Effects of fixed orthodontic treatment and two new mouth rinses on gingival health: A prospective cohort followed by a single-blind placebo-controlled randomized clinical trial

Routine brushing protocols might not suffice to reduce the increased plaque accumulation in orthodontic patients. Antimicrobial mouth rinses are favorable in this regard. This two-phase study evaluated the effects of orthodontic treatment and the application of two mouthwashes not studied before on oral health indices.In this two-phase study (a prospective cohort followed by a parallel randomized controlled trial), plaque index (PI), gingival index (GI), gingival bleeding index (GBI), and pocket probing depth (PPD) were measured in 54 orthodontic patients before orthodontic treatment and 4 months later. Then patients were randomized into three groups of mouthrinses: Persica (herbal), Ortho-Kin (containing diluted chlorhexidine), and Placebo (n=18×3). The effects of orthodontic treatment and mouthrinses were analyzed statistically (α=0.05).All the 4 indices increased between the baseline and 4th month of treatment (P values0.01, paired t-test). They decreased back to baseline levels or below them, after one month of mouthwash application (P values0.002). Both mouthwashes showed therapeutic effects compared to placebo in terms of PI and GBI. In the case of GI, only Persica showed significantly better results compared to placebo. Regarding PPD, only Ortho-Kin acted better than placebo (P values≤0.05, Tukey).Lack of positive control (regular chlorhexidine mouth rinse) and negative control (a group with no mouthwashes, even without the placebo). Lack of sample size predetermination based on a priori power calculations. The difference between the regime of Persica with that of Ortho-Kin and placebo (which had similar application protocols) disallowed perfectly effective blinding of the patients (hence, single-blind).Fixed orthodontic treatment might disrupt gingival health. Antimicrobial mouthwashes might reverse this. Both evaluated mouthwashes might have therapeutic effects.