Effects of different dentinal drying methods on the adhesion of glass ionomer restorations to primary teeth

Glass ionomer cements that form an inevitable part of pediatric restorative dentistry are inherently sensitive to moisture. The influence of different drying techniques on the shear bond strength of glass ionomer cements to primary teeth dentin has not been established.

The purpose of the study was to evaluate the effects of different drying methods for different drying time periods on the shear bond strength of GC Fuji IX to primary tooth dentine.

A total of 135 caries-free primary teeth were selected and ground to a flat dentinal surface. Specimens were randomly divided into three groups - air dry, blot dry, and suction dry of 45 specimens each. Of these, 15 specimens each were dried for 2 s, 5 s, and 10 s. GC Fuji IX was condensed into Teflon molds, and the specimens were subjected to shear bond strength testing.

The mean shear bond strength values for the different time intervals were analyzed with analysis of variance test. In the air-dry group, the maximum shear bond strength values were obtained when the specimens were dried for 5 s and the least when dried for 2 s (P = 0.00). In the blot-dry and suction-dry groups, the highest values were obtained when the specimens were dried for 10 s and least for 2 s (P = 0.039 and 0.000, respectively).

Among the three drying methods employed in the study, the maximum shear bond strength of the glass ionomer restoration was observed in the air-dry group.