The Duration of Fixed Orthodontic Treatment: a Comparison of Two Groups of Patients Treated Using Edgewise Brackets with 0.018" and 0.022" Slots

The duration of fixed appliance Edgewise orthodontic treatment times using brackets with 0.018" and 0.022" slots was measured to determine whether there were any clinically or statistically significant differences between the two appliances. Sixty-four consecutively treated, fully banded patients were selected from two different practice locations. All 64 patients were treated by one clinician. Thirty-two patients (Group 1) were treated using the 0.018" slot bracket and 32 (Group 2) were treated using the 0.022" slot bracket. The patients in each group were treated to the same standard of care using the same technique. The mean duration of treatment for Group 1 was 20.2 months and for Group 2, 21.7 months. Although the mean difference (1.5 months) was not clinically significant, it was statistically significant at p < 0.05.