Pocket Reduction Surgery Pocket reduction surgery (also known as gingivectomy, osseous surgery and flap surgery) is a collective term for a series of several different surgeries aimed at gaining access to the roots of the teeth in order to remove bacteria and tartar (calculus). The human mouth contains dozens of different bacteria at any given time. The bacteria found in plaque (the sticky substance on teeth) produce acids that lead to demineralization of the tooth surface, and ultimately contribute to periodontal disease. Periodontal infections cause a chronic inflammatory response in the body that literally destroys bone and gum tissues once they invade the subgingival area (below the gum line). Gum pockets form and deepen between the gums and teeth as the tissue continues to be destroyed. Periodontal disease is a progressive condition which, if left untreated, causes massive bacteria colonization in gum pockets and can eventually cause teeth to fall out. Pocket reduction surgery is an attempt to alleviate this destructive cycle, and reduce the depth of the bacteria-harboring pockets.