Design of restorative materials should be focused on promoting not only adhesion but also dentine self-repair processes

October 5, 2018

Title

Design of restorative materials should be focused on promoting not only adhesion but also dentine self-repair processes

Author

Raquel Osorio, Inmaculada Cabello, Manuel Toledano

Year

2014

Journal

Journal of Dentistry

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.

Clinical significance
Bonding with ZnO-doped resin may facilitate incorporation of Ca and P at the interfacial bonding zone.

Instrument

NRS-5100

Keywords

Bioactivity, Zinc, Calcium phosphate, Resin