One of the most difficult flaps to manage is created when the vertical incision extends into the mucobuccal fold. The incision widens as the lip is retracted, and because this area is highly vascular, bleeding is excessive. Base of flap is wider than free end. The base of the flap must always be wider than the width of the free edge. This insures maximum blood supply to the flap, preventing necrosis and slough.
Periosteum is reflected as integral part of flap.
Types of Flaps used in Endodontic Surgery 1. The semilunar flap is a curved, horizontal incision with the convex portion of the incision nearest the gingival crest. Advantages of semilunar flap 1. Reduces incision and reflection time. Maintains integrity of gingival attachment 3.