Physicochemical and Antibacterial Properties of Novel, Premixed Calcium Silicate-Based Sealer Compared to Powder-Liquid Bioceramic Sealer

Abstract

The aim of this study was to compare the physicochemical properties, filling ability, and antibacterial activity of a premixed calcium silicate-based sealer to those of a powder-liquid bioceramic sealer. Ceraseal (CS) and BioRoot (BR) materials were analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy at 7 and 14 d of immersion in distilled water. The filling ability of the two sealers as well as the water contact angle, solubility, flow, roughness, crystalline microstructure, pH, and compressive strength were also evaluated. The antibacterial activity was assessed through an agar diffusion as well as through direct tests. All the results were statistically analyzed using one-way or two-way analysis of variance tests. Statistically significant lower void percentages were observed for CS at 2 and 8 mm from the working length (WL) compared to those for the BR group, whilst no significant difference was observed at 5 mm from the WL. BR sealer showed higher alkaline pH, rougher surface, lower water contact angle values, lower flowability, and higher solubility compared to CS. BR showed globular and needle-like crystalline microstructure, whilst CS had globular and flower-like crystalline microstructure up to 72 h. No statistical difference was found for the compressive strength between the two sealers. BR and CS showed no antibacterial effect against Enterococcus faecalis after 3 h, whilst both sealers showed antibacterial capacity after 24 and 72 h. BR demonstrated higher antibacterial activity after 24 h. In conclusion, the use of bioceramic sealers may play an important role in controlling bacterial growth. Moreover, CS may have superior filling ability and lower solubility than the BioRoot sealer due to its specific chemical composition and mixing method.

Keywords: antibacterial activity; bioceramic sealer; calcium-silicate-based materials; filling ability; physicochemical properties.

Figure 1

(a–c) Cone-beam computed tomography (CBCT) analysis for teeth selection to ensure the following criteria: single canal, long/short diameter (ratio > 2), and root curvature (≤20°).

Figure 2

Digital microscope images. (a) Ceraseal, (b) BioRoot at 2 mm from the apex (200× magnification); (c) Ceraseal, (d) BioRoot at 5 mm from the apex (200× magnification); (e) Ceraseal, (f) BioRoot at 8 mm from the apex (100× magnification), showing an internal void (closed pores) (arrow).

Figure 3

Representative photos of scanning electron microscopy of sectioned root surfaces filled with (a,c,e,g) Ceraseal and (b,d,f,h) BioRoot. (a,b) Sealer–dentin interface; (e,f) infiltrations into dentinal tubules; (c,d) chemical analysis of the sealer in root canal; (g,h) chemical analysis of the infiltrations into dentinal tubules.

Figure 4

pH changes of water in contact with the sealer materials as a function of time for one week.

Figure 5

Representative scanning electron microscope images at 4000× magnification (a–h) and energy-dispersive X-ray (EDX) spectrums. The morphology and EDX spectrum observed for the BioRoot (a–d) and Ceraseal (e–h) surfaces after 24 and 72 h in humidity, 7 and 14 d in water at 37 °C.

Figure 6

Visual aspect of a water droplet (5 µL in initial volume) deposited onto different sealer surfaces (a) BioRoot; (b) Ceraseal, 10 s after its deposition. AFM micrographs (3D view, 10 µm²) of the BioRoot surface (c) and Ceraseal surface (d).

Figure 7

The inhibition zones around the different sealers and chlorhexidine (CHX) using agar diffusion test. BioRoot (BR) and Ceraseal (CS) materials infiltrated into agar materials.

Figure 8

Number of CFU (Colony Forming Unit) of Enterococcus faecalis in the presence of BioRoot, Ceraseal, and control group after 3, 24, and 72 h of culture; (* p < 0.05).