Effect of adhesive strategy on resin cement bonding to dentin

Objective: The cement bonding strategy and the polymerization mode can influence the prognosis of indirect restorations. The microtensile bond strength (μTBS) and dentin endogenous enzymatic activity of a dual-cure resin cement (PV5) used in com- bination with two dentin surface conditioners (accelerator-enhancer primer, TP or universal adhesive, UA) were evaluated. Materials and Methods: PV5 was used to lute composite overlays after dentin treat- ment with TP or UA. The resin cement was self-cured, SC (1h at 37 C) or dual-cured, DC (20 s light-cure followed by 15 min self-cure at 37 C). The μTBS test, fractographic analysis, and the in situ zymography evaluations were performed after 24 h (T0) or 1 yr (T12) of artificial storage. Data were statistically analyzed (α = 0.05). Results: TP/DC obtained the highest adhesive strengths (45 ± 9 and 36.6 ± 8), while UA/SC (17 ± 8 and 11 ± 4) the lowest, both at T0 and T12, respectively. DC resulted in superior bonding values than the SC, independent of the dentin surface treatment (p < 0.05). The type of adhesive, curing mode and aging influenced the gelatinolytic activity (p < 0.05). Conclusions: The dual-cure resin cement used in combination with its accelerator- enhancer primer showed superior bonding performances with respect to universal adhesive. Dual-curing the resin cement was determinant to enhance bonding capabil- ity over time, independent of the adhesive strategy. Clinical Relevance: Clinicians must be aware to faithfully follow manufacturer's rec- ommendation regarding the adhesive strategy suggested with the resin cement used.