Antimicrobial and physical properties of experimental endodontic sealers containing vegetable extracts

Abstract

To assess the antimicrobial activity and the physical properties of resin-based experimental endodontic sealers with the incorporation of vegetable extracts obtained from Bixa orellana, Mentha piperita, and Tagetes minuta species. The extracts were obtained and characterized by gas chromatography-mass spectrometry (GC-MS), and minimum inhibitory concentration (MIC) against Streptococcus mutans, Enterococcus faecalis, and Candida albicans. The extracts were individually incorporated into a dual-cure experimental sealer at a mass concentration of 0.5%. A commercial reference RealSeal was used. The sealers were evaluated by measuring the setting time, degree of conversion, dimensional stability, radiopacity, flow, and film thickness of these materials, also and its antimicrobial effect was evaluated using the direct contact test. Data were statistically analyzed by analysis of variance and Tukey's post-hoc test at α = 0.05 significance level. The physical properties were not influenced by the addition of the vegetable extracts (p > 0.05). For S. mutans, only T. minuta and B. orellana groups presented antibacterial activity after 24 h of contact (p < 0.05). All extracts evidenced an antibacterial effect against E. faecalis (p < 0.05). The experimental sealers hold promise as a novel vegetable sealer with great antimicrobial activity and also great physical-mechanical properties. Nonetheless, more studies are needed.

Figure 1

Radiopacity in mmAl of the endodontic sealers evaluated. Different lowercase letters indicate the presence of statistically significant differences (p < 0.05). Control group = Experimental endodontic sealer with no added vegetable extracts.

Figure 2

Antimicrobial effects of the test materials. Columns under the same horizontal line indicate no differences between different incubation times (1 h or 24 h). Uppercase letters indicate differences between endodontic sealers at 1 h of incubation time. Lowercase letters indicate differences between endodontic sealers at 24 h of incubation time. Numbers above columns indicate the percentage of log¹⁰ reduction when compared to the microbial growth. Control group = Experimental endodontic sealer with no addition of tincture or oils.