Dentin Enhances the Antibacterial Effect of Mineral Trioxide Aggregate and Bioaggregate

Thermophysical properties and bonding with composite resin of premixed mineral trioxide aggregate for use as base material

Dental bases require low thermal conductivity and good mechanical properties, such as bonding with composite resins. This study aims to elucidate the physicochemical properties of premixed mineral trioxide aggregate (MTA) for its suitability as a dental base and to explore the optimal adhesive strategy with composite resin. The thermal conductivity and compressive strength of this premixed MTA are 0.12 W/(m•K) and 93.76 MPa, respectively, Which are deemed adequate for its application as dental base. When bonded to composite resin, the use of 37% phosphoric acid etching before applying the Clearfil SE bond significantly reduced the bonding strength between composite resin and premixed MTA. This was because the compressive strength and Vickers hardness of premixed MTA decreased, and tricalcium silicate was dissolved from the surface during acid etching. Therefore, it is recommended to avoid using 37% phosphoric acid etching when bonding premixed MTA and composite resin as a dental base.

Clinical application of calcium silicate-based bioceramics in endodontics

Pulp treatment is extremely common in endodontics, with the main purpose of eliminating clinical symptoms and preserving tooth physiological function. However, the effect of dental pulp treatment is closely related to the methods and materials used in the process of treatment. Plenty of studies about calcium silicate-based bioceramics which are widely applied in various endodontic operations have been reported because of their significant biocompatibility and bioactivity. Although most of these materials have superior physical and chemical properties, the differences between them can also have an impact on the success rate of different clinical practices. Therefore, this review is focused on the applications of several common calcium silicate-based bioceramics, including Mineral trioxide aggregate (MTA), Biodentine, Bioaggregate, iRoot BP Plus in usual endodontic treatment, such as dental pulp capping, root perforation repair, regenerative endodontic procedures (REPs), apexification, root-end filling and root canal treatment (RCT). Besides, the efficacy of these bioceramics mentioned above in human trials is also compared, which aims to provide clinical guidance for their clinical application in endodontics.

Sol-Gel Technologies to Obtain Advanced Bioceramics for Dental Therapeutics

The aim of this work is to review the application of bioceramic materials in the context of current regenerative dentistry therapies, focusing on the latest advances in the synthesis of advanced materials using the sol-gel methodology. Chemical synthesis, processing and therapeutic possibilities are discussed in a structured way, according to the three main types of ceramic materials used in regenerative dentistry: bioactive glasses and glass ceramics, calcium phosphates and calcium silicates. The morphology and chemical composition of these bioceramics play a crucial role in their biological properties and effectiveness in dental therapeutics. The goal is to understand their chemical, surface, mechanical and biological properties better and develop strategies to control their pore structure, shape, size and compositions. Over the past decades, bioceramic materials have provided excellent results in a wide variety of clinical applications related to hard tissue repair and regeneration. Characteristics, such as their similarity to the chemical composition of the mineral phase of bones and teeth, as well as the possibilities offered by the advances in nanotechnology, are driving the development of new biomimetic materials that are required in regenerative dentistry. The sol-gel technique is a method for producing synthetic bioceramics with high purity and homogeneity at the molecular scale and to control the surfaces, interfaces and porosity at the nanometric scale. The intrinsic nanoporosity of materials produced by the sol-gel technique correlates with the high specific surface area, reactivity and bioactivity of advanced bioceramics.

In vitro antibacterial activity of endodontic bioceramic materials against dual and multispecies aerobic-anaerobic biofilm models

The aim of this in vitro study was to evaluate the antibacterial activity of calcium silicate repair cements and sealers against a dual-species planktonic aerobic model with different aging times and the ability to inhibit the formation of a mature 21-day-old multispecies anaerobic biofilm. The antibacterial activity of ProRoot MTA, MTA Angelus, Biodentine, BioRoot RCS and TotalFill BC sealer against a dual-species aerobic planktonic model, as well as measuring how materials were affected by aging, was evaluated using the Modified Direct Contact Test. Subsequently, the ability to inhibit the formation of a mature multispecies anaerobic biofilm was evaluated using scanning electron microscopy complemented with confocal laser scanning microscopy. Biodentine and BioRoot RCS had higher antibacterial action, and Biodentine was able to maintain its antibacterial action after a prolonged aging period in vitro. Calcium silicate repair cement MTA ProRoot and Biodentine had higher antibiofilm action.

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.

Chitosan Enhances the Anti-Biofilm Activity of Biodentine against an Interkingdom Biofilm Model

Endodontic infection is a biofilm disease that is difficult to irradicate with current treatment protocols, and as such, persistent micro-organisms may lead to ongoing or recurrent disease. The potential for the use of enhanced filling materials to modify biofilm regrowth is a promising strategy. This current study aimed to evaluate the anti-biofilm efficacy of calcium silicate cements modified with chitosan. The development of mono-species and multi-species biofilms on ProRoot MTA, Biodentine and bovine dentine discs were explored using quantitative microbiology analysis. The effect on regrowth of biofilms was assessed following the addition of chitosan to each cement. In comparison to a dentine substrate, both materials did not show the ability to inhibit biofilm regrowth. Biodentine incorporated with chitosan displayed a dose-dependent reduction in multi-species biofilm regrowth, unlike MTA. Notably, interkingdom biofilms were shown to enhance bacterial tolerance in the presence of chitosan. This study demonstrates the potential to enhance the antimicrobial properties of Biodentine. The findings highlight the need for appropriate model systems when exploring antimicrobial properties of materials in vitro so that interspecies and interkingdom interactions that modify tolerance are not overlooked while still supporting the development of innovative materials.

Antibiofilm potential over time of a tricalcium silicate material and its association with sodium diclofenac

OBJECTIVES

The objectives of this study are to investigate, over time, the antimicrobial activity against polymicrobial biofilms and ability to inhibit biofilm formation, of Biodentine (BD) alone and with 5% and 10% sodium diclofenac (DC).

MATERIAL AND METHODS

The antimicrobial activity of BD alone and modified with 5% and 10% DC against polymicrobial biofilm growth in dentin was determined by a modified direct contact test. The study groups were (1) BD; (2) BD + 5% DC; and (3) BD + 10% DC. The viability of microorganisms after 1 and 4 weeks was quantified by means of an ATP assay and flow cytometry. The antibiofilm efficacy of the materials, preventing polymicrobial biofilm formation over time, was assessed by confocal laser scanning microscopy (CLSM).

RESULTS

The results obtained with both the ATP test and flow cytometry showed that BD alone and with 5% and 10% DC exerted antibiofilm activity with respect to the control, in the two evaluated times (p < 0.001). Comparison between groups showed a tendency of increased antimicrobial effect, both over time and depending on the DC concentration. These results coincide with those obtained in CLSM analysis, where efficacy increased with time and DC concentration.

CONCLUSIONS AND CLINICAL RELEVANCE

Biodentine, over time, showed antimicrobial and antibiofilm efficacy on polymicrobial biofilms. The addition of 5% and 10% DC to BD enhanced this effect, in a concentration- and time-dependent manner.

A Systematic Review Comparing Mineral Trioxide Aggregate to Other Commercially Available Direct Pulp Capping Agents in Dogs

Vital pulp therapy (VPT) and direct pulp capping (DPC) are procedures regularly performed in dogs for the management of acute tooth fractures and as part of management for traumatic malocclusions. The purpose of this review is to apply an evidence-based medicine approach to systematically review and evaluate the scientific literature evaluating the efficacy of mineral trioxide aggregate (MTA) to other commercially available materials used for VPT in the permanent teeth of dogs. The 9 studies meeting inclusion criteria were reviewed and each studies evidence was classified using a grading system modified from the Oxford Centre for Evidence-Based Medicine. For the studies meeting inclusion criteria, MTA consistently performed as well or better than other commercially available products in terms of calcific barrier formation and biocompatibility. This review found a lack of consistency between the studies making a direct comparison of the results unreliable. Future studies would benefit from the implementation of a standard scoring system for histology, equivalent and longer study duration times and the correlation of histological and radiographic data.

Tissue reaction to novel customized calcium silicate cement based dental implants. A pilot study in the dog

OBJECTIVES

The purpose of this study was to determine the level of periodontal tissue regeneration in a canine model following post-extraction placement of an implant molded from a composite material made from extracted tooth dentin and a calcium silicate cement (CSC) material. The investigation used autologous dentin in conjunction with a CSC material to form a composite implant designed for immediate tooth replacement.

METHODS

Two (2) beagles had a periodontal and radiographic examination performed to rule out any pre-treatment inflammation, significant periodontal disease, or mobility. Then, ination eleven (11) teeth were extracted and polyvinyl siloxane molds were made to fabricate three different types of implants: Particulate Implant (Test Group 1, n = 4), Shell Implant Alone (Test Group 2, n = 2), Shell Implant with Emdogain® (Test Group 3, n = 3). Teeth in the control group were extracted, scaled (n = 2), and then re-implanted into their respective fresh extraction sockets. At 4 weeks, a clinical, radiographic, and histologic assessment was performed.

RESULTS

Clinical evaluation revealed no mobility in any of the test or control implants and no radiographic evidence of significant bone loss or active disease. Based on the MicroCT analysis, direct bone to implant contact was observed in some areas with an apparent periodontal ligament space. Implant-related inflammation, on average, was similar among all groups, with low numbers of infiltrates. Implant-related inflammatory reaction was generally minimal and not interpreted to be adverse.

CONCLUSION

The proposed novel composite materials revealed that not only do these materials demonstrate high biocompatibility, but also their successful integration in the alveolus is likely secondary to a partial ligamentous attachment. The current investigation may lead to the use of calcium silicate-based materials as custom dental implants. Further research on this novel composite's biomechanical properties is necessary to develop the optimal material composition for use as a load-bearing dental implant.

The presence of smear layer affects the antimicrobial action of root canal sealers

AIM

To assess the chemical and microstructural characteristics of dentine after the use of two irrigation protocols and correlate this with the antimicrobial properties of hydraulic calcium silicate cement (HCSC) sealers and changes to the dentine structure/chemistry after sealer placement.

METHODOLOGY

Two irrigation protocols - Protocol A using 2% NaOCl used 5 mL/5 min and Protocol B with 2% NaOCl (5 mL/5 min) followed by 17% EDTA (5 mL/3 min) - were used to prepare dentine. The chemical and microstructural changes following irrigation were assessed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and Fourier transform infrared (FT-IR) spectroscopy (n = 5) on dentine obtained from the mid-root and coronal parts of extracted human teeth. Four sealers (AH Plus, BioRoot, MTA Fillapex, TotalFill) were characterized by SEM/EDS (n = 3). The ability of the sealers to eradicate intratubular Enterococcus faecalis biofilms was assessed by live/dead dye and confocal laser scanning microscopy to measure the percentage of living cells. The effect of combined irrigation and root filling on dentine was assessed by SEM and EDS analysis (n = 5). Statistical analysis was undertaken using one-way anova and a number of post hoc tests to detect intergroup differences. The F-test was used for comparison of variances in the microbiology testing.

RESULTS

The use of NaOCl alone left the smear layer intact, with traces of chlorine remaining on dentine. The use of BioRoot sealer restored the calcium levels of dentine which had been depleted by the irrigation with EDTA. BioRoot exhibited antimicrobial properties against intratubular bacteria even in the presence of smear layer (Protocol A). Smear layer removal improved the bactericidal effect of all sealers and Ca²⁺ leaching. The use of a chelating agent was important for the intratubular sealer penetration for AH Plus but not the other sealers.

CONCLUSION

The removal of smear layer was necessary for penetration of AH Plus into the dentinal tubules. BioRoot was a more effective sealer in reducing the bacterial load in the dentinal tubules than the other materials tested and the presence of smear layer did not affect its activity.

In-vitro evaluation of microleakage of bioceramic root-end filling materials: A spectrophotometric study

Aim

To evaluate the microleakage of newer bioceramic root-end filling materials.

Material and method

Sixty freshly extracted human single-rooted mandibular premolar teeth were selected for the study. Teeth with fractured root, cracks, anddilacerations were rejected. All teeth were cleaned with ultrasonic scalers. Standard access opening was done and root canal treatment was performed with rotary files followed by obturation. After storing in saline for a week apical 3 ​mm of the root was resected at 900 angles to the long axis of the root. Retro cavity preparation was done with ultrasonic tips. The teeth were divided into four groups of 15 specimens each. Group I - Biodentin, GroupII-Bioaggregate, Group III - MTA Plus, and Group IV - MTA. After the restoration of retro cavities of all the teeth as per manufacture instructions, two coats of nail varnish were applied to leave apical 3 ​mm. All teeth were stored in 2% methylene blue for 72 ​h followed by emersion in 65% nitric acid for the next 72 ​h for Dye extraction. The obtained supernatant solution was then centrifuged and optical density or absorbance was measured with a UV spectrophotometer.

Result

Microleakage was found to be increasing in this order: Biodentin ​< ​Bioaggregate ​< ​MTA Plus ​< ​MTA. No significant difference was found in the microleakage of Biodentin compared to that of Bioaggregate(p ​> ​0.01).

Conclusion

All materials exhibit some amount of microleakage. Biodentin shows the least microleakage among all the bioceramic material groups. Hence, Biodentin and bioaggregate are better material of choice for the retrograde filling to prevent microleakage.

A Review of External Cervical Resorption

External cervical resorption (ECR) is a relatively uncommon yet aggressive form of dental hard tissue destruction. It is initiated at the cervical aspect of the root surface and extends apicocoronally and circumferentially inside the dentin. Despite the large number of case reports and clinical studies that have investigated ECR, its etiology remains unclear. Recent advancements in clinical assessment measures, such as the use of cone-beam computed tomographic imaging, have provided additional insights into the nature of this lesion. This has facilitated the continued development and improvement of treatment methods for this condition. In this article, we provide an overview of the latest research pertaining to the etiology, histopathology, predisposing factors, diagnosis, classification, and treatment of ECR. Furthermore, we provide a summary of the different classification schemes for ECR and highlight the relevant therapeutic principles.

Real-time nanoleakage and the flow characteristics of calcium silicate root canal filling materials

This study aimed to investigate the real-time nanoleakage and flow characteristics of calcium silicate-based (Ca-Si) root canal filling materials. Extracted human teeth (n = 30) were decoronated and standardized in their inner and outer dimensions. After root canal enlargement, the roots were filled with gutta-percha (GP) and AH26 sealer, GP and EndoSeal MTA sealer, or Biodentine. The roots were connected to a Nanoflow device (IB Systems) under hydrostatic pressure (40 cm∙H₂O) and fluid flow was traced through the filled roots. Data were detected at the nanoscale twice per second and automatically recorded in units of nL/s. Leakage was quantified as the mean slope until the curve plateaued over time, and all static flow intervals lasting longer than 1 s were analyzed to identify any increase in flow and duration. Data were statistically analyzed using the Kruskal-Wallis test. The calculated leakage values were 0.0670 ± 0.0516 nL/s for GP/AH26, 0.1397 ± 0.1579 nL/s for GP/EndoSeal MTA, and 0.0358 ± 0.0538 nL/s for Biodentine, with no statistically significant differences among the root filling materials (P > 0.05). An analysis of real-time flow data for 1000 s to identify spot trends and the overall tendency of flow until a plateau was reached revealed a stepwise increase in the roots filled with Ca-Si material, whereas the GP/AH26-filled roots showed a linear increase. Real-time measurements under hydrostatic pressure with the Nanoflow device enabled precise fluid flow tracing through the root canal filling material. In terms of nanoleakage, the tested root canal filling materials showed no significant differences, while the real-time flow patterns of roots filled with Ca-Si material showed different characteristics from those of GP/AH26-filled roots.

The Effect of Pulpotomy Base Material on Bacterial Penetration and Proliferation for Pulpotomized Primary Molar Teeth: A Confocal Laser Scanning Microscopy Study

Introduction: the study aimed to evaluate Enterococcus Faecalis colonization in the pulp chamber in pulpotomized extracted human teeth filled by different pulpotomy base materials (PBMs), using confocal laser scanning microscopy (CLSM). Study design: Cavity preparations were made in 70 extracted primary molars. The pulp chambers were filled using either Intermediate restorative material (IRM), Mineral Trioxide Aggregate (MTA) or Glass ionomer (GI). Twenty-five teeth served controls. The specimens were sterilized, and coronally filled with bacterial suspension for 21 days. The specimens were cut through the furcation area, stained using LIVE/DEAD BacLight Bacterial Viability Kit and evaluated using CLSM. Results: The extent of fluorescent staining was larger in the GI group, compared to the IRM and MTA groups, and larger in the IRM group compared to the MTA group (P<0.05). The minimal and maximal bacterial penetration depths into the dentinal tubules were 55 and 695&mu;m, respectively (mean 310&mu;m), without differences between the materials (GI, IRM, MTA, p>0.05). The ratio of live bacteria to dead bacteria within the evaluated areas was higher in the GI group compared to the IRM and the MTA groups, and higher in the IRM group compared to the MTA group (P<0.05). There were no differences between the mesial, distal and apical parts in any of the evaluations (p>0.05). Conclusions: bacteria colonize the interface between the PBM and dentin and penetrate deeply into the dentinal tubules. The extent and the vitality of the colonized bacteria may be affected by the type of PBM.

Wound Lavage in Studies on Vital Pulp Therapy of Permanent Teeth with Carious Exposures: A Qualitative Systematic Review

The aim of this study was to systematically review pulp wound lavage in vital pulp therapy (VPT). A search was conducted in six life science databases to identify clinical trials carried out on permanent teeth with a carious pulp exposure and a recall interval of at least six months. Twenty-seven trials of low to moderate risk of bias (RoB-2 and ROBINS-I) were included. Data was extracted and analyzed regarding study characteristics and methods used for pulp wound lavage. The agent used for pulp wound lavage was specified in all included trials. Most of the identified trials (23/27) randomized the pulp capping material. Many (14/27) reported the use of sodium hypochlorite (NaOCl); ten used only saline or water. One trial was identified that compared pulp wound lavage with 2.5% (NaOCl) to saline, another compared 5% glutaraldehyde to water, both in immature molar pulpotomies. Both studies were underpowered. Neither showed a significant difference between treatments. The use of NaOCl was positively correlated to recent year of publication and use of hydraulic calcium silicate cements for pulp capping (p < 0.05). In conclusion, despite a lack of well-designed trials on pulp wound lavage in VPT, a trend towards using NaOCl for this purpose was observed.

Detection, treatment and prevention of endodontic biofilm infections: what's new in 2020?

Endodontic disease, a biofilm infection of the root canal space, is a significant cause of dental morbidity worldwide. Endodontic treatment, or root canal treatment, as it is commonly known is founded on the ability to eradicate microbial biofilm infection and prevent re-infection of the highly complex root canal space. Despite many "advances" in clinical endodontics we have seen little improvement in outcomes. The aim of this critical review paper is to provide a contemporary view of endodontic microbiology and biofilm polymicrobiality, provide an understanding of the host response, and how together these impact upon clinical treatment. Ultimately, it is intended to provide insight into novel opportunities and strategies for the future diagnostics, treatment, and prevention of endodontic disease.

Immediate and Long-Term Porosity of Calcium Silicate-Based Sealers

INTRODUCTION

Open pores between endodontic sealer and root canal walls present potential niches for bacterial growth and migration pathways. The aim was to assess the internal and external porosity of calcium silicate-based sealers and to ascertain the long-term effect of storage in simulated body fluid on sealer porosity.

METHODS

Sixteen single-rooted teeth were filled with gutta-percha and 1 of 4 root canal sealers: BioRoot RCS, EndoSequence BC, MTA Fillapex, or AH Plus. Obturated roots, stored in Hank's balanced salt solution, were scanned after 7 days and after 6 months by using micro-computed tomography at an isotropic resolution of 9.9 μm. Total, open, and closed porosity were calculated in the coronal, middle, and apical thirds. Data were statistically analyzed by using general linear model and paired t test (α = 0.05).

RESULTS

Significantly higher percentage of open than closed porosity was found in all groups. Initially, significantly greater open and total porosity were found for MTA Fillapex than for AH Plus. After 6 months, the percentage of open and total porosity increased in BioRoot RCS and MTA Fillapex and decreased in AH Plus and EndoSequence BC. Both initially and after storage, coronal region of all sealers had significantly greater total porosity than middle and apical regions, which were comparable.

CONCLUSIONS

None of the root fillings were void-free, with predominant open porosity persisting after long-term storage.

Surface and vertical dimensional changes of mineral trioxide aggregate and biodentine in different environmental conditions

OBJECTIVES

Surface changes in biological environments are critical for the evaluation of physical and biological activity of biomaterials. Objective: This study investigated surface alterations of calcium silicate-based cements after exposure to different environments.

MATERIAL AND METHODS

Material and Methods: Forty-eight cylindrical cavities were prepared on root surfaces. The cavities were filled using ProRoot MTA or Biodentine and assigned to four subgroups (n=6): dry, wet, acidic, and blood. Surface topographies were evaluated using an optical profilometer for 28 days, and the roughness of the material surfaces was quantified. Vertical dimensional change was measured by determining the height difference between the material surface and the flat tooth surface. Data were compared with a two-way repeated measures ANOVA and Bonferroni tests.

RESULTS

Results: In dry condition, the surface roughness of MTA or Biodentine was constant up to 3 days (p>0.05) but decreased after 28 days (p<0.05). In dry condition, ProRoot MTA presented constant surface level through time, while Biodentine showed decreased surface level after 28 days. In wet condition, the roughness and the surface levels of both materials increased after 1 day (p<0.05). Neither the surface roughness nor the levels of the materials showed significant changes in acidic conditions (p>0.05). Both materials showed the highest roughness in blood conditions on the 1st day (p<0.05), while the surface roughness in blood decreased dramatically after 28 days. The roughness of Biodentine was higher in wet conditions up to 3 days compared with ProRoot MTA (p<0.05). Likewise, in blood condition, Biodentine showed higher roughness on the 28th day than ProRoot MTA (p<0.05).

CONCLUSIONS

Conclusions: Dry, wet, and blood conditions had a time-dependent effect on the surface roughness and vertical dimensional changes of the materials. However, acidic conditions did not affect the roughness and the surface level of the materials.

Combined endodontic and periodontal management of a class 3 invasive cervical resorption in a mandibular first molar

Dental radiography and cone-beam computed tomography revealed the left mandibular first molar in a 68-year-old female patient with Heithersay Class 3 invasive cervical resorption (ICR). The inhibition of ICR progression and environmental improvement in and around the affected tooth through combined endodontic and periodontal treatments led to a favorable clinical outcome.

Physicochemical and Biological Evaluation of Endodontic Filling Materials for Primary Teeth

This study assessed the pH, radiopacity, antimicrobial effect, cytotoxicity and biocompatibility of endodontic filling materials for primary teeth. Zinc oxide eugenol (ZOE), Vitapex and Calen paste thickened with zinc oxide (ZO) were evaluated in comparison to an experimental MTA-based material. Radiopacity was tested using a graduated aluminum stepwedge with a digital sensor (n=5). The materials pH was recorded at 1, 4, 12 h; 1, 3, 7, 15 and 30 days (n=5). Direct contact test was used to assess the antimicrobial efficacy against Enterococcus faecalis after 1, 4, 12, 24 h (n=5). Cytotoxicity assay used MTT test for cell viability after incubation for 1, 3 and 7 days (n=5). For biocompatibility test, Wistar rats had received implants containing each material (n=5). The biopsied tissues were histologically analyzed after 15, 30 and 60 days. The results of radiopacity, pH, antimicrobial capacity and cytotoxicity were analyzed using ANOVA and Tukey tests. The histological data were submitted to Kruskal-Wallis test. The experimental material presented the lowest radiopacity (3.28 mm Al) and had a pH>12.0 throughout the test period. The experimental material showed the highest antibacterial effect, killing over 99.97% bacteria in 4 h. Vitapex presented the highest cell viability. Initially, biocompatibility test showed moderate to severe inflammation in all groups. After 60 days, Calen+ZO group showed moderate inflammation, while the others showed predominantly mild inflammatory reaction. The present results demonstrated that the experimental MTA-based material exhibited satisfactory behavior regarding the studied properties. Additional in vivo studies are necessary for a better evaluation of the material.

Retention of BioAggregate and MTA as coronal plugs after intracanal medication for regenerative endodontic procedures: an ex vivo study

Objectives

This study compared the retention of BioAggregate (BA; Innovative BioCeramix) and mineral trioxide aggregate (MTA; Angelus) as coronal plugs after applying different intracanal medications (ICMs) used in regenerative endodontics.

Materials and Methods

One-hundred human maxillary central incisors were used. The canals were enlarged to a diameter of 1.7 mm. Specimens were divided into 5 groups (n = 20) according to the ICM used: calcium hydroxide (CH), 2% chlorhexidine (CHX), triple-antibiotic paste (TAP), double-antibiotic paste (DAP), and no ICM (control; CON). After 3 weeks of application, ICMs were removed and BA or MTA were placed as the plug material (n = 10). The push-out bond strength and the mode of failure were assessed. The data were analyzed using 2-way analysis of variance, the Tukey's test, and the χ² test; p values < 0.05 indicated statistical significance.

Results

The type of ICM and the type of plug material significantly affected bond strength (p < 0.01). Regardless of the type of ICM, BA showed a lower bond strength than MTA (p < 0.05). For MTA, CH showed a higher bond strength than CON, TAP and DAP; CHX showed a higher bond strength than DAP (p < 0.01). For BA, CH showed a higher bond strength than DAP (p < 0.05). The mode of failure was predominantly cohesive for BA (p < 0.05).

Conclusions

MTA may show better retention than BA. The mode of bond failure with BA can be predominantly cohesive. BA retention may be less affected by ICM type than MTA retention.

Mineral trioxide aggregate enriched with iron disulfide nanostructures: an evaluation of their physical and biological properties

The purpose of this study was to characterize mineral trioxide aggregates (MTA) enriched with iron disulfide (FeS₂ ) nanostructures at different concentrations, and to investigate their storage modulus, radiopacity, setting time, pH, cytotoxicity, and antimicrobial activity. Iron disulfide nanostructures [with particle size of 0.357 ± 0.156 μm (mean ± SD)] at weight ratios of 0.2, 0.4, 0.6, 0.8, and 1.0 wt% were added to white MTA (wMTA). The radiopacity, rheological properties, setting time, and pH, as well as the cytotoxicity (assessed using the MTT assay) and antibacterial activity (assessed using the broth microdilution test) were determined for MTA/FeS₂ nanostructures. The nanostructures did not modify the radiopacity values of wMTA (~6 mm of aluminium); however, they reduced the setting time from 18.2 ± 3.20 min to 13.7 ± 1.8 min, and the storage modulus was indicative of a good stiffness. Whereas the wMTA/FeS₂ nanostructures did not induce cytotoxicity when in contact with human pulp cells (HPCs) and human gingival fibroblasts (HGFs), they showed bacteriostatic activity against Staphylococcus aureus, Escherichia coli, and Enterococcus faecalis. Adding FeS₂ nanostructures to MTA might be an option for improving the root canal sealing and antibacterial effects of wMTA in endodontic treatments.

Mineral Trioxide Aggregate-A Review of Properties and Testing Methodologies

Mineral trioxide aggregate (MTA) restoratives and MTA sealers are commonly used in endodontics. Commonly referenced standards for testing of MTA are ISO 6876, 9917-1 and 10993. A PubMed search was performed relating to the relevant tests within each ISO and "mineral trioxide aggregate". MTA restoratives are typically tested with a mixture of tests from multiple standards. As the setting of MTA is dependent upon hydration, the results of various MTA restoratives and sealers are dependent upon the curing methodology. This includes physical properties after mixing, physical properties after setting and biocompatibility. The tests of flow, film thickness, working time and setting time can be superseded by rheology as it details how MTA hydrates. Physical property tests should replicate physiological conditions, i.e. 37 °C and submerged in physiological solution. Biocompatibility tests should involve immediate placement of samples immediately after mixing rather than being cured prior to placement as this does not replicate clinical usage. Biocompatibility tests should seek to replicate physiological conditions with MTA tested immediately after mixing.

Classification and Nomenclature of Commercial Hygroscopic Dental Cements

Objective

Under the Global Medical Device Nomenclature (GMDN) system, the newly introduced term 'hygroscopic dental cement' (HDC) encompasses MTA as well as cements based on bioceramics, calcium silicate or calcium sulphate. Many HDCs have a long history of use in dentistry. There is a need for a consistent, logical and informed approach to the nomenclature of traditional and novel HDCs.

Methods

Commercial manufacturers of HDC were contacted requesting information on the compositions of products. Manufacturers that were unknown to the authors, that were unable to be contacted, that wished to be excluded from this paper, or that did not send their information on compositions in due time were not included.

Results

The compositions of commercial HDCs include various hybrids of calcium silicates, calcium aluminates, calcium phosphates, calcium sulphate as well as zinc sulphates. Furthermore, there are variations in the radiopacifier as well as additives that change the handling or setting processes.

Conclusion

The inclusion of different additives to HDCs enables variation in handling properties such that they now exist as distinct putties and sealers as well as cements.

Antimicrobial activity of ProRoot MTA in contact with blood

Dental materials based on Portland cement, which is used in the construction industry have gained popularity for clinical use due to their hydraulic properties, the interaction with tooth tissue and their antimicrobial properties. The antimicrobial properties are optimal in vitro. However in clinical use contact with blood may affect the antimicrobial properties. This study aims to assess whether antimicrobial properties of the Portland cement-based dental cements such as mineral trioxide aggregate (MTA) are also affected by contact with blood present in clinical situations. ProRoot MTA, a Portland cement-based dental cement was characterized following contact with water, or heparinized blood after 1 day and 7 days aging. The antimicrobial activity under the mentioned conditions was assessed using 3 antimicrobial tests: agar diffusion test, direct contact test and intratubular infection test. MTA in contact with blood was severely discoloured, exhibited an additional phosphorus peak in elemental analysis, no calcium hydroxide peaks and no areas of bacterial inhibition growth in the agar diffusion test were demonstrated. ProRoot MTA showed limited antimicrobial activity, in both the direct contact test and intratubular infection test. When aged in water ProRoot MTA showed higher antimicrobial activity than when aged in blood. Antimicrobial activity reduced significantly after 7 days. Further assessment is required to investigate behaviour in clinical situations.

Comparison of the Potential Discoloration Effect of Bioaggregate, Biodentine, and White Mineral Trioxide Aggregate on Bovine Teeth: In Vitro Research

INTRODUCTION

Tricalcium silicate cements can be used for pulp capping, pulpotomies, apical barrier formation in teeth with open apices, repair of root perforations, regenerative endodontics, and root canal filling. The aim of this study was to evaluate and compare the discoloration potential of 3 different tricalcium cements using a bovine tooth model.

METHODS

Forty bovine anterior teeth have been used for the study. Crowns separated from the roots were randomly divided into 4 groups: the BioAggregate (IBC, Vancouver, Canada) group, the Biodentine (Septodont, Saint Maur des Fosses, France) group, the mineral trioxide aggregate Angelus (Angelus, Londrina, PR, Brazil) group, and the only blood group. Materials have been placed to the standardized cavities on the lingual surfaces of the crowns, and their contact with blood has been provided. The color values of the samples were measured with a digital tooth shade determinator (VITA Easyshade; VITA Zahnfabrik, Bad Sackingen, Germany) before the placement of the materials, after the placement of the materials, in the 24th hour, in the first week, in the first month, in the third month, and in the first year. The mean value of all groups was compared using the Tukey multiple comparison test (α = 0.05).

RESULTS

All groups displayed increasing discoloration during a period of the first year. The "only blood group" showed the highest color change values, and it was followed as BioAggregate, mineral trioxide aggregate Angelus, and Biodentine, respectively. Statistically significant differences were found for Biodentine when compared with the only blood and BioAggregate groups (P < .05).

CONCLUSIONS

Considering the results of the study, Biodentine is found to have the least discoloration potential among the tested materials.

Assessment of the biocompatibility of mineral trioxide aggregate, bioaggregate, and biodentine in the subcutaneous tissue of rats

OBJECTIVE

The objective of this study was to evaluate the tissue inflammation caused by three endodontic repair materials.

MATERIALS AND METHODS

The materials included micro mega-mineral trioxide aggregate (MM-MTA), bioaggregate (BA), and biodentine (BD), which were implanted into the subcutaneous tissue of rats. The tissue samples for histological examination were prepared. The infiltration of lymphocytes and macrophages into the tissue was examined to assess the inflammatory response.

RESULTS

Lymphocyte infiltration: A significant increase was detected in the MM-MTA and BA groups on the 7th and 14th days as compared with the control (7th day P=0.0001, 14th day P=0.0176). There was no difference between the groups on the 45th day (P=0.1730). Lymphocyte infiltration had decreased over time in all groups. Macrophage infiltration: There was a significant increase by the 7th day in the test groups as compared to the control group (P=0.007). However, there was no difference between the experimental groups on the 14th (P=0.2708) and 45th (P=0.1291) days.

CONCLUSION

While MM-MTA and BA showed a similar biocompatibility, BD was more biocompatible than MM-MTA and BA in the 1 st week of the experiment. However, there was no difference between the materials at the end of the 45th day. MM-MTA, BA, and BD can be considered suitable endodontic repair materials.

Determination of trace elements in rat organs implanted with endodontic repair materials by ICP-MS

To investigate the levels of seven elements using an inductively coupled plasma-mass spectrometry (ICP-MS) method in rat organs after the implantation of Micro Mega Mineral Trioxide Aggregate (MM-MTA), Bioaggregate (BA) and Biodentine (BD) materials. MM-MTA, BA and BD were implanted into the subcutaneous tissue of 15 Wistar albino rats; three control animals had no operation. After 45 days, the rats were sacrificed and their brains, kidneys and livers were removed. The ICP-MS analysis was used to determine trace elements. Data were analysed using the Kruskal-Wallis and Connover post hoc tests. There was no significant difference between the control groups and the MM-MTA, BA and BD groups according to the concentration of aluminum, calcium, arsenic and lead in the rats' organs. Beryllium was not detected in all tissue samples. Chromium levels of these materials were higher than the control group in brain and kidney samples (P = 0.038 and P = 0.037); magnesium levels were higher than the control group in kidney and liver samples (P = 0.030 and P = 0.008). MM-MTA, BA and BD were nontoxic according to trace element levels in brain, kidney and liver samples of rats. Further investigation is required to understand the systemic effects of these materials.

Evaluation of reparative dentin formation of ProRoot MTA, Biodentine and BioAggregate using micro-CT and immunohistochemistry

Objectives

The purpose of this study was to assess the ability of two new calcium silicate-based pulp-capping materials (Biodentine and BioAggregate) to induce healing in a rat pulp injury model and to compare them with mineral trioxide aggregate (MTA).

Materials and Methods

Eighteen rats were anesthetized, cavities were prepared and the pulp was capped with either of ProRoot MTA, Biodentine, or BioAggregate. The specimens were scanned using a high-resolution micro-computed tomography (micro-CT) system and were prepared and evaluated histologically and immunohistochemically using dentin sialoprotein (DSP).

Results

On micro-CT analysis, the ProRoot MTA and Biodentine groups showed significantly thicker hard tissue formation (p < 0.05). On H&E staining, ProRoot MTA showed complete dentin bridge formation with normal pulpal histology. In the Biodentine and BioAggregate groups, a thick, homogeneous hard tissue barrier was observed. The ProRoot MTA specimens showed strong immunopositive reaction for DSP.

Conclusions

Our results suggest that calcium silicate-based pulp-capping materials induce favorable effects on reparative processes during vital pulp therapy and that both Biodentine and BioAggregate could be considered as alternatives to ProRoot MTA.

Comparison of the antimicrobial activity of direct pulp-capping materials: Mineral trioxide aggregate-Angelus and Biodentine

Purpose:

To compare the antimicrobial activity of the tricalcium silicate-based Biodentine (BD) and mineral trioxide aggregate (MTA)-Angelus cement with the aid of agar diffusion test.

Materials and Methods:

Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Enterococcus faecium were inoculated in the Brucella liquid medium and were incubated at 37°C for 24 h. Thereafter, 100 >μl of the liquid culture of bacteria inoculated in the Mueller-Hinton agar with spread plate technique. Petri plates were dried in room temperature. For every microorganism, 3 petri plates were prepared (12 in total). In the medium, in every petri plate, 2 holes with 5 mm diameter and 2 mm depth were made. Afterward, BD and MTA-Angelus were filled into these holes under aseptic conditions according to the instructions of the manufacturing company. Then, the plates were kept in the incubator at 37°C for 24 h, and the diameters of the inhibition zones were measured with a digital caliper.

Results:

Inhibition zones formed by BD against E. coli and S. aureus were significantly larger than the zones formed by MTA-Angelus (P < 0.05). However, the inhibition zones formed by MTA-Angelus against P. aureus and E. faecium were larger than the zones formed by BD (P < 0.05).

Conclusion:

Within the limits of the present study, tricalcium silicate-based MTA-Angelus and BD have antimicrobial activity against E. coli, S. aureus, P. aureus, and E. faecium.

Bifunctional bioceramics stimulating osteogenic differentiation of a gingival fibroblast and inhibiting plaque biofilm formation

A bifunctional Ca–Mg–Si bioceramic induces osteogenic differentiation of gingival fibroblasts and inhibits plaque biofilm formation.

Calcium silicate-based cements: composition, properties, and clinical applications

Mineral trioxide aggregate (MTA) is a calcium silicate-based cement (CSC) commonly used in endodontic procedures involving pulpal regeneration and hard tissue repair, such as pulp capping, pulpotomy, apexogenesis, apexification, perforation repair, and root-end filling. Despite the superior laboratory and clinical performance of MTA in comparison with previous endodontic repair cements, such as Ca(OH)₂ , MTA has poor handling properties and a long setting time. New CSC have been commercially launched and marketed to overcome the limitations of MTA. The aim of the present review was to explore the available literature on new CSC products, and to give evidence-based recommendations for the clinical use of these materials. Within the limitations of the available data in the literature regarding the properties and performance of the new CSC, the newer products could be promising alternatives to MTA; however, further research is required to support this assumption.

A Review on Perforation Repair Materials

Perforation is an artificial communication between the root canal system and supporting tissues of the teeth. Root perforation complicates the treatment and deprives the prognosis if not properly managed. A wide variety of materials to seal the perforations have been suggested in literature. There are many comparative studies showing the efficacy of one material over the other. Literature shows many reviews on diagnosis, treatment plan and factors affecting prognosis of perforation repair; but none of these articles elaborated upon various materials available to seal the perforation. The present article aims at describing all the materials used for perforation repair from the past till date; it also offers a literature review of all the articles published over last four decades referred to the treatment of perforation with various root repair materials.

Combined Antibacterial Effect of Sodium Hypochlorite and Root Canal Sealers against Enterococcus faecalis Biofilms in Dentin Canals

INTRODUCTION

The present study aimed to evaluate the antibacterial effect of the combined use of sodium hypochlorite (NaOCl) and root canal sealers on Enterococcus faecalis biofilms using a dentin infection model.

METHODS

Cells of E. faecalis were introduced into the dentinal tubules by centrifugation and incubated in brain-heart infusion for 3 weeks. The biofilms in dentin were first subjected to 5% NaOCl or sterile water for 10 minutes followed by an equal thickness of AH Plus (Dentsply International Inc, York, PA), Endosequence BC Sealer (Brasseler USA, Savannah, GA), or MTA Fillapex (Angelus Indústria de Produtos Odontológicos S/A, Londrina, Brazil) placed on the root canal wall of the dentin specimens for 7, 30, and 60 days. Gutta-percha and water were used in a similar manner as controls. The proportions of dead and live bacteria inside the dentinal tubules were assessed by confocal laser scanning microscopy and viability staining.

RESULTS

The combined use of NaOCl and sealers (30 and 60 days) killed significantly more bacteria than NaOCl or sealers alone (P < .05). NaOCl + MTA Fillapex was the most effective antibacterial combination by killing 83% bacteria in dentin tubules in 60 days. Thirty and 60 days of exposure to the sealers resulted in significantly more dead bacteria in dentin biofilms than 7-day exposures (P < .05).

CONCLUSIONS

The placement of root canal sealer after NaOCl treatment enhanced antibacterial effects against E. faecalis in the dentinal tubules. Little additional effect was obtained after 30 days of exposure to sealers.

An assessment of antibacterial activity of three pulp capping materials on Enterococcus faecalis by a direct contact test: An in vitro study

Objective:

The aim of this in vitro study was to evaluate antimicrobial activities of three different pulp capping materials; Biodentine, mineral trioxide aggregate (MTA) Angelus, and Dycal against Enterococcus faecalis and their durability with time.

Materials and Methods:

Direct contact test was used for the assessment. Three sets of sealers were mixed and placed on microtiter plate wells: One set was used within 20 min of recommended setting time while others were used after 24-h and 1-week. E. faecalis suspension was placed directly on the materials for 1 h and then transferred to another plate with fresh media. Nine wells of bacteria without the tested cements served as the positive control. One well of the tested cements without bacteria served as the negative control. Bacterial growth was evaluated by a temperature-controlled microplate spectrophotometer for 1-h intervals among 24 h. Data were analyzed using Kruskal–Wallis test.

Results:

All tested materials showed less bacterial density than the control group. MTA, Biodentine, and Dycal showed significantly higher bacterial density than the control group in freshly mixed samples (P < 0.05). And MTA showed significantly higher antibacterial activity than Dycal (P < 0.05). In 24 h, materials did not show any differences (P > 0.05). MTA and Biodentine samples showed significant differences than Dycal; MTA also showed higher antibacterial activity than control in 1-week samples (P < 0.05).

Conclusion:

While freshly mixed MTA showed the best antibacterial activity over time, Biodentine had shown similar antibacterial activity to MTA.

Effect of BioAggregate on Receptor Activator of Nuclear Factor-Kappa B Ligand-induced Osteoclastogenesis from Murine Macrophage Cell Line In Vitro

INTRODUCTION

This study aimed to investigate the effect of BioAggregate, a calcium silicate-based nanoparticulate bioceramic, on the regulation of receptor activator of nuclear factor-kappa B ligand (RANKL)-induced osteoclast differentiation and bone resorption in vitro, as well as to delineate the underlying molecular mechanism. The performance of BioAggregate was compared with that of ProRoot mineral trioxide aggregate (MTA).

METHODS

Cells of a murine macrophage cell line RAW 264.7 were treated with various concentrations of BioAggregate and MTA extracts. Cytotoxicity of material extracts was evaluated with Cell Counting Kit-8 assay. RANKL-induced osteoclast differentiation and function were assessed with tartrate-resistant acid phosphatase staining, F-actin staining, and lacunar resorption pits assay. The mRNA expression associated with osteoclast function was detected with quantitative real-time polymerase chain reaction. Related molecular signaling pathways were investigated with Western blot and immunofluorescence.

RESULTS

BioAggregate extracts dose-dependently inhibited RANKL-induced osteoclast formation and resorption capacity without evident cytotoxicity. RAW 264.7 cells exposed to BioAggregate extracts also presented a decrease in RANKL-stimulated mRNA expression of osteoclast-related genes and transcription factors. Moreover, cells treated with BioAggregate extracts exhibited attenuated TRAF6 expression, suppressed mitogen-activated protein kinase signaling, and decreased nuclear translocation of NFATc1 and c-Fos in the presence of RANKL. Comparable effects were induced by MTA.

CONCLUSIONS

BioAggregate and MTA exhibit comparable inhibitory effect on osteoclast differentiation and function in vitro, and our findings provide valuable insights into the mechanism of bioceramic-mediated anti-osteoclastogenic activity.

Effect of BioAggregate on osteoclast differentiation and inflammatory bone resorption in vivo

AIM

To investigate the effect of BioAggregate (Innovative Bioceramix, Vancouver, BC, Canada) on lipopolysaccharide (LPS)-induced bone destruction in vivo and to compare its performance with that of mineral trioxide aggregate (MTA; Dentsply Tulsa Dental, Tulsa, OK, USA).

METHODOLOGY

Mouse bone marrow macrophages (BMMs) were primary cultured and treated with several concentrations of BioAggregate and MTA extracts. Cell viability was measured with a Cell Counting Kit-8 assay, whilst in vitro osteoclast differentiation was evaluated with tartrate-resistant acid phosphatase (TRAP) staining. LPS-induced mouse calvarial bone destruction model was established to assess the effect of BioAggregate and MTA extracts in vivo. Mice were killed on day 7, and calvarial bones were prepared for microcomputed tomography scanning, histologic analysis and double-immunofluorescence staining. Statistical tests used were one-way anova followed by Student-Newman-Keuls test.

RESULTS

BioAggregate extracts displayed no obvious cytotoxicity to BMMs and significantly inhibited (P < 0.01) the differentiation of RANKL-stimulated BMMs. Comparable effects were induced by MTA. BioAggregate and MTA extracts markedly reduced (P < 0.01) osteoclast numbers and attenuated (P < 0.05) bone resorption in LPS-challenged mouse calvaria. The expression levels of osteoclastogenic cathepsin K and its upstream regulator nuclear factor of activated T-cell cytoplasmic 1 and c-Fos were also decreased by BioAggregate and MTA extracts.

CONCLUSIONS

BioAggregate and MTA showed comparable inhibitory effect on osteoclast differentiation and inflammatory bone resorption in vivo.

Resistance to leakage of various thicknesses of apical plugs of Bioaggregate using liquid filtration model

AIM

The aim of this study was to compare the resistance to leakage of different thicknesses of Bioaggregate (BA) and 4-mm-thick white mineral trioxide aggregate (WMTA) in an apexification model using liquid filtration.

METHODS

32 extracted mandibular premolar teeth were sectioned at the cemento-enamel junction and 3-4 mm from the tooth apex to obtain 12-mm-long root segments. The apical and coronal thirds were prepared with size two through six Gates Glidden burs. The teeth were divided into four groups according to material and thickness, as follows: Group 1: 2-mm BA; Group 2: 4-mm BA; Group 3: 12-mm (total length) BA; Group 4: 4-mm WMTA (control). The empty parts of the roots in Groups 1, 2, and 4 were filled with gutta-percha and root canal sealer, and leakage was measured using fluid filtration. The data were analyzed using the Kruskal-Wallis H-test.

RESULTS

No statistical differences in microleakage were observed between Groups 1, 2, and 4 (P > 0.05). Group 3 (roots filled completely with BA) showed significantly less leakage than the other groups tested (P < 0.01).

CONCLUSIONS

The findings of this study showed that 12 mm of BA exhibited the best resistance to leakage. At the same time, 2-4 mm of BA showed similar results when compared to 4-mm MTA. In light of these results, this study suggests that BA may be a good candidate for further clinical studies when used as an apical barrier for apexification.

Antibacterial activity of various root canal sealers and root-end filling materials in dentin blocks infected ex vivo with Enterococcus faecalis

OBJECTIVE

The aim was to investigate the antibacterial activity of the root-end filling materials MTA and IRM, different endodontic sealers and calcium hydroxide [Ca(OH)₂] in experimentally infected dentinal tubules.

MATERIALS AND METHODS

Ninety-four human root segments were prepared and the root canals were enlarged to ISO size 90. After smear removal, the specimens were infected with Enterococcus faecalis for 3 weeks. The roots were divided into eight groups and filled either with MTA, IRM, Ca(OH)₂, gutta-percha and EndoRez (ER)/GuttaFlow (GF)/AH Plus (AH+) or with Resilon and Epiphany (EpRe). One group of specimens was left unfilled for control. Half of the specimens were treated for 1 day and the other half for 7 days in humid conditions at 37°C. Dentin samples from each canal were collected by enlarging the canals to ISO size 150; thus a dentinal depth of 300 µm was sampled. The number of cultivable bacteria was determined for each specimen. Statistical significance was set to 5%.

RESULTS

After 1-day or 7-days of treatment, compared to control, all materials (except ER and GF at day 7) significantly reduced the number of bacteria. At day 1 and day 7, no significant difference was found between ER and GF and between Ca(OH)₂, AH+, EpRe, IRM and MTA. However, a significant difference was found between these two groups of materials (except between GF and EpRe at day 7). Significantly more bacteria were cultured in the ER, GF, EpRe and IRM groups at day 7 compared to day 1.

CONCLUSIONS

All materials exerted varying degrees of antibacterial activity which generally tended to decrease with time. The most stable antibacterial effect throughout the 7-day period was for Ca(OH)₂, AH+ and MTA.