The objective of the present study was to evaluate the clinical and radiographic outcomes of intrabony defects treated with decortication (intramarrow penetration) alone versus decortication combined with platelet-rich fibrin in periodontitis patients followed up for 6 months postsurgery. A total of 46 intrabony defects from periodontitis patients with a mean age of 36.30 ± 6.10 years were randomly assigned into two treatment groups. The control group (n = 23) intrabony sites were accessed with simplified papilla preservation flap (SPPF) followed with debridement, decortication, and closure. The test group (n = 23) sites were accessed with SPPF, followed with debridement, decortication, platelet-rich fibrin placement, and closure. The clinical parameters Plaque Index, Gingival Index, probing pocket depth, relative attachment level, gingival marginal level, along with radiographic defect depth and defect width were recorded at baseline, 3 months, and 6 months postsurgery. Gain in clinical attachment level was the primary outcome, and probing pocket depth reduction and radiographic bone fill were secondary outcomes of the study. The Plaque Index and Gingival Index scores showed nonsignificant difference on intra- and intergroup comparison at baseline, 3 months, and 6 months. The probing pocket depth was 8.17 ± 1.56 mm, 6.65 ± 1.30 mm, and 5.26 ± 1.18 mm for the control group, and 8.17 ± 2.01 mm, 6.26 ± 1.42 mm, and 4.78 ± 1.28 mm for the test group, at baseline, 3 months, and 6 months, respectively. The relative attachment level was 8.83 ± 1.40 mm, 6.78 ± 1.31 mm, and 5.39 ± 1.16 mm for the control group, and 8.39 ± 1.62 mm, 6.96 ± 1.36 mm, and 5.48 ± 1.20 mm for the test group at baseline, 3 months, and 6 months, respectively. Statistically significant reductions were observed for probing pocket depth for the control (2.91 mm, P < .001) and test groups (3.39 mm, P < .001), as well as for relative attachment level for the control (3.44 mm, P < .001) and test groups (2.91 mm, P < .001). However, intergroup differences were nonsignificant for probing pocket depth and relative attachment level. The radiographic defect depth was reduced by 0.31 mm for the control and 1.57 mm for the test group. The radiographic defect width was reduced by 0.18 mm for the control and 0.83 mm for the test group. Intergroup statistically significant differences were observed at the 6-month follow-up (P < .001) for radiographic defect depth and width. Within the limitations of the present study, the results demonstrate statistically significant intragroup improvements in clinical outcomes with decortication alone and decortication combined with platelet-rich fibrin in the treatment of intrabony defects in periodontitis patients. The addition of platelet-rich fibrin did not improve the clinical results beyond decortication alone, and unacceptable postsurgery residual pockets were observed in both the protocols. Considering the small sample size, the addition of platelet-rich fibrin resulted in significant bone fill over and above that of decortication alone.