Current status on antimicrobial activity of a tricalcium silicate cement

Interfacial assessment of cention forte vs. equia forte and two forms of calcium silicate cements at two time intervals

AIM

Assessment of interfacial gaps and mechanical impact of the materials layering between Cention Forte and Equia Forte restorations with two forms of Calcium Silicate Cements (CSCs) at the interfacial surface at two-time intervals.

METHODOLOGY

Six groups of 72 primary molars were categorized by restorative material type and CSCs: Cention Forte(C), Cention Forte without primer (Cx), and Equia Forte (EQ). All were applied over MTA Angelus powder (M) or Bio-C Repair putty (P). Restorative materials were applied immediately (subgroup A) or delayed (Subgroup B). SEM was used to detect interface gaps. EDX measured element migration from the interface at specific distances. Vickers Microhardness Tester assessed microhardness.

RESULTS

Regarding SEM, there were no gaps between CSCs interfaces of both types (Powder and Putty) with all restorations at two-time intervals. Microhardness, there was a statistically nonsignificant difference between subgroups A & B in all groups except at 200 µm in the Cention groups (subgroup A) was significantly lower than (subgroup B) (P = 0.002, 0.03) respectively. At 400 µm in the MTA Angelus powder Group Cx, subgroup A was significantly higher than subgroup B (P = 0.003*). While Bio-C Repair putty in Group EQ (subgroup A) was significantly higher than (Subgroup B) (P < 0.0001*).

CONCLUSIONS

The delayed application of Cention Forte over two types of CSCs is useful in getting the maximum HV and, in turn, the long survival rate of the filling. Immediate application of Cention Forte without primer is better over both types of CSCs. The delayed application of Equia Forte over MTA angelus powder is more considerable.

Bioceramics in Endodontics: Updates and Future Perspectives

Bioceramics, with excellent bioactivity and biocompatibility, have been widely used in dentistry, particularly in endodontics. Mineral trioxide aggregate (MTA) is the most widely used bioceramic in endodontics. Recently, many new bioceramics have been developed, showing good potential for the treatment of endodontic diseases. This paper reviews the characteristics of bioceramics and their applications in various clinical endodontic situations, including root-end filling, root canal therapy, vital pulp therapy, apexification/regenerative endodontic treatment, perforation repair, and root defect repair. Relevant literature published from 1993 to 2023 was searched by keywords in PubMed and Web of Science. Current evidence supports the predictable outcome of MTA in the treatment of endodontic diseases. Although novel bioceramics such as Biodentine, EndoSequence, and calcium-enriched mixtures have shown promising clinical outcomes, more well-controlled clinical trials are still needed to provide high-level evidence for their application in endodontics. In addition, to better tackle the clinical challenges in endodontics, efforts are needed to improve the bioactivity of bioceramics, particularly to enhance their antimicrobial activity and mechanical properties and reduce their setting time and solubility.

In vitro investigation of the impact of contemporary restorative materials on cariogenic bacteria counts and gene expression

OBJECTIVES

The aim of this study was to compare the antibacterial effect of different fluoride-containing and bioactive restorative materials, and their effect on the expression of specific biofilm-associated genes and therefore the caries process.

MATERIALS AND METHODS

The restorative materials utilized in this study included: 1. Filtek Z250, 2. Fuji II LC, 3. Beautifil II, 4. ACTIVA, and 5. Biodentine. For each material, disc-shaped specimens were prepared. The inhibitory effects against Streptococcus mutans, Lactobacillus acidophilus, and Leptotrichia shahii were tested. After incubation for 24 hours and 1 week, colony-forming units (CFUs) were enumerated. From the plates dedicated for biomass quantification and RNA purification, the target glucosyltransferase B (gtfB) and glucan-binding protein B (gbpB) genes were chosen for S. mutans. For L. acidophilus, a gene involved in exopolysaccharide synthesis (epsB) was chosen.

RESULTS

Except for Filtek Z250, all four materials showed statistically significant inhibitory effects on the biofilms of all three species. When biofilms were grown in the presence of the same four materials, the expression of S. mutans gtfB and gbpB genes, was significantly reduced. For L. acidophilus, the decrease in the expression of gtfB gene in the presence of ACTIVA was the highest change seen. The epsB gene expression also decreased. Compared to fluoride-releasing materials, bioactive materials had more inhibitory effect against L. acidophilus, both at 24 hours and 1 week.

CONCLUSIONS

Both fluoride releasing and bioactive materials exhibited a significant inhibitory effect on the biofilm growth. The expression of the targeted biofilm-associated genes was downregulated by both material groups.

CLINICAL SIGNIFICANCE

The findings from this study give insight into the antibacterial effect of fluoride-containing and bioactive materials which would help to reduce the chances for secondary caries and therefore increase the lifetime of dental restorations placed for patients.

An in vitro evaluation of antimicrobial activity of a fast-setting endodontic material

The aim of this study is to evaluate the antimicrobial activity of the fast-setting iRoot Fast Set Root Repair Material (iRoot FS), Mineral trioxide aggregate (MTA) and Biodentine. The materials were freshly mixed or set for 1 and 7 days to conduct the agar diffusion test, direct contact test and carry-over effect test against E. faecalis and P. gingivalis, and the pH values were also measured. The data were analyzed by an analysis of variance and one-way ANOVA or Dunnett's T3 test, and the Tukey's post hoc test for multiple comparisons (α = 0.05). In the direct contact test, all three materials showed good antibacterial activity after setting for 20 min. The antibacterial properties of the three materials decreased with the increase of setting time (p < 0.05). The suspension of all the three materials showed high pH values (11-12) and no significant difference was observed (p > 0.05). With the extension of setting time, the pH of iRoot FS and Biodentine slightly decreased (p < 0.05). Fresh iRoot FS, Biodentine, and MTA killed E. faecalis and P. gingivalis effectively, but their antimicrobial effect decreased after 24 h, and distinctly decreased after 7 days after mixing. iRoot FS, Biodentine, and MTA showed a tendency of alkalinity during this 7-day experiment.