Rust Remover: The Answer for Sensitive Teeth?

 A chemical that is usually used as a rust remover may also help people with sensitive teeth. A sticky patch which contains a gel layer of the chemical potassium oxalate is being tested as a treatment for people with the condition. The patch is stuck onto the painful tooth in much the same way as strips used for teeth whitening are applied, and is left in place for ten minutes.

The pain of sensitive teeth is usually triggered when fluid or food gets into the tiny holes found naturally in the surface of the teeth. Potassium oxalate is believed to work by blocking these holes. The chemical remains on the teeth and can offer relief for up to one month after a single application. The pain of sensitive teeth is typically triggered when fluid or food gets into the tiny holes found naturally in the surface of the teeth.

One in ten people has sensitive teeth, also known as dentine hypersensitivity. It causes short bouts of sharp pain that can be triggered by a number of factors, from cold air to food or drinks that are particularly hot, cold or sweet.Although the pain is of short duration, it can affect quality of life as those affected have to avoid these every day triggers.

Sensitivity occurs when dentine, the tissue that forms the bulk of a tooth, is exposed. Usually dentine is protected by an outer layer of enamel, but as a result of brushing too hard, gradual erosion from acidic food and drinks or ageing, this layer can wear away, exposing the tiny holes in dentine.

This most commonly happens at the point where the tooth and the gum meet because the enamel layer there is much thinner. Still, the dentine may also be exposed as a result of gum recession, where the gums pull back from the tooth surface, often because of gum disease. This then exposes the root surfaces of the teeth and nerves. Dentine is similar in composition to bone but is perforated with many tiny holes that contain nerve fibers – when exposed, these transmit pain signals. Toothpastes or mouth rinses that contain chemical salts and fluoride can help by blocking these tubules to stop trigger substances getting through.

A major advantage of this new patch is that potassium oxalate does not dissolve in the mouth and remains active for up to a month.

In the new study at Bristol Dental Hospital, dentists are using a strip with a gel containing potassium oxalate, a chemical used in industry for removing rust, bleaching woods and removing scale from car radiators. Research so far has shown that the chemical has a desensitizing effect by physically blocking exposed tubules.

In the new trial involving 100 patients with sensitive teeth, half will apply the strip (which is large enough to cover two teeth at a time) for ten minutes, or use a toothpaste for sensitive teeth.  Sensitivity will be measured throughout the month-long trial and scans will be taken to see whether tubules are exposed.

Commenting on the new research, Damien Walmsley, a professor of restorative dentistry at the University of Birmingham and scientific adviser to the British Dental Association, says: ‘It a very interesting idea. They seem to have found a chemical which blocks the tubes and which seems to work.