Materials & Methods: 40 patients with mandibular incisal crowding were selected. Two groups were formed of both gender. First group (Group I) patients were treated with nickel- titanium arch wires and second group (group II) patients with clear aligners. Crowding was assessed using little’s irregularity index. The linear horizontal displacement of the anatomic contact points of mandibular anterior teeth was measured and added which denoted total irregularity score. Patients were recalled regularly at 4 weeks, 8 weeks and 12 weeks.

Results: At baseline, mean score in first group was 2.94 mm and in second was 2.70 mm, at 4 weeks in first group was 1.68 mm and in second group was 1.50 mm, at 8 weeks in first group was 0.94 mm and in second group was 1.4 mm and at 12 weeks in first group was 0.64 mm and in second group was 0.56 mm. The difference was non- significant (P> 0.05). The mean change in little’s irregularity index score at 4 weeks in first group was 1.28 mm and in second group was 1.21 mm, at 8 weeks was 0.75 mm in first group and 0.46 mm in second group and at 12 weeks was 0.37 mm in first group and 0.74 mm in second group. The difference was significant (P< 0.05).

Conclusion: Both nickel titanium wires and clear aligners were equally efficient in managing mandibular anterior crowding