Figure 2.

Micro-tensile bond strength and failure mode. (a) Effects of desensitizer types and bonding modes on bond strength of universal adhesives. Different superscript uppercase letters indicate significant differences with etch-and-rinse mode (p < 0.05). Different superscript lowercase letters indicate significant differences with self-etch mode (p < 0.05). * denotes a significant difference between the etch-and-rinse mode and self-etch mode (p < 0.05). (b) Failure mode distribution of fracture specimens. M: mixed failure; A: adhesive failure; CD: cohesive failure within the dentin; and CC: cohesive failure within the composite resin.