An orthodontic anchorage pin penetration mucosa extension device and a quantitative traction control method thereof
By combining the orthodontic anchorage screw mucosal extension device with the elastic traction chain, the problem of using anchorage screws in mucosal embedding is solved, achieving precise control of traction force and improving patient comfort.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HOSPITAL OF STOMATOLOGY XIAN JIAOTONG UNIVERSITY
- Filing Date
- 2026-04-27
- Publication Date
- 2026-07-21
Smart Images
Figure CN122423972A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of orthodontic medical device technology, specifically to an orthodontic anchorage screw-through mucosal lengthening device and its quantitative traction control method. Background Technology
[0002] Orthodontic anchorage screws are temporary anchorage devices, commonly used in orthodontic treatment to provide additional anchorage force and help teeth move to their ideal positions. Orthodontic anchorage screws have a small diameter, good biocompatibility and mechanical properties, and can be implanted into the alveolar bone at any location between the tooth roots. Their implantation position and direction can be flexibly adjusted to meet the treatment needs of different patients, providing stable anchorage force to assist in anterior tooth retraction, molar distalization, molar mesialization, closing gaps, intruding teeth, and controlling the midline. They avoid unintended displacements that may occur when teeth or dental arches are used as anchorage structures, ensuring full utilization of the interdental spaces during treatment and reducing unnecessary tooth movement. At the same time, anchorage screws reduce reliance on extraoral anchorage (such as headgear) in traditional methods, reducing patient discomfort. Therefore, the use of anchorage screws can help teeth move in a predetermined direction and with predetermined force, improving orthodontic efficiency, shortening treatment time, and increasing treatment accuracy and satisfaction by providing stable anchorage.
[0003] Orthodontic anchorage screws are implanted by drilling holes in the alveolar bone. The procedure is simple, and force can be applied immediately after implantation. Orthodontists typically use elastic bands, rubber chains, nickel-titanium coil springs, elastic cords, and other force-applying attachments to connect to the neck of the anchorage screw and apply force to the teeth or dental arch being treated. However, implants placed at locations such as the lower border of the zygomatic process, the external oblique line of the mandible, or the symphysis of the mandible and chin are prone to being surrounded by overgrown soft tissue due to the thicker and more mobile mucosa in these areas. This can cause local mucosal redness, inflammation, and bleeding. During follow-up visits, the anchorage screw head needs to be exposed again when the force-applying elastic attachment is replaced because it is covered by soft tissue, which is more invasive and can easily cause pain and discomfort to the patient. Furthermore, repeated mucosal inflammation around the anchorage screw can easily lead to loosening and dislodgement. To address this issue, some doctors may choose anchorage screws with longer tips to facilitate penetration through the mucosa. However, due to the limited space inside the mouth, longer screw tips may cause traumatic ulcers on the corresponding lip and buccal mucosa, resulting in poor patient comfort. Furthermore, the significant leverage effect of longer screw tips is detrimental to the long-term stability of the anchorage screw. Some doctors also create their own ligatures, wrapping them around the implant tip and extending them from the mucosa, with the ends bent into hooks to connect to the elastic attachment. However, bending ligatures clinically is time-consuming, laborious, and inconvenient; the sharp ends of the ligatures may irritate and damage the local oral mucosa, causing traumatic oral ulcers; and the thin ligatures are prone to fatigue breakage when repeatedly bent during elastic attachment replacement, making long-term use impractical. In addition, when using elastic attachments for traction in clinical practice, judging the traction force mainly relies on the doctor's experience in counting the number of rubber chain turns or visually estimating and feeling the tension, making it difficult to accurately apply controllable traction.
[0004] To expand the traction direction or improve operational convenience, patent application CN205548730U adds radial slots or fixing grooves to the anchorage screw head cap. While this expands the force range to some extent, it still essentially remains within the scope of anchorage screw head fixation. In special implantation areas such as the lower edge of the zygomatic process, the external oblique line of the mandible, and the mandibular-mental symphysis, the anchorage screw head cap and traction accessories are easily surrounded and buried by hyperplastic soft tissue due to the thicker and more mobile local mucosa. Furthermore, some solutions attempt to expand functionality by increasing the complexity of the anchorage screw body structure. For example, invention patent CN106901848B uses a rotating universal sleeve to allow the anchorage wire to pass through the universal sleeve's wire-passing hole and be positioned arbitrarily, allowing two or more anchorage screws to be used simultaneously to pull the same anchorage wire. However, this type of "heavy equipment" solution faces multiple challenges in clinical application: First, the complex mechanical structure requires extremely high precision in chairside operation, and the small parts such as fastening screws increase the operation time and the risk of parts falling off; second, the complex metal parts located in the soft tissue active area are not only dead corners for plaque accumulation, but also easily cause traumatic ulcers of the lip and cheek mucosa. It has not fundamentally solved the technical deadlock of the difficulty in replacing attachments in deeply buried areas, and lacks a systematic implementation path for the most core "quantitative control of force value" in orthodontic force application. Summary of the Invention
[0005] To overcome the shortcomings of the existing technologies, the present invention aims to provide an orthodontic anchorage screw mucosal extension device and its quantitative traction control method, which effectively solves the problem of using or replacing elastic force-applying attachments when anchorage screws are embedded in soft tissue, reduces the incidence of traumatic oral ulcers and peri-anchorage screw mucositis during orthodontic treatment, improves treatment efficiency and patient comfort, and determines the required length of the chain rubber band based on the mechanical test results of the elastic traction segment and the actual clinical traction distance, thereby achieving controllable and precise application of traction force.
[0006] To address the aforementioned problems, the present invention provides the following technical solution: An orthodontic anchorage screw mucosal extension device includes a connecting sleeve and a traction part; the traction part includes an extension traction chain and a traction hook connected to one end of the extension traction chain, the other end of the extension traction chain is connected to the connecting sleeve, and the connecting sleeve is pre-fixed to the neck of the orthodontic anchorage screw on the jawbone; the traction hook is connected to a lingual buckle or bracket pre-fixed to the surface of the tooth to be traction through an elastic traction section.
[0007] The connecting sleeve adopts a spring mechanism buckle, the inner diameter of which is 1.5-3.5 mm and slightly larger than the diameter of the circular cross-section of the neck of the orthodontic anchorage screw.
[0008] The extended traction chain has a smooth surface and a chain length of 10-30mm. The special chain length can be cut according to the individual differences of the patients to effectively transmit the appropriate amount of traction force.
[0009] The elastic traction section can be made of any one of the following: rubber chain, rubber ring, elastic wire, or nickel-titanium tension spring.
[0010] The original length of the elastic traction section Determined according to the following formula: In the formula, For the strain of the elastic traction section, This refers to the actual traction distance between the traction point on the tooth surface and the traction hook of the extended traction device.
[0011] A quantitative traction control method for an orthodontic anchorage screw-through mucosal lengthening device includes the following steps: Step (1) Measure the actual traction distance between the traction point on the tooth surface and the traction hook of the extension traction device. ; Step (2) Select the elastic traction segment used to connect the extension traction device to the traction point on the tooth surface, perform a uniaxial tensile test on the elastic traction segment, obtain the corresponding data of traction force and strain, and fit the corresponding data to establish a functional relationship model between traction force and strain: in, For traction force, For the strain of the elastic traction section, , , These are the fitting coefficients; Step (3) performs baseline correction on the functional relationship model to eliminate the influence of the initial baseline offset of the elastic traction section in the unstretched natural state, and obtains the corrected functional relationship model between traction force and strain; Step (4) Set the target traction force according to the clinical needs of orthodontics. and the target traction force Substituting the corrected functional relationship model obtained in step (3), the target strain required to achieve the target traction force is obtained by inverse calculation. ; Step (5) Based on the strain definition of the elastic traction section: in, The original length of the elastic traction segment in its unstressed natural state; the target strain obtained in step (4) and the actual traction distance measured in step (1) Substituting into the strain definition, the original length of the elastic traction segment that satisfies the target traction force requirement can be obtained by reverse calculation. ; Step (6) Based on the original length obtained in step (5) Select the appropriate elastic traction segment or cut the elastic traction segment to achieve quantitative control of orthodontic traction force.
[0012] The beneficial effects of this invention are: 1. This invention is movably connected to the orthodontic anchorage nail via a connecting sleeve. The connecting sleeve uses a spring mechanism buckle. The inner diameter of the elastic mechanism buckle is slightly larger than the diameter of the circular cross-section of the neck of the orthodontic anchorage nail. It is placed on the neck of the anchorage nail. While ensuring a firm connection, it can achieve force application in any direction and is not easy to fall off. It is very convenient to use and replace.
[0013] 2. When an anchorage screw is placed in an area easily embedded in the oral mucosa, the screw head often needs to be exposed again during follow-up visits for force adjustment, resulting in significant trauma and potentially causing pain and discomfort to the patient. This invention connects the anchorage screw to the anchorage screw via a connecting sleeve, allowing the extended traction chain to extend through the mucosa and be exposed in the oral cavity. The elastic force-adjusting attachment can be connected to the traction hook at the end of the extended traction chain or to the traction chain itself, eliminating the need to expose the anchorage screw head again. This effectively solves the problem of using or replacing the elastic force-adjusting attachment when the anchorage screw is embedded.
[0014] 3. The present invention extends the smooth surface of the traction chain, effectively avoiding the problems of traditional self-made ligature wires irritating the oral mucosa and easily fatigued and broken, reducing the incidence of traumatic oral ulcers and mucosal redness and inflammation during orthodontic treatment, improving patient comfort, and benefiting the health of the stomatognathic system and the improvement of orthodontic efficiency.
[0015] 4. This invention uses numerical simulation based on the mechanical performance test results of elastic force-applying attachments to achieve "digital" quantitative control and precise application of orthodontic traction force. In traditional clinical practice, doctors often rely on experience to count the degree of deformation and number of loops in the rubber band, making it difficult to accurately grasp the actual traction force generated. This invention transforms traditional "experience-based traction" into "quantitative traction" by performing systematic mechanical modeling of the chain-like rubber band and combining it with the actual clinical traction distance D for reverse compensation calculation. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the structure of an orthodontic anchorage nail-penetrating mucosal extension device according to the present invention.
[0017] Wherein: 1-connecting sleeve, 2-traction part, 21-extension traction chain, 22-traction hook, 3-orthodontic anchorage nail, 4-elastic traction section.
[0018] Figure 2 This is a schematic diagram illustrating the usage of an orthodontic anchorage nail-penetrating mucosal extension device in conjunction with a chain-like rubber band, according to the present invention.
[0019] Figure 3 This is a side view of the junction of the orthodontic anchorage screw mucosal extension device and the neck of the orthodontic anchorage screw according to the present invention.
[0020] Figures 4(a) to 4(d) are schematic diagrams of the uniaxial tensile test results of long-spacing and short-spacing chain rubber bands.
[0021] Figure 4(a) shows the traction force-displacement curve of the long-pitch chain rubber band under uniaxial tension; Figure 4(b) shows the traction force-strain curve of the long-pitch chain rubber band under uniaxial tension; Figure 4(c) shows the traction force-displacement curve of the short-pitch chain rubber band under uniaxial tension; and Figure 4(d) shows the traction force-strain curve of the short-pitch chain rubber band under uniaxial tension. Detailed Implementation
[0022] The technical solution of the present invention will now be clearly and completely described in conjunction with the accompanying drawings.
[0023] See Figures 1 to 3 An orthodontic anchorage screw mucosal extension device includes a connecting sleeve 1 and a traction part 2; the traction part 2 includes an extension traction chain 21 and a traction hook 22 connected to one end of the extension traction chain 21, the other end of the extension traction chain 21 is connected to one end of the connecting sleeve 1, and the other end of the connecting sleeve 1 is fitted onto the neck of the orthodontic anchorage screw 3 pre-fixed on the jawbone; the traction hook 22 or the extension traction chain 21 is connected to a lingual buckle or bracket pre-fixed on the surface of the tooth to be traction through an elastic traction section 4.
[0024] The connecting sleeve 1 uses a spring mechanism buckle. The inner diameter of the spring mechanism buckle is slightly larger than the diameter of the circular cross-section of the neck of the orthodontic anchorage nail 3, usually 1.5-3.5 mm.
[0025] The metal traction chain 21 has a smooth surface. Common chain length specifications are 10-30 mm, with a general chain length of 25 mm. Special chain lengths can be cut according to individual patient differences to effectively transmit appropriate traction force.
[0026] The elastic traction section 4 can be made of any one of the following: ligature wire, rubber chain, rubber ring, elastic wire or nickel-titanium tension spring.
[0027] A quantitative traction control method for an orthodontic anchorage screw-through mucosal lengthening device includes the following steps: Step (1) Measure the actual traction distance between the traction point on the tooth surface and the traction hook of the extension traction device. ; Step (2) Select the elastic traction segment used to connect the extension traction device to the traction point on the tooth surface, perform a uniaxial tensile test on the elastic traction segment, obtain the corresponding data of traction force and strain, and fit the corresponding data to establish a functional relationship model between traction force and strain: in, For traction force, For the strain of the elastic traction section, , , These are the fitting coefficients; Step (3) performs baseline correction on the functional relationship model to eliminate the influence of the initial baseline offset of the elastic traction section in the unstretched natural state, and obtains the corrected functional relationship model between traction force and strain; Step (4) Set the target traction force according to the clinical needs of orthodontics. and the target traction force Substituting the corrected functional relationship model obtained in step (3), the target strain required to achieve the target traction force is obtained by inverse calculation. ; Step (5) Based on the strain definition of the elastic traction section: in, The original length of the elastic traction segment in its unstressed natural state; the target strain obtained in step (4) and the actual traction distance measured in step (1) Substituting into the strain definition, the original length of the elastic traction segment that satisfies the target traction force requirement can be obtained by reverse calculation. ; Step (6) Based on the original length obtained in step (5) Select the appropriate elastic traction segment or cut the elastic traction segment to achieve quantitative control of orthodontic traction force.
[0028] Referring to Figure 4, based on the above-mentioned determination of the extended traction device structure, in order to further achieve precise control of the traction force, the present invention conducted a systematic mechanical performance test on the elastic traction section 4, which serves as the traction force source, and established a quantitative relationship between the traction force, the activation amount, and the length of the elastic traction section 4 based on the test results.
[0029] Determination of traction mechanical parameters and reverse calculation of the length of elastic traction section 4 (I) Mechanical testing and fitting analysis of long-distance elastic traction section 4 (corresponding to Figure 4(a) and Figure 4(b)) Referring to Figures 4(a) and 4(b), the traction force-displacement curve and traction force-strain curve of the long-distance elastic traction segment 4 under uniaxial tension conditions are shown, respectively. The test results show that within the effective working range of orthogonal traction, the traction force of the long-distance elastic traction segment 4 exhibits obvious nonlinear variation characteristics with the increase of displacement or strain.
[0030] Based on the experimental data, a quadratic polynomial model was used to perform nonlinear regression fitting for different samples. The fitting function is as follows: The curve comparison analysis results showed that there were statistically significant differences in the fitting curves between different samples. Therefore, individual fitting parameters were used to describe the mechanical behavior of each sample.
[0031] Among the multiple sets of samples, the sample with a higher goodness of fit has better model stability and can more accurately reflect the real mechanical response characteristics of the long-distance elastic traction section 4 in the conventional traction range. Therefore, it is selected as a representative embodiment in the preferred embodiment of the present invention for subsequent back-calculation of traction force parameters, and the remaining samples are used to verify the consistency and reliability of the model.
[0032] (II) Mechanical testing and fitting analysis of short-distance elastic traction segment 4 (corresponding to Figure 4(c) and Figure 4(d)) Referring to Figures 4(c) and 4(d), the traction force-displacement curves and traction force-strain curves of the short-span elastic traction segment 4 under uniaxial tension conditions are shown, respectively. Compared with the long-span elastic traction segment 4, the short-span elastic traction segment 4 exhibits a higher traction force growth rate under the same strain or displacement conditions, demonstrating greater equivalent stiffness characteristics.
[0033] Similarly, the test data of the four specimens with different short-distance elastic traction sections were fitted separately. The results showed that the traction force-displacement and traction force-strain relationships of each specimen could be described by a quadratic polynomial model, but there were some differences in the specific fitting parameters.
[0034] In a preferred embodiment of the present invention, a sample with a high goodness of fit and stable parameter changes is selected as a representative example of the short-distance elastic traction segment 4 for traction force back-calculation, and the remaining samples are used as auxiliary verification data.
[0035] (III) Division of labor and technical approach of force-displacement model and force-strain model In the mechanical analysis of the elastic traction segment 4, the traction force-displacement model can intuitively reflect the basic mechanical response characteristics of the elastic traction segment 4 during the tensile process, and is suitable for comparing and verifying the mechanical behavior of elastic traction segments 4 of different specifications. However, in actual orthodontic traction applications, due to differences in the initial working length, installation method, and pre-tension state of different elastic traction segments 4, simply extrapolating the traction force based on displacement is prone to errors. In contrast, the traction force-strain model normalizes the elastic traction segment 4 with its unpre-tensioned length as the benchmark, which can effectively eliminate the influence of initial length differences, making the resulting model more stable and universal.
[0036] Therefore, in this invention, the force-displacement model is mainly used to characterize the mechanical properties of the elastic traction segment 4, while the traction force back-calculation and clinical parameter calculation are preferably completed based on the force-strain model.
[0037] (iv) Method for determining the length of the elastic traction segment 4 based on the force-strain model and the reverse calculation of traction force In the clinical application of orthodontic traction, the magnitude of the traction force directly affects the efficiency of tooth movement and the safety of periodontal tissues. Based on orthodontic clinical experience, this embodiment selects 0.3~0.6 N as the preferred target traction force range for orthodontic traction.
[0038] Determine the actual traction distance between the traction point and the fixed point of the traction device. Subsequently, based on the traction force-strain fitting model of the representative elastic traction segment 4, the strain value required to achieve the target traction force is calculated in reverse. Furthermore, by combining the geometric relationship between strain and the initial length of the elastic traction segment 4, the length of the elastic traction segment 4 that meets the target traction force requirement can be derived, thereby achieving quantitative control of the traction force.
[0039] Fitting results of force-displacement curves for the long-distance elastic traction section (three samples): Under uniaxial tension conditions, the traction force of the long-distance elastic traction section 4 is... The relationship between the displacement Δ and the displacement can be described by a quadratic polynomial function: F(Δ) = B0 + B1 Δ+B2 Δ 2 in: The traction force (N) generated by the elastic traction section 4; The tensile displacement (mm) of the elastic traction section 4. , , represents the fitting coefficient.
[0040] Sample 1 Sample 2 Sample 3 Goodness of fit: 0.9845, 0.9830, 0.7923 This indicates good fit within the actual orthodontic traction working range. Define effective traction force: in The initial force of elastic traction segment 4 without effective traction can be approximated by the fitted intercept. The baseline-corrected back-inference model is as follows: Then let: We can then solve for Δ. 0.3 Δ 0.6 In this embodiment, a uniaxial tensile mechanical test was performed on the long-distance elastic traction section 4 to obtain its traction force-displacement curve. Experimental results show that within the effective traction range, the traction force and displacement exhibit a nonlinear relationship, which can be fitted using a quadratic polynomial model. By performing curve fitting on different samples, the force-displacement relationship function corresponding to each sample was obtained, and its coefficient of determination was determined. All values are greater than 0.79, indicating that the model can effectively describe the mechanical behavior of the long-distance elastic traction segment 4 during orthodontic traction. In practical applications, to eliminate the influence of the initial preload of the elastic traction segment 4 on the calculation of traction force, a baseline correction method is further introduced. The intercept term in the fitting function is used as the starting force in the state without effective traction, thereby establishing the correspondence between the effective traction force and the activation amount of the elastic traction segment 4, providing a quantitative basis for subsequently calculating the required stretching length of the elastic traction segment 4 based on the target traction force.
[0041] Fitting results of force-strain curves for the long-distance elastic traction section (three samples): Original fitted model (uncorrected): The force-strain relationship is modeled using a quadratic polynomial: Substitute the fitting parameters from Sample 1: get: in: : Traction force (N) Engineering strain (dimensionless) Baseline correction: To eliminate the influence of the initial preload of elastic traction section 4, the following is taken: Define effective traction force: The baseline-corrected relationship is then: Reverse calculation of the strain corresponding to the target traction force of 0.3-0.6 N. Solve the equation: Taking the smaller positive root that is physically valid, the calculation results are as follows: Target effective traction Required strain 0.3 N =0.081 0.6 N =0.163 The strain range is within the stable elastic working section of the long-distance elastic traction segment 4, which meets the safety requirements for orthodontic traction.
[0042] Based on the total traction distance D, the initial length L0 of the elastic traction section 4 is calculated. The geometric relationship between strain and length is as follows: Example calculation (D = 10 / 20 / 30 mm) (1) D = 10 mm (2) D = 20 mm (3) D = 30 mm In this embodiment, a uniaxial tensile test was conducted on the long-distance elastic traction segment 4 to obtain its traction force-strain relationship curve. Experimental results show that within the effective working range of orthodontic traction, the traction force exhibits a nonlinear variation characteristic with increasing strain, which can be fitted using a quadratic polynomial model, with a fitting determination coefficient R² exceeding 0.98. To eliminate the influence of the initial preload of the elastic traction segment 4 on the traction force calculation, the intercept term in the fitting function is used as the baseline force under no-effective traction conditions, and baseline correction is performed on the traction force, thereby establishing a quantitative relationship between the effective traction force and the strain of the elastic traction segment 4. Based on the established force-strain model, given the total distance between the traction point and the fixed point, the strain of the elastic traction segment 4 required to achieve the target traction force can be calculated in reverse. Furthermore, the initial length of the required elastic traction segment 4 can be deduced based on the correspondence between strain and length geometric parameters, achieving precise control of the traction force within the range of 0.3-0.6 N.
[0043] Fitting results of force-displacement curves for the short-distance elastic traction section (three samples): In this embodiment, a uniaxial tensile test was conducted on the short-distance elastic traction section 4, and the relationship between its traction force and displacement was recorded. The experimental data were fitted using a quadratic polynomial model for nonlinear regression, and the fitting function is as follows: in, The traction force (N) generated by the elastic traction section 4. The displacement is the tensile displacement (mm).
[0044] The curve comparison analysis results show that there are significant differences in the fitting curves between different samples (P < 0.0001). Therefore, the mechanical properties of each sample were described by individual fitting method, and the results are as follows.
[0045] (a) Force-displacement fitting formula for Sample 1 The fitting parameters are: The traction force-displacement relationship for Sample 1 is obtained as follows: The goodness of fit of the curve is This indicates that the model can well reflect the mechanical response characteristics of the short-distance elastic traction segment 4 under the sample conditions.
[0046] (ii) Force-displacement fitting formula for Sample 2 The fitting parameters are: The corresponding traction force-displacement relationship is: The goodness of fit of this sample is The results show that within a large displacement range, the traction force exhibits an accelerating growth trend with displacement.
[0047] (III) Force-displacement fitting formula for Sample 3 The fitting parameters are: The corresponding traction force-displacement relationship is: Its goodness of fit is This reflects that the force of the sample increases rapidly in the small displacement stage, while it exhibits a certain nonlinear gradual increase characteristic in the larger displacement range.
[0048] The results above show that the traction force-displacement relationship of the short-distance elastic traction segment 4 can be described by a quadratic polynomial model under different sample conditions. Although the specific parameters of each sample are somewhat different, they all show a nonlinear variation law in which the traction force gradually increases with the increase of displacement, providing a mechanical basis for subsequently inferring the activation amount and working length of the elastic traction segment 4 based on the target traction force.
[0049] Fitting results of force-strain curves for the short-distance elastic traction section (three samples) In this embodiment, a uniaxial tensile test was conducted on the short-distance elastic traction segment 4 to obtain its traction force-strain relationship curve. The experimental data were analyzed using a quadratic polynomial model for nonlinear regression, and the fitting function is as follows: in, The traction force (N) generated by the elastic traction section 4. For engineering strain (dimensionless).
[0050] The fitting results are as follows.
[0051] (a) Force-variable fitting formula for Sample 1 The fitting parameters are: The traction force-strain relationship for Sample 1 is obtained as follows: Its goodness of fit is This indicates that the model can well describe the mechanical response characteristics of Sample 1 within the orthodontic traction working range.
[0052] (ii) Force-strain fitting formula for Sample 2 The fitting parameters are: The corresponding traction force-strain relationship is: Its goodness of fit is This indicates that the traction force of the specimen increases more significantly within a larger strain range.
[0053] (III) Force-strain fitting formula for Sample 3 The fitting parameters are: The corresponding traction force-strain relationship is: Its goodness of fit is This reflects that the sample exhibits a higher rate of traction force growth and a more significant degree of nonlinearity within a higher strain range.
[0054] Baseline correction (eliminating initial preload) To eliminate the influence of the initial pretension of elastic traction segment 4 on the calculation of clinical traction force, the following definition is used: The effective traction force-strain relationship after baseline correction is: Based on the total traction distance D, the initial length of the elastic traction segment 4 can be calculated. The geometric relationship between strain and length is as follows: in, The force-strain fitting curve of the short-range elastic traction segment (Sample 1) is used to determine the effective traction force at the target. and The strain obtained by reverse calculation.
[0055] The reverse thrust strain of short-pitch elastic traction segment 4 (Sample 1) is: Target effective traction Required strain 0.3 N =0.082 0.6 N =0.165 The strain range is within the stable elastic working section of the short-distance elastic traction segment 4, which meets the safety requirements for orthodontic traction.
[0056] Based on the total traction distance D, the initial length L0 of the elastic traction section 4 is calculated. The geometric relationship between strain and length is as follows: Example calculation (D = 10 / 20 / 30 mm) (1) D = 10 mm (2) D = 20 mm (3) D = 30 mm As can be seen from the above fitting results, although there are certain differences in specific parameters among the different short-distance elastic traction segment 4 specimens, their traction force-strain relationship can be effectively described by a quadratic polynomial model, and they exhibit a consistent nonlinear variation law within the effective working range of orthodontic traction. In practical applications, representative curves can be selected based on the goodness of fit for quantitative back-calculation of traction force parameters, while the remaining specimens are used to verify the stability and consistency of the model. Through the above method, this invention can, under the premise of knowing the traction path and traction distance, determine the length specification of the elastic traction segment 4 in reverse based on the mechanical model obtained from experimental fitting, so that the traction force is stably controlled within the target range. This method avoids the uncertainty caused by the traditional reliance on experience to select the traction force source, improves the safety, controllability, and repeatability of the orthodontic traction process, and provides a reliable solution for personalized orthodontic traction.
[0057] This invention is movably connected to the orthodontic anchorage screw via a connecting sleeve 1 (elastic mechanism buckle). Since the inner diameter matches the minimum diameter of the circular cross-section of the neck of the orthodontic anchorage screw 3, force can be applied in any direction by connecting the elastic traction device (such as the elastic traction segment 4) to the lingual buckle or bracket on the tooth surface while ensuring a firm connection. The required length of the elastic traction segment 4 can be determined based on the mechanical test results of the elastic traction segment 4 and the actual clinical traction distance, so that the traction force can be applied in a controllable and precise manner. It is very convenient to use, and the elastic traction device can be replaced quickly. It also effectively avoids the stimulation of the oral mucosa caused by the traditional use of ligature wire, reduces the incidence of traumatic oral ulcers during orthodontics, and improves the patient's comfort.
Claims
1. An orthodontic anchorage stapled mucosal extension device, comprising a connecting sleeve (1) and a traction part (2); characterized in that, The traction unit (2) includes an extension traction chain (21) and a traction hook (22) connected to one end of the extension traction chain (21). The other end of the extension traction chain (21) is connected to a connecting sleeve (1). The connecting sleeve (1) is fitted onto the neck of the orthodontic anchorage screw (3) that is pre-fixed on the jawbone. The traction hook (22) is connected to the lingual buckle or bracket that is pre-fixed to the surface of the tooth to be traction through an elastic traction section (4).
2. The orthodontic anchorage stapled mucosal extension device according to claim 1, characterized in that: The connecting sleeve (1) adopts a spring mechanism buckle, the inner diameter of which is 1.5-3.5 mm and larger than the diameter of the circular cross section of the neck of the orthodontic anchorage nail (3).
3. The orthodontic anchorage stapled mucosal extension device according to claim 1, characterized in that: The extended traction chain (21) has a smooth surface and a chain length of 10-30mm. The special chain length can be cut according to the individual differences of the patients.
4. The orthodontic anchorage stapled mucosal extension device according to claim 1, characterized in that: The elastic traction section (4) is made of any one of rubber chain, rubber ring, elastic wire or nickel-titanium tension spring.
5. The orthodontic anchorage stapled mucosal extension device mucosa according to claim 1, characterized in that: The original length of the elastic traction section (4) Determined according to the following formula: In the formula, For the strain of the elastic traction section (4), The actual traction distance between the traction point on the tooth surface and the traction hook (22) of the extended traction device.
6. A quantitative traction control method for an orthodontic anchorage stapled mucosal lengthening device, characterized in that, Includes the following steps: Step (1) Measure the actual traction distance between the traction point on the tooth surface and the traction hook (22) of the extension traction device. ; Step (2) Select the elastic traction segment (4) used to connect the extension traction device to the traction point on the tooth surface, perform a uniaxial tensile test on the elastic traction segment (4), obtain the corresponding data of traction force and strain, and fit the corresponding data to establish a functional relationship model between traction force and strain: in, For traction force, For the strain of the elastic traction section (4), , , These are the fitting coefficients; Step (3) performs baseline correction on the functional relationship model to eliminate the influence of the initial baseline offset of the elastic traction segment (4) in its unstretched natural state, and obtains the corrected functional relationship model between traction force and strain; Step (4) Set the target traction force according to the clinical needs of orthodontics. and the target traction force Substituting the corrected functional relationship model obtained in step (3), the target strain required to achieve the target traction force is obtained by inverse calculation. ; Step (5) is based on the strain definition of the elastic traction segment (4): in, The original length of the elastic traction segment (4) in its unstressed natural state; the target strain obtained in step (4) and the actual traction distance measured in step (1) Substituting into the strain definition, the original length of the elastic traction segment (4) that satisfies the target traction force requirement is obtained by reverse calculation. ; Step (6) Based on the original length obtained in step (5) Select the corresponding specification of the elastic traction segment (4), or cut the elastic traction segment (4) to achieve quantitative control of orthodontic traction force.