Although people often think of teeth as static chewing tools, a new study published in ACS Applied Materials & Interfaces shows that teeth are actually dynamic biomaterials that can retain important health information and even reveal traces of rare craniofacial diseases in childhood.
The study was led by Kyle Vining, an assistant professor at the University of Pennsylvania School of Dentistry, and the team members included former materials science master’s student Yuchen (Tracy) Jiang, pediatric dentist Dr. Kei Katsura, and pediatric genetic disease expert Dr. Elizabeth Bhoj.
They spanned materials science, dentistry, and human genetics, using the unique structure of mouse teeth to deeply explore the changes in enamel and dentin during development.
The research team pointed out that teeth are not equivalent to bones. Their composition and development mechanisms are completely different, requiring specialized methods to study. By studying the changes in enamel in mouse incisors during growth, researchers can analyze the hidden physiological and genetic information in them without sampling human teeth.
To answer the core question of “how teeth are mineralized”, the researchers boldly borrowed a geological instrument – a nanoindenter traditionally used to test the hardness of rocks. They used it to analyze the microstructure of tooth enamel.
Although teeth themselves are a complex and hard material, the sample preparation process is challenging, but once successful, researchers can use nanoindentation, scanning electron microscopy, energy spectrum analysis, Raman spectroscopy and other techniques to measure the elasticity, hardness and mineral composition of tooth enamel in detail.
The research team selected mice born 12 days as samples. At this stage, the enamel has begun to form but has not yet been fully calcified, which is convenient for precise sectioning and testing.
With these data, they further studied the model of mimicking Mendelian genetic diseases in mice, which also correspond to various craniofacial syndromes in humans.
Dr. Bhoj’s clinical experience enables the team to better correspond experimental results with actual pathological conditions, promoting the potential of teeth as an early diagnostic tool for diseases. Katsura pointed out that many rare genetic diseases do not fully consider changes in teeth and mouths, and this study is trying to fill this knowledge gap.
Although human teeth begin to develop in the fetal period, which poses an obstacle to research, the team’s method can track the structural changes of teeth throughout their growth process, which may provide new directions for revealing disease mechanisms and developing diagnostic methods.
Vining said that this interdisciplinary research not only provides new tools for understanding the process of tooth development, but may also promote new diagnostic systems in the future and even give birth to innovative materials for preventing caries.
Looking forward to the future, the team hopes to further simplify the analytical techniques currently used in the laboratory so that they can be applied in clinical dental environments to identify enamel defects, evaluate treatment effectiveness, and even predict disease risks.
Tracy Jiang said when looking back on this interdisciplinary collaboration experience: “You don’t need to master all the knowledge at the beginning. Learning from experts in different fields is one of the most valuable parts of scientific research. The most exciting discoveries often come from collaboration and collision with each other.”