Antimicrobial and Antibiofilm Properties of Bioceramic Materials in Endodontics

Biological properties versus solubility of endodontic sealers and cements

Endodontic sealers and cements used in root canal treatment have different compositions and properties. Common to all materials is that their primary goal is to fill gaps and voids, making a permanent seal of the root canal system. Furthermore, aspects such as antibacterial properties, cytotoxicity, setting time, solubility and biocompatibility are also crucial and ought to be considered. Over the years, a shift in the view on the importance of these aspects has ocurred. Whereas the antibacterial properties were considered important when the technical factors in endodontics were less developed, the sealing ability and biocompatibility have later been considered the most critical factors. The introduction of tricalcium silicate cements and sealers has led to a renewed interest in material properties, as these cements seem to have good sealing ability and at the same time combine favourable antimicrobial effects with excellent biocompatibility. This review discusses how the various properties of root canal sealers and cements may conflict with the primary aim of providing a permanent seal of the root canal system.

An in vitro evaluation of endodontic sealers and an antibiotic to assess their antimicrobial effect against Enterococcus faecalis

Objective

This study aimed to compare the antimicrobial effect of three endodontic sealers (AH Plus, Mineral trioxide aggregate [MTA] Fillapex, and BioRoot RCS) with and without amoxicillin against E. faecalis.

Methodology

Amoxicillin, equivalent to 10% of the sealers' total weight, was mixed with the sealers. Another batch was prepared without amoxicillin. The direct contact test (DCT) and the agar diffusion test were used to assess the antibacterial effect. Results were analysed using one-way analysis of variance (ANOVA), the F-test, and the Kruskal-Wallis test.

Results

AH Plus significantly suppressed E. faecalis without the addition of amoxicillin in the DCT (p = 0.011), while in the agar diffusion test, BioRoot RCS had a larger inhibition zone than the control (p < 0.001). When amoxicillin was added to the sealers, AH Plus (p = 0.003) and MTA Fillapex (p = 0.042) reduced E. faecalis growth. In contrast, all three sealers showed larger inhibition zones than the control (p = 0.001), with AH Plus displaying a larger inhibition zone than MTA Fillapex (p = 0.042) and BioRoot RCS (p = 0.032).

Conclusions

It was thus concluded that the addition of amoxicillin to endodontic sealers enhances their antimicrobial activity against E. faecalis.

Antimicrobial Peptide- and Dentin Matrix-Functionalized Hydrogel for Vital Pulp Therapy via Synergistic Bacteriostasis, Immunomodulation, and Dentinogenesis

The preservation of vital pulps is crucial for maintaining the physiological functions of teeth; however, vital pulp therapy (VPT) of pulpitis teeth remains a substantial challenge due to uncontrolled infection, excessive inflammation, and limited regenerative potential. Current pulp capping agents have restricted effects in the infectious and inflammatory microenvironment. To address this, a multifunctional hydrogel (TGH/DM) with antibacterial, immunomodulatory, and mineralization-promoting effects is designed. The antimicrobial peptide (AMP) and demineralized dentin matrix are incorporated into the hydrogel, achieving sustainable delivery of AMP and a cocktail of growth factors. In vitro results show that TGH/DM could kill endodontic microbiota, ameliorate inflammatory responses of human dental pulp stem cells (hDPSCs), and prompt odontogenic differentiation of inflammatory hDPSCs via activation of peroxisome proliferator-activated receptor gamma. In vivo results suggest that TGH/DM is capable of inducing M2 phenotype transformation of macrophages in mice and fostering the regeneration of the dentin-pulp complex in inflamed pulps of beagle dogs. Overall, this study first proposes the synergistic regulation of AMP and tissue-specific extracellular matrix for the treatment of pulpitis, and the advanced hydrogel provides a facile and effective way for VPT.

Characterization and Assessment of Physical Properties of 3 Single Syringe Hydraulic Cement-based Sealers

INTRODUCTION

A number of sealers with different chemistries are badged as Bioceramic, implying biological activity, but have dissimilar properties, which has implications on the sealer properties and will affect the quality and outcome of root canal treatment. This study aimed to assess the physical and chemical properties of 3 hydraulic cement-based sealers, namely BC Universal sealer compared with Totalfill BC sealer and AH Plus Bioceramic.

METHODS

The microstructure and composition of the sealers were assessed using scanning electron microscopy and energy dispersive spectroscopy after setting. The crystalline phases were assessed by X-ray diffraction analysis and the leachates were tested using inductively coupled plasma. All testing was performed at 0, 7, and 28 days. The physical properties of film thickness, flow, radiopacity, and solubility were evaluated using ISO 6876:2012 standards.

RESULTS

All 3 sealers contained calcium, zirconium, and silicon. Totalfill BC had the highest calcium release at 7 and 28 days followed by AH Plus Bioceramic and BC Universal sealer. All 3 sealers adhered to the ISO standard in terms of flow and radiopacity. BC Universal sealer was slightly over the range (>50 μm) for film thickness. All sealers exceeded the solubility range set by ISO 6876:2012.

CONCLUSION

Although these hydraulic cement sealers had similar components and delivery, the properties varied significantly. The testing of material properties to confirm the suitability for clinical use is necessary.

Bridging the Gap between Endodontic Failure and Success: A Case Report on Intentional Replantation

This case report describes a case of intention replantation in a 15-year-old patient with a mandibular permanent right second molar that had undergone root canal treatment previously. The tooth was tender on percussion. Radiographic evaluation showed the presence of a separated instrument and periapical radiolucency. The surgical procedure was performed under local anesthesia, and the tooth was extracted. After cleaning and disinfecting the root canal system, the tooth was reimplanted, and the socket was filled with a mixture of bone graft material and a growth factor. A stainless steel crown was then placed to protect the tooth. A follow-up examination was performed after 12 months. The clinical and radiographic examinations revealed a well-healing periapical lesion with no signs of infection. The patient was asymptomatic, and the tooth was functional. The results of this case indicate that intentional replantation can lead to a favorable outcome.

A comparative study of biological properties of three root canal sealers

OBJECTIVES

The aim of this study was to evaluate the effects of Hiflow with other two kinds of root canal sealers on the biological behavior of stem cells from the apical papilla (SCAP), the influence on inflammatory cytokines release and its antibacterial effects.

MATERIALS AND METHODS

Material extracts of Hiflow, iRoot SP, and AH Plus were prepared. Then, SCAP was incubated with extracts. The effects were evaluated by CCK-8, wound healing assay, ALP staining, alizarin red staining, and qRT-PCR. Meanwhile, polymorphonuclears (PMNs) and monocytes were isolated and treated with extracts for 4 h and 24 h respectively. Cell viability was analyzed by Annexin-V/PI double staining flow cytometry. The effects on the release of cytokines were observed by ELISA. The antibacterial effects of different sealers were tested against three kinds of bacteria found in chronic apical periodontitis.

RESULTS

A series of results of SCAP showed that Hiflow and iRoot SP could promote cell proliferation, migration, and osteogenesis (p < 0.05). Although Hiflow was associated with greater cell apoptosis and necrosis when incubated with PMNs and monocytes (p < 0.05), it had an approximate release of anti-inflammatory cytokines with iRoot SP, which was higher than AH plus (p < 0.05). The co-culture showed that Hiflow and iRoot SP inhibited the colony formation of F. nucleatum (p < 0.05). However, both sealers had no obvious antibacterial effect on E. faecalis and P. gingivalis (p > 0.05).

CONCLUSIONS

In summary, Hiflow and iRoot SP both had positive biological stimulus on SCAP. Meanwhile, Hiflow showed a better induction on anti-inflammatory cytokines over the others. All the properties mentioned above and its antibacterial effect of F. nucleatum promise Hiflow a bright application prospect in endodontic uses.

CLINICAL RELEVANCE

References for clinical work to use BC Sealer Hiflow as a good biological root canal sealer.

Nanomaterials Modulating the Fate of Dental-Derived Mesenchymal Stem Cells Involved in Oral Tissue Reconstruction: A Systematic Review

The critical challenges in repairing oral soft and hard tissue defects are infection control and the recovery of functions. Compared to conventional tissue regeneration methods, nano-bioactive materials have become the optimal materials with excellent physicochemical properties and biocompatibility. Dental-derived mesenchymal stem cells (DMSCs) are a particular type of mesenchymal stromal cells (MSCs) with great potential in tissue regeneration and differentiation. This paper presents a review of the application of various nano-bioactive materials for the induction of differentiation of DMSCs in oral and maxillofacial restorations in recent years, outlining the characteristics of DMSCs, detailing the biological regulatory effects of various nano-materials on stem cells and summarizing the material-induced differentiation of DMSCs into multiple types of tissue-induced regeneration strategies. Nanomaterials are different and complementary to each other. These studies are helpful for the development of new nanoscientific research technology and the clinical transformation of tissue reconstruction technology and provide a theoretical basis for the application of nanomaterial-modified dental implants. We extensively searched for papers related to tissue engineering bioactive constructs based on MSCs and nanomaterials in the databases of PubMed, Medline, and Google Scholar, using keywords such as "mesenchymal stem cells", "nanotechnology", "biomaterials", "dentistry" and "tissue regeneration". From 2013 to 2023, we selected approximately 150 articles that align with our philosophy.

Antimicrobial Activity of Five Calcium Silicate Based Root Canal Sealers against a Multispecies Engineered Biofilm: An In Vitro Study

AIM

The present study's objective was to compare the impact of CerasealR, total fill BC SealerR, Bio-C SealerR, AH Plus BioceramicR, and K-BiocerR on the elimination of a multispecies' endodontic biofilm at 3, 7 and 14 days.

MATERIALS AND METHODS

A total of 20 freshly extracted, caries-free premolars were prepared for the study to create dentinal disks. For the multispecies biofilm formation, Enterococcus faecalis, Proteus mirabilis, Pseudomonas aeruginosa, and Candida albicans were cultured and used to inoculate hydroxyapatite discs. After incubation, the biofilms were placed on blotting papers in petri dishes with an orthodontic bend. Different root canal sealers, including CeraSeal, total Fill BC Sealer, Bio-C Sealer, AH Plus Bioceramic, K-Biocer, and Sealite, were injected into the bend, facilitating contact with the biofilms. The samples were divided into seven groups, including a negative control. At specific intervals, 3, 7, and 14 days, 3 biofilm samples from each group were collected, diluted, and plated on Agar media for colony counting and analysis.

RESULTS

In all tested groups, the total bacterial count significantly decreased between day 3 and 14 (p < 0.05) with no statistically significant differences among the different sealers' groups at all-time points for the total bacterial count, E. faecalis count, and P. mirabilis count. However, Sealite demonstrated the most consistent effectiveness in reducing bacterial counts across multiple categories. The sealite group was capable of decreasing the C. albicans count significantly between day 3 and day 14 (p < 0.05) in comparison with the bioceramic groups.

CONCLUSION

All sealers had antibacterial activity against the multispecies biofilm between day 3 and day 14. The ascending order of sealers in terms of their effectiveness in killing bacteria, based on the provided results, is as follows: Sealite, Bio-C Sealer, AH Plus, CeraSeal, TotalFill, and K-Biocer. However, there were no statistically significant differences in the bacterial counts among the different sealer groups at any time point.

CLINICAL SIGNIFICANCE

The role of sealers in combating biofilm-associated infections highlights their potential clinical utility in preserving root canal health. Understanding the antimicrobial properties of these sealers is vital for informed decision-making in selecting the most effective materials for improved treatment outcomes and long-term success in endodontic procedures.

A critical review of the material properties guiding the clinician's choice of root canal sealers

OBJECTIVES

The introduction of hydraulic cement sealers has increased the popularity of single cone obturation where the chemistry and properties of hydraulic cement sealers are crucial. This article has investigated the materials present on the market by reviewing the chemistry aiming at understanding whether these materials are optimized or have been tested appropriately.

METHODOLOGY

A market search on materials called bioceramic and hydraulic sealers was undertaken. The safety data sheet and manufacturer details for every material were searched and the components were checked. The literature was searched for information about the properties of these materials based on their composition.

RESULTS

The safety data sheets and manufacturer details were imprecise with some manufacturers providing little detail on composition. From the publications reviewed, it is apparent that the materials used clinically are not optimized, and there is little evidence that the material chemistry and presentation aid the clinical technique in any way.

CONCLUSIONS

There has been a rapid increase in materials identifying as bioceramics on the market. These materials have diverse chemistries, and some of the constituents are not declared. This may affect the clinical performance of these materials.

CLINICAL SIGNIFICANCE

Smart materials developed on the clinical need which are appropriately tested are necessary for a paradigm shift in root canal obturation. It is important to use reputable materials that have been adequately researched in clinical practice.

The Efficacy of Er:YAG Laser-Activated Shock Wave-Enhanced Emission Photoacoustic Streaming Compared to Ultrasonically Activated Irrigation and Needle Irrigation in the Removal of Bioceramic Filling Remnants from Oval Root Canals-An Ex Vivo Study

The removal of filling material is important for successful root canal retreatment. The aim of the study was to compare the efficiency of two activated irrigation techniques, the shock wave-enhanced emission photoacoustic streaming (SWEEPS) mode of the Er:YAG laser and ultrasonically activated irrigation (UAI) and a conventional syringe-needle technique (SNI), in the removal of bioceramic sealer/gutta-percha during conventional retreatment in oval root canals. The study sample consisted of distal root canals of 42 extracted human mandibular molars, which were prepared using a ProTaper Next system up to size 40/0.06 and filled with bioceramic sealer using a single-cone obturation technique. The teeth were then re-treated with a Reciproc Blue RB40 file and 3% sodium hypochlorite solution. The prepared teeth were randomly divided into three groups (n = 14 per group) and subjected to one of the three irrigation methods. Micro-CT scans were performed at different stages to assess the amount of filling material after each retreatment phase. The results of the study showed that all the tested irrigation techniques reduced a statistically significant amount of the remnant filling material at retreatment (p < 0.05), and there were no statistically significant differences in efficacy between the three methods. All tested techniques had similar efficacy in the removal of the remaining filling remnants.

Bioceramics utilization for the repair of internal resorption of the root: A case report

BACKGROUND

The objective of this work is displaying a successful treatment for an internal resorption case under operating microscope using bioceramic material.

CASE SUMMARY

Periapical radiograph showed radiolucent lesion representing large internal resorption of the root. The respective defect was obturated using endoscquence bioceramic material follow up at the month 18 after treatment revealed no abnormal finings clinically and radiographically.

CONCLUSION

New generations bioceramics have many advantages that internal root resorption cases can benefit from. The use of operating microscope helps to apply obturating materials with precision. However, long term study on a large sample is required in future studies.