Defying ageing: An expectation for dentine bonding with universal adhesives?

• Published in: Journal of dentistry Vol. 45; pp. 43 - 52
• Main Authors: Zhang, Zheng-yi, Tian, Fu-cong, Niu, Li-na, Ochala, Kirsten, Chen, Chen, Fu, Bai-ping, Wang, Xiao-yan, Pashley, David H, Tay, Franklin R
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.02.2016; Elsevier Limited
• Subjects: Acid Etching, Dental - methods; Acids; Adhesive bonding; Adhesives; Aging; Bisphenol A-Glycidyl Methacrylate - chemistry; Bond strength; Bonding; Bonding strength; Collagen - metabolism; Collagens; Composite Resins - chemistry; Degradation; Dental Bonding; Dental Cements - chemistry; Dental Enamel - ultrastructure; Dentin - diagnostic imaging; Dentin - ultrastructure; Dentin-Bonding Agents - chemistry; Dentin-Bonding Agents - classification; Dentistry; Etching; Ethanol; Humans; Light; Materials Testing; Methacrylates - chemistry; Nanoparticles; Phosphoric Acids; Polymethacrylic Acids - chemistry; Resin Cements - chemistry; Solvents; Stress, Mechanical; Surface Properties; Teeth; Tensile Strength; Water - chemistry
• ISSN: 0300-5712; 1879-176X
• DOI: 10.1016/j.jdent.2015.11.008

Abstract Objectives The present study evaluated the long-term dentine bonding effectiveness of five universal adhesives in etch-and-rinse or self-etch mode after 12 months of water-ageing. Methods The adhesives evaluated included All-Bond Universal, Clearfil Universal Bond, Futurabond U Prime&Bond Elect and Scotchbond Universal. Microtensile bond strength and transmission electron microscopy of the resin-dentine interfaces created in human coronal dentine were examined after 24 h or 12 months. Results Microtensile bond strength were significantly affected by bonding strategy (etch-and-rinse vs self-etch) and ageing (24 h vs 12 months). All subgroups showed significantly decreased bond strength after ageing except for Prime&Bond Elect and Scotchbond Universal used in self-etch mode. All five adhesives employed in etch-and-rinse mode exhibited ultrastructural features characteristic of collagen degradation and resin hydrolysis. A previously-unobserved inside-out collagen degradation pattern was identified in hybrid layers created by 10-MDP containing adhesives (All-Bond Universal, Scotchbond Universal and Clearfil Universal Bond) in the etch-and-rinse mode, producing partially degraded collagen fibrils with intact periphery and a hollow core. In the self-etch mode, all adhesives except for Prime&Bond Elect exhibited degradation of the collagen fibrils along the thin hybrid layers. The three 10-MDP containing universal adhesives did not protect surface collagen fibrils from degradation when bonding was performed in the self-etch mode. Conclusions Despite the adjunctive conclusion that bonds created by universal adhesives in the self-etch bonding mode are more resistant to decline in bond strength when compared with those bonds created using the etch-and-rinse mode, bonds created by universal adhesives are generally incapable of defying ageing.