New Dental Material Can Resist Biofilm Growth And Kills Bacteria

Researchers at the University of Pennsylvania have developed an antibacterial resin for dental procedures such as cavity fillings. They hope that the material can provide improved fillings that resist tooth decay and last longer.

Conventional materials for dental fillings are prone to being covered in plaque, a sticky biofilm that can lead to tooth decay and filling failure. Researchers at the University of Pennsylvania are working on developing something better. “Dental biomaterials such as these,” said Geelsu Hwang, a researcher involved in the study, “need to achieve two goals: first, they should kill pathogenic microbes effectively, and, second, they need to withstand severe mechanical stress, as happens when we bite and chew.”

Hwang and his colleagues have developed a new dental resin that contains the antimicrobial agent imidazolium. In a key development, the researchers chemically linked the antibacterial agent to the resin, so that it would not leach out into the oral cavity, but would only kill bacteria that come in contact with the resin. “This can reduce the likelihood of antimicrobial resistance,” said Hwang. This approach also means that the resin is unlikely to produce any toxicity in the mouth, but can still be effective at killing microbes on its surface.




The researchers tested the material’s ability to kill microbes and prevent the growth of biofilms, while also ensuring that it had the required mechanical strength to provide a durable filling. The material effectively killed bacteria that contacted it and permitted only small amounts of biofilm to grow on its surface.

When the team tested how much shear force was required to remove the biofilm from the material, they found that only a very small force was required to completely remove the sticky biofilm layer, whereas a force four times as strong could still not remove the biofilm from a control composite resin. “The force equivalent to taking a drink of water could easily remove the biofilm from this material,” said Hwang.