Comparison of Bracket Bonding Between Two CAD/CAM Guided Bonding Devices: GBD-U Vs GBD-B.

Objective: To compare the bracket bonding accuracy, efficiency, reproducibility, and three-dimensional (3D) printing duration of the computer-aided design/computer-aided manufacturing (CAD/CAM) unilateral contact guided bonding device (GBD-U) and the bilateral contact guided bonding device (GBD-B) in vitro. Methods: Five resin dental model sets were scanned and virtually bonded with brackets. GBD-U and GBD-B were designed and 3D printed for each model. GBD-Us had guide blocks that fit the occlusal sides of the bracket tiewings, while GBD-Bs had guide arms that fit the occlusal and distal sides of the tie-wings. Five orthodontic residents were recruited to bond brackets on the same 3D-printed copies of resin models in a dental mannequin using GBD-Us and GBD-Bs, respectively. The time for 3D printing of GBDs and bracket bonding was recorded. The linear and angular deviations between the bonded brackets and the virtually bonded ones were measured. Results: A total of 50 sets of resin models (1000 brackets/tubes) were bonded. The time for 3D printing and bracket bonding was shorter for GBD-Us (41.96 mins/6.38 mins) than for GBD-Bs (78.04 mins/7.20 mins). In both devices, 100% linear deviations and over 95% angular deviations were below 0.5 mm or 2 degrees, respectively. Deviations in the mesiodistal dimension, torque, angulation, and rotation were significantly lower in the GBD-U group (P<0.01). High inter-operator reproducibility of bracket bonding was confirmed for both devices. Conclusion: GBD-U was more time-efficient in 3D printing. Both GBDs showed clinically acceptable accuracy, whereas GBD-U had higher bonding accuracy in the mesiodistal dimension, torque, angulation, and rotation than GBD-B.