Incidence des eaux embouteillées sur la dissolution de l’hydroxyapatite dentaire. Influence de différents paramètres

Abstract

The present study focused on two main aspects, the first was to characterize the Algerian bottled waters, natural mineral and spring waters through an experimental, graphical and multivariate statistical analysis of physicochemical and bacteriological quality parameters. Emphasis was on the presence of fluorides and the conformity of labeling. These investigations have led to classify the waters in terms of mineralization, chemical facies and fluorine intake. The second objective of this work was to study the effect of different water brands on the dissolution of hydroxyapatite CaHAp, the main chemical constituent of dental enamel. To do this, in vitro model was adopted to follow the dissolution kinetics of CaHAp under conditions simulated to the buccal cavity in different media, namely: reference medium, synthetic and in presence of bottled waters. The competition of coexisting anions such as chlorides, hydrogencarbonates, sulfates with F- has been demonstrated and has considerably affected the dissolution process, consequently the inhibitory effect of bottled waters on the process is closely related to the overall water quality and not only to their fluoride content. The results allowed us to identify water brands of particular interest for oral health. A microfluidic approach has been developed to study the effects of pH variation and nature of bacteria. The dissolution kinetics of CaHAp were carried out in a PDMS microfluidic channel at different pH (4 to 7.00) using a white light optical microscope in presence of selected bacteria: "Streptococcus salivarius" with and without glucose. The obtained results confirmed the formation of bacterial biofilm on the CaHAp surface and the pH of 4.32 which represents significantly the dissolution phenomenon of CaHAp.