Please use this link to access this publication. Abstract Introduction Cannabinoids possess anti-inflammatory, analgesic, and osteogenic effects in different cell types and tissues. The null hypothesis is delta-9-tetrahydrocannabinol (THC) might induce dental tissue repair and regeneration. The aim of this study was to investigate the effect of THC on human dental pulp cell (HDPC) viability and biomineralization as well as the molecular mechanism of THC-induced odonto/osteogenic differentiation of HDPCs. Methods The toxicity of THC on HDPCs was determined by 3-(4,5-dimethylthiazolyl-2-yl)-2,5-diphenyltetrazolium bromide assay. The odonto/osteogenic differentiation marker genes of HDPCs were assessed by real-time polymerase chain reaction with or without THC treatment. HDPC biomineralization was examined by collagen synthesis and calcium nodule deposition. The molecular mechanism of THC on HDPCs...