In the article titled, “Serum, saliva, and GCF concentration of RANKL and osteoprotegerin in smokers versus nonsmokers with chronic periodontitis”, published in elocation ID 80, vol. 5 of Advanced Biomedical Research,[1] the sentences under the subheadings “Results” and “Conclusions” in the Abstract section are incorrectly written. The correct sentences are as following:“Results: RANKL and OPG concentrations in saliva, serum, and GCF did not show any significant difference among all groups. The salivary RANKL/OPG ratio was higher in nonsmokers with periodontitis in comparison with smoker periodontitispatients (P > 0.05). Both CP groups had significantly lower serum RANKL concentrations than the healthy controls (P < 0.05).Conclusions: According to limitations of this study, it may be concluded that smoking does not affect bone resorption via the RANKL-OPG system.”