Three Dimensional Finite Element Analysis Of Torque Control Of Anterior Teeth With Edgewise Appliance And Ribbon Arch Appliance

Objective:Compare the torque control effect of edgewise arch wire and ribbon arch wire by three-dimensional finite element method.Methods:Using computer software and three-dimensional finite element analysis method,we constructed the maxillary and mandibular dentition,jaw and periodontal ligament,and designed horizontal groove 0.022 × 0.028 inch bracket and vertical groove 0.028× 0.022 inch bracket on the labial side of upper and lower central incisors and lateral incisors,and used 0.017 × 0.025 inch and 0.019 × 0.025 inch edgewise brackets in horizontal groove respectively 025 × 0.017 inch and 0.025 × 0.019 inch ribbon archwires were used in the vertical groove.According to this,four working conditions(i.e.combination)were established:a new three-dimensional model of bracket and arch wire combined with three-dimensional model of maxillary and mandibular dentition.The torque was loaded on the corresponding working conditions,and the performance of edgewise arch wire and ribbon arch wire in controlling the torque of anterior teeth was compared,and the corresponding three-dimensional finite element analysis was made.Results:When the width and spacing of brackets are constant,in the three-dimensional finite element analysis experiment,the larger the arch wire,the greater the torque of the anterior teeth in the edgewise arch wire group,and the same in the ribbon wire group.The force nephogram showed that the torque of the ribbon arch group was greater than that of the edgewise arch wire group,and the torque value of each tooth in the ribbon arch group was greater than that of the edgewise arch wire group after eight upper and lower anterior teeth were loaded with torque,in the edgewise arch wire group,the upper incisors were 4.33,7.70,11.94 and 11.12,the upper central incisors were 1.65,2.50,1.97 and 3.19,the lower incisors were 8.97,8.69,12.33 and12.47,the lower central incisors were 0.95,1.07,1.30 and 1.57,the upper central incisors in the ribbon arch wire group were 15.84,18.93,16.72 and 20.54,and the upper central incisors in the ribbon arch wire group were 15.84,18.93,16.72 and20.54,respectively The incisors were 3.58,4.16,3.95 and 4.77,the lower incisors were 12.26,11.04,15.78 and 13.22,and the lower central incisors were 1.40,1.73,2.99 and 3.05,respectively.Torque value of the ribbon arch wire group was larger than the edgewise arch wire group,P < 0.05,with statistical significance;there are differences in torque control between the edgewise appliance and ribbon arch appliance.Conclusion:When the bracket width and bracket spacing are constant,the torque value of the ribbon appliance on the upper and lower anterior teeth is bigger than that of the edgewise appliance.