Stem cell research is a controversial but highly promising field of medical research. There are many possibilities for stem cell therapy to provide dramatic improvements to the repair and replacement of almost all human tissues. Dentistry is an area that is useful for the research and testing of stem cell therapy because stem cells for the area are easily harvested and patients are better suited to medical testing than those with serious health problems. This sample research paper examines how overall, dental stem cell therapy has made exciting progress and is set to make even more, but there is still a long way to go before the ultimate dream of stem cell therapy, growing replacement body parts, can be achieved.
Use of stem cells in dentistry
Stem cells are one of the most controversial things being researched by modern medical science. Their potential to help people with all kinds of illnesses and injuries is great, but so are the ethical arguments about the harvesting and testing of the different kinds of stem cells. As far as they can be researched and used, though, almost every area of medicine has an interest in stem cells. Dentistry is no exception and is, in some ways, a better field for stem cell research than any other. The potential uses of stem cells in dentistry are just as diverse as other areas of medicine and just as exciting to those who could benefit from the science, once it is fully developed. For now, most stem cell research is theoretical because of ethical and technical limits, but there are many ways those theories can be tested and applied and the entire field is moving in a very interesting direction.
Are stem cells a wonder drug?
Generally speaking, stem cells are kind of a wonder drug. They can, in theory, be used to repair or even regrow any part of the human body, since the original role of stem cells in the human body is to differentiate into any and every kind of tissue. If these powerful, versatile cells could be mastered and put to use effectively in patients, medicine could achieve feats that would have been previously called science fiction (Mouli, 2012, p. 1872). Regenerating brain cells, re-growing lost limbs, and even reversing the aging process could all be uses of stem cells in the possibly near future.
For now, the science has not progressed that far. There is not yet a cure for brain damage or old age or amputations, but some of the research being done is not so far off. Dentistry is one area of medical science that is especially suited to stem cell research and therapy. Unlike other medical fields, dentistry is not typically called for in life or death situations and dental patients are often perfectly healthy, except for their localized dental needs. These patients are much better suited to testing therapies because they are not simulations, but if something goes wrong they are much more likely to recover (Volponi, 2010, p. 716). Since the current science says that all stem cell therapy works basically the same way, by inducing stem cells to grow a certain way in vitro, and are then used to replace or repair living tissue (Mouli, 2012, p. 1872), all stem cell science could benefit from the principles developed and perfected in the relatively safe field of dentistry.
The Science Behind Stem Cells
Science has identified different kinds of stem cells, a step that has helped with some of the arguments against stem cell research. Originally, the only kind known about were embryonic stem cells which are only found in a developing human fetus (Mouli, 2012, p. 1872). There are major ethical concerns with harvesting viable human embryos, at least with many people, even though embryonic stem cells are pluripotent, that is they have the ability to turn into almost any kind of cell (Sreenivas, 2011, p. 200). Since so many other kinds of stem cells have been discovered, it seems unlikely that embryonic stem cell research will ever be allowed. Its advantages do not appear to outweigh the ethical burden of harvesting them.
The kind most commonly used and experimented on are adult, or somatic, stem cells, which have been discovered in certain adult or adolescent tissues. These are considered the best choice for dentistry, and possibly other fields, because they are easier to get and harvesting them does little or no harm to the provider (Morsczeck, 2007, p. 113). These kinds of cells have less potency than embryonic stem cells, but they are still very versatile. Somatic stem cells are classified as multipotent, meaning they can differentiate into a few different kinds of cells that are all closely related (Sreenivas, 2011, p. 200). This works very well for dentistry since it is so easy to get to the area for harvesting stem cells that are closely related to what they will be expected to repair or replace.
How Dentistry could be Improved Forever
There are a few different kinds of stem cells that can be found in the areas that would be useful for dentistry. Dental pulp stem cells (DPSCs) come from the pulpy core of teeth; periodontal ligament stem cells (PDLSCs) are harvested from the ligaments that connect teeth to the jaw bone; stem cells from apical papilla (SCAP) are found only at certain stages of development because they only exist when teeth are developing before eruption in the cells that grow into pulp and dentin; dental follicle progenitor cells (DFPCs) have this same limited window of existence and are found deeper in the area that grows into the periodontal ligament; and stem cells from exfoliated deciduous teeth (SHED) are conveniently found in, as might be guessed, deciduous teeth (Mouli, 2012, p. 1873). These many different kinds of stem cells show how many different places they can be found and the different uses they could be put to. Some are more plentiful and useful than others, but all are contributions to the science of stem cell research.
It was not easy to find or develop the science needed to manipulate these stem cells, however. Since human tooth development happens for such a limited time and then turns over immediately to decay, it was difficult for scientists to observe tooth development as it might happen in a continuous setting. Because of this, they turned to rodents. Since rodent incisors grow for their entire lives, they were the perfect example and test subjects (Morsczeck, 2007, p. 114). This made it possible for stem cell researchers to identify exactly what cells did precisely what in the growth of teeth, a process that would otherwise only be possible to observe in babies and children who cannot ethically be used for testing or taking samples.
The current and future interests of stem cell research in dentistry are fairly simple. One of the most basic uses of stem cell therapy would be to regenerate the periodontal area, the connection between teeth and jaw. Existing dental practice uses artificial materials and sometimes bone grafts to provide relatively weak and short-lived connections. Stem cell therapy could help the periodontal area heal itself in the same way that it originally developed (Volponi, 2010, p. 717). At first glance this kind of treatment could do away with expensive and painful surgeries, but it also means that those kinds of repairs would have to be made less often.
Properly repairing teeth is another major interest of stem cell research. One of the most common tooth problems is infected pulp which results in a root canal. The only way to treat these teeth, other than pulling them out, is to scrape out the bad pulp and replace it with artificial materials which kill the tooth and make it weak. Stem cells could be used to grow new pulp which could then replace the infected pulp and the tooth would stay alive and strong (Volponi, 2010, p. 718). Anyone who has ever had a root canal would probably welcome this process. While it seems to involve the same amount of discomfort, the stem cell solution would last much longer and provide a better quality of life.
The real gold medal for stem cell research is the same in dentistry as it is in other fields. Growing entirely new teeth is the ultimate goal and one that is still a ways off. Stem cell research has yet to move beyond healing existing teeth or periodontal regions (Morsczeck, 2007, p. 116), and even those are still only being tested. But the science is not unachievable. It is currently possible to grow entirely new teeth, though it so difficult and expensive that it is entirely impractical to do for any reason other than research, and even barely that, (Volponi, 2010, p. 720). Even with these limitations, dental uses of stem cell therapy are very exciting for a field that has for so long been restricted to artificial replacements for biological parts. The possibility of stem cells providing complete healing or replacement of periodontal tissue or whole teeth could improve the lives of virtually everyone.
Morsczeck, C., Schmalz, G., Reichert, T. E., Völlner, F., Galler, K., & Driemel, O. (2008). Somatic stem cells for regenerative dentistry. Clinical Oral Investigations, 12(2), 113-8. doi: 10.1007/s00784-007-0170-8
Mouli, C. P., Kumar, M. S., Senthil, B., Parthiban, S., Priya, R., & Subha, R. (2012, July). Stem cells in dentistry- a review. Journal of Pharmaceutical Sciences and Research, 4(7), 1872-1876. Retrieved September 17, 2012, from ProQuest Central (1033333140).
Sreenivas, S., Rao, A., Satyavani, S., Reddy, B., & Vasudevan, S. (2011). Where will the stem cells lead us? prospects for dentistry in the 21 st century. Journal of Indian Society of Periodontology, 15(3), 199-204. doi: 10.4103/0972-124X.85660
Volponi, A. A., Pang, Y., & Sharpe, P. T. (2010). Stem-cell based biological tooth repair and regeneration. Trends in Cell Biology, 20(206), 715-722. Retrieved October 28, 2012, from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3000521/