Changes

Dental plaque is a biofilm composed of aggregates of [[:Category:Bacteria|bacteria]] and their by-products, salivary components, oral debris, and occasional epithelial and inflammatory cells. Plaque accumulation starts within minutes on a clean tooth surface. The initial accumulation of plaque occurs supragingivally but will extend into the sulcus and populate the subgingival region if left undisturbed. The formation of plaque involves two processes, namely the initial adherence of bacteria and then the continued accumulation of bacteria due to a combination of bacterial multiplication and further aggregation of bacteria to those cells that are already attached.  

Dental plaque is a biofilm composed of aggregates of [[:Category:Bacteria|bacteria]] and their by-products, salivary components, oral debris, and occasional epithelial and inflammatory cells. Plaque accumulation starts within minutes on a clean tooth surface. The initial accumulation of plaque occurs supragingivally but will extend into the sulcus and populate the subgingival region if left undisturbed. The formation of plaque involves two processes, namely the initial adherence of bacteria and then the continued accumulation of bacteria due to a combination of bacterial multiplication and further aggregation of bacteria to those cells that are already attached.  

As soon as a tooth becomes exposed to the [[:Category:Oral Cavity - Anatomy & Physiology|oral cavity]], its surfaces are covered by the '''pellicle '''(an amorphous coating of salivary proteins and glycoproteins). The pellicle alters the charge and free energy of the tooth surfaces, which increases the efficiency of bacterial adhesion. Certain specific bacteria can adhere directly to the pellicle. These bacteria produce extracellular polysaccharides, which then aggregate other bacteria that are not otherwise able to adhere. The plaque associated with healthy [[Gingiva|gingiva]] is mainly comprised of aerobic and facultative anaerobic bacteria. As gingivitis develops, plaque extends subgingivally. Aerobes consume oxygen and a low redox potential is created, which makes the environment more suitable for the growth of anaerobic species. The aerobic population does not decrease, but with increasing numbers of anaerobes, the aerobic/anaerobic ratio decreases. The subgingival florae associated with periodontitis are predominantly [[:Category:Anaerobic bacteria|anaerobic bacteria]].  

As soon as a tooth becomes exposed to the [[:Category:Oral Cavity - Anatomy & Physiology|oral cavity]], its surfaces are covered by the '''pellicle '''(an amorphous coating of salivary proteins and glycoproteins). The pellicle alters the charge and free energy of the tooth surfaces, which increases the efficiency of bacterial adhesion. Certain specific bacteria can adhere directly to the pellicle. These have recently been shown to be mostly members of the genus ''Neisseria'' in dog plaque. These bacteria facilitate the recruitment of secondary bacterial species to the developing plaque biofilm. The plaque associated with healthy [[Gingiva|gingiva]] has a higher proportion of aerobic and facultative anaerobic bacteria. As gingivitis develops, plaque extends subgingivally. Aerobes consume oxygen and a low redox potential is created, which makes the environment more suitable for the growth of anaerobic species. The aerobic population does not decrease, but with increasing numbers of anaerobes, the aerobic/anaerobic ratio decreases. The subgingival florae associated with periodontitis are predominantly [[:Category:Anaerobic bacteria|anaerobic bacteria]].  

Dental calculus (tartar) is mineralized plaque. However, a layer of plaque always covers calculus. Both supragingival and subgingival plaque becomes mineralized. Supragingival calculus per se does not exert an irritant effect on the gingival tissues. The main importance of calculus in periodontal disease seems to be its role as a plaque-retentive surface. This is supported by well-controlled animal and clinical studies that have shown that the removal of subgingival plaque on top of subgingival calculus will result in healing of periodontal lesions and the maintenance of healthy periodontal tissues.

Dental calculus (tartar) is mineralized plaque. However, a layer of plaque always covers calculus. Both supragingival and subgingival plaque becomes mineralized. Supragingival calculus per se does not exert an irritant effect on the gingival tissues. The main importance of calculus in periodontal disease seems to be its role as a plaque-retentive surface. This is supported by well-controlled animal and clinical studies that have shown that the removal of subgingival plaque on top of subgingival calculus will result in healing of periodontal lesions and the maintenance of healthy periodontal tissues.