BACKGROUND One ideal property of a root-end filling material is its apical sealing ability. The aim of this in vitro study was to assess bacterial and dye microleakage of white and gray mineral trioxide aggregate (WMTA and GMTA), Portland cement and calcium-enriched mixture (CEM) cement used as root-end filling material, and to assess the agreement between these two test methods. MATERIALS AN...

In the cellulose industry the Kraft process is widely used to produce cellulose. This process generates huge volumes of inorganic solid wastes, including the grits waste. In Brazil, the final disposal of this solid waste is of high economical and environmental interest. The present work assesses the influence of the addition of grits waste on the densification behavior of soil-cement bricks. Th...

Stephen S. Szoke, P.E., LEED/AP, FACI Director, Codes and Standards Portland Cement Association 5420 Old Orchard Road, Skokie, IL 60077 +1-847-972-9078 [email protected] Stephen V. Skalko, P.E. Manager, Regional Code Services Portland Cement Association 128 Summerfield Drive, Macon, GA 31210 +1-478-477-5028 [email protected] A paper presented at the April 23-25, 2012 The Infrastructure Security...

Estimation of water soluble hexavalent chromium and total chromium has been devised. For the complete extraction of water soluble hexavalent chromium, leaching period of five days is done. It was ascertained that complete extraction was achieved in five days; the total chromium determination in these samples was done by fusing sample with sodium carbonate up to 1050 C in muffle furnace. Chromiu...

In this paper, two types of sustainable cementitious composites, geopolymer and magnesium phosphate cement, are introduced. The geopolymer is a type of amorphous alumino-silicate products and magnesium cement is MgO based cementitious material. Geopolymer can be synthesized by polycondensation reaction of geopolymeric precursor, and alkali polysilicates. The MgO cement can be obtained by proper...

MODELING OF HYDRATION KINETICS AND SHRINKAGE OF PORTLAND CEMENT PASTE

OBJECTIVE This study compared the chemical constitution, radiopacity, and biocompatibility of Portland cement containing bismuth oxide (experimental cement) with those of Portland cement and mineral trioxide aggregate (MTA). STUDY DESIGN The chemical constitution of materials was determined by scanning electron microscopy and energy-dispersive X-ray analysis. The radiopacity of the materials ...

Cement manufacture has undergone extensive change in its attempts to rise to the successive challenges posed by society. The hydration of Portland cement is a complex phenomenon that depends on both reagent characteristics and reaction conditions. It is a well-known fact that the curing temperature plays an important role on the hydration kinetics. The present study is the first to be undertake...

Physicochemical properties of pozzolan Portland cement were compared to ProRoot MTA and MTA BIO. To test the pH, the samples were immersed in distilled water for different periods of time. After the pH analysis, the sample was retained in the plastic recipient, and the electrical conductivity of the solution was measured. The solubility and radiopacity properties were evaluated according to spe...