title: Zn-doped etch-and-rinse model dentin adhesives: Dentin bond integrity, biocompatibility, and properties.
abstract: This study assessed a 6 month resin/dentin bond's durability and cytotoxic effect of Zn-doped model dentin adhesives. The mechanical and physicochemical properties were also tested.
  
  
  
  A model etch-and-rinse single-bottle adhesive was formulated (55wt.% Bis-GMA, 45wt.% HEMA, 0.5wt.% CQ, 0.5wt.% DMAEMA) and Zinc methacrylate (Zn-Mt) or ZnO nanoparticles (ZnOn) were added to the model's adhesive, resulting in three groups: Group Control (control model adhesive); Group Zn-Mt (1wt.% Zn-Mt incorporated to adhesive) and Group ZnOn (1wt.% ZnOn incorporated to adhesive). The microtensile bond strength (mTBS) was assessed after 24h or 6 months in water storage. Mechanical properties (diametral tensile strength/DTS, flexural strength/FS, flexural modulus/FM, resilience modulus/RM, and compressive strength/CS) and physicochemical properties (polymerization shrinkage/PS, contact angle/CA, water sorption/WS, and water solubility/WS) were also tested. Cytotoxicity was evaluated with SRB biochemical assay.
  
  
  
  No significant difference in the DTS, FS, FM, CS, CA, WS, and WS were found when 1% of ZnOn or Zn-Mt was added to the model dentin adhesive. Group Zn-Mt decreased the RM of adhesive. Groups Zn-Mt and ZnOn decreased the PS of adhesives. Group ZnOn reduced the cytotoxicity of adhesive. Group ZnOn preserved mTBS after 6 months storage without degradation areas as seen by SEM analysis.
  
  
  
  The 1wt.% ZnOn may preserve the integrity of the hybrid layer and may reduce cytotoxicity and polymerization shrinkage of model dentin adhesive. The addition of Zn-Mt to the adhesive had no beneficial effects.
authors.affiliation: São José dos Campos School of Dentistry, Department of Restorative Dentistry, UNESP - Univ Estadual Paulista, São José dos Campos, SP, Brazil.
authors.forename: Daphne Câmara
authors.initials: DC
authors.lastname: Barcellos
authors.affiliation: Clinical Research Academic Group, Institute of Science and Technology, UNESP - Univ Estadual Paulista, São José dos Campos, SP, Brazil.
authors.forename: Beatriz Maria
authors.initials: BM
authors.lastname: Fonseca
authors.affiliation: Department of Restorative Dentistry, UNESP - Univ Estadual Paulista, São José dos Campos, SP, Brazil.
authors.forename: César Rogério
authors.initials: CR
authors.lastname: Pucci
authors.affiliation: Department of Cariology, Restorative Sciences and Endodontics, School of Dentistry - University of Michigan, USA.
authors.forename: Bruno das Neves
authors.initials: Bd
authors.lastname: Cavalcanti
authors.affiliation: Electrical System, Embraer Defense and Security, Brazil.
authors.forename: Erasmo De Souza
authors.initials: Ede S
authors.lastname: Persici
authors.affiliation: Department of Restorative Dentistry, UNESP - Univ Estadual Paulista, São José dos Campos, SP, Brazil. Electronic address: sergio@fosjc.unesp.br.
authors.forename: Sérgio Eduardo de Paiva
authors.initials: SE
authors.lastname: Gonçalves
mesh_terms: D000269:Adhesives; D001840:Dental Bonding; D003738:Dental Cements; D003804:Dentin; D017220:Dentin-Bonding Agents; D008422:Materials Testing; D019279:Resin Cements; D013499:Surface Properties; D013718:Tensile Strength; D013997:Time Factors; D015032:Zinc
chemical_list: D000269:Adhesives; D003738:Dental Cements; D017220:Dentin-Bonding Agents; D019279:Resin Cements; D015032:Zinc
keywords: Collagen; Dental adhesive; Dentin-bond agents; Matrix metalloproteinase inhibitors; Methacrylates; Zinc oxide