Efficacy and micro-characterization of pathophysiological events on caries-affected dentin treated with glass-ionomer cements
Metadatos
Mostrar el registro completo del ítemAutor
Toledano Pérez, Manuel; Sánchez Aguilera, Fátima; Osorio Ruiz, María Estrella; Cabello Malagón, Inmaculada; Toledano Osorio, Manuel; Osorio Ruiz, RaquelEditorial
Elsevier
Materia
Glass ionomer cements Remineralization Interface Load cycling Resin modified GICs Sound dentin Caries-affected dentin
Fecha
2016-09Referencia bibliográfica
Toledano Pérez, M.; et al. Efficacy and micro-characterization of pathophysiological events on caries-affected dentin treated with glass-ionomer cements. International Journal of Adhesion and Adhesives: online (2016). [http://hdl.handle.net/10481/41561]
Patrocinador
Project MAT2014-52036-P supported by the Ministery of Economy and Competitiveness (MINECO) and European Regional Development Fund (FEDER).Resumen
The aim of this study was to evaluate if mechanical cycling influences bioactivity and
bond strength at the glass-ionomer cement-dentin interface, after load cycling.
Microtensile bond strength (MTBS) was assessed with Ketac-Bond (conventional glass
ionomer/GIC) or Vitrebond Plus (resin-modified/RMGIC), in sound dentin or in cariesaffected
dentin (CAD). Debonded dentin surfaces were studied by field emission
scanning electron microscopy (FESEM), and remineralization was evaluated through
nanohardness (Hi) and Young’s modulus (Ei), Raman spectroscopy, and Masson's
trichrome staining technique. Load cycling did not affect MTBS, except when Ketac-
Bond was applied on sound dentin, which attained 100% pretesting failures. Minerals
precipitated in porous platforms. GIC promoted total occlusion of tubules, and RMGIC
originated empty or partial occluded tubules. In sound dentin, load cycling produced an
increase of the relative presence of crystalline minerals after using Ketac-Bond
(Phosphate peak, from 18.04 up to 81.29 cm-1 at hybrid layer, and from 19.28 up to
108.48 cm-1 at the bottom of the hybrid layer; Carbonate peak, from 8.06 up to 15.43
cm-1 at the hybrid layer, and from 7.22 up to 19.07 cm-1 at the bottom of the hybrid
layer). Vitrebond Plus, in sound dentin, attained opposite outcomes. In CAD treated
with Ketac- Bond, the highest Hi (1.11 GPa) and Ei (32.91 GPa) values were obtained
at the hybrid layer after load cycling. This GIC showed increased and immature mineral
components (an average of 25.82 up to 30.55 cm-1), higher frequencies of crosslinking
(considering the pyridinium ring at hybrid layer, from 4.1 up to 6.86 cm-1; at bottom of
the hybrid layer, from 7.55 up to 8.58 cm-1) and worst collagen quality (considering the
ratio amide I/AGEs-pentosidine at the hybrid layer, from 0.89 up to 0.69 cm-1; at the
bottom of the hybrid layer, from 1.39 up to 1.29 cm-1) after load cycling, at the interface
of the CAD samples. Both Hi and Ei of CAD treated with RMGIC were not affected
4
after load cycling, though phosphates, carbonates and crystallinity increased. The
organic components showed a dissimilar crosslinking and an improvement of the nature
of collagen. Trichrome staining showed lower signs of demineralization or exposed
proteins after mechanical loading, though Vitrebond Plus exhibited a slight increment in
red intensity at the interface. The null hypothesis to be tested is that bond strength,
chemical bonding and mechanical performance of the tested ionomer-based cements
would not be influenced by the application of load cycling on restorations of sound and
caries-affected dentin substrates.