Researchers discover new material that could make dental fillings more durable
PORTLAND, Ore., U.S.: A recent study has found that a compound used to make car bumpers more robust and protect wood decks could make dental fillings last twice as long. The results of the investigation will help design fully formulated adhesives to be tested in clinically relevant conditions, and as a result, dental patients could reduce the number of visits to the dental office.
A team of researchers at the Oregon Health and Science University (OHSU) School of Dentistry in Portland has created a filling material that is twice as resistant to breakage than conventional fillings. The new filling uses the additive thiourethane, which can also be found in protective coatings for cars and wood decks.
The team has also developed an adhesive that proved to be three times stronger after six months in use than the adhesives that are currently used to keep fillings in place. Combined, the new adhesive and the composite are designed to make more enduring dental restorations.
“Today’s dental restorations typically only last seven to ten years before they fail,” said Dr. Carmem Pfeifer, an associate professor in the Department of Restorative Dentistry at the school and corresponding author of the studies. “They crack under the pressure of chewing, or have gaps form between the filling and the tooth, which allow bacteria to seep in and a new cavity to form,” Pfeifer said. “Every time this happens, the tooth under the restorations becomes weaker and weaker, and what starts as a small cavity may end up with root canal damage, a lost tooth or even life-threatening infections,” she continued.
The dental adhesive uses a type of polymer, known as (meth)acrylamide, that is much more resistant to damage in water, bacteria and enzymes in the mouth than the standard adhesives currently used in the dental industry. The composite material uses thiourethane, a chemical compound that can better withstand chewing.
The study describing the adhesive is titled “Use of (meth)acrylamides as alternative monomers in dental adhesive systems” and was published online in Dental Materials on Feb. 27, 2019, ahead of inclusion in an issue.
The study on the material is titled “Toughening of dental composites with thiourethane-modified filler interfaces” and was published online on Feb. 19, 2019, in Scientific Reports.