Dr. Hao Fong and his research group are using a $64,905 grant from the National Institutes of Health/National Dental and Craniofacial Research to fund the first year of a two-year research project. Fong's research focuses on improving the polymer composite fillings already in use, despite their drawbacks. Polymer fillings stain, shrink and wear much more quickly than silver fillings, so they must be replaced in a fraction of the time.
Fong is an assistant professor in Tech's Department of Chemistry and Chemical Engineering, and he is one of the leading scientists nationwide in the field of "electrospinning and nanofibers."
"Improving the mechanical properties and reducing internal stresses have been among the major research efforts for polymeric dental restorative composites for decades," Fong said. "If successful, this research may lead to the next generation dental restorative composite filling material, which will eventually benefit everyone who needs to repair a tooth cavity."
To accomplish that, Fong is using electrospun polymer nanofibers to create the filling material. Electrospinning is a technology that produces unique polymer nanofibers with diameters typically in the range from 50 nanometers to 500 nanometers. The diameter of a human hair is 4,000 times greater than that of a nanofiber.
The electrospun polymer nanofibers possess extraordinary structural perfection and are mechanically strong. The finished material will be white to match the tooth it fills.
The research is important because traditional fillings -- called amalgams -- have created controversy over the years. Most people recognize dental amalgams as silver fillings. Dental amalgam is a mixture of mercury, and an alloy of silver, tin and copper.
Mercury generally makes up 45 to 50 percent of the compound, and is used to bind the metals together and to provide a strong, hard, durable filling. After years of research, mercury has been found to be the only element that will bind these metals together in such a way that can be easily manipulated into a tooth cavity.
However, some people believe that the mercury in tooth fillings can cause medical problems, including kidney, intestinal, neurological, fertility, heart, and other concerns.
The nanofiber research being conducted by Dr. Fong and his associates at South Dakota Tech will go a long way toward the elimination of these health worries.