June 1, 2007 A chemical mix imitating the minerals found in saliva, but at higher concentrations, can be added to toothpaste to plug tiny pores that lead to nerves. The exposed pores lead to nerves, causing pain and sensitive teeth.
For millions of people, the sharp pain and discomfort of sensitive teeth can make your favorite hot or cold foods impossible to enjoy.
Lyndsay Bare, a third-year dental student at the University of Maryland, can relate to anyone with sensitive teeth. "I would bleach my teeth late at night, and then I'd wake up in the morning and there would be just this searing pain," Bare says. The pain can be worse by hot and cold foods or just smiling on a cold, windy day. Over the counter toothpastes don't always work well.
Now, a new ingredient in toothpaste, developed by dentists, called Novamin, can dramatically reduce teeth sensitivity. Gary Hack, DDS, a dentist from the University of Maryland says, "It's totally natural, it's non-toxic, and it's providing the same minerals that your saliva has in the oral environment, just at a higher concentration." Teeth become sensitive when gum tissue recedes, exposing a tooth's roots. Roots contain small holes or tubules that lead to nerves. Novamin plugs up the holes cutting off contact with nerves and eliminating pain. "It can also help in preventing decay. We found that it can whiten teeth and can help with periodontal or gum disease as well," Dr. Hack says. Dentists also say that drinking too much fruit juice can cause teeth sensitivity.
Novamin is found in toothpaste available from your dentist. Bare can now recommend it to her future patients. "After I used it, cold air wasn't that big of a deal, neither was drinking cold liquids," she says.
BACKGROUND: A new toothpaste ingredient has been developed by scientists at the University of Maryland's College of Dentristy. NovaMin is a material designed to relieve sensitive teeth, because blocks the holes that open in the teeth as the ceramic wears down, causing the sensitivity. And it can also help teeth absorb minerals to make them stronger and more resistant to cavities. Additional research indicates that NovaMin could help prevent cavities, too. A recent study also showed that adding NovaMin to fluoride toothpaste provided just as much benefit as increasing fluoride levels by 400% -- but without the toxicity concerns associated with too much fluoride. Novamin does this by growing new tooth mineral crystals near tiny decay cavities on the tooth surface.
HOW IT WORKS: It is a compound made from elements naturally critical for bone and tooth mineralization: calcium, phosphorus, silica and sodium. In their common forms, these elements have very limited value in tooth healthy. But in their rare ionic form, they can renew teeth. Each microscopic NovaMin particle serves as a delivery system for these ionized bioactive particles. When the particle is exposed to water -- whether it be saliva or tap water -- it instantly reacts, releasing billions of mineral ions that augment the natural remineralization process that already occurs in the mouth. These ions combine with naturally occurring ones in the saliva to form hydroxyapatite crystals. No other manmade material is known to directly lead to the formation of these crystals in the body.
ANATOMY OF A TOOTH: We think of teeth as being the part visible above the gum, but this is only the tip, or crown, of a tooth. There is also a neck that lies at the gum line, and a root, located below the gum. The crown of each tooth has an enamel coating to protect the underlying dentine. Enamel is even harder than bone, thanks to rows of tightly packed calcium and phosphorus crystals. The underlying dentine is slightly softer, and contains tiny tubules that connect with the central nerve of the tooth within the pulp. The pulp forms the central chamber of the tooth, and is made of soft tissue containing blood vessels that carry nutrients to the tooth. It also contains nerves so teeth can sense hot and cold, as well as lymph vessels to carry white blood cells to fight bacteria.
WHY TEETH HURT: Sensitive teeth are a major problem for many people. More than 80% will experience pain from hot or cold liquids and foods at some point in their life, and about a quarter will experience this sensitivity frequently. The hypersensitivity arises when the dentin of the tooth -- which is normally covered by enamel or gum tissue -- is exposed to the oral environment. Small "tubules" in the dentin can then transmit fluids that excite nerves in the pulp of the tooth, causing pain. Current toothpastes designed for sensitive teeth, like Sensodyne, use potassium nitrate compounds, which work by depolarizing nerves, which can mask more serious dental problems. The Novamin compound spread onto the tooth surface and block the dentin's tubules, dramatically reducing sensitivity.
The Materials Research Society contributed to the information contained in the video portion of this report.