Periodontal health in teenagers treated with removable aligners and fixed orthodontic appliances

Objectives: To explore the microbiological and periodontal changes occurring in adolescents during 12 months of orthodontic therapy with removable aligners (Invisalign®) and with fixed appliances. Subjects and Methods: During the years 2012-2013, 50 teenagers aged 10-18 years with similar orthodontic starting conditions participated in this trial in a university clinic of northern Italy. After receiving professional oral hygiene and instructions on a standardized oral hygiene protocol, the adolescents were randomly assigned to either orthodontic treatment with traditional fixed brackets (n=25) or to treatment with Invisalign® aligners (n=25). Subgingival microbiological samples, probing depth (PD), plaque index (PI), and bleeding on probing (BOP) were recorded from the mesiovestibular subgingival sulcus of the upper right first molar and left central incisor at the beginning of treatment and 3, 6, and 12 months later. Compliance to oral hygiene procedures, full mouth plaque score (FMPS) and full mouth bleeding score (FMBS) were assessed at the beginning of treatment and 12 months later. Two sample independent t-tests and Chi-square test were used to study whether the indices of periodontal health differed for the teenagers by experimental conditions. Results: None of the patients resulted positive for the periodontal anaerobes analyzed. PI, PD, BOP, FMPS and FMBS resulted significantly lower and compliance to oral hygiene resulted significantly higher in the group treated with Invisalign® compared to the group treated with fixed brackets. Conclusion: Teenagers treated with removable appliances show better compliance to oral hygiene,