The immunological imprint of recurrent periodontitis: From local tissue memory to central trained immunity.

Periodontitis frequently recurs after successful treatment because prior infection causes lasting changes to immune cells at both local (gingival) and systemic (bone marrow) levels, lowering their activation thresholds and creating a hyperresponsive state that perpetuates disease susceptibility upon bacterial restimulation.

A plain-English summary of the study's own findings — we don't add our own claims or interpretation. Read the full paper for the complete methods and results, and apply your own clinical judgement.