COMPARISON OF ORAL HYGIENE STATUS AND GINGIVAL HEALTH BETWEEN PATIENTS WEARING FIXED ORTHODONTIC APPLIANCES AND CLEAR ALIGNERS: A COMPARATIVE CROSS-SECTIONAL STUDY

Abstract

Background: Orthodontic treatment can influence oral hygiene and gingival health due to changes in plaque retention, oral hygiene practices, and access to tooth surfaces. Fixed orthodontic appliances may create additional plaque-retentive areas around brackets and archwires, potentially increasing the risk of gingival inflammation. Clear aligners, in contrast, are removable and may facilitate oral hygiene procedures, although their use can also alter the oral environment. Comparing oral hygiene status and gingival health between patients using these two treatment modalities can provide valuable insight into their effects on periodontal health. Therefore, this study aimed to compare oral hygiene status and gingival health among patients wearing fixed orthodontic appliances and clear aligners. To compare oral hygiene status and gingival health between patients undergoing orthodontic treatment with fixed appliances and those using clear aligners.

Methods: This comparative cross-sectional study included 176 orthodontic patients aged 13–31 years (110 with fixed appliances and 66 with clear aligners) at Saidu Group of Teaching Hospital, Swat, Khyber Pakhtunkhwa, Pakistan from January 2025 to June 2026. Participants completed a structured questionnaire on demographics, treatment characteristics, oral hygiene practices, diet, tobacco use and gingival symptoms, followed by a clinical examination recording the Silness–Löe plaque index, Löe–Silness gingival index, bleeding on probing, probing pocket depth, calculus and white spot lesions. Groups were compared using the Mann–Whitney U test and chi-square tests, and multivariable linear regression adjusted for age, sex, treatment duration and hygiene behaviors. Significance was set at p<0.05.

Results: The fixed appliance group had higher mean plaque index (1.80±0.53 vs. 1.44±0.61; mean difference 0.36, 95% CI 0.18–0.54; p<0.001) and gingival index (1.44±0.47 vs. 1.15±0.47; mean difference 0.29, 95% CI 0.15–0.44; p<0.001). Bleeding on probing (74.5% vs. 45.5%, p<0.001), calculus (56.4% vs. 37.9%, p=0.018) and white spot lesions (35.5% vs. 18.2%, p=0.035) were more frequent with fixed appliances, whereas probing pocket depth did not differ significantly (2.44±0.46 mm vs. 2.32±0.43 mm; p=0.091). Self-reported brushing, interdental cleaning, mouthwash use and professional cleaning were similar between groups. After adjustment, clear aligner use remained independently associated with lower plaque (β=−0.34, 95% CI −0.51 to −0.16) and gingival (β=−0.30, 95% CI −0.44 to −0.15) index scores. Overall, 63.6% of participants had poor hygiene status and only 4.0% had clinically healthy gingiva.

Conclusion: Patients with clear aligners had significantly better plaque control and gingival health than those with fixed appliances, independent of measured hygiene behaviors, although hygiene was suboptimal in both groups. Appliance-specific oral hygiene reinforcement is recommended for all orthodontic patients.