Bioactivity of zinc-doped dental adhesives
Available online 25 December 2013
Abstract
Design of restorative materials should be focused on promoting not only adhesion but also dentine self-repair processes.
Objective
To ascertain if ZnO and ZnCl2-doped resins are materials able to induce calcium (Ca) and phosphate (P) deposition.
Methods
48
resin disks were prepared with the following materials: (1) single bond
-3M/ESPE-, (2) single bond + ZnO particles 20 wt% and (3) single
bond + ZnCl2 2 wt%. Specimens were polymerised and polished.
Bioactivity was tested through a simulated body fluid solution (SBFS)
immersion test. At time 24 h, 7 d and 21 d surfaces were analyzed by
stereomicroscope, high resolution scanning electron microscope (HRSEM),
energy-dispersive analysis (EDX), confocal laser Raman, and X-ray
diffraction (XRD) for morphological and chemical composition.
Results
Under
the stereomicroscope, crystal formations were encountered in both
zinc-doped resin adhesives after 7 d of immersion. It was, detected by
EDX, that the ZnO-doped resin produced Zn, Ca and P deposition (globular
formations were observed by HRSEM) after 7 d. Zn and P crystals were
detected by HRSEM and EDX in the experimental ZnCl2-doped
resin after 7 d and 21 d. Hopeite formation was identified by Raman on
both Zn-doped resins. Single bond did not produce mineral or crystal
precipitation.
Conclusions
ZnO-doped resin induced Ca and P deposition after SBFS immersion. On ZnCl2-doped
resin hopeite formation was detected, if this hopeite may be further
converted into apatite, after SBFS immersion, remains to be ascertained.
Comments