The purpose of this study is to analyze the microbiota of patients undergoing orthodontic treatment with multibrackets and transparent aligners. The second goal is to evaluate the effectiveness of the oral irrigator on the oral hygiene and periodontal health of orthodontic patients. Fifty patients (27 F, 23 M; mean age 21.5 years) were recruited for the study, then divided into two groups. Group A underwent fixed orthodontic therapy with multibracket, and a home protocol that included manual orthodontic toothbrush, interdental brushes, and one-tuft brushes. Group B used transparent aligners for 22 h a day and a home protocol that included a manual brush with soft bristles and dental floss. After 3 months, all patients of the two groups, A and B, underwent plaque evaluation with a phase-contrast microscope. If the test result showed non-pathogenic bacterial flora, the subject continued with the traditional home oral-hygiene protocol. If the test detected pathogenic flora, the subject changed the home protocol, with a sonic toothbrush and oral irrigator, while the microbiological analysis continued to be performed after 3 months. After 3 months, 10 out of 25 patients treated with multibrackets (group A) and only 3 out of 25 patients with aligners (group B) passed from non-pathogenic flora to pathogenic flora. After 6 months, using the oral irrigator and a sonic toothbrush for 3 months, all subjects returned to non-pathogenic flora. This study confirms that in patients treated with multibrackets, the risk of developing unfavorable microbiota increases compared to those treated with clear aligners. The use of an oral irrigator combined with the sonic toothbrush seems to be able to restore good oral hygiene in subjects with pathogenic flora and therefore to be effective at reducing the risk of caries and gingivitis in orthodontic patients.
Keywords: clear aligners; microbiological analysis; multibrackets; oral hygiene; oral irrigator; oral prevention; orthodontics; phase-contrast microscope.