A radius determination method based on the density of orthodontic archwire bending points

Abstract

The invention discloses a method for determining the radius of a plane equal-radius circle domain division based on the density of orthodontic arch wire bending points, which relates to the technical field of orthodontic arch wire bending. Based on the orthodontic archwire curve bending point information set and the robot bending information set of the bending point, combined with the motion characteristics of the robot bending orthodontic archwire, a planar equal radius based on the orthodontic archwire bending point density is established The method for determining the radius of the circle domain division. The technical points are: equal radius to determine the circle domain division data import and orthodontic archwire curve conversion; calculate the equal radius to determine the initial trial division number of the circle domain; try to divide the equal radius to determine the circle domain; find the best trial division number; the output is reasonable Density equal-radius circle domain division radius r equal . The present invention adopts density judgment to adjust the number of trial-divided circles, determines the division radius value of equal-radius circles with reasonable density, improves the efficiency of equal-radius circle division, further improves the efficiency of orthodontic arch wire bending planning, and avoids robot bending. The problem of interference in the process of making orthodontic archwires.

Description

technical field [0001] The patent of the invention relates to a method for determining the radius of a plane equal-radius circular domain division based on the density of orthodontic archwire bending points, and belongs to the technical field of orthodontic archwire bending. Background technique [0002] Malocclusion is the third largest oral disease that endangers human health, showing a high incidence rate. In modern stomatology, fixed orthodontics is a commonly used and effective orthodontic treatment, and the bending of orthodontic archwires is a fixed In recent years, the key to orthodontic technology has been deeply influenced by digital manufacturing technology. The traditional oral manufacturing process is undergoing revolutionary changes. The field of orthodontics is also benefiting from digital technology. The processing of arch wires in orthodontic appliances is becoming digital. develop. [0003] In the process of bending the personalized orthodontic archwire by...

AI Technical Summary

Problems solved by technology

[0003] In the process of bending the personalized orthodontic archwire by the robot, there may be interference between the personalized orthodontic archwire and the robot's bending claw. Afterwards, it will greatly affect the bending accuracy of the personalized orthodontic arch wire, and then affect the correction effect, so that the bent personalized orthodontic arch wire cannot be applied to clinical treatment; In the process of wire bending, the forward bending means that the unbent orthodontic arch wire is bent into a complex shaped arch wire. The interference is often caused by the unreasonable bending sequence of the forming control points, while the reasonable forward bending The bending sequence of forming control points can effectively avoid the occurrence of interference, and obtaining a reasonable bending sequence of forming control points in forward bending is a necessary prerequisite for realizing digital bending of orthodontic archwires. However, the current orthodontic archwire bending technology The field lacks a method for planning the bending sequence of the control points of the forward bending, and it is difficult to realize the digital bending of orthodontic archwires

[0004] For the research on the division field of orthodontic arch wire bending planning, it is proposed in the invention patent "A Method for Dividing Circles for Orthodontic Arch Wire Bending Planning" with the authorized announcement number CN107647925B that the inventor has authorized A method of equal-radius circle domain division, which divides the area on the orthodontic archwire curve, and finally sorts each area, so as to obtain the bending order of the final bending point, although this method has no effect on the orthodontic archwire curve. However, because this method only divides the orthodontic archwire curve with an unfounded uniform standard, there are usually too many bending points and bending points in the divided circular area. The situation where the complexity is too large, that is, the divided interval does not fully consider the individual characteristics of the distribution information of the bending points on the orthodontic archwire curve. For example, the bending points on the patient's personalized orthodontic archwire often have overall bending In the case where the difficulty of point bending is relatively small, a bending point angle-to-distance ratio E can usually be used to measure the difficulty of bending a single bending point on the orthodontic archwire curve j To verify, the expression is where α j is acting on the bending point t j The bending angle at , t j-1 t j means acting on the bending point t j The value range of j is 11 The angle-to-distance ratio of the bending point is E 1 =0, if the maximum value of the angle-to-distance ratio of all bending points on the orthodontic archwire curve can be known by calculation Not greater than the specified upper limit E of the angle-to-distance ratio of the bending point max , it can be seen that on the selected personalized orthodontic archwire curve, no matter whether the divided circular domain contains any number of bending points that meet the limit of the number of bending points, the divided circular domain can still guarantee the circular domain bending The difficulty of bending in the circular domain of the point is within the acceptable range, which can meet the requirements of the bending system for the difficulty of bending. The influence of the angle-to-distance ratio factor of the archwire, that is, the distribution of the bending point of the archwire has special properties. The rationality of the planning method is poor, and it is impossible to realize efficient digital bending of this kind of personalized orthodontic archwire, so that it is impossible to effectively avoid the invalid motion of the bending robot due to the unreasonable planning of the bending sequence, the mutual interference of the bending process, and the The complex movements of the bending movement are not conducive to maximizing the advantages of the bending robot, nor can it significantly improve the bending efficiency

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