New Delhi: Japanese researchers have identified two distinct stem cell lineages responsible for forming tooth roots and alveolar bone, a discovery that could open the door to regenerative dental therapies.
The team from the Institute of Science Tokyo used genetically modified mice and lineage-tracing techniques to study how stem cells differentiate during tooth development.
“Our findings provide a mechanistic framework for tooth root formation and pave the way for innovative stem-cell-based regenerative therapies for dental pulp, periodontal tissues, and bone,” said Mizuki Nagata, Assistant Professor in the Department of Periodontology at the institute.
The ability to regenerate lost teeth and surrounding bone has long been regarded as a major goal in dentistry. For decades, replacement has relied on artificial solutions such as implants and dentures, which, while effective, cannot fully replicate the structure, function or feel of natural teeth.
Published in Nature Communications, the studies visualized and tracked tooth development in mice, leading to the identification of a previously unknown mesenchymal progenitor cell population. The researchers mapped two separate lineages: one linked to tooth root development and the other to alveolar bone formation.
The first lineage, originating in the apical papilla of the epithelial root sheath, was found to express CXCL12, a protein crucial in bone formation within bone marrow. Through the canonical Wnt signalling pathway, these cells were shown to differentiate into odontoblasts, cementoblasts, and, under regenerative conditions, osteoblasts forming alveolar bone.
The second lineage, concentrated in the dental follicle, the sac-like structure surrounding a developing tooth, comprised cells expressing parathyroid hormone-related protein (PTHrP). These were found to differentiate into cementoblasts, ligament fibroblasts, and osteoblasts.
According to the researchers, the findings provide valuable insights into how teeth and alveolar bone develop in living organisms, offering a potential blueprint for future regenerative treatments.