Cavities (caries) are the most common cause of toothache. They are predominantly due to poor dental hygiene, which allows a sticky coating (plaque) to build up on the teeth, and the bacteria it contains convert sugars (such as glucose, fructose and lactose) into acids, which in turn erode the teeth, causing holes to form. The pain itself is due to the nerve endings being exposed.
Toothache may also be caused by gum disease or infections (e.g. abscesses), and like cavities, these are often due to plaque build-up.
Heredity may influence the tendency to develop cavities, and low saliva levels may also be involved. (Saliva aids the prevention of cavities by neutralising acids and enzymatically clearing bacteria).
Other causes of toothache may include:
It is not known why some people’s teeth are sensitive to temperature while others are not.