title: One-bottle self-etching adhesives applied to dentine air-abraded using bioactive glasses containing polyacrylic acid: an in vitro microtensile bond strength and confocal microscopy study.
abstract: OBJECTIVE
  The aim of this study was to test the microtensile bond strength (μTBS) of two "simplified" self-etching adhesives bonded to air-abraded dentine using experimental bioactive glass powders containing polyacrylic acid.
  
  
  METHODS
  Sound dentine specimens were air-abraded using a pure Bioglass 45S5 (Bioglass) powder or two Bioglass powders containing different concentration of polyacrylic acid (PAA: 15 wt% or 40 wt%). The bonding procedures were accomplished by the application of two self-etching adhesives (CS3: Clearfil S3 Bond; Kuraray, Osaka, Japan or GB: G Bond; GC Ltd. Tokyo, Japan). The resin-bonded specimens were cut in beams (0.9 mm(2)) and the μTBS testing was performed after 24h or 6months of phosphate buffer solution (PBS) storage. The results were statistically analysed by three-way ANOVA and Student-Newman-Keuls test used (α=0.05). Further bonded-dentine specimens were used for the confocal microscopy interfacial characterisation and micropermeability analysis.
  
  
  RESULTS
  The CS3 adhesive system achieved higher μTBS than those attained in the specimens bonded with GB both after 24h and 6 months of PBS storage. The CLSM analysis performed after 6months of PBS storage indicated severe micropermeability within the bonded-dentine interfaces created using GB applied onto dentine air-abraded with Bioglass/PAA-15 and Bioglass/PAA-40. Conversely, CS3 exhibited no dye penetration (micropermeability) at the resin-dentine interface.
  
  
  CONCLUSIONS
  It is possible to affirm that air-abrasion procedures performed using pure Bioglass or Bioglass containing 15 wt% PAA do not interfere with the immediate bonding performance of self-etching adhesives. However, the durability of the bonded-dentine interfaces created subsequent air-abrasion procedures using bioactive glasses will depend also upon the chemical composition of the self-etch adhesive systems.
authors: Biomaterials, Biomimetics & Biophotonics, King's College London Dental Institute, King's Health Partners at Guy's Hospital, London, UK. salvatore.sauro@kcl.ac.uk
authors: Salvatore
authors: S
authors: Sauro
authors: Timothy F
authors: TF
authors: Watson
authors: Ian
authors: I
authors: Thompson
authors: Avijit
authors: A
authors: Banerjee
mesh_terms: D000180:Acrylic Resins; D020906:Air Abrasion, Dental / Q000379:methods*; D000704:Analysis of Variance; D002516:Ceramics; D001840:Dental Bonding; D045662:Dental Etching; D003799:Dental Stress Analysis; D003804:Dentin; D003806:Dentin Permeability; D017220:Dentin-Bonding Agents / Q000737:chemistry; D005898:Glass; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates; D018613:Microscopy, Confocal; D019279:Resin Cements; D018709:Statistics, Nonparametric; D013718:Tensile Strength
chemical_list: D000180:Acrylic Resins; C505694:Clearfil S3 Bond; D017220:Dentin-Bonding Agents; C498353:G-Bond; D008689:Methacrylates; D019279:Resin Cements; C425330:bioactive glass 45S5; C006903:carbopol 940