THE tooth equation is pretty simple: germs plus sugar equals acid production. These acids can dissolve enamel as well as the tooth-root structure and result in a cavity (technically, a carious lesion.) Although tooth decay is a fact of life (no record that exists ever shows that any adult human has never suffered from tooth decay), there is evidence that some persons are more resistant than others.

Since effective brushing and flossing are critical in controlling dental decay in susceptible individuals, I want to detour for a brief discussion about the cause and prevention of tooth decay. Of course, everyone who reads this column should realise by now that the secret to oral health is the effective control of dental plaque. Now, three elements need to be in place before tooth decay can happen: the microorganism responsible for decay (Streptococcus mutans) must be present, a sugar or carbohydrate for S. mutans to metabolise must be available, and the tooth or teeth must be susceptible to, or capable of decay. Additionally, there are three cavity-preventing measures those of us susceptible to tooth decay must take to combat this decay: we must control plaque, reduce carbohydrates (sugars) in our diet, and make out teeth more resistant to decay.

Eliminating or at least drastically reducing, tooth decay is certainly relatively easy although it takes a little effort. Proper brushing and flossing are of paramount importance in eliminating tooth decay in the caries-susceptible individual, because, without excellent control of plaque (the sticky stuff containing cavity-causing microorganisms, including S. mutans), cavities can develop in the grooves ( pits and fissures) of teeth, in between the teeth, on the sides of the teeth at the gum margins (edges) of fillings, crowns, or bridges distresses dentists and patients alike, since much of this restorative work was done to repair damage caused by previous decay, and new decay around existing dental work does not usually get restored properly with a patchwork approach. Once the dentist has done his or her best to restore a tooth, this work needs to be well maintained by the patient.

Brushing and flossing are critical in controlling the plaque that can lead to decay, but the further reduction of microorganisms (germs) is necessary for a healthy mouth. This can be achieved by tongue scraping (the top of most peoples’ tongue carry untold trillions of microorganisms and much odorous material), and irrigation to reduce the number of microorganisms under the gum margins.

An obvious way to cut down on dental decay is to reduce or even eliminate sugary drinks from the diet. Great plaque control is an excellent way to keep cavity-causing organisms at lower levels in the mouth, but even great plaque control is no match for the acids produced when six to twelve sugar-containing soft drinks are consumed every day; this much sugar coating the teeth supports the astronomically fast growth of the cavity-causing organism and its acids. Coffee or tea sweetened with sugar will create never-ending cavities in anyone prone to decay. The use of nonsugar sweeteners is recommended for those susceptible to tooth decay.

Another excellent way to deal with dental decay is to drink several cups of green tea a day. Why is green tea so great for reducing dental decay? One study showed that green tea inhibits the growth of plaque caused by the S. mutans bacteria, while another study showed that green tea catechins destroyed these bacteria at concentrations lower than those found in one cup of tea. Other studies report that green tea strongly inhibits bacteria after only five to ten minutes of exposure to the tea. And yet another study reported that green tea extract was more effective than fluoride compounds in preventing dental caries.

To summarise, consuming three or four cups of green tea daily for dental reasons is a great idea because it inhibits the growth of plaque caused by S. mutans, destroys the biofilm that coats teeth and the rest of the mouth (thus helping to clean the mouth), and, because of the fluoride content in green tea, actually makes the teeth more resistant to acids produced by S. mutans. Fluoride in its many dental formulations is the third method that has been utilised to reduce susceptibility to tooth decay (caries) in cavity-prone individuals. I am in my fifties and have only lost 4 teeth which occurred when I was a teenager. I ascribe much protection from green tea and recommend the same to my patients. Please note that when consuming green tea for its cavity reducing benefits, it is best to swish each mouthful of green tea vigorously to cleanse the mouth before swallowing the tea. In other words, don’t drink the tea as you normally would, since the cleansing action and the S. mutans inhibition are improved by having tea in contact with the mouth and teeth for longer periods.

Finally, my advice on the use of green tea is to find one you like, and have it readily available at work and home so you can drink it regularly. Green tea has benefits that go well beyond cavities, and you can take advantage of them all if you will incorporate drinking several cups into your normal daily routine.

A final note on the dental decay issue: make certain that you have regular dental checkups. Your dentist is there to help you be healthy. And regular dental visits afford the greatest possibility of keeping problems at a minimum.