A three-dimensional comparison of torque achieved with a preadjusted edgewise appliance using a Roth or MBT prescription.

Objective: To investigate if there are any significant differences in the final inclination of the upper and lower anterior teeth of patients treated with a Roth or an MBT bracket prescription. Materials and Methods: Forty sets of posttreatment study models from patients treated using a preadjusted edgewise appliance (20 Roth and 20 MBT) were selected using predetermined inclusion and exclusion criteria. The models were masked and laser-scanned, and the final crown inclinations of UL1, UR3, and LR1 were assessed from the digital images. A two-way analysis of variance was undertaken with the dependent variable of final crown inclination and independent variables of bracket prescription (Roth or MBT) and tooth type. Results: There were no statistically significant differences in terms of the final inclination of the anterior teeth between the two bracket prescriptions (P  =  .132). Statistically significant differences were found between the final inclinations of different tooth types investigated (P < .001). Conclusion: In this group of selected patient records, the differences in torque values between the two bracket prescriptions did not lead to any real clinically detectable differences in the final inclination of teeth.