Plaque and Calculus (Tartar)

Dental plaque is a usually clear colour film of bacteria and food debris that builds up on the teeth. If not removed regularly, it can lead to gum inflammation (gingivitis), tooth decay and periodontal disease.
The bacteria present in dental plaque are all naturally present in the oral cavity, and are normally harmless. However, failure to remove plaque by regular tooth brushing means that they are allowed to build up in a thick layer. Those bacteria nearest the tooth surface convert food particles to acids which damage the adjacent tooth surface leading to tooth decay (caries). Saliva can’t penetrate the build-up of plaque to neutralize the acid and damage produced by the bacteria.

Plaque accumulation also causes the gingivitis in which the gums become irritated and inflamed. Gingivitis can be recognized as the gums take on a more crimson colour, and tend to bleed very easily, especially when brushing your teeth. When the gingiva become so irritated, damage can occur to the bone that surrounds the tooth; this is known as periodontal disease. Plaque that remains in the oral cavity long enough will eventually calcify and become calculus (tartar). Calculus is harmful to gingival health because it contains living bacteria which are impossible to remove with a toothbrush. In addition, it has a rough surface, which allows attachment of more plaque bacteria as well as stains easily.
Calculus formation can result in a number of clinical problems, including bad breath, receding gums and chronically inflamed gingiva.