Purpose: This study was conducted to characterize clinically and radiographically the effect of using platelet-rich fibrin (PRF) autologous graft on the augmentation results of autogenous palatal bone blocks. Materials and Methods: Patients who suffered from horizontal alveolar bone defects in the anterior maxillary ridge (≤ 4.5 mm) with one or two missing teeth were augmented with autogenous palatal bone blocks 4 months prior to implant placement. PRF was used to cover the block in the test group, while only the block was used in the control. Bone width was measured with a manual caliper preaugmentation (t0), and at 0 (t1) and 4 months (t2). Cone beam computed tomography (CBCT) scans were performed at t0 and t2. Nonparametric tests (Mann-Whitney, Friedman's, and Wilcoxon signed-rank tests) were used for the comparisons. The significance level was set at P ≤ .05. Results: In the 14 sites (12 patients), all but one autograft (from the control group) integrated successfully after 4 months. No statistically significant difference was found between demographic data in the two groups. There was a statistically significant increase in the buccopalatal bone width in both groups by time as measured by CBCT as well as the manual caliper. The test group showed statistically significantly lower mean graft resorption than the control group (test, 0.8 ± 0.6 mm; control, 1.6 ± 0.9 mm; P = .006). Conclusion: Autogenous palatal bone block surface resorption is significantly decreased by the use of PRF coverage. Schlagwörter: alveolar resorption, alveolar ridge augmentation, hard palate, maxillary bone, platelet-rich fibrin