In recent years, the field of regenerative medicine has witnessed remarkable advancements in the use of dental stem cells. The discovery of these tiny but potent cells nestled within our teeth has sparked excitement among researchers and medical professionals alike, offering new avenues for treating a myriad of diseases and injuries.

A journey through stem cell history

Stem cells are cells that have the unique ability to develop into various specialized cell types in the body. This capacity for differentiation is what makes them invaluable in regenerative medicine.

The history of stem cell research traces back to the mid-twentieth century. In the 1960s, Canadian scientists James Till and Ernest McCulloch conducted experiments demonstrating the existence of stem cells in bone marrow, the spongy tissue inside bones that can produce blood cells, after introducing new cells into the bone marrow of irradiated mice. This work laid the foundation for further exploration into the therapeutic potential of stem cells. 

Since then, researchers have identified stem cells in various tissues throughout the body, including in dental pulp, the soft tissue inside teeth. Dental stem cells have garnered particular interest due to their easy accessibility and regenerative capabilities.

Within the dental pulp, researchers have identified several types of stem cells, each with its own unique properties and potential applications.

Dental pulp stem cells

Dental pulp stem cells (DPSCs) are stem cells found in the centre of teeth. They have unique abilities to grow and transform into different types of cells, like those found in teeth, nerves, bones, muscles, and even certain organs. These cells can help in repairing damaged teeth and treating various diseases.

DPSCs are isolated from dental pulp tissue, typically obtained from third molars, also known as wisdom teeth, that are often extracted and discarded. The isolation process does not involve invasive surgical procedures and poses no harm to the donor. 

DPSCs have the ability to repair damaged or diseased dental tissues. They can become tooth-building cells called odontoblasts — cells that form dentin, the hard tissue beneath the enamel — and osteoblasts — cells that build jaw bone. This could revolutionize dental treatments by enabling the regeneration of natural tooth structures, reducing the need for fillings, crowns, and other restorative procedures.

DPSCs may even be able to help treat several medical conditions. In nerve-related conditions, such as nerve trauma or neurodegenerative diseases, patients may experience a loss or damage of neurons that need replacement or repair. DPSCs can help as they possess the ability to differentiate into neuron-like cells. Surprisingly, they can also secrete neurotrophic factors, which are biomolecules that support the growth, survival, and function of neurons and promote neuronal repair. 

In conditions where the immune system is overactive — such as inflammatory or autoimmune diseases, or neuroinflammation in neurodegenerative diseases such as Parkinson’s disease — DPSCs can help calm down the immune system by releasing molecules that reduce viral replication and reduce inflammation produced by the immune system. 

Additionally, DPSCs have also shown promise in repairing damaged heart tissue and improving blood flow in conditions like heart attacks and leg artery blockages, including by stimulating formation and repair of blood vessels.

Stem cells from human exfoliated deciduous teeth

In 2003, researchers discovered a variety of stem cells in shed baby teeth, which are scientifically known as human exfoliated deciduous teeth. These cells have the remarkable ability to transform into various cell types like bone, nerve, and liver cells and can specialize into other types of stem cells.

When transplanted into living organisms, stem cells from human exfoliated deciduous teeth (SHEDs) show potential in repairing bone defects and forming new dental tissue. 

SHEDs also possess immune-regulating properties according to studies in mice, and they could be beneficial for treating diseases like lupus by balancing the immune response. This means that we may be able to treat lupus, which is a genetic disorder characterized by the inflammation of different tissues, with stem cells used to repair damaged nerves and slow progression. This treatment’s success is proportional to a patient’s age and duration of condition.

Immature dental pulp stem cells

In recent studies, researchers have identified a special type of dental stem cells known as Immature Dental Pulp Stem Cells (IDPSC), also found in the dental pulp of baby teeth. These cells express certain markers that indicate they are at an early stage of development and are markers in embryonic stem cells

One exciting discovery is that when researchers transplanted cell sheets made from undifferentiated IDPSC into rabbits with damaged corneas — the outermost layer of the eye — they observed the regeneration of the outer layer of the cornea. This finding suggests potential applications in treating corneal injuries and reconstruction.

Moreover, experiments involving the transplantation of IDPSC into immunocompromised mice and dogs have demonstrated promising results. The transplanted IDPSC were able to integrate well into various tissues and significantly improve conditions such as muscular dystrophy in dogs, without triggering immune rejection.

Harnessing the healing power of dental stem cells

The versatility of dental stem cells holds immense promise for regenerative medicine. Researchers are exploring a wide range of potential applications, including dental regeneration, bone regeneration, and neurological disorders.

As research continues to advance, we may soon see these tiny but mighty cells transform the landscape of healthcare, offering new hope for patients suffering from a wide range of conditions. From repairing damaged teeth to restoring neurological function, the possibilities seem to be truly endless.