The periodontal phenotype, encompassing gingival thickness, keratinized tissue width, and alveolar bone morphology, plays a pivotal role in determining the outcomes of orthodontic treatment, particularly concerning gingival recession, post-treatment stability, and associated risks. This narrative review synthesizes evidence from peer-reviewed studies published between 2020 and 2025 to elucidate the interplay between periodontal phenotype and orthodontic interventions. Thin periodontal phenotypes are associated with heightened susceptibility to gingival recession during orthodontic tooth movement, with studies indicating increased incidence rates post-treatment compared to thick phenotypes. For instance, cross-sectional analyses reveal that thin gingival biotypes correlate with greater recession prevalence, especially in mandibular anterior regions, exacerbated by factors such as bleeding on probing and age. Longitudinal data suggest that orthodontic treatment with fixed appliances may elevate recession risk by up to 67% relative to untreated controls, though severity often remains mild. Stability of orthodontic outcomes is influenced by phenotype, as thicker gingiva and bone provide enhanced resistance to relapse and periodontal breakdown. Risk assessments highlight the importance of pre-treatment phenotype evaluation to mitigate adverse effects, with phenotype modification techniques, including soft tissue augmentation, demonstrating efficacy in preventing recession and improving long-term stability. Objectives of this review include delineating phenotype classifications, assessment methods, and evidence-based strategies for optimizing orthodontic outcomes in diverse phenotypes. By integrating multidisciplinary approaches, clinicians can minimize risks and enhance periodontal health, underscoring the need for tailored treatment protocols.
