The present prospective clinical study was directed to evaluate the efficiency of three different aligning archwires during initial orthodontic leveling.

The present prospective clinical study was directed to evaluate efficiency of three different aligning arch wires during initial orthodontic leveling.

The sample of present study included 30 patients, 15 females and 15 males; with a mean age was 17.81 ± 1.96 years. They were randomly allocated into three equal groups, according to the type of the aligning arch wire as follows:

1. Group A: in which 10 patients, with a mean age was 17.27 ± 1.95 years, were treated with conventional singlestrand NiTi arch wires.
2. Group B: in which 10 patients, with a mean age was 17.33 ± 2.42 years, were treated with Niobium-titanium-tantalum-Zirconium (Gummetal) arch wires.
3. Group C: in which 10 patients, with a mean age was 18.70 ± 1.49 years, were treated with multistrand NiTi arch wires.

Mandibular orthodontic study models were taken every 4 weeks and laser scanned to obtain 3D digital models during the 3 months observation period of the study. The changes in LII were determined at every 4 weeks observation intervals. Moreover, the changes in inter-canine, inter-1st premolar and inter-molar widths before and after three months were evaluated and compared among the three groups of aligning arch wires.

Data were collected and statistically analyzed via Statistical Package for Social Science (SPSS, version 23). One Way ANOVA and Kruskall-Wallis tests were used to assess the difference among the three studied groups and paired t-test was used to assess the difference and percent of changes within each group before and after three months observation period.

Inclusion criteria:

• An age range from 15 to 20 years
• All permanent teeth have erupted (3rd molar not included)
• Angle class I malocclusion with normal facial proportions.
• Moderate crowding in the lower dental arch that required treatment with fixed appliance using the non-extraction approach.
• Good oral hygiene with healthy periodontium, good general health without any systematic disease that could affect the treatment.

Exclusion Criteria:

• Severe crowding that requires an extraction approach.
• A blocked-out tooth that prevent the easy placement of the bracket at the initial bonding appointment.
• Poor oral hygiene or periodontal compromised teeth.
• Relevant medical history and/or regular medication that contraindicates and/or interferes with orthodontic treatment.
• Craniofacial anomalies or previous history of trauma, bruxism, or parafunction.
• Previous orthodontic treatment.