Patient-Reported Pain During Initial Leveling with Three Types of Nickel–Titanium Orthodontic Archwires: A Single-Blinded Comparative Study

Background: Patient discomfort during the initial phase of orthodontic treatment is a common concern and may influence compliance. Archwire selection plays a critical role in modulating pain perception. This study aimed to compare immediate and dynamic pain perception among patients undergoing initial orthodontic leveling using three types of nickel–titanium archwires with different mechanical properties and cross-sectional dimensions. Methods: Forty-eight patients undergoing fixed appliance therapy were enrolled in a single-blind comparative clinical study. Participants completed a two-part, pilot-tested questionnaire assessing immediate (Day 4) and dynamic (Day 8) pain after the first archwire placement. Group differences were analyzed with Kruskal–Wallis and Bonferroni-adjusted Mann–Whitney U tests (α = 0.05). Results: TriTanium® was consistently associated with lower pain across functional tasks and had significantly lower overall pain than both Bio-Active® and 0.014-inch single-force round Ni-Ti (Bonferroni-adjusted). Bio-Active® was intermediate and did not differ from 0.014-inch round; its reduction relative to the round wire showed a non-significant trend. No correlation was found between archwire size and pain intensity. Conclusions: The type and mechanical behavior of the archwire, rather than its cross-sectional dimension, influence patient discomfort during the initial leveling phase. Multiforce shape-memory archwires such as TriTanium® may offer improved comfort and should be considered when planning early-stage orthodontic treatment.