A third generation dentinal bonding system, Tenure Solution dentin bonding system, has recently become commercially available. The original system has been modified twice. The objectives of this in vitro study were to determine the shear bond strengths of the three systems to dentin 15 minutes after specimen preparation, after 24 hours storage in physiological saline at 37 degrees C with and without temperature cycling, and after 4 weeks storage with and without temperature cycling. The shear bond strengths decreased with duration of storage but of each storage interval temperature cycling had no adverse effect on shear bond strength.