Objective The study assessed the cytotoxicity and immunomodulatory/anti-inflammatory effect of extract from zinc oxide–eugenol (ZOE)-based dental materials during setting using immortalized human dental pulp stem cells (IHDPSCs) and mouse bone marrow monocytes (IMBMMs), and identified the responsible extract component. Methods In accord with the ISO 10993-12, we extracted a mixture of ZOE cement and sealer after a specified time. The extract was analyzed by two types of mass spectrometry (ICP-MS and GC–MS). Cell viability was evaluated with extract and serial concentrations of ZnCl2, ZnSO4, and eugenol liquid by WST assay. The immunomodulatory/anti-inflammatory effect of a ZOE component was determined by RT-PCR to detect the downregulatory effect of inflammatory mRNA expression after lipopolysaccharide (LPS)-induced inflammation. Results Zn2+ and eugenol (2–20 ppm) were detected in the ZOE cement and sealer extracts. During the early stage of setting, significant cytotoxicity was observed in IHDPSCs and IMBMMs (p < 0.05). The half maximal effective concentration of Zn2+ was 5–8 ppm, whereas that of eugenol could not be detected within 80 ppm. After extract treatment, the expression of inflammatory mRNA was significantly lower in inflamed IHDPSCs, but not inflamed IMBMMs, than in the LPS control (p < 0.05). However, eugenol, not Zn2+, at 5–20 ppm downregulated inflammatory mRNA expression in the inflamed IMBMMs with and without the exchange of LPS-pretreated medium. Significance ZOE was highly cytotoxic, especially during setting, to both cells due to Zn2+ while the immunomodulatory/anti-inflammatory effect of ZOE was induced by eugenol.
Bibliographical notePublisher Copyright:
© 2016 The Academy of Dental Materials
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials