Abstract:
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Gandolfi MG, Taddei P, Siboni F, Modena E, Ginebra
MP, Prati C. Fluoride-containing nanoporous calcium-silicate
MTA cements for endodontics and oral surgery: early fluorapatite
formation in a phosphate-containing solution. International
Endodontic Journal, 44, 938–949, 2011.
Aim To test the chemical–physical properties and
apatite-forming ability of experimental fluoride-doped
calcium silicate cements designed to create novel
bioactive materials for use in endodontics and oral
surgery.
Methodology A thermally treated calcium silicate
cement (wTC) containing CaCl2 5%wt was modified by
adding NaF 1%wt (FTC) or 10%wt (F10TC). Cements
were analysed by environmental scanning electron
microscopy with energy-dispersive X-ray analysis, IR
and micro-Raman spectroscopy in wet conditions
immediately after preparation or after ageing in a
phosphate-containing solution (Dulbecco’s phosphatebuffered
saline). Calcium and fluoride release and pH of
the storage solution were measured. The results
obtained were analysed statistically (Tukey’s HSD test
and two-way anova).
Results The formation of calcium phosphate precipitates
(spherulites) was observed on the surface of
24 h-aged cements and the formation of a thick
bone-like B-type carbonated apatite layer (biocoating)
on 28 day-aged cements. The rate of apatite formation
was FTC > F10TC > wTC. Fluorapatite was
detected on FTC and F10TC after 1 day of ageing,
with a higher fluoride content on F10TC. All the
cements released calcium ions. At 5 and 24 h, the
wTC had the significantly highest calcium release
(P < 0.001) that decreased significantly over the
storage time. At 3–28 days, FTC and F10TC had
significantly higher calcium release than wTC
(P < 0.05). The F10TC had the significantly highest
fluoride release at all times (P < 0.01) that decreased
significantly over storage time. No significant differences
were observed between FTC and wTC. All the
cements had a strong alkalinizing activity (OH)
release) that remained after 28 days of storage.
Conclusions The addition of sodium fluoride accelerated
apatite formation on calcium silicate cements.
Fluoride-doped calcium silicate cements had higher
bioactivity and earlier formation of fluorapatite. Sodium
fluoride may be introduced in the formulation of
mineral trioxide aggregate cements to enhance their
biological behaviour. F-doped calcium silicate cements
are promising bone cements for clinical endodontic use. |