The aim of the study was to evaluate clinical response of the hydroxyapatite as graft materials in the periodontal bony defects due to localized developmental tooth anomalies. Systemically healthy Male patient age 32 with a recurrent gingival swelling in relation to upper left side of tooth. Clinically there was periodontal pocket probing depth of 9mm (Williams marking periodontal probe) in relation to maxillary left lateral incisor │2 due to presence of palatal groove. The lesion was treated surgically with the application of hydroxyapatite (HA) as grafting material without membrane. Clinical response of the tissue, regenerative potentiality and effectiveness of hydroxyapatite as a bone graft material for the treatment of periodontal intrabony lesion was observed. Pre and Postoperative treatment like bleeding on probing, probing depth, clinical attachment level, gingival recession was observe after periodontal therapy and Intra-Oral Periapical radiograph was also compared before and after 6 months of therapy. The present case shows that there is decrease in depth of periodontal pocket, increases in clinical attachment level, and increase in gingival recession, no bleeding on probing and presence of bone formation in the post operative Intra-Oral Periapical radiograph was found. From the present study it’s concluded that hydroxyapatite (HA) can acts as effective bone graft substitute materials for the treatment of periodontal intrabony bony defect.