Self-ligating brackets exhibit accumulation of high levels of periodontopathogens in gingival crevicular fluid.

Different types of brackets seem to influence the disruption of the oral microbial environment. Therefore, the aim of this study was to evaluate the influence of self-ligating brackets on the gingival crevicular fluid levels of the putative periodontal pathogens Aggregatibacter actinomycetemcomitans sorotype a (Aaa), Tannerella forsythia, Fusobacterium nucleatum, and Porphyromonas gingivalis. Sixty samples of crevicular fluid of twenty patients (11 boys and 9 girls) were analysed at baseline (T0) and after 30 (T1) and 60 (T2) days of bonding of the self-ligating (In-Ovation®R, Dentsply, GAC or SmartClip™, 3 M Unitek, Monrovia, CA, USA) and of one conventional bracket (Gemini™, 3 M Unitek, Monrovia, CA, USA) used with elastomeric ligatures. Total DNA from samples was extracted using CTAB-DNA precipitation method and Real-time PCR was performed to analyse bacterial level. Non-parametric Friedman and Wilcoxon tests were used for data analysis (p value of < 0.05). F. nucleatum presented a different level among the different brackets at T1 (p = 0.025), the highest level in the Gemini™ bracket when compared to the SmartClip™ bracket (p = 0.043). P. ginigvalis levels increased in the In-Ovation®R (p = 0.028) at T1. The subgingival levels of bacterial species associated with periodontal disease P. ginigvalis increased in the self-ligating brackets In-Ovation®R.Clinical Relevance: Some kinds of brackets could provide more retentive sites than others, and it seems to modulate the subgingival microbiota, since, in this study, we could observe the increase of the species associated with periodontal disease. Preventive protocols should be adopted in the use of self-ligating brackets.