The incisors of a mouse grow in length throughout the animal’s life, and new enamel is created as the mouse wears down its teeth by gnawing. However, the mouse’s incisors do not form roots.
“Humans and mice have similar molars: once they begin to form a root, the stem cells that produce enamel disappear,” explains Anamaria Balic, a postdoctoral researcher at the Institute of Biotechnology.
The information about mice teeth is important because it may help researchers develop biological techniques to create new teeth for humans.
Says Balic: “The gradual process of creating tooth enamel is similar in the incisors and molars of mice, and the molars of mice develop very similarly to human molars. Once we master the process in mice, it will be very easy to apply it to humans.”
Driven by chemical stimuli
In her research, Balic isolates stem cells in mice foetuses for culturing in growth media, to which she adds various chemical stimuli, such as signalling molecules, growth factors or the body’s other natural proteins.
Through trial and error, she will eventually – so she hopes – discover which stimuli make stem cells develop into enamel-producing ameloblasts and which stimuli regulate the formation of enamel.
Answers to these questions have remained elusive because research on dental stem cells is difficult.
“Humans lose dental stem cells in early childhood, so ethical reasons prevent studies on humans,” Balic explains. “In addition, it is difficult to keep dental stem cells alive in a test tube.”
Working in the Embryonic Organ Development research group headed by Academician and Professor Irma Thessleff, Balic hopes that she will be able to move from mice cells to human ones as early as next year. She estimates that it may take a decade before the technique can perhaps be used to produce dental spare parts for humans from stem cells.
Breakthroughs with high-risk funding
At the beginning of September, the Academy of Finland granted Balic funding totalling almost 120,000 euros for 2015 and 2016 for the “generation of tooth enamel and whole teeth from stem cells in vitro and in vivo”.
Balic’s study is one of ten new projects that received high-risk funding from the Academy of Finland. The aim is to support particularly high-quality projects that involve risk-taking in terms of research.
Professor Tuula Tamminen, who chairs the Research Council for Health, says that, as competition increases, a funding instrument supporting risk-taking is needed because research funding often focuses on established research.
The ten projects in the field of health research received a total of about 1.7 million euros for a period of 16 months, after which the Council will decide whether to grant them further funding.
The University of Helsinki performed well in the pilot application for high-risk funding: it hosts seven of the ten projects that were granted funding.