The objective of this study was to compare bonding of acrylic resin teeth treated in various ways to the polymethyl methacrylate (PMMA) denture base material. The joint surface of each acrylic tooth cured to heat-cured or autopolymerizing PMMA was either untreated, ground, or adjusted with mechanical retention. The bond to the PMMA was tested with a three-point loading test. To determine whether the bond failure was adhesive or cohesive, the fracture surfaces were analyzed visually and by scanning electron microscopy. The highest bond strength to both the heat-cured and the autopolymerizing PMMA was obtained by grinding grooves on the joint surface of an acrylic resin tooth before it was cured to the PMMA (p0.05).