In vitro dentine tubule occlusion by a novel toothpaste containing calcium silicate and sodium phosphate.

Objectives: To investigate the deposition, formation of hydroxyapatite (HAP) and acid resistance of dentine surfaces following brushing with a toothpaste containing calcium silicate and sodium phosphate (CSSP) and fluoride in vitro.

Methods: Human dentine specimens were brushed with a slurry of CSSP toothpaste followed by exposure to simulated oral fluid (SOF) in two in vitro studies, with a silica-based non-occluding toothpaste as control. The surface and tubule deposits were analysed after 14 cycles with scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX), transmission electron microscopy (TEM) and selected area electron diffraction (SAED).

Dexamethasone-pDMAEMA polymeric conjugates reduce inflammatory biomarkers in human intestinal epithelial monolayers.

The mucoadhesive polymer, poly(dimethylamino)ethyl methacrylate, (pDMAEMA), was synthesised by living radical polymerisation and subsequently conjugated by quaternisation reaction to a functionalised anti-inflammatory corticosteroid dexamethasone, to separately yield two conjugates with either 9:1 or 18:1 molar ratios of dexamethasone:polymer respectively. The hypothesis was to test whether the active agent maintained in vitro bioactivity when exposed to the apical side of human intestinal epithelial monolayers, Caco-2 and mucus-covered HT29-MTX-E12 (E12). HPLC analysis indicated high conjugate purity.