Penetration of Sodium Hypochlorite Modified with Surfactants into Root Canal Dentin

Abstract The aim of this study was to evaluate the effect of concentration, exposure time and temperature of sodium hypochlorite (NaOCl) added with surfactants on its penetration into dentinal tubules. Sixty-five extracted human permanent maxillary anterior teeth with single canals were prepared by ProTaper SX hand-operated instruments. The teeth were then sectioned perpendicular to the long axis. The crowns and apical thirds of all the teeth were removed. The remaining roots were processed into 4-mm-long blocks and stained overnight in crystal violet. One hundred and thirty stained blocks were further split into halves and treated by nine different types of NaOCl-based solutions. Three solutions were added with surfactants (Hypoclean, H6, Chlor-Xtra) and the others were regular hypochlorites at increasing concentrations (1%, 2%, 4%, 5.25%, <6%, 6% NaOCl) from different brands. The dentin blocks were exposed to the solutions for 2, 5, and 20 min at 20 °C, 37 °C and 45 °C, respectively. The depth of NaOCl penetration was determined by bleaching of the stain and measured by light microscopy at 20&#61472;&#61620; and 40&#61620;. Statistical comparisons were made by using a generalized linear model with Bonferroni's post-hoc correction. The shortest penetration (81±6.6 &#956;m) was obtained after incubation in 1% NaOCl for 2 min at 20 °C; the highest penetration (376.3±3.8 &#956;m) was obtained with Chlor-Xtra for 20 min at 45 °C. Varying NaOCl concentration produced a minimal effect while temperature and exposure time had a significant direct relationship with NaOCl penetration into dentinal tubules, especially those with lowered surface tension. The exposure time and temperature of sodium hypochlorite as well as the addition of surfactants may influence the penetration depth of irrigants into dentinal tubules

Investigations of interactions in Sodium Dodecyl Sulphate - hydrophobically modified Chitosan nanoparticles

International audienc

ETUDE DES SYSTEMES POLYELECTROLYTE / TENSIOACTIF EN PHASE AQUEUSE ET A L'INTERFACE LIQUIDE / GAZ APPLICATION A L'ELABORATION DE MICRO -CAPSULES

By choosing the convenient surfactant and by adjusting the molar ratio surfactant/polyelectrolyte, it is possible to precipitate a polyelectrolyte on the surface of oil droplets by complex coacervation. The resulting insoluble surfactant/polyelectrolyte complex (SPEC) could be the membrane of the microstructured complexes and hydrophobic substances could be solubilized into the hydrophobic core. In this study, three polyelectrolyte/surfactant systems, being able to form the wall of the microcapsules, are investigated. The anionic surfactant is Sodium dodecylsulfate (SDS) and the choosen polymers are polysaccharide chitosan, hydrophobically modified chitosan and type A gelatin (protein). Physical and hydrophobic interactions (in absence of salt) between these various polyelectrolytes and the surfactant are characterized by isothermal titration calorimetry, tensiometry, conductimetry,viscosimetry, electrophoretic measurements and determination of the binding isotherms.Par coacervation complexe, en choisissant le tensioactif approprié et en jouant sur le ratio molaire tensioactif/polymère, il est possible de faire précipiter un polymère à la surface de gouttelettes d’huile : le complexe insoluble polymère/tensioactif obtenu forme alors la membrane des micro-capsules dont le coeur hydrophobe peut contenir des molécules apolaires. Cette thèse est une étude de trois systèmes polymère/tensioactif de charge opposée pouvant constituer la paroi insoluble des micro-capsules. Le tensioactif anionique utilisé est le Sodium Dodecyl Sulfate (SDS) et les polymères choisis sont un chitosane, un chitosane modifié hydrophobe et une gélatine de type A. Les interactions physiques et hydrophobes (en absence de sel) entre ces différents polymères et le tensioactif sont caractérisées par micro-calorimétrie de titration, tensiométrie, conductimétrie, viscosimétrie, mesures de mobilités électrophorétiques et détermination des isothermes de complexation du SDS aux polymères

Etude des systèmes polyélectrolytes / tensioactif en phase aqueuse et à l'interface liquide / gaz. Application à l'élaboration de micro - capsules

By choosing the convenient surfactant and by adjusting the molar ratio surfactant/polyelectrolyte, it is possible to precipitate a polyelectrolyte on the surface of oil droplets by complex coacervation. The resulting insoluble surfactant/polyelectrolyte complex (SPEC) could be the membrane of the microstructured complexes and hydrophobic substances could be solubilized into the hydrophobic core. In this study, three polyelectrolyte/surfactant systems, being able to form the wall of the microcapsules, are investigated. The anionic surfactant is Sodium dodecylsulfate (SDS) and the choosen polymers are polysaccharide chitosan, hydrophobically modified chitosan and type A gelatin (protein). Physical and hydrophobic interactions (in absence of salt) between these various polyelectrolytes and the surfactant are characterized by isothermal titration calorimetry, tensiometry, conductimetry,viscosimetry, electrophoretic measurements and determination of the binding isotherms.Par coacervation complexe, en choisissant le tensioactif approprié et en jouant sur le ratio molaire tensioactif/polymère, il est possible de faire précipiter un polymère à la surface de gouttelettes d'huile : le complexe insoluble polymère/tensioactif obtenu forme alors la membrane des micro-capsules dont le cœur hydrophobe peut contenir des molécules apolaires. Cette thèse est une étude de trois systèmes polymère/tensioactif de charge opposée pouvant constituer la paroi insoluble des micro-capsules. Le tensioactif anionique utilisé est le Sodium Dodecyl Sulfate (SDS) et les polymères choisis sont un chitosane, un chitosane modifié hydrophobe et une gélatine de type A. Les interactions physiques et hydrophobes (en absence de sel) entre ces différents polymères et le tensioactif sont caractérisées par micro-calorimétrie de titration, tensiométrie, conductimétrie, viscosimétrie, mesures de mobilités électrophorétiques et détermination des isothermes de complexation du SDS aux polymères

Étude des systèmes polyélectrolyte-tensioactif en phase aqueuse et à l'interface liquide-gaz (application à l'élaboration de micro-capsules)

MONTPELLIER-BU Sciences (341722106) / SudocSudocFranceF

Studies of the association of chitosan and alkylated chitosan with oppositely charged sodium dodecyl sulfate

International audienc

Study of the complex formation between sodium dodecyl sulfate and hydrophobically modified chitosan

International audienc

Study of the complex formation between sodium dodecyl sulfate and chitosan

International audienc

Study of the complex formation between sodium dodecyl sulphate and gelatin

International audienc