Characterization of calcium oxide in root perforation sealer materials

Abstract

Root perforation represents an undesirable complication that may lead to an unfavorable prognosis. The aims of this study were to characterize and to compare the presence of calcium oxide (CaO) on the chemical composition of materials used for root perforation therapy: gray and white mineral trioxide aggregate (MTA) and Portland cement (PC), gray MTA+5%CaO and gray MTA+10%CaO. The last two materials were analyzed to evaluate the increase of CaO in the final sample. CaO alone was used as a standard. Eighteen polyethylene tubes with an internal diameter of 3 mm and 3 mm in length were prepared, filled and then transferred to a chamber with 95% relative humidity and a temperature of 37ºC. The chemical compounds (particularly CaO) and the main components were analyzed by energy-dispersive X-ray microanalysis (EDX). EDX revealed the following concentrations of CaO: gray MTA: 59.28%, white MTA: 63.09%; PC: 72.51%; gray MTA+5%CaO: 63.48% and gray MTA+10%CaO: 67.55%. The tested materials presented different concentrations of CaO. Even with an increase of 5 and 10% CaO in gray MTA, the CaO levels found in the MTA samples were lower than those found in PC.

Determination of trace elements in kidneys, livers and brains of rats with sealer implants by ICP-MS

“…The chemical effect of root canal sealers used adjacent to periapical tissues is a predictor of their physical, chemical and biological properties [19,20]. In the case of a sealer that has extended beyond the root canal space, corrosion of the sealer surface causes in vivo release of various elements over time.…”

Ultrasonically Activated Irrigation to Remove Calcium Hydroxide from Apical Third of Human Root Canal System: A Systematic Review of In Vitro Studies

“…Scanning electron microscopic studies were also excluded even if they assessed the apical third. It is impossible to distinguish Ca(OH) 2 remnants from the smear layer or dentin debris because energydispersive X-ray spectroscopy analysis shows Ca ++ in both cases (36)(37)(38). For these reasons, 3 studies were excluded even though they assessed the apical third of the root canal (39)(40)(41).…”

Presence of Metallic Microfragments on Dentinal Walls and Instrument Defects following Root Canal Preparation

“…The EDX allows to determine the composition and distribution of chemical elements in different materials and has been increasingly used in endodontics. 12,14,15,23 In our sample, the presence of chemical elements was relatively low. One explanation for this could be that only the distal canals of mandibular molars were analyzed, and these canals are usually wide and proximally Graph 1: Chemical characterization of metallic fragments found on the surface of the dentinal walls of root canals in the K-FlexoFile groups 24 Previous studies 25,26 had already reported that endodontic instruments usually do not touch all dentinal walls of wide, flattened canals during the shaping process.…”

“…More specifically, EDX allows to identify and precisely measure the concentration of the chemical elements present in different materials and types of samples. [12][13][14] Most stainless steel files present high concentrations of iron, chrome, and nickel in their chemical composition. 13 The NiTi instruments, in turn, are comprised of approximately 54.2-57% of nickel and 44-45% of titanium.…”