Mineral trioxide aggregate immersed in sodium hypochlorite reduce the osteoblastic differentiation of human periodontal ligament stem cells

Abstract

White mineral trioxide aggregate (WMTA) is a root canal treatment material, which is known to exhibit a dark brown color when in contact with sodium hypochlorite solution (NaOCl). This study aimed to investigate the effects of NaOCl on the surface properties of WMTA discs and WMTA-induced osteoblastic differentiation of periodontal ligament stem cells (PDLSCs). Mixed WMTA (ProRoot MTA) was filled into the molds to form WMTA discs. These discs were immersed in distilled water (D-WMTA) or 5% NaOCl (Na-WMTA). Their surface structures and Ca2+ release level was investigated. Moreover, they were cultured with a clonal human PDLSC line (line 1–17 cells). The main crystal structures of Na-WMTA were identical to the structures of D-WMTA. Globular aggregates with polygonal and needle-like crystals were found on D-WMTA and Na-WMTA, which included Ca, Si, Al, C and O. However, many amorphous structures were also identified on Na-WMTA. These structures consisted of Na and Cl, but did not include Ca. NaOCl immersion also reduced Ca2+ release level from whole WMTA discs. Line 1–17 cells cultured with D-WMTA formed many mineralized nodules and exhibited high expression levels of osteoblast-related genes. However, cells incubated with Na-WMTA generated a small number of nodules and showed low expression levels of osteoblast-related genes. These results indicated that NaOCl reduced Ca2+ release from WMTA by generating amorphous structures and changing its elemental distribution. NaOCl may also partially abolish the ability of WMTA to stimulate osteoblastic differentiation of PDLSCs.

Effect of Sodium Hypochlorite and Ethylene Diamine tetra-acetic acid on The Push-out Bond Strength and Sealing Ability of Different Bioceramic Root Repair Materials. (In Vitro Study)

“…In our study, the negative effect of the NaOCl on the white MTA Angelus group can be explained by the study of Zapf AM et al (13) who found that mixing the MTA with NaOCl significantly reduces the Ca(OH) 2 formation. And another study by Yamashita, Kozue, et al (14) reported that NaOCl immersion inhibited the formation of Ca(OH) 2 on the surfaces of set white MTA discs which can have a detrimental effect on the properties of the MTA including the push-out bond strength and sealing ability. Also, NaOCl inhibited WMTA-induced mineralized nodule formation Therefore, NaOCl should be firmly removed from root canals that are repaired by white MTA after root canal treatment to maintain its ability to stimulate hard tissue formation.…”

Involvement of M1/M2 Macrophage Polarization in Reparative Dentin Formation

“…During the injury repair of dental pulp tissue, the process of the odontoblastic differentiation of DPSCs is essential for synthesizing the reparative dentin at the pulp exposure site. MTA has been reported to release calcium ions [39,40] and induce reparative dentin after the pulp exposure when it is applied as a direct pulp capping material [41][42][43][44]. We previously reported that CaCl 2 induces mineralization and odontoblastic differentiation of dental pulp cells [45].…”

Leaching and cytotoxicity of bismuth oxide in ProRoot MTA – A laboratory investigation

“…The leaching of chemicals from a material into solution are likely to influence biological responses to that material (Faraji et al, 2022;Sanchez et al, 2012). Several studies have investigated the effect of ProRoot MTA in cultures of human dental pulp cells (Li et al, 2018;Rathinam et al, 2015Rathinam et al, , 2021, periodontal ligament cells (Pelepenko et al, 2021;Yamashita et al, 2021), alveolar bone marrow stem cells (Margunato et al, 2015;Sultana et al, 2018), stem cells from the apical papilla (Peters et al, 2016;Sanz et al, 2020), osteoblasts (Ciasca et al, 2012), rat pulp cells (RPC-C2A) and human lung fibroblasts (MRC-5) (Koulaouzidou et al, 2008). These studies generated varied conclusions regarding cell responses to the material depending on the cell type; however, the described effects were related to the cement rather than the bismuth oxide.…”