Zn-doped etch-and-rinse model dentin adhesives: Dentin bond integrity, biocompatibility, and properties

• Autor(a) principal: Barcellos, Daphne Câmara [UNESP]
• Data de Publicação: 2016
• Outros Autores: Fonseca, Beatriz Maria [UNESP], Pucci, César Rogério [UNESP], Cavalcanti, Bruno Das Neves, Persici, Erasmo De Souza, De Paiva Gonçalves, Sérgio Eduardo [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1016/j.dental.2016.04.003; http://hdl.handle.net/11449/173676
• topic: Collagen; Dental adhesive; Dentin-bond agents; Matrix metalloproteinase inhibitors; Methacrylates; Zinc oxide

Objective 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. Methods A model etch-and-rinse single-bottle adhesive was formulated (55 wt.% Bis-GMA, 45 wt.% HEMA, 0.5 wt.% CQ, 0.5 wt.% 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 (1 wt.% Zn-Mt incorporated to adhesive) and Group ZnOn (1 wt.% ZnOn incorporated to adhesive). The microtensile bond strength (mTBS) was assessed after 24 h 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. Results 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. Significance The 1 wt.% 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.