International Journal of Research and Reports in Dentistry

Gingival biotype—historically described as “thin” or “thick”—has evolved into the broader concept of periodontal phenotype, integrating gingival thickness, keratinized tissue dimensions, and the underlying bone morphotype. This shift reflects growing evidence that soft tissue thickness and architecture are not merely anatomic descriptors but clinically meaningful modifiers of periodontal stability, aesthetic outcomes, and complication risk across preventive, surgical, restorative, orthodontic, and implant therapies. Thin phenotypes have greater susceptibility to recession resulting from inflammation or mechanical insult, greater vulnerability to post-surgical marginal tissue changes, and an increased likelihood of aesthetic compromise when restorative or implant components shine through delicate tissue. Conversely, thicker phenotypes often demonstrate greater resistance to recession, more predictable wound stability, and improved capacity to mask restorative materials. Importantly, phenotype is not fixed; contemporary mucogingival and peri-implant soft tissue augmentation strategies can enhance gingival thickness and keratinized tissue conditions, potentially reducing risk and improving long-term stability. This narrative review synthesizes current knowledge regarding definitions, assessment methods, biologic mechanisms, and evidence-based clinical implications of gingival biotype/periodontal phenotype, emphasizing practical decision-making and interdisciplinary treatment planning. The review highlights where phenotype-based personalization is supported by clinical studies and systematic reviews, where evidence remains indirect, and how emerging digital diagnostic workflows may standardize phenotype assessment in daily practice. Current evidence supports phenotype-informed treatment planning in mucogingival surgery and peri-implant care, especially where tissue thickness is linked to early remodeling and the stability of soft tissue outcomes.