14 DAY TRIAL // Chewing produces a mix of bacteria, acidity and abrasion in your mouth that gives no chance to your teeth.
If genetics cannot help, dentists even less. And the filling employed by dentists cannot be as hardy as the natural teeth. Moreover, secondary decay may grow where the filling attaches to the tooth. 70 % of all dental interventions represent replacements of the previous repairs. Only in US, this represents about $5 billion yearly.
Now, a team at the American Dental Association's Paffenbarger Research Center, has employed nanotechnology in tooth restorations, achieving both stronger and more effective at preventing secondary decay fillings than those currently available.
The team used standard composite resin filling, which gives a natural-looking restoration. The filling is usually made by joining the pure liquid resin with a powder including coloring, reinforcement and other chemicals. The resulting paste is introduced into the cavity, and a light source will make the paste polymerize and harden.
The mixture also contains an additive offering a steady release of calcium and phosphate ions, with the role of hardening the teeth's crystal structure and acting against the decay-provoking acidity induced by bacteria in the mouth.
But this is the Achilles' heel of the current technique: the ion-releasing chemical is structurally weak, and exposes the filling to secondary decay.
The Paffenbarger team has developed a spray-drying technique employing particles of several ion-releasing chemicals, like dicalcium phosphate anhydrous (DCPA), with diameters of roughly 50 nanometers, 20 times less than the 1 micron diameter of the currently employed DCPA powder.
The nanoscale particles possess a much higher surface related to its volume ratio, which means it releases ions more effectively, thus less material is needed. This way, the filling is more resistant as it contains more resin.
The same team also has made nanoscale silica-fused fibers for a composite resin almost twice as strong as the currently employed one.