Change and significance of the receptor activator for NF-kB ligand and osteoprotegerin in gingival crevicular fluid in patients with chronic periodontitis

Objective:To investigate the changes and significance of the receptor activator for NF-κB ligand(RANKL) and osteoprotegerin(OPG) in gingival crevicular fluid(GCF) in patients with chronic periodontitis. Methods:Following careful sampling of CGF with standard filter strips in the 23 normal subjects and 34 patients with chronic periodontitis, the levels of RANKL and OPG were determined by enzyme linked immunosorbent assay(ELISA), and the gray scale in the periapical film was analyzed by Optimas 5.0 software. Results:There was significant difference of clinical index of periodontitis, and levels of RANKL, OPG and the ratio of RANKL/OPG in GCF between two groups(P0.01). There was a negative correlation between level of OPG and probing depth(PD)(P0.01) or attachment loss(AL)(P0.05). There was a negative correlation between the level of RANKL, ratio of RANKL/OPG and the gray scale in the periapical film (P0.05). There was no significant correlation between the levels of RANKL、OPG and the ratio of RANKL/OPG in GCF and plaque index(PLI) value and sulcus bleeding index(SBI) value. Conclusion:RANKL and OPG in GCF play an important role in the osteoclastic bone destruction in chronic periodontitis.