The effectiveness of clear aligner therapy has not been fully studied so far. The present study aimed to investigate the quality of life in patients undergoing fixed orthodontic treatment and clear aligner therapy regarding anxiety levels, patient satisfaction, and oral health outcomes. In this descriptive-analytical study, 200 patients were studied, 100 of whom underwent clear aligner therapy and 100 of whom underwent fixed orthodontic treatment. The effects of these two treatments on the oral health quality of these patients' lives were compared using the Oral Health Impact Profile (OHIP-14) questionnaire. Additionally, patient satisfaction was assessed using the Patient Satisfaction Questionnaire (PSQ-18). In addition, patients' anxiety was assessed using the State-Trait Anxiety Inventory. In this study, 122 female and 78 male patients participated. The mean quality of life of a healthy mouth was 53.26, the mean patient satisfaction was 42.46, and the average treatment-related anxiety was approximately 72.26. The findings showed that the clear aligner treatment group experienced significantly more anxiety on average than the fixed orthodontic treatment group (P < 0.001). Compared to the fixed orthodontic treatment group, the mean quality of life of the clear aligner treatment group in terms of oral health was significantly lower (P < 0.001). The findings of the present study showed that beneficiaries of clear aligner treatment had a lower quality of life and higher levels of worry and contentment.
