[Bond durability of self-adhesive resin cement to glass ceramic].

Objective: To evaluate the bond durability of glass ceramic to self-adhesive and conventional resin cements.

Methods: Maximum water sorption and solubility of two resin cements (A: self-adhesive type, G-CEM; B: conventional type, Linkmax HV) were measured during 6 week water storage. And their surface Knoop hardness number was measured at 0.5, 24 h and 6 week after irradiation. Sixty-four glass ceramic samples were or were not silanized with one of the three silane coupling agents (A: Monobond S; B: Clearfil Ceramic Primer; C: GC Ceramic Primer), and then cemented with two resin cements. The micro-bond strength between the two cements and glass ceramic were measured at baseline and after 30 000 thermal cycle.

Results: Cement A had higher water sorption [(79.62 +/- 5.63) microg/mm³] and solubility [(4.78 +/- 3.33) microg/mm³] than cement B[(35.03 +/- 3.33) microg/mm³, (0.00 +/- 0.00) microg/mm³]. Cement A and B could achieve maximal surface hardness at 24 h after irradiation, and this was maintained during 6 week water storage. After 30 000 thermal cycle, the micro-bond strength between unsilanized glass ceramic and cement A or B was (0.00 +/- 0.00) MPa, and those between cement A and silanized glass ceramic with silane coupling agent A, B and C, were (2.86 +/- 3.25), (12.75 +/- 1.55) and (11.98 +/- 2.35) MPa respectively [for cement B, the data was (5.15 +/- 5.20), (10.94 +/- 3.30) and (14.18 +/- 3.13) MPa]. No significant diffrence was found between the micro-bond strength of cement A and that of cement B with glass ceramic.

Conclusions: Self-adhesive resin cement can achieve similar bond durability to glass ceramic as conventional resin cement does.