Effects of chlorhexidine-containing adhesives on the durability of resin–dentine interfaces

• Published in: Journal of dentistry 2014-01, Vol.42 (1), p.39-47
• Main Authors: Stanislawczuk, Rodrigo, Pereira, Fabiane, Muñoz, Miguel Angel, Luque, Issis, Farago, Paulo Vitor, Reis, Alessandra, Loguercio, Alessandro D
• Format: Article
• Language: English
• Subjects: Accumulation; Acid Etching, Dental - methods; Adhesives; Adhesives systems; Adolescent; Adult; Aqueous solutions; Bond strength; Bonding; Bonding strength; Chlorhexidine; Chlorhexidine - chemistry; Collagen; Composite Resins - chemistry; Dental Bonding; Dental Leakage - classification; Dental Materials - chemistry; Dentin - ultrastructure; Dentin-Bonding Agents - chemistry; Dentistry; Direct current; Durability; Enamel; Etching; Humans; Long-term; Materials Testing; Mechanical properties; Methacrylates - chemistry; Microscopy, Electron, Scanning; Microtensile bond strength; Nanoleakege; Nanostructure; Polymerization; Polyurethanes - chemistry; Reduction; Solubility; Stress, Mechanical; Studies; Surface Properties; Surface-Active Agents - chemistry; Teeth; Tensile Strength; Time Factors; Water - chemistry; Young Adult
• ISSN: 0300-5712; 1879-176X
• DOI: 10.1016/j.jdent.2013.11.002

Abstract Objectives This study evaluated the effect of addition of diacetate CHX in different concentrations into two simplified etch-and-rinse (ER) adhesive systems (XP Bond [XP] and Ambar {AM}) on the ultimate tensile strength (UTS), degree of conversion (DC), 60-day cumulative water sorption (WS), solubility (SO) and CHX release (CR) as well as the immediate (IM) and 1-year (1Y) resin–dentine bond strength (μTBS) and nanoleakage (NL). Methods Ten experimental adhesive systems were formulated according to the addition of CHX diacetate (0 [control], 0.01, 0.05, 0.1 and 0.2%) in the two ER. For UTS and DC, specimens were constructed and tested after 24 h. For WS, SO and CR, after specimens build-up, they were stored in water and the properties measured after 60 days. The occlusal enamel of fifty molars was removed and the adhesives were applied in dentine surface after 37% phosphoric acid etching. After composite resin build-ups, specimens were longitudinally sectioned to obtain resin–dentine bonded sticks (0.8 mm2 ). Specimens were tested in tension at 0.5 mm/min in the IM or 1Y. For NL, 2 bonded sticks from each tooth were prepared and analyzed under SEM. The data were submitted to appropriate statistical analysis (α = 0.05). Results The addition of CHX did not influence UTS, DC, WS and SO ( p < 0.05). Higher CR was observed in adhesives with higher concentration of CHX ( p < 0.05). After 1Y, significant reductions of μTBS and increases of NL were observed in the control groups ( p < 0.05). Reductions of μTBS and increase of NL over time were not observed (AM) for CHX-containing adhesives or it was less pronounced than the control (XP) regardless of the CHX concentration. Conclusions The addition of CHX diacetate in concentrations until 0.2% in the simplified ER adhesive systems may be an alternative to increase the long-term stability of resin–dentine interfaces, without jeopardizing the adhesives’ mechanical properties evaluated.