The term Guided Tissue Regeneration was coined by Gottlow et al. in1986 to designate techniques that enhance selective cell population on the root surface from fibroblasts and other progenitor cells originating in the periodontal ligament. It has been defined by Chung as the creation of an environment, which following a periodontal flap procedure allows the cells from periodontal ligament to repopulate the debrided root surface area and form new periodontal...