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Effects of dual antibacterial agents MDPB and nano-silver in primer on microcosm biofilm, cytotoxicity and dentin bond properties



Ke Zhang, Lei Cheng, Satoshi Imazato, Joseph M. Antonucci, Nancy Lin, Sheng Lin-Gibson, Yuxing Bai, Hockin H. Xu


Objectives: Secondary caries at restoration margins is the main reason for restoration failure. Antibacterial bonding agents are promising to inhibit biofilm acids at the tooth-restoration interfaces. The objective of this study was to investigate the effects of the primer containing dual antibacterial agents, namely, 12-methacryloyloxydodecylpyridinium bromide (MDPB) and nanoparticles of silver (NAg), on dentin bond strength, dental plaque microcosm biofilm response, and fibroblast cytotoxicity for the first time. Methods: Scotchbond Multi-Purpose (SBMP) was used. Four primers were tested: SBMP primer P, P + 5% MDPB, P + 0.05% NAg, and P + 5% MDPB + 0.05% NAg. Dentin shear bond strengths were measured. A microcosm biofilm model with mixed saliva from 10 donors as inoculum was used to investigate biofilm metabolic activity, colony-forming units (CFU), and lactic acid production. Human fibroblast cytotoxicity of the primers was tested. Results: Incorporating MDPB and NAg into primer did not reduce dentin bond strength compared to control(p > 0.1). SEM revealed well-bonded adhesive-dentin interfaces with numerous resin tags for all groups. MDPB or NAg each greatly reduced biofilm viability and acid production, compared to control. Dual agents MDPB+NAg had a much stronger effect than using each agent alone (p < 0.05), increasing the inhibition zone size and reducing the metabolic activity, CFU and lactic acid by an order of magnitude, compared to control. There was no difference in cytotoxicity between control and antibacterial primers (p > 0.1). Conclusions: The use of dual agents MDPB and NAg in primer yielded potent antibacterial properties for the first time, and is promising to combat residual bacteria in tooth cavity and invading bacteria at the margins. The combination of MDPB and NAg may have wide applicability to other adhesive systems, composites and cements to inhibit biofilm and caries.
Journal of Dentistry


antibacterial primer, caries inhibition, dentin bond strength, human saliva microcosm biofilm, MDPB, silver nanoparticles


Zhang, K. , Cheng, L. , Imazato, S. , Antonucci, J. , Lin, N. , Lin-Gibson, S. , Bai, Y. and Xu, H. (2013), Effects of dual antibacterial agents MDPB and nano-silver in primer on microcosm biofilm, cytotoxicity and dentin bond properties, Journal of Dentistry, [online], (Accessed June 28, 2022)
Created January 31, 2013, Updated October 12, 2021