Oral bio‑modulation with probiotics during fixed orthodontic treatment: A scoping review of clinical and microbiological outcomes

Existing research has focused on individual probiotics with limited impetus placed on clinical outcomes; this has left a void on the broader landscape of probiotic-based interventions in orthodontics.To address this gap, the present scoping review was conducted to systematically map available clinical evidence on the use of probiotics during fixed orthodontic therapy, including probiotic strains and delivery systems, clinical and microbiological outcomes, and methodological and evidence gaps in the current literature.A scoping review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines.For this purpose, electronic databases were searched for clinical studies evaluating probiotic interventions in patients undergoing fixed orthodontic treatment.Animal and in vitro studies, case reports, case series, reviews and studies without comparative clinical or microbiological outcome data were excluded.Data regarding study characteristics, probiotic strains, delivery systems, intervention characteristics, clinical and microbiological outcomes, adverse effects, and methodological quality were charted and descriptively synthesized.As demonstrated by the findings of the present scoping review, probiotic interventions may provide benefits for selected microbiological, gingival, periodontal and patient-centered outcomes during fixed orthodontic treatment; however, the available evidence is heterogeneous and inconsistent across probiotic strains, delivery systems and outcome domains.In summary, the current evidence is insufficient to support definitive recommendations for routine clinical use.Further well-designed randomized controlled trials with standardized interventions and clinically relevant long-term outcomes are required.