Background: To evaluate the clinical non-inferiority of injectable platelet-rich fibrin and micro-needling (iPRF +MN) with free gingival grafting (FGG) in periodontal phenotype modification therapy. Methodology: Twenty participants with a gingival thickness (GT)<0.8 mm in the mandibular anterior region were included. The participants were randomly allocated into i-PRF+MN and FGG groups. i-PRF injection was done, and MN was done with the help of a lancet in the i-PRF+MN group. The clinical parameters, i.e., GT and Keratinized tissue width (KTW), were evaluated at baseline, 3 and 6 months post-operatively. Patientreported outcomes (PROs), i.e., discomfort and esthetic satisfaction, were assessed using the visual analogue score(VAS) at one week and 3 months of re-evaluation, respectively. Results: Both groups showed a significant increase in GT and KTW with no intergroup variation (P-0.32, 0.48respectively) at the end of 6 months. However, the i-PRF+ MN group showed better PROs, i.e., less discomfort(1.11 +/- 0.60) and better esthetic satisfaction(8.77 +/- 0.44). Conclusion: The non-invasive treatment of i-PRF+MN may lead to non-inferior clinical outcomes after 6 months with better PROs compared to more invasive FGG protocols in phenotype modification therapy. (c) 2023 Elsevier Masson SAS. All rights reserved.