lower lip, as well as relative to the facial proportions in general.

EFFECT: invention makes it possible to optimize both the design of the device as a whole and the design of its individual elements: plates, segments and screws, reduce the risk of device breakage, increase the percentage of successful operations, increase the reliability of osteosynthesis and reduce the patient's rehabilitation time.

Sources of information taken into account:

1. Patent for a utility model of the Russian Federation No. 201594, class. A1C 8/00, 05/07/2020;

2. RF patent for the invention No. 2558999, А61В 17/24, 07/28/2014;

3. Safyanova Elena Viktorovna DEVELOPMENT AND CLINICAL SUBSTANTIATION OF A NEW SURGICAL METHOD FOR THE TREATMENT OF CONGENITAL JAW DEFORMATIONS 14.01.14 "Dentistry" Dissertation for the degree of Candidate of Medical Sciences, Federal State Budgetary Educational Institution of Higher Professional Education "Nizhny Novgorod State Medical Academy" of the Ministry of Health Russian Federation on rights of the manuscript, Nizhny Novgorod - 2018, p. 80, fig. 3.19.b) (closest analogue).

Claims (10)

1. A device for maxillofacial surgery and surgical dentistry, including a plate with the possibility of bending and torsion, designed for fixation to the bone surface, containing at least a base segment having at least a pair of through holes for screws in the base segment on the sides, and screws designed for screwing into the bone and fixing the plates to the surface of the bone, characterized in that the plate has different rigidity: low, medium and high, and the plate of low rigidity is characterized by the fact that it is made of pure titanium and has a thickness of up to 1 mm, the plate of medium rigidity is characterized by being made of a titanium-aluminum-vanadium alloy and has a thickness of 1 to 1.5 mm inclusive, the plate of high rigidity is characterized by being made of a titanium-aluminum-vanadium alloy and has a thickness of over 1 .5 mm, moreover, the plate with a thickness of 1 mm has a rectangular cross section, and the plate with a thickness of more than 1 mm has a cross section with roundings to the sides, while the through holes in the base segment of the plates are made with an internal screw thread, while the screw is made as follows that each screw head is made with an external screw thread on the side surface, the head of each screw has a cross-shaped slot for a screwdriver, and the screw is made with the ability to deviate when screwing at an angle of 12 to 15 degrees in opposite directions from the central longitudinal axis of the through hole, and the screw thread on the cylindrical part of the screw smoothly turns into the external screw thread on the side surface of the screw head with the possibility of forming a reliable spatial structure after screwing in, and the base segment of the plates is characterized by the following parameters: the width of the base segment of the plates is 2.8-4.5 mm, the diameter of the through holes on the sides of the base segment of the plates 5-7 mm, the thickness of the base segment of the plates is 0.8-2.2 mm, while the base segment of the plates is made either straight in plan or arcuate in plan and its length between the axes of its adjacent through holes closest to the center 11-30 mm. 2. The device according to claim. 1, characterized in that the plate of low rigidity is intended for installation on the upper jaw, and the plate of low, medium and high rigidity is intended for installation on the lower jaw. 3. The device according to claim. 1, characterized in that the degree of rigidity of the plate - small, medium and high is characterized by color marking. 4. The device according to claim 1, characterized in that the screw head has a cross slot for a screwdriver, the slots of the cross slot are made with a concave surface in the shape of a circle and have recesses at the intersection. 5. The device according to claim 1, characterized in that there are risks on the surface of the base segment of the plate. 6. The device according to claim 6, characterized in that the distance between the risks is 1 mm. 7. The device according to claim 1, characterized in that the plate, in addition to the base segment, has at least one additional plate segment designed for optimal stress redistribution in the base segment of the plates with the possibility of bending and torsion and with a through hole at the end parts for screwing in a screw, which in plan extends from a part of the base segment of the plates with a through hole, and the through hole in the additional segment of the plates, designed for optimal redistribution of stresses in the nodes of the base segment of the plates, has an internal screw thread. 8. The device according to claim 1, characterized in that the plate, in addition to the base segment, has at least one elongated additional plate segment for fixing the bone with the possibility of bending and torsion and with a through hole on the end part for screwing in the screw, which in the plan it departs from the part of the base segment of the plate with a through hole, and its length from the center of its through hole to the center of the nearest through hole on the base segment of the plates is 12-14 mm, and the angle with it in the plan is in the range of 115-130°, and at In this case, the through hole of the elongated additional segment of the plates for fixing the bone with the possibility of bending and torsion has an internal screw thread. 9. The device according to claim 8, characterized in that there are risks on the surface of the elongated additional segment of the plates for fixing the bone. 10. The device according to claim 9, characterized in that the distance between the risks is 1 mm.

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