Effect of hydration on bond strength of a silane-bonded composite to porcelain after seven months.

Presence of moisture reduced the strength of the silane bond between each of three resin composites and porcelain significantly. The tests were run in a moist environment in vitro for seven months. Porcelain repairs in vivo are exposed to variations in temperatures and saliva. This study indicates that thermocycling alone may not be sufficient to stimulate intraoral conditions before testing shear strength of materials.