During periodontal surgery, the gums are lifted away from the roots of the teeth so the bacteria that cause gum disease can be visualized and removed. If the bone supporting the teeth is damaged, it is smoothed to improve healing. Depending on the shape of the defects in the bone, sometimes the damage can be reversed by grafting the defects with bone or regenerative materials. The gums are then sutured back against the teeth, resulting in a tighter seal and reduced pocket depth. The process requires only local anesthesia.