Humans have two sets of teeth — primary and permanent. After milk teeth, or primary teeth, fall, permanent teeth erupt. When permanent teeth are lost, dentures are an option. However, with the advent of modern dentistry, stem cell dental implants might become the new standard of care.
Trauma or dental diseases can lead to tooth loss. However, dental implant procedures could help manage tooth loss. Dental implants replace missing or damaged teeth and their supporting structures. Tooth replacement is performed with an artificial dental prosthesis anchored to the jawbone.
Dental implants can produce several clinical complications, such as bone loss, inflammation, gum recession, and even tissue inflammation in the periodontal tissues that encircle and/or support teeth. For example, peri-implantitis, a clinical complication, is an inflammatory lesion of the mouth’s soft tissue surrounding the implant site, which can also result in loss of peri-implant supporting bone.
Another challenge is that dental implant materials do not fully imitate the physical and biological properties of actual dental materials. This may make functions such as eating and speaking difficult for patients. To overcome these kinds of dental implant limitations, researchers are developing stem cell implants.
What is a stem cell dental implant?
Stem cells are cells that divide to form other cells or tissues in the body. For example, in a stem cell dental implant, “new” teeth are generated using stem cells. In early experiments, researchers used stem cells derived from the bone marrow cells of mice to create "lab teeth". Currently, researchers combine human epithelial cells from gums with embryonic epithelial cells of 14-day-old mice. After a certain period, the combined cells that are transplanted inside the kidney capsule develop into an artificial tooth.
Eventually, the artificial teeth formed from stem cells resemble real teeth in terms of shape and size. Various parts of the tooth, including enamel, dentin, dental pulp, and bone tissue in these artificial teeth, are well developed. Although more research is needed, using these teeth is feasible and safe for humans.
Dental pulp includes a tooth’s connective tissue, nerves, and blood vessels (where your tooth hurts). Stem cells provide various advantages over other dental implantation methods. Besides being relatively easy to create, dental stem cells can help restore and regenerate vital dental pulp tissue. Dental stem cells can also form a comprehensive tooth structure, making them ideal for dental implants. Dental stem cells are an exceptional convenience for dental restorations and implants because they regenerate quickly.
Besides mouse tissue, scientists can harvest stem cells from human teeth. Regenerative medicine focuses on cell-based therapies for teeth instead of other vital organs such as the heart. Since patients with tooth problems are not usually sick, it allows scientists to explore new techniques for developing structures such as teeth.
Post-natal tooth root formation can be a rich source of dental stem cells. New odontoblasts — dental pulp’s outer layers — are produced and can be used to form new dentin. Overall, dental stem cells can provide highly compatible structures and characteristics for dental implant procedures.
Dental stem cells can be obtained from adult cells taken from patients. These cells can regenerate dental tissues and bone, including tooth enamel and pulp. In addition, it’s easy to obtain dental stem cells without invasive procedures. An in vitro study showed that dental pulp stem cells performed well in clinical trials without being toxic or damaging other cells.
Additionally, studies show that pulp stem cells adhere to dental implant surfaces well. Furthermore, teeth formed from stem cells experience tissue mineralization — the strengthening of enamel.
Challenges in dental stem cell therapy
Researchers face several challenges in developing dental stem cell therapy. New tooth quality depends on the type of stem cell used, and their delivery and introduction methods into the patient’s body. While developing implants, researchers must ensure the restoration of a tooth’s appearance and function.
The most notable challenge in using stem cell dental implants is the formation of new bone and dental ligaments. The proper connection between root tissue and tooth bone derived from stem cells must be ensured properly. Teeth created from stem cells form in different places and at different rates during tooth development.
Epithelial and mesenchymal cells are indispensable in tooth development. Therefore, this also creates a major challenge in the use of stem cells in dental implants. Identifying the source of proliferative non-embryonic stem cells needs to be accurate and thorough to form and develop new teeth properly from stem cells.
At present, researchers focus on dental stem cells from non-embryonic sources for developing implants because of ethical considerations. Embryonic stem cells require the destruction of an embryo to obtain suitable stem cells for developing tissue. That makes embryonic stem cells less attractive in stem cell research for dental implants.
Furthermore, the use of stem cells for dental implants must comply with applicable regulations. Stem cell therapy must show definite clinical evidence without harming a patient's health. The safety and efficacy of stem cell therapy must also be ascertained to determine the most appropriate treatment conditions for the patient.
Indeed, we all are looking forward to these advances in dentistry. The research is still in its early stages. However, it’s feasible that stem cell dental implants could be widely accepted and approved by regulatory bodies within a few years.
Dental implants can produce clinical complications such as inflammation, bone loss, and receding gums.
As compared to other implants, stem cell dental implants may have distinct advantages as teeth formed are biological.
This research is in its early stages but has shown promising results.
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