title: Dental adhesives and strategies for displacement of water/solvents from collagen fibrils.
abstract: To evaluate the influence of temperature of evaporation in adhesive systems with different solvents on the apparent modulus of elasticity and mass change of macro-hybrid layers modified by proanthocyanidins (PACs).
  
  
  
  Adhesive resin beams (A) from Single Bond Plus (SB), Excite (EX) and One Step Plus (OS) were prepared after solvent evaporation at 23°C or 40°C (n=12). Macro-hybrid layers (M) (n=12) were prepared using demineralized dentin beams sectioned from extracted human third molars. The demineralized dentin specimens were infiltrated with each one of the three adhesive systems at 23°C or 40°C; with or without prior dentin treatment with PACs for 10min. The apparent modulus of elasticity (E) and mass change (Wmc, %) of adhesives beams and resin-infiltrated specimens were assessed in dry and wet conditions after immersion in water (24h, 1, 3 and 6 months). The E was statistically analyzed by Tukey-Kramer test and the Wmc, % by Kruskal Wallis, and Dunn (α=0.05).
  
  
  
  Solvent evaporation at 40°C resulted in higher E values for adhesive resin beams at all storage conditions, regardless of the adhesive system (p<0.05). Increased mass loss (3 months: -0.01%; 6 months: -0.05%) was observed in One Step resin beams (p≤0.05). In the macro-hybrid layer models the pretreatment with PACs along with solvent evaporation at 40°C increased E and decreased the Wmc, % (3 months: -2.5; 6 months: 2.75%) for adhesives evaluated over time (p<0.05). No significant differences in ratio (resin/dentin) were found for the macro-hybrid layers (p>0.05).
  
  
  
  Improved solvent evaporation at higher temperature, and increased collagen cross-linking induced by PACs, enhanced the mechanical properties resulting in highly stable macro-hybrid layers over 6 months storage.
authors.affiliation: Department of Restorative Dentistry Piracicaba Dental School, University of Campinas, 13414-903 Campinas, São Paulo, Brazil; Department of Restorative Dentistry, University of Illinois at Chicago, 60612 Chicago, IL, USA. Electronic address: larissasgarbosa@hotmail.com.
authors.forename: Larissa Sgarbosa de Araújo
authors.initials: LS
authors.lastname: Matuda
authors.affiliation: Department of Restorative Dentistry Piracicaba Dental School, University of Campinas, 13414-903 Campinas, São Paulo, Brazil.
authors.forename: Giselle Maria
authors.initials: GM
authors.lastname: Marchi
authors.affiliation: Department of Restorative Dentistry, University of Illinois at Chicago, 60612 Chicago, IL, USA.
authors.forename: Thaiane Rodrigues
authors.initials: TR
authors.lastname: Aguiar
authors.affiliation: Department of Restorative Dentistry, University of Illinois at Chicago, 60612 Chicago, IL, USA.
authors.forename: Ariene Arcas
authors.initials: AA
authors.lastname: Leme
authors.affiliation: Department of Community Dentistry Piracicaba Dental School, University of Campinas, 13414-903 Campinas, São Paulo, Brazil.
authors.forename: Gláucia M B
authors.initials: GM
authors.lastname: Ambrosano
authors.affiliation: Department of Restorative Dentistry, University of Illinois at Chicago, 60612 Chicago, IL, USA.
authors.forename: Ana Karina
authors.initials: AK
authors.lastname: Bedran-Russo
mesh_terms: D003094:Collagen; D003188:Composite Resins; D001840:Dental Bonding; D003738:Dental Cements; D003804:Dentin; D017220:Dentin-Bonding Agents; D006801:Humans; D008422:Materials Testing; D019279:Resin Cements; D012997:Solvents; D013718:Tensile Strength; D014867:Water
chemical_list: D003188:Composite Resins; D003738:Dental Cements; D017220:Dentin-Bonding Agents; D019279:Resin Cements; D012997:Solvents; D014867:Water; D003094:Collagen
keywords: Apparent modulus of elasticity; Dental adhesive; Dentin, Collagen cross-linkers; Temperature volatilization