Some oral bacteria produce acid by-products that break down and release minerals in the tooth (demineralisation).
This weakens the enamel, but saliva helps to restore lost minerals and strengthen the tooth (remineralisation). In those with high-sugar diets and/or inadequate oral hygiene, bacteria can accumulate on the teeth in a sticky layer called plaque. When exposed to carbohydrates, plaque bacteria continuously demineralise the enamel, exceeding our ability to remineralise. A net loss of minerals occurs, leading to the destruction of enamel.
Early-stage caries presents as a white spot, or incipient carious lesion, beneath the surface of the tooth. Only, when the lesion breaks through the enamel surface, it causes a cavity in the tooth. As caries advances, the cavity can reach the dentine and, later, the pulp. This can cause severe pain for the patient, and can ultimately lead to tooth loss or abscess.
A carious lesion can form anywhere on the tooth, but it is most likely to occur on the biting surfaces (occlusal caries), in the spaces between the teeth (interproximal caries) or along the gingival margine. In patients with exposed dental roots, caries is especially dangerous, as it progresses much faster in dentine (root caries) and is harder to control.
Dental caries is the most prevalent oral disease worldwide, affecting both adults and children. It is estimated that 2.3 billion people have caries of the permanent teeth, and 530 million children have caries of the decidious teeth.
Anybody can suffer from caries. Strong preventative programs achieved a massive reduction of cavities during early childhood. In many areas in Europe, caries in children is seen in a minority of children, often associated with their socio-economic status and their parent's knowledge about oral health (constant suckling on milk bottles during night). Despite the preventative achievements during childhood, most people still suffer from cavities during their adhult life when preventative activities are reduced or new risk factors occur, such as:
- Poor oral hygiene
- Increased consumption of carbohydrates
- Frequent snacking
- Xerostomia (dry mouth)
- Radiation of head and neck (cancer treatment)
- PUFAs (visible pulp, ulceration, fistula, abscess)