The Impact of Iodoform on the Hydration, Bioactivity and Antimicrobial Properties of White Portland Cement

Abstract

Abstract. Iodoform (CHI3) is a potential radiopacifying agent for use in Portland cement-based root-filling materials. During this study, the impact of 20 wt% iodoform on the hydration and setting of white Portland cement (WPC) was monitored by powder X-ray diffraction, 29 Si magic angle spinning nuclear magnetic resonance spectroscopy and Vicat apparatus. The presence of 20 wt% iodoform reduced the initial and final setting times of WPC from 150 to 121 min and 200 to 165 min, respectively. Iodoform had little impact on the products and extent of hydration after 7 days of curing; although, it did cause a reduction in the mean silicate chain length of the C-S-H gel (from 4.11 to 3.47 units). Both iodoform-blended and unblended cement pastes exhibited similar in vitro bioactivity, with the formation of crystalline hydroxyapatite on their surfaces within 1 day of exposure to simulated body fluid. An inhibition zone assay confirmed that WPC possesses intrinsic antimicrobial activity against S. aureus, P. aeruginosa and E. coli, which is significantly enhanced in the presence of iodoform. This study indicates that iodoform may be a suitable radiopacifying agent for Portland cementbased dental restoratives; although, further work is required to determine its long-term stability within the cement matrix.

Comparative Evaluation of Tissue Response of MTA and Portland Cement with Three Radiopacifying Agents: An Animal Study

“…18 Iodoform had no significant impact on the products and extent of hydration after 7 days. 19 Iodoform can be considered an alternative to bismuth oxide owing to the similarity in radiologic properties, tissue reaction, and anti-inflammatory properties.…”

Biocompatibility nanostructured biomaterials based on calcium aluminate

“…Although a wide range of different types of tubes are in use today -dentine [20], silicone [21], Teflon [3], polyethylene [22], polypropylene [23] -our choice were polyethylene tubes, considering their inert nature and wide application. They do not cause a tissue reaction and in controlled and effective way expose tested material to the living tissue.…”

Impact of Bi2O3 and ZrO2 Radiopacifiers on the Early Hydration and C–S–H Gel Structure of White Portland Cement

“…In order for commercial calcium silicate-based cements to comply with these standards, unreactive heavy metal oxide powders (such as Bi 2 O 3 , Zr 2 O, Ta 2 O 5 , Nb 2 O 5 , BaZrO 3 ) are typically dry-blended into the formulation to achieve acceptable radiopacity [1][2][3][4][5][6][7]. Other candidate radiopacifiers (including CHI 3 , BaSO 4 , TiF 4 , CaWO 4 , Yb 2 O 3 , YbF 3 ) have also been reported for experimental cements [10][11][12][13][14][15]; although, to date, the most commonly employed radiopacifying agents are bismuth (III) oxide (monoclinic α-Bi 2 O 3 ) and zirconium (IV) oxide (monoclinic Zr 2 O) [1][2][3][4][5][6][7].…”

“…have also been reported for experimental cements [10][11][12][13][14][15]; although, to date, the most commonly employed radiopacifying agents are bismuth (III) oxide (monoclinic α-Bi2O3) and zirconium (IV) oxide (monoclinic Zr2O) [1][2][3][4][5][6][7].…”

“…In particular, this study sought to understand the influence of these radiopacifiers on the structure of the C-S-H gel phase at a molecular level by evaluating the MCL and the extent of aluminum substitution (which have not been reported previously). Twenty wt.% (20 wt.%) radiopacifier was selected for this study, as this the most commonly used quantity of Bi 2 O 3 or ZrO 2 in both experimental and proprietary calcium silicate-based endodontic formulations and has been demonstrated to provide adequate radiopacity [1,2,6,10,16,17,20]. Cement paste samples were hydrated at 37.5 • C prior to analysis by 29 Si and 27 Al magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) at 3 and 24 h, and transmission electron microscopy (TEM) at 3 h. Initial and final setting times were determined using a Vicat apparatus and reaction kinetics were monitored by isothermal conduction calorimetry to provide a comprehensive account of the influence of these popular radiopacifying agents on the early hydration chemistry of white Portland cement.…”