If bleeding on probing (BOP) is still present after a cleaning, what might be the cause?

• A. Probing too hard
• B. Normal post-cleaning response
• C. Retained subgingival plaque
• D. Failure to remove disease-causing agents

Answer: (C)

Retained subgingival plaque is a primary cause of continued bleeding on probing (BOP) following a cleaning. Despite thorough scaling and root planing, if plaque remains below the gumline, it can prevent the healing of the periodontal tissues and perpetuate inflammation. This inflammation triggers the bleeding response when probing is applied.

When periodontal tissues are inflamed due to the presence of subgingival plaque, they become more susceptible to bleeding. Effective periodontal treatment not only involves the removal of visible plaque and calculus but also thorough cleaning of subgingival areas to ensure that no pathogenic bacteria are left behind. If retained plaque is present, it indicates incomplete debridement or an area that requires further attention, leading to persistent BOP.

Other options such as probing with excessive force, while they can cause some bleeding, typically would not result in sustained bleeding if the tissues are otherwise healthy. A normal post-cleaning response might include some transient BOP immediately after treatment due to tissue manipulation but would not account for ongoing bleeding. Similarly, the failure to remove disease-causing agents could be interpreted broadly; however, the retained subgingival plaque specifically places a direct link between persistent bacterial presence and inflammation, making it the most accurate cause of continued BOP in this scenario