Compomers and glass ionomers: bond strength to dentin and mechanical properties.

PURPOSE

To compare compomers and conventional and resin-modified glass ionomer cements (GIC) with respect to bond strength to dentin and mechanical properties.

MATERIALS AND METHODS

Seven conventional GICs (BaseLine, ChemFil Superior, Fuji II, Fuji IX, Ketac-Fil, Ketac-Silver, and Miracle Mix), three resin-modified GICs (Fuji II LC, Photac-Fil, and Vitremer), and two compomers (Dyract and Compoglass) were investigated. Bond strength was determined to untreated as well as pre-treated human dentin. The mechanical properties tested were flexural strength and flexural modulus.

RESULTS

Mean bond strengths to untreated dentin ranged from 0.0 MPa (Photac-Fil) to 8.5 MPa (Fuji IX). Generally, the bond strengths of the compomers and resin-modified GICs were lower than those of the conventional GICs. Mean bond strengths to pre-treated dentin ranged from 0.5 MPa (Photac-Fil) to 13.7 MPa (Compoglass). No clear-cut bond strength pattern was observed for the three types of materials. Pretreatment improved the bond strength of nine out of 12 materials. Flexural strengths ranged from 13 MPa (Miracle Mix) to 180 MPa (Dyract). Generally, the compomers were stronger than the resin-modified GICs, which were much stronger than the conventional GICs. Flexural moduli ranged from 4.0 GPa (Miracle Mix) to 7.2 GPa (Fuji IX and Dyract) with no typical variations between the three categories of materials.