Preparation and characterization of UV-Curable phosphate ester-containing acrylate resin adhesive for dental zirconia restorations

Fumed silica was utilized as a filler, methacryloyloxydecyl dihydrogen phosphate (MDP) served as a reactive monomer, and acrylate acted as a resin monomer to develop zirconia adhesives for dental acrylate resins containing phosphate esters. A uniform design, orthogonal tests, and single-variable experiments were conducted to vary the composition of each component. The effects of different composition ratios on the mechanical properties, hydrophilicity, flowability, and volumetric shrinkage of dental resin adhesives were studied in detail. The resin matrix composition included 43.6 wt% Bis-GMA, 28.2 wt% triethylene glycol dimethacrylate (TEGDMA), and 28.2 wt% hydroxyethyl methacrylate (HEMA). The photocurable system composition consisted of 4 % camphorquinone (CQ), 2.4 % ethyl 4-dimethylaminobenzoate (EDB), 3.2 % dimethylaminoethyl methacrylate (DMAEMA), and 1 % butylated hydroxytoluene (BHT). The adhesive monomer was 12 % MDP, and the filler system comprised 2 % R972 and 3 % OX50. The light curing time was set at 60 s. The adhesive exhibited optimal performance with a bonding strength of 35.9 MPa and a volumetric shrinkage of 13.3 %. According to this study, the proposed zirconia adhesive featuring a phosphate-containing acrylic ester group is a potential light-curing dental resin adhesive with a straightforward synthesis procedure, minimal volumetric shrinkage, good bonding strength, and an appropriate photocuring time.