THC Stimulated Dental Pulp Cells to Form Bone-Like Tissue in a Lab — a Surprising Finding for Tooth Repair

In a finding that surprised even the researchers (their null hypothesis was that THC would induce dental tissue repair), THC showed biphasic effects on human dental pulp cells. Low doses (5 μmol/L) stimulated cell proliferation, while higher concentrations showed different patterns.

More importantly, THC upregulated odonto/osteogenic marker genes — the genetic signals that tell pulp cells to differentiate into cells that produce dentin and bone-like tissue. THC-treated cells showed increased collagen synthesis and calcium nodule deposition, meaning they were actually forming mineralized tissue.

The mechanism worked through both CB1 and CB2 receptors and involved the MAPK signaling pathway — a well-characterized growth and differentiation cascade. Blocking either cannabinoid receptor reduced THC's pro-mineralization effects. THC showed no toxicity to the cells at concentrations up to 100 μmol/L.

Nobody is suggesting smoking cannabis for better teeth. But at the cellular level, this study showed that cannabinoid receptors on dental pulp cells can be activated to promote tissue mineralization. If this can be harnessed pharmacologically — perhaps through a localized application of cannabinoid compounds directly to exposed pulp — it could represent a new approach to dental tissue regeneration.

The broader significance is that cannabinoid receptors keep showing up in tissues and biological processes where nobody expected them, expanding the potential medical applications of cannabinoid science far beyond the brain.