Etude semi-quantitative in vitro du mordançage de l’émail humain: observations au microscope électronique à balayage

Authors

  • J Rodde

Keywords:

etching, human enamel, lactic acid, citric acid, hydrochloric acid, phosphoric acid, SEM.

Abstract

The efficiency of etching using lactic, citric, hydrochloric and phophoric acids has been studied with the scanning electron microscope on 557 human enamel surfaces. A semi-quantitative assessment has been performed with reference to Silverstone et al.’s classification (1975) as regards the demineralization stages of enamel prisms and to Sheykholeslam and Buonocuore’s 6 points scale as regards the etching degrees.

Lactic and citric acids proved ineffective. Hydrochloric and phosphoric acids were efficient between 20 and 50% concentrations. A 1 minute etching seems optimal. A long-continued etching induces crackling of the surface enamel layer into patches which do not stick properly to the underlying enamel. Only the removal of the hypermineralized surface layer (using a diamond wheel) allows to obtain microporosities evenly distributed all over the sample surface. A mechanical teatment of enamel surfaces prior to etching is necessary especially when temporary teeth or «mature» (between 5 and 50) or «aged» (over 50) teeth are concerned.

Published

2020-04-17

Issue

Section

Original Research Articles