Xenogeneic Collagen Matrix or Palatal Connective Tissue Graft With a Coronally Advanced Flap in Class III Recessions

The purpose of this multi-center study is to compare the effectiveness of Mucograft versus connective tissue graft in combination with coronal advanced flap for the treatment of Miller class III recessions The connective tissue graft in combination with coronal advanced flap is considered the gold standard for the treatment of gingival recession in terms of percentage of root coverage and complete root coverage. However connective tissue graft harvesting from the palatal mucosa is often associated with increased patient morbidity, prolonged surgical time and is limited supply. To overcome these inconvenients many efforts are made to develop new materials (healing modifiers, barrier membranes and grafts substitutes) Recently a new two-layer , xenogenic collagen matrix (Mucograft: Geistlich Pharma , Wolhusen Switzerland) has been proposed for regenerative therapy involving teeth and implants. The use of this porcine collagen matrix has obtained promising results for treatment of Miller class I and II recession defects (isolated and multiple recession defects) The mayority of root coverage studies in the literature treats Miller class I and II recession defects .Surgical treatment of class III recesión defects is more challenging due to loss of interproximal bone and soft tissues and complete root coverage may not be expected . But some recent studies demonstrate complete root coverage and high percentage of root coverage in class III recessions. Also a new classification system using the level of interproximal attachment level has been proposed to predict the final root coverage outcome. So ,the soft tissue substitutes should be used also in Miller class III recession, and because of that fact, the investigators are conducting this study, to evaluate the effectiveness of Mucograft in Miller class III recessions compared with connective tissue graft.