title: Bonding of universal adhesives to dentine--Old wine in new bottles?
abstract: OBJECTIVE
  Multi-mode universal adhesives offer clinicians the choice of using the etch-and-rinse technique, selective enamel etch technique or self-etch technique to bond to tooth substrates. The present study examined the short-term in vitro performance of five universal adhesives bonded to human coronal dentine.
  
  
  METHODS
  Two hundred non-carious human third molars were assigned to five groups based on the type of the universal adhesives (Prime&Bond Elect, Scotchbond Universal, All-Bond Universal, Clearfil Universal Bond and Futurabond U). Two bonding modes (etch-and-rinse and self-etch) were employed for each adhesive group. Bonded specimens were stored in deionized water for 24h or underwent a 10,000-cycle thermocycling ageing process prior to testing (N=10). Microtensile bond testing (μTBS), transmission electron microscopy (TEM) of resin-dentine interfaces in non-thermocycled specimens and scanning electron microscopy (SEM) of tracer-infused water-rich zones within hybrid layers of thermocycled specimens were performed.
  
  
  RESULTS
  Both adhesive type and testing condition (with/without thermocycling) have significant influences on μTBS. The use of each adhesive in either the etch-and-rinse or self-etch application mode did not result in significantly different μTBS to dentine. Hybrid layers created by these adhesives in the etch-and-rinse bonding mode and self-etch bonding mode were ∼5μm and ≤0.5μm thick respectively. Tracer-infused regions could be identified within the resin-dentine interface from all the specimens prepared.
  
  
  CONCLUSIONS
  The increase in versatility of universal adhesives is not accompanied by technological advances for overcoming the challenges associated with previous generations of adhesives. Therapeutic adhesives with bio-protective and bio-promoting effects are still lacking in commercialized adhesives.
  
  
  CONCLUSIONS
  Universal adhesives represent manufacturers' attempt to introduce versatility in product design via adaptation of a single-bottle self-etch adhesive for other application modes without compromising its bonding effectiveness.
authors: Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University; Department of Operative Dentistry & Endodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, Jiangsu, China.
authors: C
authors: C
authors: Chen
authors: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, Shaanxi, China.
authors: L-N
authors: LN
authors: Niu
authors: Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University; Department of Prosthodontics, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, Jiangsu, China.
authors: H
authors: H
authors: Xie
authors: Department of Prosthodontics, School & Hospital of Stomatology, Zhejiang University, Hangzhou, Zhejiang, China.
authors: Z-Y
authors: ZY
authors: Zhang
authors: The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory for Oral Biomedical Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China.
authors: L-Q
authors: LQ
authors: Zhou
authors: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, Shaanxi, China.
authors: K
authors: K
authors: Jiao
authors: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, Shaanxi, China. Electronic address: jhchen@fmmu.edu.cn.
authors: J-H
authors: JH
authors: Chen
authors: Department of Oral Biology, Georgia Regents University, Augusta, GA, USA.
authors: D H
authors: DH
authors: Pashley
authors: Department of Endodontics, Georgia Regents University, Augusta, GA, USA. Electronic address: ftay@gru.edu.
authors: F R
authors: FR
authors: Tay
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000269:Adhesives / Q000737:chemistry*; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding / Q000379:methods*; D003743:Dental Enamel; D003764:Dental Materials / Q000737:chemistry; D003804:Dentin / Q000737:chemistry* / Q000648:ultrastructure; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011897:Random Allocation; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties; D013718:Tensile Strength; D017001:Tooth Demineralization
chemical_list: D000269:Adhesives; C074864:All-Bond system; D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D008689:Methacrylates; D011109:Polymethacrylic Acids; C103500:Prime & Bond; D019279:Resin Cements; D017438:Bisphenol A-Glycidyl Methacrylate; C041330:Scotchbond
keywords: Bond strength; Dentine; Nanoleakage; Universal adhesives