Microparticulated and nanoparticulated zirconium oxide added to calcium silicate cement: Evaluation of physicochemical and biological properties

Abstract

The physicochemical and biological properties of calcium silicate-based cement (CS) associated to microparticulated (micro) or nanoparticulated (nano) zirconium oxide (ZrO 2 ) were compared with CS and bismuth oxide (BO) with CS. The pH, release of calcium ions, radiopacity, setting time, and compression strength of the materials were evaluated. The tissue reaction promoted by these materials in the subcutaneous was also investigated by morphological, immunohistochemical, and quantitative analyses. For this purpose, polyethylene tubes filled with materials were implanted into rat subcutaneous. After 7, 15, 30, and 60 days, the tubes surrounded by capsules were fixed and embedded in paraffin. In the H&E-stained sections, the number of inflammatory cells (ICs) in the capsule was obtained. Moreover, detection of interleukin-6 (IL-6) by immunohistochemistry and number of IL-6 immunolabeled cells were carried out. von Kossa method was also performed. The differences among the groups were subjected to Tukey test (p 0.05). The solutions containing the materials presented an alkaline pH and released calcium ions. The addition of radiopacifiers increased setting time and radiopacity of CS. A higher compressive strength in the CS 1 ZrO 2 (micro and nano) was found compared with CS 1 BO. The number of IC and IL-6 positive cells in the materials with ZrO 2 was significantly reduced in comparison with CS 1 BO. von Kossa-positive structures were observed adjacent to implanted materials. The ZrO 2 associated to the CS provides satisfactory physicochemical properties and better biological response than BO. Thus, ZrO 2 may be a good alternative for use as radiopacifying agent in substitution to BO.

Pulp tissue response to Portland cement associated with different radio pacifying agents on pulpotomy of human primary molars

“…Silva et al . () revealed better biological response to zirconium oxide than bismuth oxide added to PC in rat connective tissue. Other investigation in animals compared the effects of PC with iodoform and zirconium oxide, and morphological analysis revealed that groups including radio pacifying agents showed lower inflammation than pure PC group (Lourenço‐Neto et al ., ).…”

“…Iodoform seems to be harmless to connective tissue and it is widely available to clinicians (de Morais et al, 2006;Bortoluzzi et al, 2009). Another tested radiopacifier, zirconium oxide does not affect tissue integrity (Lourenço-Neto et al, 2014;Silva et al, 2014), and furthermore, preserves PC properties (Bortoluzzi et al, 2009;Húngaro-Duarte et al, 2009;Camilleri et al, 2011;Cutajar et al, 2011;Guerreiro-Tanomaru et al, 2012;Weckwerth et al, 2012).…”

“…To judge pulp capping materials effectiveness, histopathological tissue evaluation might be performed in addition to clinical trials, because toxic constituents of the cements may induce irritation or even tissue degeneration (Coutinho-Filho et al, 2008;Lourenço-Neto et al, 2014). In vivo evaluation of tissue response to PC has been mainly performed in rats, showing mild to absent inflammatory cells infiltration and dense connective tissue, indicating repair process (de Morais et al, 2006;Shahi et al, 2010;Marques et al, 2013;Koçak et al, 2014;Marciano et al, 2014b;Silva et al, 2014). Several studies state that inflammatory tissue response to PC decreases over time (Menezes et al, 2004;Shahi et al, 2010;Kurita et al, 2013;Marques et al, 2013;Koçak et al, 2014;Marciano et al, 2014b).…”

Effect of Zirconium Oxide and Zinc Oxide Nanoparticles on Physicochemical Properties and Antibiofilm Activity of a Calcium Silicate-Based Material

“…Six samples, with 10 mm diameter by 1.0 mm thickness, of each group were subjected to the radiopacity test [14, 25]. After the mixing of the materials, they were stored in 100% humidity at 37°C for 48 hours to set.…”

Propriedades físico-químicas e biológicas de cimento experimental à base de Portland associado a diferentes radiopacificadores

“…(HOLLAND, et al, 2001a;DUARTE, et al, 2003;MAROTO, et al, 2005;DREGER, et al, 2012 (SANTOS, et al, 2005;CAMILLERI, 2007CAMILLERI, ,2008c. Os altos níveis de pH são, geralmente, verificados nos períodos iniciais, antes da completa presa dos cimentos, sendo o mesmo verificado no estudo, corroborando com outros estudos (DUARTE, et al, 2003;DE VASCONCELOS, et al, 2009;VIVAN, et al, 2010;SILVA, et al, 2014). O nível do pH diminuiu com o tempo, porém se manteve alcalino.…”