TNFSF11 and periodontitis: By increasing the RANKL/OPG ratio,Dickkopf-1 shifts the balance toward enhanced osteoclasto-genesis and excessive osteoclast activity and this imbalance results inincreased resorption of alveolar bone, a hallmark of periodontitis and moreover, Dickkopf-1 has a catabolic function, as it decreasesOPG expression, further amplifying the effects of RANKL [25].