Introduction In adult Class II Division 1 cases treated by orthodontic camouflage, the extraction of the maxillary first premolars is commonly followed by retraction of the anterior segment. Achieving this movement efficiently while maintaining adequate torque control remains a major clinical concern. Materials and methods This preliminary clinical report evaluated the performance of a bidimensional bracket system combined with miniscrew-supported anchorage in seven adult patients treated with the extraction of the maxillary first premolars followed by en masse retraction of the upper anterior segment. After completion of leveling and alignment, retraction was initiated using nickel-titanium closed-coil springs delivering 250 g of force per side. The assessed outcomes were the change in maxillary incisor torque on cephalometric images, measured using the bracket-archwire angle, and the rate of anterior retraction on 3D digital models, measured as the distance from the incisal edge of the maxillary central incisors to the medial endpoint of the third right palatal rugae. The statistical analysis was exploratory, and 95% CIs were calculated for the main clinical estimates. Results Repeated measurements demonstrated high reliability, with intraclass correlation coefficients ranging from 0.971 to 1 and no statistically significant systematic error. The mean change in maxillary incisor torque following retraction was 1.54 ± 0.27° (95% CI: 1.29-1.79°). The monthly retraction rate ranged from 0.67 ± 0.05 to 0.75 ± 0.08 mm/month, with an overall mean of 0.71 ± 0.04 mm/month (95% CI: 0.67-0.75). Total retraction reached 5.60 ± 0.72 mm, corresponding to 88.32% of the extraction space, and the mean duration required to complete en masse retraction was 7.89 ± 1.11 months. No patient withdrawal, miniscrew failure, peri-miniscrew inflammation requiring screw removal, or appliance-related complication interrupting treatment was recorded. Conclusions Within the limitations of this exploratory preliminary report, the bidimensional bracket system used with miniscrew-supported anchorage appeared to preserve torque well, along with a controlled and clinically acceptable rate of anterior retraction. This approach may represent a useful biomechanical option for improving 3D control during space closure.
Almasri et al. (Wed,) studied this question.