Infl uence of sodium chloride content in electrolyte solution on electrochemical impedance measurements of human dentin

Abstract

Background: The aim of this study was to investigate the infl uence of sodium chloride (NaCl)
content in electrolyte solution on electrochemical impedance measurements of human dentin by
employing electrochemical impedance spectroscopy.
Materials and Methods: Dentin samples were prepared from extracted molars. Electrochemical
impedance measurements were carried out over a wide frequency range (0.01Hz-10MHz). After
measurements, samples were characterized using scanning electron microscopy.
Results: Electrochemical impedance measurements showed that the mean values of dentin
electrical resistance were 4284, 2062, 1336, 53 and 48kΩ at different NaCl contents in electrolyte
solution. One-way ANOVA test of mean values of dentin electrical resistance revealed a signifi cant
difference (P < 0.0001) as a function of NaCl content in electrolyte solution. Comparing electrical
resistance values of dentin samples at 0.05% w/v and 0.9% w/v concentrations were found to be
signifi cantly different (P < 0.05 at 95% confi dence level). Scanning electron microscopy revealed
structure of dentin sample with intertubular dentin matrix and distribution of patent dentinal tubules.
Conclusion: This in vitro study indicated, through electrochemical impedance spectroscopy
measurements, that electrical resistance of dentin was affected by the concentration of NaCl
in electrolyte solution. It is clear from the current study that NaCl concentration in electrolyte
solution has a marked infl uence on dentin electrical resistance. Therefore, this baseline data need
to be considered in any future study on dental samples.
Key Words:electric impedance, spectroscopy,dentin,electrical, resistance,Scanning Electron Microscopies,sodium chloride