The width of the graft will be calculated according to the amount of tissue needed to cover the exposed roots plus mesial and distal 3mm and the amount of tissue required for the biopsy. The graft height will be the distance from the enamel cement junction (ECJ) to the buccal bone crest (Zuchelli et al., 2010). A small biopsy of the grafts (approximately 2mm x 6mm) will be removed for histomorphometric analysis. The donor area will be sutured with silk thread 4.0.