Aim– The aim of the study to assess the ability of Nigella sativa seed extract in the treatment of periodontal intrabony defects by clinical and radiographical analysis. Methodology–Twenty patients with intrabony defects were divided into two groups. Group I patients received open flap debridement only whereas group II patient underwent open flap debridement along with placement of Nigella sativa seed extract into the intrabony defect. Gingival index, plaque index, probing pocket depth, clinical attachment level and Radiographs were taken preoperatively and six months postoperatively. Result– The results indicated that Nigella sativa seed extract produced favourable changes in terms of soft and hard tissue which were assessed both clinically and radiographically. Conclusion–This clinical study concluded that the Nigella sativa seed extract can be used as a herbal bone formative material in periodontal intrabony defects