Stages of Tooth Decay

The various stages of tooth decay's destructive process, from the first acid attacks at the initial stages up to the total decay of tooth tissues and tooth loss, are the following:

The 1st Stage of Tooth Decay - White spots

Bacteria of the dental plaque metabolize carbohydrates from sugars and starch in our diet producing lactic and other acids. These acids cause the loss of calcium from the tooth enamel, through a process called demineralization of the tooth surface.

The first sign at this initial stage of tooth decay is a mild decolorization of the enamel, usually called a ‘white spot’. At this stage the tooth can remineralize and fix the weakened area itself with the help of minerals in saliva and fluoride.

The 2nd Stage of Tooth Decay - Enamel lesion

If the natural remineralisation process is unable to restore the enamel minerals lost by demineralisation, the lesion grows. Over time, the tooth enamel begins to break down beneath the surface while its surface remains intact.

Once the decay continues and breaks through the surface of the enamel, the damage is difficult to be reversed by the natural remineralization process. Possibly a fissure sealant or fluoride resin application might help prevent decay progressing. The development of a ‘brown spot’ is a sign that the tooth decay has advanced deeper in the enamel.

The 3rd Stage of Tooth Decay - Dental Cavity

Without proper control of dental plaque and sugar intake, acids will continue to dissolve the enamel and the lesion will reach the dentine. The tooth becomes sensitive to hot and cold. When enough of the sub-surface enamel is weakened by the loss of minerals, the outer layer of the enamel collapses, forming a dental cavity. The decayed area must be cleaned and the cavity filled by a dentist. At this stage of tooth decay a dental filling is required to restore the tooth and prevent further damage.

The 4th Stage of Tooth Decay - Pulp infection

Dentine is much softer then enamel and tooth decay can now reach easily the living part of the tooth, the pulp. The bacteria invade and infect the pulp of the tooth. Toothache, especially when chewing, is a classic symptom that the tooth decay has reached the pulp. The blood vessels and nerves may die due to the infection. The tooth can only be repaired with root canal treatment followed by a dental restoration. A dental crown may be required if there is extensive damage of tooth structure.

The 5th Stage of Tooth Decay - Dental abscess

Without treatment the infection can then spread through the root canals to the area of the root tips. Dying pulp tissue forms pus resulting in a tooth abscess around the root tip (periapical abscess). As the infection inside the tooth's root canal remains, the jaw bone around it gets also infected.

Swelling, bad breath and/or pus drainage are symptoms that tooth decay has reached an advanced stage and a tooth abscess has developed. The tooth pain is intense and consistent. Immediate treatment is needed.

The 6th Stage of Tooth Decay - Tooth loss

Left untreated, the tooth will be lost or have to be extracted. In cases of advanced stages of tooth decay, even if a root canal treatment is performed in combination with antibiotics, it may not be enough to eliminate the infection. In this case, tooth loss can not be avoided; the dentist will have to extract the tooth to stop the infection.

Tooth extraction may also be needed when the structural damage of the tooth is so extensive that a restoration is not viable.