While modern dental care has made tooth decay far less of a problem than it used to be, it is still the leading cause of tooth loss. Bacteria The warm, wet interior of the mouth is a welcoming environment for bacteria, and there is no way of getting rid of them. Antiseptic mouthwashes and brushing may reduce their numbers, but the effect is only temporary. Sugar Bacteria need food to survive. The bacteria that cause tooth decay need sugar in some form.
Some people inherit teeth that are especially vulnerable to decay.
The teeth of children and adolescents tend to be more susceptible than those of adults. In later life the teeth again become more susceptible. When bacteria are allowed to remain undisturbed on the teeth for more than a day or so, they join with food debris to form a sticky film called plaque. As the bacteria digest sugar, they release acids, and plaque holds these acids firmly against the teeth. The acids dissolve the minerals in the teeth.