PVT1 and pulpitis: Our above results are consistent with the expression of PVT1 in pulpitis reported recently by Lei et al.12 LPS is an endotoxin derived from gram-negative bacteria and is often used to establish the in-vitro and in-vivo models of inflammation and infection.24 In this study, the in-vitro pulpitis cell model was successfully constructed by LPS stimulation on hDPCs, which was accompanied by suppression of cell proliferation, and acceleration of cell apoptosis and inflammatory reaction.