Eroded dentin does not jeopardize the bond strength of adhesive restorative materials

this in vitro study evaluated the bond strength of adhesive restorative materials to sound and eroded dentin. thirty-six bovine incisors were embedded in acrylic resin and ground to obtain flat buccal dentin surfaces. specimens were randomly allocated in 2 groups: sound dentin (immersion in artificial saliva) and eroded dentin (ph cycling model - 3× / cola drink for 7 days). specimens were then reassigned according to restorative material: glass ionomer cement (ketactm molar easy mix), resin-modified glass ionomer cement (vitremertm) or adhesive system with resin composite (adper single bond 2 + filtek z250). polyethylene tubes with an internal diameter of 0.76 mm were placed over the dentin and filled with the material. the microshear bond test was performed after 24 h of water storage at 37oc. the failure mode was evaluated using a stereomicroscope (400×). bond strength data were analyzed with two-way anova and tukey's post hoc tests (α = 0.05). eroded dentin showed bond strength values similar to those for sound dentin for all materials. the adhesive system showed the highest bond strength values, regardless of the substrate (p < 0.0001). for all groups, the adhesive/mixed failure prevailed. in conclusion, adhesive materials may be used in eroded dentin without jeopardizing the bonding quality. it is preferable to use an etch-and-rinse adhesive system because it shows the highest bond strength values compared with the glass ionomer cements tested.