Three-dimensional Image Processing Of The Efficiency Of The Overcorrection Twisted Canines With Removable Clear Appliance

Background and PurposeBecause of the elasticity,transparence and detachability of the materials,removable clear aligner has the advantages of beauty,comfort and convenience,which has become the first choice for more and more orthodontic patients with greater aesthetic requirements.With the development of materials and the progress of technology,the effect of removable clear aligner has been continuously improved,but because of the characteristics of the materials,the short board of the removable clear aligner still exists.In order to achieve the goal of treatment,clinicians need to have rich experience of removable clear aligner.For the tooth movement with low efficiency,we need to cooperate with the orthodontic design to improve the tooth movement efficiency,reduce the number of midcourse correction and shorten the orthodontic time.However,there are few reports about the appropriate overcorrection degree and the efficiency of tooth movement.This experiment will design the overcorrection of teeth with different rotation degrees,find the best overcorrection degree for teeth with different rotation angles,improve the efficiency of teeth,reduce the midcourse correction times,and avoid the reciprocating movement of teeth.MethodsTwenty-four patients who met the inclusion criteria were randomly selected and divided into two groups according to the degree of torsion of upper occlusal canines.The overcorrection design of two groups of teeth with different degrees of rotation was carried out,and the digital model of intraoral scanning before and after one-stage treatment was collected.Finally,spss19.0 software package was used to analyze the experimental data.ResultsThere was significant difference between the actual rotation degree of upper occlusal canine and the preset value of Clincheck Pro(P = 0.000).The higher the rotation angle of upper occlusal canines,the lower the efficiency of overcorrection.The efficiency of overcorrection was 60.81% for the upper occlusal canines with 0 °~15 ° torsion,and 56.13% for theupper occlusal canines with 15°~ 30° torsion,There was a statistical difference in the rotation angle between the two groups(P = 0.000).The degree of upper occlusal canines torsion had little effect on the efficiency of 3° overcorrection(P = 0.012),but had great effect on the efficiency of 5 ° overcorrection(P = 0.001).Regardless of the degree of torsion,the rotation efficiency of 5 ° overcorrection design was higher than that of 3 ° overcorrection design(P = 0.000,P = 0.026).Conclusions1.In the process of removable clear aligner,overcorrected design can improve the rotation efficiency of upper occlusal canine.2.The orthodontic efficiency of removable clear aligner is related to the torsion angle of upper occlusal canine.With the increase of torsion angle,the rotation efficiency of teeth is reduced.3.Overcorrection design can improve the efficiency of twisted upper occlusal canine by the removable clear aligner,and 5 ° overcorrection design can improve the tooth movement design better than 3 ° overcorrection design.