A comprehensive in vitro study on the performance of two different strategies to simplify adhesive bonding

Objective The purpose of this study is to compare the bonding performance and mechanical properties of two different resin composite cements using simplified adhesive bonding strategies. Materials and methods Shear bond strength of two resin composite cements (an adhesive cement: Panavia V5 [PV5] and a self-adhesive cement: RelyX Universal [RUV]) to human enamel, dentin, and a variety of restorative materials (microfilled composite, composite, polymer-infiltrated ceramic, feldspar ceramic, lithium disilicate and zirconia) was measured. Thermocycle aging was performed with selected material combinations. Results For both cements, the highest shear bond strength to dentin was achieved when using a primer (PV5: 18.0 +/- 4.2 MPa, RUV: 18.2 +/- 3.3 MPa). Additional etching of dentin reduced bond strength for RUV (12.5 +/- 4.9 MPa). On enamel, PV5 achieved the highest bond strength when the primer was used (18.0 +/- 3.1 MPa), while for RUV etching of enamel and priming provided best results (21.2 +/- 6.6 MPa). Shear bond strength of RUV to restorative materials was superior to PV5. Bonding to resin-based materials was predominantly observed for RUV. Conclusions While use of RUV with the selective-etch technique is slightly more labor intensive than PV5, RUV (with its universal primer) displayed a high-bonding potential to all tested restorative materials, especially to resin. Clinical significance For a strong adhesion to the tooth substrate, PV5 (with its tooth primer) is to be preferred because etching with phosphoric acid is not required. However, when using a wide range of varying restorative materials, RUV with its universal primer seems to be an adequate option.