A comparison of a hybrid light-cured glass-ionomer base and liner vs. a light-cured resin tooth fragment attachment.

PURPOSE The purpose of this study was to compare the dislodgement strengths and fracture types for reattached tooth fragments using a light-cured composite resin material, a hybrid light-cured glass ionomer base, and a hybrid light-cured glass ionomer liner. METHODS Seventy-five bovine incisor teeth were fractured, randomly divided into three groups of equal number, and then luted back together with three different materials (Universal Bonding Agent/TPH Composite Resin; VariGlass VLC Base; and VariGlass VLC Liner: LD Caulk Div Dentsply Int Inc, Milford, DE). The reattached fragments were subjected to thermocycling with a 40 degrees C differential and then were loaded until the force required to dislodge the fragment was reached. RESULTS The mean dislodgement strengths were 36.8 (+/- 25.6) kg for the composite resin, 36.4 (+/- 26.7) kg for the glass ionomer base, and 31.4 (+/- 29.5) kg for the glass ionomer liner. Cohesive fractures occurred in 73% of the dislodgements. CONCLUSIONS There was no statistically significant difference demonstrated (P < 0.05) between the three groups in terms of both dislodgement strength and fracture type.