Methods: Forty cylinder glass ceramic blocks (E-max Press) measuring 4 mm in diameter and 2 mm in height were etched with hydrofluoric acid, then divided into 4 groups (n=10) receiving 4 different silane treatments: Negative control - no silane treatment (C), treated with either silane-pure-containing primer RelyX Ceramic Primer (RX), silane-and-MDP-containing adhesive Single Bond Universal Adhesive (SU) or silane-and-MDP containing primer (MP).