varies by location in the mouth. Examples of such anaerobes include fusobacterium and actinobacteria. S. mutans and other anaerobes are the initial colonisers of the tooth surface, and play a major role in the establishment of the early biofilm community. Streptococcus mutans uses the enzyme glucansucrase to convert sucrose into a sticky, extracellular, dextran-based polysaccharide that allows the bacteria to cohere, forming plaque. (Sucrose is the only sugar that bacteria can use to form this sticky polysaccharide). These microorganisms all occur naturally in the oral cavity and are normally harmless. However, failure to remove plaque by regular tooth-brushing allows them to proliferate unchecked and thereby build up in a thick layer, which can by virtue of their ordinary metabolism cause any of various dental diseases for the host. Those microorganisms nearest the tooth surface typically obtain energy by fermenting dietary sucrose; during fermentation they begin to produce acids. The bacterial equilibrium position varies at different stages of formation. Below is a summary of the bacteria that may be present during the phases of plaque maturation: Early biofilm: primarily Gram-positive cocci Older biofilm (3–4 days): increased numbers of filaments and fusiforms 4–9 days undisturbed: more complex flora with rods, filamentous forms 7–14 days: Vibrio species, spirochetes, more Gram-negative organisms Dental plaque as a biofilm Dental plaque is considered a biofilm adhered to the tooth surface. It is a meticulously formed microbial community, that is organised to a particular structure and function. Plaque is rich in species, given the fact that about 1000 different bacterial species have been recognised using modern techniques. A clean tooth surface would immediately be colonised by salivary pellicles, which acts as an adhesive. This allows the first bacteria (early colonisers) to attach to the tooth, then colonise and grow. After some growth of early colonisers, the biofilm becomes more compliant to other species of bacteria, known as late colonisers. Early colonisers mainly Streptococcus species (60–90%) Eikenella spp. Haemophilus spp. Prevotella spp. Propionibacterium spp. Capnocytophaga spp. Veillonella spp. Late colonisers Aggregatibacter actinomycetemcomitans Prevotella intermedia Eubacterium spp. Treponema spp. Porphyromonas gingivalis Fusobacterium nucleatum is found between the early and late colonisers, linking them together. Some salivary components are crucial for plaques ecosystem, such as salivary alpha-amylase which plays a role in binding and adhesion. Proline-rich proteins (PRP) and statherins are also involved in the formation of plaque. Supragingival biofilm Supragingival biofilm is dental plaque that forms above the gums,