The cells, which are probably responsible for the formation of human dental tissue, were found by a group of histologists and dentists of the Department of Fundamental Medicine of the School of Biomedicine of the Far Eastern Federal University in collaboration with Russian and Japanese colleagues. Researchers propose to take into account the data obtained in the development of bioengineering techniques in dentistry, aimed in particular at growing new dental tissue for patients. An article on this is has been published in the International Journal of Applied and Fundamental Research.
FEFU scientists investigated the early stages of the embryonic oral cavity development during the period wherein the teeth were laid out – from the fifth to the sixth week – using human prenatal tissues for this purpose. They managed to identify several types of cells that are involved in the formation of one of the tooth germs of the enamel organ. Among them, chromophobic cells have been identified, having an elongated spindle-shaped form, which is also responsible for the development of human teeth in the first weeks of embryo formation. The obtained data can be a fundamental basis for the development of bioengineering therapies in dentistry and gastroenterology.
Numerous attempts to use only stem cells involved in the development of enamel, dentin, and pulp – ameloblasts and odontoblasts – were not crowned with success: there is no enamel on the samples, the tooth is covered only with defective dentin. The absence of an easily accessible source of cells for growing dental tissue seriously hampers the development of a bioengineering approach to dental treatment.
“When developing technologies of tissue engineering and regenerative medicine – promising methods of treatment in dentistry – we identified the cells that may become the missing link that is necessary to reach a fundamentally new level of quality dental treatment. Implants that are completely identical to human teeth will no doubt be better than titanium ones, and their lifespan can be longer than that of artificial ones, which are guaranteed for 10-15 years. Although for a successful experiment, we still lack knowledge of intercellular signaling interactions in the development of teeth, ”said Ivan Ryeva, a senior researcher at the Laboratory for Cellular and Molecular Neurobiology at the FEFU School of Biomedicine.
The scientist noted that large chromophobic cells are present not only at the place where the embryo teeth form but also at the border, where the stratified squamous epithelium of the oral cavity passes into the cylindrical epithelium of the developing digestive tube. This means that the new bioengineering approach is relevant not only in dentistry for growing new dental tissue, but also allows growing organs for subsequent transplantation, which in the future can be successfully applied in gastroenterology.
The development of new biological approaches to the reconstruction of teeth with the use of stem cells is one of the most serious tasks in dentistry for the coming years. There are still many questions waiting for researchers on this path. For example, scientists have yet to figure out how in the early stages of the development of a human embryo from a seemingly homogeneous, and in fact, multi-layered ectoderm, which is located in the forming oral cavity, different types and forms of teeth develop. However, it is already clear that a greater number of cells are involved in the formation of a human tooth, contrary to what is considered today. Thanks to the research of FEFU scientists, it has also become clear that the crown of the tooth and its root have different formation mechanisms.
This work was supported by the FEFU Scientific Foundation, within the framework of the state task 17.5740 / 2017 / 6.7.