Comparison of pain perception caused by aligner and conventional fixed orthodontic treatments

The aim of this study was to compare the pain perceived in fixed orthodontic and aligner treatments during the first seven days of treatment. Forty patients who had 3–6 mm maxillary dental crowding and a non-extraction treatment plan were included in this study. The subjects were randomly divided into two groups: the fixed orthodontic group and the aligner group, with ten females and ten males in each. In the fixed orthodontic group, treatment was started with 0.014-inch round nickel-titanium archwire, and a 0.018×0.025-inch preadjusted edgewise appliance was used. In the aligner group, treatment was started with a polyurethane aligner. Throughout the study, teeth in the upper jaw were treated in both groups. The pain scores of the subjects were measured with the visual analog scale at the second and sixth hours and on the first, second, third, and seventh days of treatment. The pain scores of the fixed orthodontic group were significantly higher than those of the aligner group at the sixth hour, on the first, second, and third day. The differences at the second hour and on the seventh day were not statistically significant. According to the study outcomes, less pain was felt during the aligner treatment compared to the fixed orthodontic treatment. However, it should be considered that the force activation interval is shorter in the aligner treatment, and the cumulative pain score may be higher.