What is subgingival plaque?

Subgingival plaque refers to the accumulation of bacteria and debris that develops below the gingival margin, which is the edge of the gum tissue surrounding the teeth. This type of plaque is found in the periodontal pocket, a space that forms between the tooth and the gums in cases of gum disease. Subgingival plaque is particularly concerning because it can contribute to periodontal diseases, including gingivitis and periodontitis, which can lead to the loss of periodontal attachment and tooth loss if not properly managed.

The nature of subgingival plaque means it is more challenging to remove compared to supragingival plaque (plaque that develops above the gum line), making regular dental check-ups and professional cleanings critical for oral health. Assessing for subgingival plaque is an essential part of periodontal examinations, as it can indicate the presence of active disease.

The other options refer to different forms or locations of plaque and calculus: for instance, plaque above the gum line is known as supragingival plaque, and plaque that has hardened into calculus has undergone mineralization, becoming something that generally requires professional intervention to remove.