Clinical evaluation of the effect of clear aligners on periodontal health

While orthodontic treatment provides significant functional and aesthetic benefits, its impact on periodontal health remains a relevant topic of investigation. Particularly regarding plaque accumulation and its effects on soft tissues, understanding the periodontal implications of clear aligner therapy (CAT)—an aesthetic and removable alternative compared to fixed appliances—is of critical importance for clinical decision-making. Although the literature includes various comparative studies, there is still a need for comprehensive longitudinal research comparing clear aligners (CA) and fixed orthodontic treatment (FOT) in terms of both clinical periodontal parameters and patient-reported outcomes such as pain and quality of life. Moreover, methodological inconsistencies, small sample sizes, and limited data on mucogingival variables contribute to existing uncertainties. The primary aim of this study was to compare the effects of CA and FOT on plaque accumulation. Secondary objectives included evaluating clinical parameters such as probing depth, bleeding on probing, gingival recession, and changes in gingival phenotype, as well as the incidence of traumatic ulcerations. In addition, patient-reported outcomes such as pain level and oral health-related quality of life were assessed. A total of 64 patients were divided into two groups: CAT and FOT. Clinical parameters including full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), probing pocket depth (PPD), and gingival recession (REC) were measured at four time points (T0, T1, T2, T3). The incidence of traumatic ulceration was recorded. Gingival phenotype (gingival thickness and width of attached gingiva) was evaluated at T0 and T3. Patient-reported outcomes were assessed using the OHIP-14 questionnaire and a Visual Analog Scale (VAS). Data were analyzed using appropriate statistical methods. FMPS and FMBS were significantly lower in the CAT group compared to the FOT group. Regression analysis revealed that the variable "Groups" had a statistically significant effect on the changes in FMPS over time, explaining 31.4% of the observed variance (R² = 0.341, p < 0.001). The incidence of traumatic ulceration was higher in the FOT group. Moreover, patients treated with clear aligners reported lower pain levels and greater satisfaction. No significant changes in gingival phenotype were observed in either group during the study period. The findings indicate that CAT offers periodontal advantages over fixed orthodontic appliances. This suggests that CAT may be a preferable treatment modality for individuals with a history of periodontal disease or limited ability to maintain plaque control, supporting a personalized orthodontic treatment approach that prioritizes both patient comfort and periodontal health.