Accuracy of a lingual indirect bonding system using a 3D virtual program

Abstract

Recently, 3D virtual setup program, a highly advanced computer-driven system has been used in indirect bonding, enabling customized patient treatment. It can decrease the number of steps in the existing manual setup used for indirect bonding, saving laboratory time. In addition, individual jigs for indirect bonding can be manufactured by the 3D virtual program based on the virtual setup model. However, it is unclear if this new system is more accurate than conventional methods because only a few studies have evaluated the accuracy of such cutting-edge bracket bonding techniques. We aimed to evaluate the accuracy of bracket placement for lingual indirect bonding techniques when a 3D virtual setup system (3TxerTM; Orapix, Seoul, Korea) is used in vitro. Four variables—torque, depth, tip, and height—were measured in order to evaluate the difference between virtual and actual bracket positions. A 3D program (Rapidform 2006TM; Inus Technology, Seoul, Korea) via a superimposition process was used for this purpose. The results of this study were as follows.1. All variables showed significant differences between the virtual and actual bracket positions (P < 0.001).2. The mean values of the absolute torque, depth, tip, and height error were 4.84° ± 3.33°, 0.33 mm ± 0.22 mm, 1.39° ± 1.05°, and 0.35 mm ± 0.27 mm, respectively.3. For all variables, the difference between the right and left and the maxilla and mandible was not significant.4. There was significant difference in torque between the 2-piece jig group (incisors, canines, and second premolars) and 1-piece jig group (first and second molars) (P < 0.001). Errors might occur during fabrication of the customized resin base or silicone transfer trays because these processes are executed manually. Therefore, control of manual laboratory procedures is a key factor for successful virtual indirect bonding along with the accuracy of digitations of plaster models. Clinically, in the final stage of treatment, wire bending, re-setup of the models, or re-bonding of the brackets may be required. Further studies are needed to improve the virtual indirect bonding system discussed in this study.