Comparison of the biocompatibility of calcium silicate-based materials to mineral trioxide aggregate: Systematic review

Biological, Biomechanical, and Histopathological Evaluation of Polyetherketoneketone Bioactive Composite as Implant Material

While polyetherketoneketone is a high-performance thermoplastic polymer, its hydrophobicity and inertness limit bone adhesion. This study aimed to evaluate a novel PEKK/CaSiO3/TeO2 nanocomposite, comparing it to PEKK/15 wt.% CaSiO3 and PEKK groups. The in vitro study, involving 90 discs (n = 30), assessed the cytotoxicity of all groups after 24, 72, and 168 h. The in vivo animal study, using cylinder-type implants (n = 30), evaluated osseointegration through biomechanical push-out tests, descriptive histopathological examinations of decalcified sections stained with hematoxylin and eosin, and histomorphometric analysis of new bone formation area after 2- and 6-week healing intervals. The cytocompatibility of PEKK/15 wt.% CaSiO3/1 wt.% TeO2 composite confirmed its acceptance as a biomedical material. Additionally, in vivo study results showed that the PEKK/15 wt.% CaSiO3/1 wt.% TeO2 had the highest shear strength value and the highest new bone formation area compared to other experimental groups. The multimodal concept of adding CaSiO3 micro fillers and TeO2 nanofillers to PEKK produces a cytocompatible composite that enhances osseointegration and new bone formation in a rabbit's femur after 2- and 6-week healing intervals.

In vitro Analysis of DSPP and BSP Expression: Comparing the Odontogenic Influence of Bio-C Repair and Biodentine in hDPSCs

OBJECTIVES

 This study compared the ability of BIO-C Repair (BC) and Biodentine (BD) in relation to odontogenic differentiation by evaluating the dentin sialophosphoprotein (DSPP) and bone sialoprotein (BSP) expression and mineral deposition of human dental pulp stem cells (hDPSCs).

MATERIALS AND METHODS

 BC and BD were pulverized and sterilized (ISO 10993-5:2009). The hDPSCs were the result of primary cultures that were 80% confluent (having gone through the stem cell marker tests CD90 98%, CD105 99.7%, CD73 94%, and LinNeg 0.5%) and reached P2-3 by means of serum starvation for 24 hours. This study involved seven groups, in which the hDPSCs were cultured on osteogenic media with the addition of either BD (Septodont, United States) at concentrations of 1:1, 1:2, or 1:5; BC (Angelus, Brazil) at concentrations of 1:1, 1:2, or 1:5; or the negative control (Dulbecco's modified eagle medium + osteogenic media). The hDPSC differentiation was determined via enzyme-linked immunosorbent assays of DSPP and BSP expression performed on days 7 and 14 and alizarin red staining performed on day 21.

STATISTICAL ANALYSIS

 The data were analyzed using a one-way analysis of variance, followed by Tamhane's post hoc test, to compare the differences between groups. The t-test dependent was also used to identify differences between groups.

RESULTS

 BC and BD at 1:1 concentration, there was a statistically significant difference in DSPP and BSP expression. However, at concentrations of 1:2 and 1:5, there was no significant difference observed in either duration of observation (p > 0.05). The highest DSPP and BSP concentrations after 7 and 14 days of observation were observed with BD and BC at 1:5 concentration (6.6-6.71 and 13.20-13.47 ng/mL).

CONCLUSION

 The study shows that BC is as effective as BD in enhancing DSPP and BSP expression and mineral deposition in hDPSCs. The 1:5 concentration of BC showed the highest levels of DSPP and BSP expression and mineral deposition.

Physical, chemical and biological properties of MTA Angelus and novel AGM MTA: an in vitro analysis

INTRODUCTION

Mineral trioxide aggregate (MTA) is a calcium silicate-based cement that has changed conventional dental therapeutic approaches. This study aimed to evaluate physical, chemical and biological properties of novel AGM MTA, in comparison with MTA Angelus.

METHODS

The samples were prepared according to the manufacturer's instructions. The initial and final setting times were measured via a Gillmore needle following the ISO 6876:2012 standard. The radiopacity of the materials was evaluated against an aluminium step wedge on the basis of the ISO 6876 and 13,116 standards. The pH changes were measured at intervals of 3, 6, 24, 72, 96 and 144 h postimmersion in Hank's solution and calcium ion release was analysed after 168 h of immersion via inductively coupled plasma optical emission spectroscopy (ICP‒OES). Moreover, the cytotoxicity was assessed through the MTT assay on human dental pulp stem cells (hDPSCs) after 24 and 72 h of exposure to the set/fresh status of various dilutions of MTA extracts, following the ISO 10993-12 standard.

RESULTS

No significant difference was found between the initial setting times of the two materials (Angelus: 11.0 ± 1.0 min, AGM: 10.3 ± 1.5 min); however, MTA Angelus demonstrated a significantly shorter final setting time. Both materials met the minimum radiopacity requirements according to the ISO 6876 standard, with MTA Angelus exhibiting greater radiopacity than AGM MTA. Both materials created an alkaline environment without presenting any differences in each time point and AGM MTA released significantly greater amounts of calcium ions. In the cytotoxicity assessment, while the diluted extracts of both materials did not elicit any cytotoxic effects, the nondiluted samples, after 72 h of exposure, as well as the 30-min set AGM MTA after 24 h of exposure, were shown to be cytotoxic.

CONCLUSIONS

In conclusion, MTA Angelus presented a faster setting time and lower cytotoxicity, while AGM MTA demonstrated greater calcium ion release. However, both materials presented clinically acceptable properties and AGM MTA could be a potential alternative to MTA Angelus. However, further clinical studies are required to confirm its application.

Enhancing the Physical, Antimicrobial, and Osteo/Odontogenic Properties of a Sol-Gel-Derived Tricalcium Silicate by Graphene Oxide for Vital Pulp Therapies

OBJECTIVES

This study developed a sol-gel tricalcium silicate/graphene oxide (TCS-GO) composite and examined its physicochemical properties, antimicrobial activity, and osteo/odontogenic effect on dental pulp stem cells.

METHODS

Tricalcium silicate was synthesized and combined with graphene oxide at three different concentrations, namely 0.02%, 0.04%, and 0.08% w/w, while tricalcium silicate and mineral trioxide aggregate served as controls. The setting time, compressive strength, pH, and calcium ion release of the composites were evaluated, as well as antimicrobial properties against Streptococcus mutans and Lactobacillus acidophilus. Additionally, the viability of dental pulp stem cells; apatite forming ability; and the gene expression of Alkaline phosphatase, Dentin sialophosphoprotein, and Runt-related transcription factor 2 were assessed.

RESULTS

TCS-GO (0.08%) showed a significantly shorter setting time and higher compressive strength when compared to MTA (p < 0.05). Additionally, tricalcium silicate and TCS-GO groups showed a higher release of Ca ions than MTA, with no significant difference in pH values among the different groups. TCS-GO (0.08%) also demonstrated a significantly stronger antimicrobial effect against Lactobacillus acidophilus compared to MTA (p < 0.05). ALP expression was higher in TCS-GO (0.08%) than MTA on days 3 and 7, while DSPP expression was higher in TCS-GO (0.08%) than MTA on day 3 but reversed on day 7. There was no significant difference in RUNX2 expression between TCS-GO (0.08%) and MTA on days 3 and 7.

CONCLUSIONS

The TCS-GO (0.08%) composite demonstrated superior physicochemical characteristics and antimicrobial properties compared to MTA. Moreover, the early upregulation of ALP and DSPP markers in TCS-GO (0.08%) indicates that it has the potential to promote and enhance the osteo/odontogenic differentiation of DPSCs.

Effect of radiopacifier and liquid in the physicochemical and biological properties of calcium silicate clinker Angelus: A laboratory investigation

The aim of this study was to evaluate the effect of radiopacifier calcium tungstate and manipulation with distilled water (DW) or liquid with additives (LA) on calcium silicate clinker Angelus (CL) properties, compared with MTA (Angelus, Brazil) and MTA Repair HP (MTAHP, Angelus, Brazil). The physicochemical properties, cellular viability and bioactivity were evaluated. ANOVA/Tukey and Bonferroni tests were performed (α = 0.05). There was no difference in material setting time (p > 0.05). MTA and MTAHP were similar (p > 0.05) and had greater radiopacity than CL + DW and CL + LA (p < 0.05). All experimental materials showed mass increase, alkalinisation capacity, besides biocompatibility and bioactivity at 3 and 7 days. The different liquids had no influence in the biological properties and bioactivity of the calcium silicate clinker Angelus. Calcium tungstate provided radiopacity, without changing the setting time, maintaining the mass increase and alkalinisation ability of the calcium silicate materials.

Bioceramic versus traditional biomaterials for endodontic sealers according to the ideal properties

Odontology, as a scientific discipline, continuously collaborates with biomaterials engineering to enhance treatment characteristics and patients' satisfaction. Endodontics, a specialized field of dentistry, focuses on the study, diagnosis, prevention, and treatment of dental disorders affecting the dental pulp, root, and surrounding tissues. A critical aspect of endodontic treatment involves the careful selection of an appropriate endodontic sealer for clinical use, as it significantly influences treatment outcomes. Traditional sealers, such as zinc oxide-eugenol, fatty acid, salicylate, epoxy resin, silicone, and methacrylate resin systems, have been extensively used for decades. However, advancements in endodontics have given rise to bioceramic-based sealers, offering improved properties and addressing new challenges in endodontic therapy. In this review, a classification of these materials and their ideal properties are presented to provide evidence-based guidance to clinicians. Physicochemical properties, including sealing ability, stability over time and space, as well as biological properties such as biocompatibility and antibacterial characteristics, along with cost-effectiveness, are essential factors influencing clinicians' decisions based on individual patient evaluations.

Effect of Different Root Canal Drying Protocols on the Bond Strength of Two Bioceramic Sealers

OBJECTIVES

 This study evaluated in vitro the effect of two different drying protocols on the dentin bond strength of two different bioceramic sealers (Sealer Plus BC [SP] and Bio C Sealer [BCS]). Bond strength and failure mode were evaluated according to the sealer, drying protocol, and root canal third.

MATERIALS AND METHODS

 Sixty extracted human mandibular single-rooted premolars were selected after anatomical standardization. The crowns were sectioned and root canals were prepared. Roots were randomly divided into four groups (n = 15 each). Each group was assigned a combination of one of the evaluated sealers (SP or BCS) and one of the drying protocols: canals dried with paper points (PP) or irrigation with saline followed by aspiration with silicon cannulas (IA). Obturations were performed using a single-cone technique. The teeth were temporized and stored for 7 days (100% humidity, 37°C). Roots were cut to obtain 2 mm thick discs for each third (coronal, middle, and apical). Push-out tests were performed on a universal testing machine, and the bond strength (MPa) of each specimen was calculated by dividing the load (N) by the interface area. Failure type was assessed under ×4 magnification.

STATISTICAL ANALYSIS

 Data were statistically analyzed with a significance set at 5%. An analysis of variance test followed by the Games-Howell post-hoc test was used to compare the mean values between the groups and the interaction of the variables.

RESULTS

 The predominant failure type was cohesive, followed by mixed failure and adhesive in all groups. The apical third presented the highest bond strength (p < 0.05) regardless of the group, followed by the middle and coronal thirds. Overall, the SP PP group had the highest mean bond strength (p < 0.01), but the SP sealer was negatively affected by the IA drying protocol in the coronal and middle thirds. The BCS presented similar results within the third stage, regardless of the drying protocol.

CONCLUSIONS

 Sealer Plus BC had a higher bond strength than Bio C Sealer, but it was negatively affected by the irrigation-aspiration protocol in the coronal and middle thirds. For the apical third, there was no difference between the groups; thus, a similar bond strength was observed regardless of the drying protocol or sealer.

Surface Modification of Titanium Implants by Metal Ions and Nanoparticles for Biomedical Application

Implant surface modification can improve osseointegration and reduce peri-implant inflammation. Implant surfaces are modified with metals because of their excellent mechanical properties and significant functions. Metal surface modification is divided into metal ions and nanoparticle surface modification. These two methods function by adding a finishing metal to the surface of the implant, and both play a role in promoting osteogenic, angiogenic, and antibacterial properties. Based on this, the nanostructural surface changes confer stronger antibacterial and cellular affinity to the implant surface. The current paper reviews the forms, mechanisms, and applications of nanoparticles and metal ion modifications to provide a foundation for the surface modification of implants.

Sol-gel synthesis of lithium doped mesoporous bioactive glass nanoparticles and tricalcium silicate for restorative dentistry: Comparative investigation of physico-chemical structure, antibacterial susceptibility and biocompatibility

Introduction: The sol-gel method for production of mesoporous bioactive glass nanoparticles (MBGNs) has been adapted to synthesize tricalcium silicate (TCS) particles which, when formulated with other additives, form the gold standard for dentine-pulp complex regeneration. Comparison of TCS and MBGNs obtained by sol-gel method is critical considering the results of the first ever clinical trials of sol-gel BAG as pulpotomy materials in children. Moreover, although lithium (Li) based glass ceramics have been long used as dental prostheses materials, doping of Li ion into MBGNs for targeted dental applications is yet to be investigated. The fact that lithium chloride benefits pulp regeneration in vitro also makes this a worthwhile undertaking. Therefore, this study aimed to synthesize TCS and MBGNs doped with Li by sol-gel method, and perform comparative characterizations of the obtained particles.

Methods: TCS particles and MBGNs containing 0%, 5%, 10% and 20% Li were synthesized and particle morphology and chemical structure determined. Powder concentrations of 15mg/10 mL were incubated in artificial saliva (AS), Hank’s balanced saline solution (HBSS) and simulated body fluid (SBF), at 37°C for 28 days and pH evolution and apatite formation, monitored. Bactericidal effects against S. aureus and E. coli, as well as possible cytotoxicity against MG63 cells were also evaluated through turbidity measurements.

Results: MBGNs were confirmed to be mesoporous spheres ranging in size from 123 nm to 194 nm, while TCS formed irregular nano-structured agglomerates whose size was generally larger and variable. From ICP-OES data, extremely low Li ion incorporation into MBGNs was detected. All particles had an alkalinizing effect on all immersion media, but TCS elevated pH the most. SBF resulted in apatite formation for all particle types as early as 3 days, but TCS appears to be the only particle to form apatite in AS at a similar period. Although all particles had an effect on both bacteria, this was pronounced for undoped MBGNs. Whereas all particles are biocompatible, MBGNs showed better antimicrobial properties while TCS particles were associated with greater bioactivity.

Conclusion: Synergizing these effects in dental biomaterials may be a worthwhile undertaking and realistic data on bioactive compounds targeting dental application may be obtained by varying the immersion media.

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.

Discoloration Improvement by Mechanically-Milled Binary Oxides as Radiopacifier for Mineral Trioxide Aggregates

Mineral trioxide aggregates (MTA) have been widely used in endodontic treatments, but after some time, patients suffer tooth discoloration due to the use of bismuth oxide (Bi2O3) as a radiopacifier. Replacement of Bi2O3 with high energy ball-milled single (zirconia ZrO2; hafnia, HfO2; or tantalum pentoxide, Ta2O5) or binary oxide powder was attempted, and corresponding discoloration improvement was investigated in the present study. Bi2O3-free MTA is expected to exhibit superior discoloration. The radiopacity, diametral tensile strength, and discoloration of MTA-like cements prepared from the as-milled powder were investigated. Experimental results showed that MTA-like cements prepared using Ta2O5 exhibited a slightly higher radiopacity than that of HfO2 but had a much higher radiopacity than ZrO2. Milling treatment (30 min to 3 h) did not affect the radiopacities significantly. These MTA-like cements exhibited superior color stability (all measured ΔE00 < 1.0) without any perceptible differences after UV irradiation. MTA-like cements prepared using ZrO2 exhibited the best color stability but the lowest radiopacity, which can be improved by introducing binary oxide. Among the investigated samples, MTA-like cement using (ZrO2)50(Ta2O5)50 exhibited excellent color stability and the best overall performance with a radiopacity of 3.25 mmAl and a diametral tensile strength of 4.39 MPa.

Alkalizing Properties of Six Calcium-Silicate Endodontic Biomaterials

INTRODUCTION

Calcium silicate-based cements (CSC), are self-setting hydraulic biomaterials widely used for reparative procedures in dentistry and endodontics. These materials possess physical properties, such as ion release, porosity, solubility, and radiopacity. Their biological properties are connected to their alkalizing activity and calcium release capacity.

MATERIALS AND METHODS

Six calcium silicate-based materials were selected for this study: TheraCal LC (Bisco Inc., Schaumburg, IL, USA), MTA Plus (PrevestDenpro, Jammu, India Avalon Biomed Inc., Bradenton, FL, USA), Biodentine (Septodont, Saint-Maur-des-Fossés, France), RetroMTA (BioMTA, Seoul, Korea), MTA Flow (Ultradent Products, Inc., South Jordan, UT, USA), and OrthoMTA (BioMTA, Seoul, Korea). The pH was analyzed immediately after immersion (baseline) and after 1 h, 3 h, 1 day, 2 days, 3 days, 1 week, 2 weeks, 3 weeks, and 1 year with a pH meter, previously calibrated with solutions of known pH. All testing materials had alkaline pH.

RESULTS

Analysis of the tested materials showed statistically significant differences in terms of pH changes as a function of the time showed a gradual rise in the pH of all materials.

CONCLUSIONS

All tested materials exhibited continuous hydroxyl ion release resulting in a rise in pH until the end of time of experience.

Characterization, Physical Properties, and Biocompatibility of Novel Tricalcium Silicate-Chitosan Endodontic Sealer

OBJECTIVE

 The purpose of this study was to compare the characteristics, physical properties, and biocompatibility of the novel tricalcium silicate-chitosan (TCS-C) sealer with AH Plus and Sure-Seal Root.

MATERIALS AND METHODS

 The TCS-C powder was prepared by mixing tricalcium silicate with 2% water-soluble chitosan at a 5:1 ratio, followed by sufficient addition of 10 g/mL ratio of double-distilled water to form a homogeneous cement. Material characterizations (the Fourier Transform InfraRed [FTIR] and X-ray diffraction [XRD]), physical property investigations (flow and film thickness), and cytotoxicity tests in 3T3 mouse embryo fibroblast cell (MTT assay method) were performed on sealers, and the results were compared with those of the commercial products.

STATISTICAL ANALYSIS

 Statistical analysis was performed on flow and film thickness. The normality of the data was tested using the Shapiro-Wilk test. Statistical analysis was performed with one-way analysis of variance (ANOVA). The level of significance was set at p < 0.05.

RESULTS

 The TCS-C showed a mean flow of 31.98 ± 0.68 mm, compared with Sure Seal Root at 26.38 ± 0.69 mm and AH Plus at 26.50 ± 0.12 mm. The TCS-C showed a mean film thickness of 60 ± 10.0 mm compared with Sure-Seal Root at 50 ± 10.0 mm and AH Plus at 40 ± 15.8 mm. The TCS-C exhibited low to no cytotoxicity in fibroblast cell at all concentrations and exposure times.

CONCLUSION

 Adding water-soluble chitosan may improve the physical and biologic properties of tricalcium silicate cement. The novel TCS-C sealer did not fully meet the physical properties of an endodontic sealer, but it was not cytotoxic to fibroblast cells.

Physicochemical Properties and Inductive Effect of Calcium Strontium Silicate on the Differentiation of Human Dental Pulp Stem Cells for Vital Pulp Therapies: An In Vitro Study

The development of biomaterials that exhibit profound bioactivity and stimulate stem cell differentiation is imperative for the success and prognosis of vital pulp therapies. The objectives were to (1) synthesize calcium strontium silicate (CSR) ceramic through the sol−gel process (2) investigate its physicochemical properties, bioactivity, cytocompatibility, and its stimulatory effect on the differentiation of human dental pulp stem cells (HDPSC). Calcium silicate (CS) and calcium strontium silicate (CSR) were synthesized by the sol−gel method and characterized by x-ray diffraction (XRD). Setting time, compressive strength, and pH were measured. The in vitro apatite formation was evaluated by SEM-EDX and FTIR. The NIH/3T3 cell viability was assessed using an MTT assay. The differentiation of HDPSC was evaluated using alkaline phosphatase activity (ALP), and Alizarin red staining (ARS). Ion release of Ca, Sr, and Si was measured using inductive coupled plasma optical emission spectroscopy (ICP-OES). XRD showed the synthesis of (CaSrSiO4). The initial and final setting times were significantly shorter in CSR (5 ± 0.75 min, 29 ± 1.9 min) than in CS (8 ± 0.77 min, 31 ± 1.39 min), respectively (p < 0.05). No significant difference in compressive strength was found between CS and CSR (p > 0.05). CSR demonstrated higher apatite formation and cell viability than CS. The ALP activity was significantly higher in CSR 1.16 ± 0.12 than CS 0.92 ± 0.15 after 14 d of culture (p < 0.05). ARS showed higher mineralization in CSR than CS after 14 and 21 d culture times. CSR revealed enhanced differentiation of HDPSC, physicochemical properties, and bioactivity compared to CS.

Comparative evaluation of the effect of cold ceramic and MTA-Angelus on cell viability, attachment and differentiation of dental pulp stem cells and periodontal ligament fibroblasts: an in vitro study

BACKGROUND

Biocompatibility and induction of mineralized tissue formation are the properties expected from a material used in vital pulp therapy and repair of perforations. Cold ceramic (SJM, Iran; CC) is a newly introduced calcium silicate-based cement for above mentioned therapeutic applications. This in-vitro study aimed to compare the effect of CC and White MTA-Angelus (MTA) on cell viability, attachment, odontogenic differentiation, and calcification potential of human dental pulp stem cells (DPSCs) and periodontal ligament fibroblasts (PDLFs).

METHODS

Cell viability of DPSCs and PDLFs was assessed using MTT on days 1, 3, 7, and 14 (n = 9) in contact with freshly mixed and set states of CC and MTA. Field emission scanning electron micrographs (FESEM) were taken to evaluate cell-bioceramic interaction (n = 6). Gene expression levels of osteo/odontogenic markers (Dentin sialophosphoprotein, Dentin matrix protein 1, Collagen type I alpha 1, and Alkaline phosphatase (DSPP, DMP1, COL 1A1, and ALP, respectively) (n = 8) were assessed using qrt-PCR. ALP enzymatic activity was evaluated to assess the mineralization potential. A two-way ANOVA test was applied, and p < 0.05 was considered to be statistically significant.

RESULTS

The effect of freshly mixed and set MTA and CC on the survival of DPSCs and PDLFs in all study groups was statistically similar and comparable to the positive control group (p > 0.05); the only exception was for the viability of PDLFs in contact with freshly mixed cements on day 1, showing a more significant cytotoxic effect compared to the control and the set state of materials (p < 0.05). PDLFs attached well on CC and MTA. The spread and pseudopodium formation of the cells increased on both samples from day 1 to day 14. Contact of MTA and CC with DPSCs similarly increased expression of all dentinogenesis markers studied on days 7 and 14 compared to the control group (p < 0.001), except for DSPP expression on day 7 (p = 0.46 and p = 0.99 for MTA and CC, respectively).

CONCLUSIONS

Within the limitation of this in-vitro study, cold ceramic and MTA-Angelus showed high biocompatibility and induced increased expression of osteo/dentinogenic markers. Therefore, cold ceramic can be a suitable material for vital pulp therapy and the repair of root perforations.

Outcome of Periapical Surgery in Molars: A Retrospective Analysis of 424 Teeth

INTRODUCTION

The objective of this retrospective study was to assess the outcome of periapical surgery in a large number of molars in order to identify possible variables that might affect the outcome.

METHODS

The healing outcome of patients undergoing periapical surgery of molars from October 1999 to October 2019 was retrospectively evaluated. Outcome was dichotomized into "healed" and "nonhealed" using well-established clinical and radiographic healing criteria. The potential influence of patient-, tooth-, and treatment-related parameters on the healing outcome was analyzed.

RESULTS

A total of 424 molars in the same number of patients (45.5% male and 54.5% female) were evaluated. Three hundred seventy-two molars were classified as healed (87.7%). Three significant outcome predictors were identified: 1-year follow-up versus >1-5 years, >5-10 years, and >10 years (95.3% vs 82.2%, 76.3%, and 76.5% healed, respectively; P < .0001); root end filling material with bioceramic root repair material versus mineral trioxide aggregate (96.9% vs. 86.3% healed, respectively; P = .001); and preoperative evaluation based on cone-beam computed tomographic imaging versus 2-dimensional radiography (90.2% vs 81.4% healed, respectively; P = .02). Sex, age, tooth location, type of restoration, attachment level, presence of a post, quality of the root canal filling, technique of root end preparation, administration of antibiotics, and type of surgery had no significant impact on the healing outcome.

CONCLUSIONS

The healed rate for the concave (Retroplast) and cavity (mineral trioxide aggregate, SuperEBA [Staident International, Staines, UK], and bioceramic root repair material) root end preparation technique over all follow-up periods was 84% and 88.5%, respectively. The follow-up period, root end filling material, and preoperative evaluation based on cone-beam computed tomographic imaging had a significant influence on the healing outcome.

The Osteogenic Assessment of Mineral Trioxide Aggregate-based Endodontic Sealers in an Organotypic Ex Vivo Bone Development Model

INTRODUCTION

Mineral trioxide aggregate (MTA)-based sealers are endodontic materials with widespread success in distinct clinical applications, potentially embracing direct contact with the bone tissue. Bone response to these materials has been traditionally addressed in vitro. Nonetheless, translational data are limited by the absence of native cell-to-cell and cell-to-matrix interactions that hinder the representativeness of the analysis. Ex vivo organotypic systems, relying on the culture of explanted biological tissues, preserve the cell/tissue composition, reproducing the spatial and organizational in situ complexity. This study was grounded on an innovative research approach, relying on the assessment of an ex vivo organotypic bone tissue culture system to address the osteogenic response to 3 distinct MTA-based sealers.

METHODS

Embryonic chick femurs were isolated and grown ex vivo for 11 days in the presence of MTA Plus (Avalon Biomed Inc, Bradenton, FL), ProRoot MTA (Dentsply Tulsa Dental, Hohnson City, Germany), Biodentine (Septodont, Saint Maurdes Fosses, France), or AH Plus (Dentsply Sirona, Konstanz, Germany); the latter was used as a control material. Femurs were characterized by histologic, histochemical, and histomorphometric analysis. Gene expression assessment of relevant osteogenic markers was conducted by quantitative polymerase chain reaction.

RESULTS

All MTA-based sealers presented an enhanced osteogenic performance compared with AH Plus. Histochemical and histomorphometric analyses support the increased activation of the osteogenic program by MTA-based sealers, with enhanced collagenous matrix deposition and tissue mineralization. Gene expression analysis supported the enhanced activation of the osteogenic program. Comparatively, ProRoot MTA induced the highest osteogenic functionality on the characterized femurs.

CONCLUSIONS

MTA-based sealers enhanced the osteogenic activity within the assayed organotypic bone model, which was found to be a sensitive system for the assessment of osteogenic modulation mediated by endodontic sealers.

Recent update on potential cytotoxicity, biocompatibility and preventive measures of biomaterials used in dentistry

Dental treatment is provided for a wide variety of oral health problems like dental caries, periodontal diseases, periapical infections, replacement of missing teeth and orthodontic problems. Various biomaterials, like composite resins, amalgam, glass ionomer cement, acrylic resins, metal alloys, impression materials, bone grafts, membranes, local anaesthetics, etc., are used for dental applications. The physical and chemical characteristics of these materials influence the outcome of dental treatment. It also impacts on the biological, allergic and toxic potential of biomaterials. With innovations in science and their positive results, there is also a need for awareness about the biological risks of these biomaterials. The aim of dental treatment is to have effective, yet safe, and long-lasting results for the benefit of patients. For this, it is important to have a thorough understanding of biomaterials and their effects on local and systemic health. Materials used in dentistry undergo a series of analyses before their oral applications. To the best of our knowledge, this is the first and original review that discusses the reasons for and studies on the toxicity of commonly used biomaterials for applications in dentistry. It will help clinicians to formulate a methodical approach for the selection of dental biomaterials, thus providing an awareness for forecasting their risk of toxic reactions.

In vivo Biocompatibility and Bioactivity of Calcium Silicate-Based Bioceramics in Endodontics

Endodontic therapy aims to preserve or repair the activity and function of pulp and periapical tissues. Due to their excellent biological features, a substantial number of calcium silicate-based bioceramics have been introduced into endodontics and simultaneously increased the success rate of endodontic treatment. The present manuscript describes the in vivo biocompatibility and bioactivity of four types of calcium silicate-based bioceramics in endodontics.

Mineral Trioxide Aggregate Applications in Endodontics: A Review

A current topic in dentistry concerns the biocompatibility of the materials, and in particular, conservative dentistry and endodontics ones. The mineral trioxide aggregate (MTA) is a dental material with biocompatibility properties to oral and dental tissues. MTA was developed for dental root repair in endodontic treatment and it is formulated from commercial Portland cement, combined with bismuth oxide powder for radiopacity. MTA is used for creating apical plugs during apexification, repairing root perforations during root canal therapy, treating internal root resorption, and pulp capping. The objective of this article is to investigate MTA features from a clinical point of view, even compared with other biomaterials. All the clinical data regarding this dental material will be evaluated in this review article. Data obtained from the analysis of the past 10 years' literature highlighted 19 articles in which the MTA clinical aspects could be recorded. The results obtained in this article are an important step to demonstrate the safety and predictability of oral rehabilitations with these biomaterials and to promote a line to improve their properties in the future.

A biomimetic antitumor nanovaccine based on biocompatible calcium pyrophosphate and tumor cell membrane antigens

Currently, the cancer immunotherapy has made great progress while antitumor vaccine attracts substantial attention. Still, the selection of adjuvants as well as antigens are always the most crucial issues for better vaccination. In this study, we proposed a biomimetic antitumor nanovaccine based on biocompatible nanocarriers and tumor cell membrane antigens. Briefly, endogenous calcium pyrophosphate nanogranules with possible immune potentiating effect are designed and engineered, both as delivery vehicles and adjuvants. Then, these nanocarriers are coated with lipids and B16-OVA tumor cell membranes, so the biomembrane proteins can serve as tumor-specific antigens. It was found that calcium pyrophosphate nanogranules themselves were compatible and possessed adjuvant effect, while membrane proteins including tumor associated antigen were transferred onto the nanocarriers. It was demonstrated that such a biomimetic nanovaccine could be well endocytosed by dendritic cells, promote their maturation and antigen-presentation, facilitate lymph retention, and trigger obvious immune response. It was confirmed that the biomimetic vaccine could induce strong T-cell response, exhibit excellent tumor therapy and prophylactic effects, and simultaneously possess nice biocompatibility. In general, the present investigation might provide insights for the further design and application of antitumor vaccines.

A Microstructure Insight of MTA Repair HP of Rapid Setting Capacity and Bioactive Response

Mineral trioxide aggregate (MTA) is considered a bioactive endodontic material, which promotes natural mineralization at the material-tooth tissue interface. MTA Repair HP stands out because of the short setting time and the quick and effective bioactive response in vitro. The bioactivity, depens on material composition and microstructure. This work is devoted to analyze MTA Repair HP microstructural features, of both the powder precursor and set material, to get insights into the material physicochemical parameters—functionality performance relationships. Transmission electron microscopy (TEM), and field emission gun scanning electron microscopy (FEG-SEM) coupled with energy-dispersive X-ray (EDX) analyses were performed. X-ray diffraction (XRD) measurements were carried out at different times to investigate setting process. Bioactivity evaluation in vitro was carried out by soaking the processed cement disk in simulated body fluid (SBF). The presented results point out those MTA Repair HP precursor material characteristics of tricalcium silicate particles of nanometric size and high aspect ratio, which provide an elevated surface area and maximized components dispersion of calcium silicate and very reactive calcium aluminate. The MTA Repair HP precursor powder nanostructure and formulation, allows a hydration process comprising silicate hydrate structures, which are very effective to achieve both fast setting and efficient bioactive response.

Biocompatibility of Root Canal Sealers: A Systematic Review of In Vitro and In Vivo Studies

(1) Aim: To perform a systematic review of the literature on the biocompatibility of root canal sealers that encompasses the various types of sealers that are commercially available as well as both in vitro and in vivo evidence. (2) Methods: This systematic review has been registered in PROSPERO (ID 140445) and was carried out according to PRISMA guidelines using the following databases: PubMed, Cochrane Library, ClinicalTrials.gov, Science Direct, and Web of Science Core Collection. Studies published between 2000 and 11 June 2019 that evaluated cytotoxicity (cell viability/proliferation) and biocompatibility (tissue response) of root canal sealers were included. (3) Results: From a total of 1249 studies, 73 in vitro and 21 in vivo studies were included. In general, studies suggest that root canal sealers elicit mild to severe toxic effects and that several factors may influence biocompatibility, e.g., material setting condition and time, material concentration, and type of exposure. Bioactive endodontic sealers seem to exhibit a lower toxic potential in vitro. (4) Conclusions: The available evidence shows that root canal sealers exhibit variable toxic potential at the cellular and tissue level. However, the methodological heterogeneity among studies included in this systematic review and the somewhat conflicting results do not allow a conclusion on which type of sealer presents higher biocompatibility. Further research is crucial to achieve a better understanding of the biological effects of root canal sealers.

Biocompatibility and Mineralization Activity of Three Calcium Silicate-Based Root Canal Sealers Compared to Conventional Resin-Based Sealer in Human Dental Pulp Stem Cells

The purpose of this study was to compare the cytotoxic effects and mineralization activity of three calcium silicate-based root canal sealers to those of a conventional resin-based sealer. Experiments were performed using human dental pulp stem cells grown in a monolayer culture. The root canal sealers tested in this study were EndoSequence BC Sealer (Brasseler), BioRoot RCS (Septodont), Endoseal MTA (Maruchi), and AH Plus (Dentsply DeTrey). Experimental disks 6 mm in diameter and 3 mm in height were made and stored in a 100% humidity chamber at 37 °C for 72 h to achieve setting. The cytotoxicity of various root canal sealers was evaluated using a methyl-thiazoldiphenyl-tetrazolium (MTT) assay. To evaluate cell migration ability, a scratch wound healing method was used, and images of the scratch area were taken using a phase-contrast microscope. Cell morphology was evaluated by a scanning electron microscope after direct exposure for 72 h to each sealer disk. In the cell viability assay, there were no significant differences between the EndoSequence BC, BioRoot RCS, Endoseal MTA, and control groups in any experimental period (p > 0.05). In the cell migration assay, there were no significant differences between the EndoSequence BC, Endoseal MTA, and control groups in any experimental period (p > 0.05). BioRoot RCS exhibited slower cell migration relative to EndoSequence BC and Endoseal MTA for up to 72 h (p < 0.05). Conversely, it showed a similar wound healing percentage at 96 h (p > 0.05). In an evaluation of cell morphology, cells in direct contact with EndoSequence BC, BioRoot RCS, and Endoseal MTA disks showed superior spreading compared to those in contact with the AH Plus disk. In an Alizarin red staining assay, EndoSequence BC, BioRoot RCS, and Endoseal MTA showed a significant increase in mineralized nodule formation compared to the AH Plus group (p < 0.05). In conclusion, all calcium silicate-based root canal sealers tested in this study showed good biological properties and mineralization activity compared to conventional resin-based sealer.