Subgingival plaque

A number of devices aid in the removal of plaque from surfaces between teeth, around bridgework, and in other areas that are difficult to reach. The limitation of many of these devices is that they are effective for control of supragingival plaque but, at best, can remove subgingival plaque only to a depth of few millimeters. Therefore, they are of minimal value against subgingival plaque located deeper within the gingival crevice, as is the case in periodontal disease. 

M. Quirynen, C.M.L. Bollen, The influence of surface roughness and surface-free energy on supra- and subgingival plaque formation in man. A review of the literature, J. Clin. Periodontol. 22 (1995) 1-14. 

Figure 35.10 The sequence of events initiated by supragingival plaque in the development of gingivitis, subgingival plaque, subgingival calculus and periodontal disease...

Dental plaque, a mass of bacteria that develops around teeth in all people, is the primary cause of dental caries and diseases of the periodontium. Following dental prophylaxis, a tooth becomes covered with a thin film, or pellicle, selectively deposited from the saliva. Bacteria in the oral cavity attach to the pellicle. The early colonizers are predominantly Gram-positive bacteria. The bacterial population increases and undergoes a predictable pattern of change as it approaches maturity. Supragingival and subgingival plaque masses... 

Collection of both supra- and subgingival dental plaque and calculus, provided the procedure is not more invasive than routine prophylactic scaling of the teeth and the process is accompHshed in accordance with accepted prophylactic techniques... 

Alexander AG A study of the distribution of supra- and subgingival calculus, bacterial plaque and gingival inflammation in the mouths of 400 individuals. J Periodontol 1971 42 21-28. 

Subgingival dental calculus. On the other hand, subgingival dental calculus is a very hard mineralized plaque which occurs on the root surface below the gum margin. It is structurally dissimilar to supragingival calculus, containing more calcium phosphate crystals, mainly as tricalcium phosphate, and fewer bacteria and is stained dark brown to greenish-black. It occurs primarily in areas that are chronically inflamed, is about 60% mineralized and it too is covered superficially with vital plaque. 

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