Comparison of torque control between two commonly used 0.018-inch pre-adjusted edgewise bracket systems in North Indian population: a retrospective study

Abstract

ABSTRACT Objective To compare the torque control between 0.018-inch MBT and Roth Pre-adjusted edgewise appliance in Angle’s Class I malocclusion patients treated with all first premolar extraction. Materials and Methods 40 patients with Angle’s Class I malocclusion treated with fixed orthodontic appliances using MBT (Group I) and Roth (Group II) prescriptions and extraction of all first premolars were included in the study. All the patients had tooth material-arch length discrepancy of >10 mm. Pre- (T1) and post-treatment (T2) study models were evaluated for the expression of torque (labio-lingual inclination). Torque was measured on study models using a Torque angulation device. Paired t-test and unpaired t-test were used for intra-group and inter-group comparison, respectively. P < 0.05 was considered to be statistically significant. Results In Groups I and II, the pre- to post-treatment differences in labio-lingual inclination decreased significantly (P < 0.05) for following teeth: 11, 21, 12, 22, 13, 23, 31, 41, 32 and 42. Intergroup comparison of Group I and Group II showed statistically significant difference (P < 0.05) in the mean change of labio-lingual inclination of following teeth: 11, 21, 12, 22, 16, 26, 31, 41, 32, 42, 33, 43, 36 and 46 teeth. Group I shows higher torque expression when compared to Group II. Conclusion The final position of maxillary and mandibular anterior teeth showed better torque expression by MBT compared to the Roth pre-adjusted edgewise appliances. Inadequate torque control was observed in mandibular posterior teeth treated by Roth prescription appliances.