Effects of Self-ligating Orthodontic Appliances on the Periodontal Health of Adolescents: A Prospective Cohort Study

Purpose: To evaluate the association between orthodontic treatment with fixed appliances and periodontal health during treatment by examining gingival inflammation indices and saliva properties. Materials and Methods: Thirty consecutive orthodontic patients, aged 11-18 years old, who were eligible for fixed orthodontic appliances, were included in the study. Plaque index (PI), gingival index (GI), salivary pH and flow rate were recorded at three timepoints: immediately before placement of orthodontic fixed appliances (T-0), and 1 (T-1) and 3 months (T-2) after bonding. Results: The hypothesis that PI would remain constant across timepoints was rejected. PI increased over time (0 to 1 scale, T-1-T-0: mean diff. = 0.10, 95% CI = 0.03, 0.18, p = 0.01; T-2-T-0: mean diff. = 0.16, 95% CI = 0.08, 0.24, p < 0.001). On the other hand, GI changed statistically significantly over time (p = 0.05). Patients' age was not a predictor for PI change (p = 0.93), but it was for GI (p = 0.01). As anticipated, average PI was found to be higher for the mandibular dentition by 0.10 (95% CI = 0.04, 0.16) and the labial surfaces of teeth of both jaws by 0.51 (95% CI = 0.45, 0.57). Conclusions: Within the framework of the current study, orthodontic treatment appeared to affect the periodontal health of patients, but the changes were clinically negligible and not consistently statistically significant.