Diagrammatic representation of the transplantation procedure. Representation of the experimental replantation procedure adapted from Kvinnsland et al. . (A) The right maxillary first molar is gently extracted and reflected mesially by 90° while the mesial attached gingiva is left intact. (B) It is then immediately replanted without (sham group) or with a collagen membrane placed at the base of the alveolar socket (white line) containing either saline, EGF or NGF.