[Comparison of Shear-Peel Bond Strength of Orthodontic Cements]

Objectives: The aim of this study was to compare the shear-peel bond strength of three orthodontic cements: two resin-modified glass ionomer cements (3M Multicure Glass Ionomer and Fuji Ortho LC) and a polyacid-modified composite resin cement (Ultra Band-Lok). Methods: Cements were placed in a 3 mm diameter mold at bonding interface and bonded to 6 x 6 mm stainless steel band specimens mounted to acrylic blocks. Specimens were stored in a humidor at 37ºC for 24 hours and debonded in tension on a testing machine at 0.5 mm/minute. Bond strength (MPa) were calculated and data were analyzed by one-way analysis of variance (ANOVA) followed by a Tukey multiple comparison procedure. Results: Ultra Band-Lok (2.17 ± 1.04 MPa) demonstrated significant greater shear-peel bond strength (p<0,01) and no statistically significant differences were noted between 3M Multicure Glass Ionomer (0.10 ± 0.03 MPa) and Fuji Ortho LC (0.42 ± 0.28 MPa). Conclusions: The results indicate that the polyacid-modified composite resin cement provided higher bond strength than the resin-modified glass ionomer cements.