Effects of vehicles on the physical properties and biocompatibility of premixed calcium silicate cements.

Premixed calcium silicate cements (pCSCs) contain vehicles which endow fluidity and viscosity to CSCs. This study aimed to investigate the effects of three vehicles, namely, polyethylene glycol (PEG), propylene glycol (PG), and dimethyl sulfoxide (DMSO), on the physicochemical properties and biocompatibility of pCSCs. The setting time, solubility, expansion rate, and mechanical strength of the pCSCs were evaluated, and the formation of calcium phosphate precipitates was assessed in phosphate-buffered saline (PBS). The effects of pCSC extracts on the osteogenic differentiation of mesenchymal stem cells (MSCs) were investigated. Finally, the tissue compatibility of pCSCs in rat femurs was observed. CSC containing PEG (CSC-PEG) exhibited higher solubility and setting time, and CSC-DMSO showed the highest expansion rate and mechanical strength. All pCSCs generated calcium phosphate precipitates. The extract of CSC-PG induced the highest expressions of osteogenic markers along with the greatest calcium deposites. When implanted in rat femurs, CSC-PEG was absorbed considerably, whereas CSC-PG remained relatively unaltered inside the femur.

Development of a tannic acid- and silicate ion-functionalized PVA-starch composite hydrogel for in situ skeletal muscle repairing.

The repair capacity of skeletal muscle is severely diminished in massive skeletal muscle injuries accompanied by inflammation, resulting in muscle function loss and scar tissue formation. In the current work, we developed a tannic acid (TA)- and silicate ion-functionalized tissue adhesive poly(vinyl alcohol) (PVA)-starch composite hydrogel, referred to as PSTS (PVA-starch-TA-SiO32-). It was formed based on the hydrogen bonding of TA to organic polymers, as well as silicate-TA ligand interaction. PSTS could be gelatinized in minutes at room temperature with crosslinked network formation, making it applicable for injection. Further investigations revealed that PSTS had skeletal muscle-comparable conductivity and modulus to act as a temporary platform for muscle repairing. Moreover, PSTS could release TA and silicate ions in situ to inhibit bacterial growth, induce vascularization, and reduce oxidation, paving the way to the possibility of creating a favorable microenvironment for skeletal muscle regeneration and tissue fibrosis control. The in vivo model confirmed that PSTS could enhance muscle fiber regeneration and myotube formation, as well as reduce infection and inflammation risk. These findings thereby implied the great potential of PSTS in the treatment of formidable skeletal muscle injuries.

Biocompatibility of mineral trioxide aggregate and biodentine as root-end filling materials: an in vivo study.

This study evaluated the biocompatibility of mineral trioxide aggregate (MTA) and Biodentine (BD) as root-end filling materials. Six mongrel dogs were divided into two equal groups according to the evaluation period; group A: one month and group B: three months. Three premolars of the same quadrant in each arch were used, summing up 36 teeth (6 teeth/dog). These teeth were randomly subdivided into three subgroups according to the root-end filling material used: MTA, BD and no root-end filling material (control). Endodontic access cavities were performed for induction of periapical pathosis. After the infection period, root canal instrumentation and obturation were accomplished. One day after root canal procedures, root-end surgery was performed. Surgical access was achieved and the root-end was resected approximately 3 mm above the apex. Root-end cavity was prepared ultrasonically and filled with the tested materials. All samples were evaluated by radiography and histopathology (Inflammation and new hard tissue formation). Data were collected and subjected to statistical analysis. In group A, MTA subgroup exhibited significant higher mean inflammatory score than BD subgroup (P < 0.05) while no significant difference was recorded between MTA and BD subgroups in group B (P > 0.05). Regarding mean mineralization score, there was no significant difference between all subgroups in both groups A and B (P > 0.05). Biodentine exhibited favorable biocompatibility in the initial stage of healing than MTA and comparable biomineralization. Clinical relevance: Biodentine could be considered as an acceptable alternative to MTA in peri-radicular surgeries.

An animal study on the effectiveness of platelet-rich plasma as a direct pulp capping agent.

Direct pulp capping (DPC) is a conservative approach for preserving tooth vitality without requiring more invasive procedures by enhancing pulp healing and mineralized tissue barrier formation. We investigated the effectiveness of Platelet Rich Plasma (PRP) vs. Mineral Trioxide Aggregate (MTA) as a DPC agent. Forty-two teeth from three mongrel dogs were divided into two equal groups. After three months, the animals were sacrificed to evaluate teeth radiographically using cone-beam computerized tomography, histopathologically, and real-time PCR for dentin sialophosphoprotein (DSPP), matrix extracellular phosphoglycoprotein (MEPE), and nestin (NES) mRNA expression. Radiographically, hard tissue formation was evident in both groups without significant differences (p = 0.440). Histopathologic findings confirmed the dentin bridge formation in both groups; however, such mineralized tissues were homogenous without cellular inclusions in the PRP group, while was osteodentin type in the MTA group. There was no significant difference in dentin bridge thickness between the PRP-capped and MTA-capped teeth (p = 0.732). The PRP group had significantly higher DSPP, MEPE, and NES mRNA gene expression than the MTA group (p < 0.05). In conclusion, PRP enables mineralized tissue formation following DPC similar to MTA, and could generate better cellular dentinogenic responses and restore dentin with homogenous architecture than MTA, making PRP a promising alternative DPC agent.

MicroRNA-146a-loaded magnesium silicate nanospheres promote bone regeneration in an inflammatory microenvironment.

Reconstruction of irregular oral-maxillofacial bone defects with an inflammatory microenvironment remains a challenge, as chronic local inflammation can largely impair bone healing. Here, we used magnesium silicate nanospheres (MSNs) to load microRNA-146a-5p (miR-146a) to fabricate a nanobiomaterial, MSN+miR-146a, which showed synergistic promoting effects on the osteogenic differentiation of human dental pulp stem cells (hDPSCs). In addition, miR-146a exhibited an anti-inflammatory effect on mouse bone marrow-derived macrophages (BMMs) under lipopolysaccharide (LPS) stimulation by inhibiting the NF-κB pathway via targeting tumor necrosis factor receptor-associated factor 6 (TRAF6), and MSNs could simultaneously promote M2 polarization of BMMs. MiR-146a was also found to inhibit osteoclast formation. Finally, the dual osteogenic-promoting and immunoregulatory effects of MSN+miR-146a were further validated in a stimulated infected mouse mandibular bone defect model via delivery by a photocuring hydrogel. Collectively, the MSN+miR-146a complex revealed good potential in treating inflammatory irregular oral-maxillofacial bone defects.

Dislodgement resistance and structural changes of tricalcium silicate-based cements after exposure to different chelating agents.

This study aimed to evaluate the dislodgement resistance and structural changes of different mineral trioxide aggregate cements (MTA) like Pro-Root MTA, Ortho MTA, and Retro MTA after exposure to sodium hypochlorite (NaOCl), NaOCl-Ethylenediaminetetraacetic acid (EDTA), 1-hydroxyethylidene-1, 1-bisphosphonate (Dual Rinse HEDP), and NaOCl-Maleic acid (MA). The root canal spaces of 150 dentine slices were obturated using tricalcium silicate cements and divided into 3 groups (n = 50): Group1: ProRoot MTA, Group2: Retro MTA, and Group3: Ortho MTA. The samples in each group were further subdivided into four experimental (n = 10) and one control groups (n = 10): 2.5% NaOCl-17% EDTA, Dual Rinse HEDP, 2.5% NaOCl-7% Maleic acid, 2.5% NaOCl, distilled water (control). The dislodgement resistance and structural changes of cements were measured. Use of DR HEDP resulted in higher dislodgement resistance compared to17% EDTA and 7% MA in the samples obturated with Ortho MTA and Pro-Root MTA (p<0.001). In Retro MTA group, samples treated with DR HEDP and 17% EDTA had higher dislodgment resistance compared to 7% MA (p<0.001). On microstructural and elemental analysis of all the three MTA cements, samples treated with 17% EDTA and 7% MA were more amorphous and granular when compared to DR HEDP, which was pettle shaped. Calcium level was decreased more in samples treated with 17% EDTA and 7% MA when compared to DR HEDP.

In vitro and in vivo evaluation of iRoot BP Plus as a coronal sealing material for regenerative endodontic procedures.

OBJECTIVES: To investigate in vitro effects of a nanoparticle bioceramic material, iRoot BP Plus, on stem cells from apical papilla (SCAP) and in vivo capacity to induce pulp-dentin complex formation. MATERIALS AND METHODS: The sealing ability of iRoot BP Plus was measured via scanning electron microscopy (SEM). SCAP were isolated and treated in vitro by iRoot BP Plus conditioned medium, with mineral trioxide aggregate (MTA) conditioned medium and regular medium used as controls, respectively. Cell proliferation was assessed by BrdU labeling and MTT assay and cell migration was evaluated with wound healing and transwell assays. Osteo/odontogenic potential was evaluated by Alizarin red S staining and qPCR. Pulp-dentin complex formation in vivo was assessed by a tooth slice subcutaneous implantation model. RESULTS: iRoot BP Plus was more tightly bonded with the dentin. There was no difference in SCAP proliferation between iRoot BP Plus and control groups (P > 0.05). iRoot BP Plus had a greater capacity to elevated cell migration (P < 0.05) and osteo/odontogenic marker expression and mineralization nodule formation of SCAP compared with MTA groups (P < 0.05). Furthermore, the new continuous dentine layer and pulp-like tissue was observed in the iRoot BP Plus group in vivo. CONCLUSIONS: iRoot BP Plus showed excellent sealing ability, promoted the migration and osteo/odontogenesis of SCAP and induced pulp-dentin complex formation without affecting the cell proliferation, which indicated iRoot BP Plus was a promising coronal sealing material in REPs. CLINICAL RELEVANCE: The coronal sealing materials play crucial roles for the outcomes of REPs. This study showed that iRoot BP Plus has good coronal sealing and promote pulp-dentin complex formation compared with MTA, providing experimental evidences for the clinical application of iRoot BP Plus as a promising coronal seal material in REPs.

Biocompatibility and Bioactivity of a Dual-Cured Resin-Based Calcium Silicate Cement: In Vitro and in vivo Evaluation.

INTRODUCTION: This study aimed to assess the biocompatibility and bioactivity of a dual-cured resin-based calcium silicate cement in vitro and in vivo. METHODS: For in vitro analyses, standardized samples were prepared using TheraCal LC, TheraCal PT, and ProRoot MTA. The amount of residual monomer released from TheraCal LC and TheraCal PT was assessed using liquid chromatography/mass spectrometry. Calcium ion release from the materials was evaluated using inductively coupled plasma-optical emission spectroscopy. Scanning electron microscopy and energy-dispersive X-ray spectroscopy were used to determine the calcium weight volume in the materials. For in vivo analysis, a rat direct pulp capping model with TheraCal LC, TheraCal PT, and ProRoot MTA groups (n = 16 per group) was used. The rats were euthanized after 7 or 28 days, and histological and immunohistochemical analyses (CD68 and DSPP) were performed. RESULTS: Bisphenol A-glycidyl methacrylate and polyethylene glycol dimethacrylate release from TheraCal PT was lower than that from TheraCal LC (P < .05). Similar results were obtained for calcium-ion release and calcium weight volume, with ProRoot MTA showing the highest values. In the in vivo evaluation, TheraCal PT showed significantly greater hard tissue formation than TheraCal LC (P < .017). TheraCal PT showed lower CD68 expression and greater DSPP expression than TheraCal LC (P < .017). There were no significant differences in the expression of CD68 or DSPP between the TheraCal PT and ProRoot MTA groups. CONCLUSIONS: Within the limitations of this study, the biocompatibility and bioactivity of TheraCal PT could be comparable to those of ProRoot MTA.

Histological evaluation of tissue reaction and new bone formation of different calcium silicate-based cements in rats.

BACKGROUND: The purpose of this study was to evaluate the local reactions and new bone formation of rat subcutaneous and bone tissue to different calcium silicate cements. METHODS: In this study, 80 rats were divided into five groups as control, BIOfactor MTA (BIO), NeoMTA Plus (NEO), MTA Repair Hp (REP), Biodentine (DENT) and then into two subgroups according to sacrification times (7, 30 days; n = 8). Polyethylene tubes filled with appropriate materials (test groups); empty tubes (control group) were implanted into the dorsum of each rat subcutaneously. For intraosseous implantation, materials were placed in the cavities created in tibia of rats. Subcutaneous tissue and tibia samples were stained with haematoxylin-eosin and subjected to histopathological analysis. A score (0-3) was used to grade inflammatory reaction and new bone formation. Data were analysed by Kruskal-Wallis and Mann-Whitney U tests (P < 0.05). RESULTS: Inflammatory reaction observed in subcutaneous and intraosseous tissues for 7 days decreased significantly in all groups over time (P < 0.05). It was determined that there was significant increase in new bone formation in REP, BIO, DENT groups over time (P < 0.05). CONCLUSION: Four contemporary bioceramic materials induced local inflammation and tissues changes shortly after subcutaneous implantation, which were reduced over time. In intraosseous implantation, all materials induced new bone formation over time. REGISTRATION NUMBER: ADJ-03-23-0134. © 2023 Australian Dental Association.

A comparative study of biological properties of three root canal sealers.

OBJECTIVES: The aim of this study was to evaluate the effects of Hiflow with other two kinds of root canal sealers on the biological behavior of stem cells from the apical papilla (SCAP), the influence on inflammatory cytokines release and its antibacterial effects. MATERIALS AND METHODS: Material extracts of Hiflow, iRoot SP, and AH Plus were prepared. Then, SCAP was incubated with extracts. The effects were evaluated by CCK-8, wound healing assay, ALP staining, alizarin red staining, and qRT-PCR. Meanwhile, polymorphonuclears (PMNs) and monocytes were isolated and treated with extracts for 4 h and 24 h respectively. Cell viability was analyzed by Annexin-V/PI double staining flow cytometry. The effects on the release of cytokines were observed by ELISA. The antibacterial effects of different sealers were tested against three kinds of bacteria found in chronic apical periodontitis. RESULTS: A series of results of SCAP showed that Hiflow and iRoot SP could promote cell proliferation, migration, and osteogenesis (p < 0.05). Although Hiflow was associated with greater cell apoptosis and necrosis when incubated with PMNs and monocytes (p < 0.05), it had an approximate release of anti-inflammatory cytokines with iRoot SP, which was higher than AH plus (p < 0.05). The co-culture showed that Hiflow and iRoot SP inhibited the colony formation of F. nucleatum (p < 0.05). However, both sealers had no obvious antibacterial effect on E. faecalis and P. gingivalis (p > 0.05). CONCLUSIONS: In summary, Hiflow and iRoot SP both had positive biological stimulus on SCAP. Meanwhile, Hiflow showed a better induction on anti-inflammatory cytokines over the others. All the properties mentioned above and its antibacterial effect of F. nucleatum promise Hiflow a bright application prospect in endodontic uses. CLINICAL RELEVANCE: References for clinical work to use BC Sealer Hiflow as a good biological root canal sealer.

Comparison of cytotoxic and apoptosis-inducing effects of MTA, propolis, and propolis-MTA on immature dental pulp stem cells.

BACKGROUND: Pulpotomy is a treatment option for the preservation of pulp vitality in primary teeth with extensive caries. Propolis is a natural resinous substance with optimal antimicrobial, anti-inflammatory, and immune-regulatory properties. Thus, this study aimed to compare the cytotoxic and apoptosis-inducing effects of mineral trioxide aggregate (MTA), propolis, and MTA-propolis on immature dental pulp stem cells (IDPSCs). METHODS: In this in vitro, experimental study, primary IDPSCs were exposed to propolis, MTA, and MTA-propolis for 24 and 72-h. The cytotoxicity and apoptosis-inducing effects were evaluated using the methyl thiazolyl tetrazolium (MTT) assay and flow cytometry, respectively. Data were analyzed using ANOVA and Tukey's test at 0.05 level of significance. RESULTS: The cytotoxicity of MTA and MTA-propolis was higher than that of propolis alone at both 24/48 h. In addition, all tested concentrations showed higher biocompatibility at 72-h compared with 24-h (P < 0.0001). In the assessment of apoptosis, propolis-MTA showed higher cell viability compared with other materials (P < 0.0001). CONCLUSION: Propolis-MTA showed higher biocompatibility than MTA. Addition of propolis to MTA improved cell proliferation in the first 24-h. Also, the cytotoxicity of propolis was lower than other materials in the first 24-h. Thus, propolis may serve as a promising pulp capping agent given that its other properties are approved.

Regenerative potential of a novel aloe vera modified tricalcium silicate cement as a pulp capping material: An animal study.

This study compared the histologic response of a pulp capping material Matreva MTA modified with different concentrations of aloe vera (AV) solutions to Biodentine cement. Ninety dogs' teeth were included and categorized according to the capping material into five groups (18 teeth each); Group I (Biodentine), group II (Matreva MTA), group III (Matreva MTA 10% AV), group IV (Matreva MTA 20% AV) and group V (Matreva MTA 30% AV). The histopathological findings were recorded at 2, 4, and 8 weeks. Matreva MTA and Biodentine groups showed the highest inflammatory cell count compared to the AV-modified Matreva MTA groups at 2- and 4-week intervals (p>0.05). Moreover, the AV-modified Matreva MTA and Biodentine groups showed higher dentin bridge thickness compared to unmodified Matreva MTA at different follow-up periods (p<0.05). AV can significantly enhance the in vivo bioactivity of Matreva MTA, inducing mild inflammation and good dentine bridge formation comparable to Biodentine.

Effect of Fluorohydroxyapatite on Biological and Physical Properties of MTA Angelus.

Objectives: This study aimed to assess the effect of addition of fluorohydroxyapatite (FHI) on biological and physical properties of mineral trioxide aggregate (MTA) Angelus. Materials and Methods: In this in vitro, experimental study, nano-FHI powder was first synthesized, and the morphology and chemical structure of particles were evaluated by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Three groups were evaluated in this study: MTA Angelus, MTA modified with 10% FHA, and MTA modified with 15% FHA. After mixing, the materials were applied to ring molds (10 mm diameter, 1 mm height), and the setting time of the three groups was evaluated according to ISO6876 and ASTMC266-03 with a Gillmore needle. The pH was measured using a pH meter at 24 and 48 hours and 7 days after mixing. The cytotoxicity of the materials was assessed in freshly mixed form and after 1 and 7 days using the methyl thiazolyl tetrazolium (MTT) assay according to ISO10993-5. Data were analyzed by one-way and repeated measures ANOVA and Tukey's test (alpha = 0.05). Results: The addition of FHA to MTA significantly decreased the initial setting time (P < 0.05) and had no significant effect on cell viability (compared with pure MTA Angelus) at 1 and 7 days. However, modified MTA groups in freshly mixed form showed significantly lower cell viability (P < 0.05). The pH remained alkaline at all time points. Conclusion: Addition of 15% FHA to MTA Angelus decreased its setting time with no adverse effect on cell viability (except for fresh form) or pH.

Designing Calcium Silicate Cements with On-Demand Properties for Precision Endodontics.

Calcium silicate (C3S) cements are available in kits that do not account for patients' specific needs or clinicians' preferences regarding setting time, radiopacity, mechanical, and handling properties. Moreover, slight variations in powder components and liquid content affect cement's properties and bioactivity. Unfortunately, it is virtually impossible to optimize several cement properties simultaneously via the traditional "one variable at a time" strategy, as inputs often induce trade-offs in properties (e.g., a higher water-to-powder ratio [W/P] increases flowability but decreases mechanical properties). Herein, we used Taguchi's methods and genetic algorithms (GAs) to simultaneously analyze the effect of multiple inputs (e.g., powder composition, radiopacifier concentration, and W/P) on setting time, pH, flowability, diametral tensile strength, and radiopacity, as well as prescribe recipes to produce cements with predicted properties. The properties of cements designed with GAs were experimentally tested, and the results matched the predictions. Finally, we show that the cements increased the genetic expression of odonto/osteogenic genes, alkaline phosphatase activity, and mineralization potential of dental pulp stem cells. Hence, GAs can produce cements with tailor-made properties and differentiation potential for personalized endodontic treatment.

Comparative biological properties of resin-free and resin-based calcium silicate-based endodontic repair materials on human periodontal ligament stem cells.

OBJECTIVES: To investigate the effect of three different calcium silicate-based materials (CSBM) on the biological behavior of human periodontal ligament stem cells (hPDLSCs). METHODS: Eluates of Biodentine, NeoPutty and TheraCal PT prepared at 1:1, 1:2, and 1:4 ratios were extracted under sterile conditions. The cytotoxicity of the extracts to the hPDLSCs was assessed using the MTT assay. Scratch wound healing assay was utilized for assessing cell migration. Scanning electron microscopy was used to detect cell attachment and morphology. Calcium ion release was measured using inductively coupled plasma-optical emission spectrometry; the pH-value was evaluated with a pH-meter. ANOVA with post hoc Tukey test was used for statistical analysis. RESULTS: Cell viability was significantly higher for Biodentine and NeoPutty at day 1 with all dilutions (p < 0.05), while at day 3 and day 7 with dilutions 1:2 and 1:4; all materials showed similar behavior (p > 0.05). Biodentine had the highest percentage of cell migration into the scratched area at day 1 for all dilutions (p < 0.05). Stem cells were attached favorably on Biodentine and NeoPutty with evident spreading, and intercellular communications; however, this was not shown for TheraCal PT. Biodentine showed the highest pH values and calcium ion release (p < 0.05). CONCLUSIONS: The resin-free CSBM showed better performance and favorable biological effects on hPDLSCs and were therefore considered promising for usage as endodontic repair materials. CLINICAL SIGNIFICANCE: Proper selection of materials with favorable impact on the host stem cells is crucial to ensure outcome in different clinical scenarios.

The Effect of Calcium hydroxide, Glass Ionomer and light cured resin modified calcium silicate on viability, proliferation and differentiation of stem cells from human exfoliated deciduous teeth.

BACKGROUND: Vital pulp therapy, based on the use of stem cells, has promising research and therapeutic applications in dentistry. It is essential to understand the direct effect of capping materials on the dental pulp stem cells of primary teeth, which contribute to the healing powers of the tooth. The aim of this study is to evaluate the effect of different capping materials (Calcium Hydroxide (DyCal®) - Glass Ionomer (Fuji IX®) and light-cured resin modified calcium silicate (TheraCal LC®)) on the viability, proliferation, and differentiation of stem cells from human exfoliated deciduous teeth (SHEDs). METHODS: SHEDs were isolated from extracted primary teeth, then divided into four groups and each of the capping materials were applied to the stem cells as follows: group I the controls, group II with Ca(OH)2, group III with the GIC, and group IV with the Theracal LC. For all groups assessment of viability and proliferation rate was done using the MTT cell proliferation assay. Also, Differentiation was evaluated by measuring the gene expression of Alkaline phosphatase enzyme activity (ALP) and Dentin matrix protein-1 (DMP1) through quantitative real-time PCR. Morphological assessment was conducted using Alizarin Red S staining. All evaluations were performed after 7 and 14 days of culture. RESULTS: TheraCal LC showed the highest values of proliferation, which was significant only compared to the control group after 2 weeks (p = 0.012). After one week, TheraCal LC showed the highest significant values of ALP and DMP1 compared to all other groups (p < 0.001). CONCLUSION: The three materials under study are biocompatible, maintain viability, and stimulate the proliferation and differentiation of SHEDs. However, TheraCal LC allows better proliferation of SHEDs than Dycal Ca(OH)2 and Fuji IX GIC.

[In vitro study on cytotoxicity, osteogenic potential and antibacterial activity of silicate root canal sealers].

PURPOSE: To evaluate the in vitro biocompatibility and antibacterial activity of a new type of strontium silicate-based C-Root SP root canal sealer, and to provide a reference for clinical selection of sealers. METHODS: C-Root SP, iRoot SP and AH Plus extracts were prepared, L929 cells and MC3T3-E1 cells were cultured in vitro, and the cytotoxicity and osteogenic potential of the three sealers were compared. Fresh sealers were mixed with Enterococcus faecalis solution and the antibacterial activity of the sealer was determined by direct contact text (DCT). SPSS 25.0 software package was used for statistical analysis. RESULTS: At 24, 48, and 72 h, the cytotoxicity of the sealers in each group were significantly different (P＜0.01). Compared with AH Plus, the cytotoxicity of C-Root SP was lower (P＜0.01). C-Root SP was superior to AH Plus in promoting the activity of alkaline phosphatase(ALP) (P＜0.01). iRoot SP was the strongest in promoting the formation of mineralized nodules, followed by C-Root SP, and the weakest was AH Plus(P＜0.01). C-Root SP inhibited the growth of Enterococcus faecalis, and its antibacterial rate was significantly higher than AH Plus(P＜0.01). CONCLUSIONS: The strontium silicate root canal sealer C-Root SP has low cytotoxicity, certain osteogenic potential and antibacterial activity against Enterococcus faecalis, so it can be used for root canal filling.

Effect of blood contamination on marginal adaptation of cold ceramic and MTA angelus: a scanning electron microscopic study.

BACKGROUND: This study aimed to assess the effect of blood contamination on marginal adaptation of cold ceramic (CC) and mineral trioxide aggregate (MTA) Angelus using scanning electron microscopy (SEM). METHODS: This in vitro experimental study was conducted on 24 extracted single-rooted human teeth. After cleaning and shaping, the root canals were filled with lateral compaction technique. The apical 3 mm of the roots was cut, and cavities with 3 mm depth were created at the apex. The teeth were randomly assigned to two group (n = 12) for the application of CC and MTA Angelus as retrograde filling materials. CC and MTA Angelus were prepared by mixing the powder with blood, and applied in the cavities. After 24 h, their marginal adaptation to the canal walls was assessed by SEM. Data were statistically analyzed by t-test (alpha = 0.05). RESULTS: The mean marginal gap was 8.98 µm in the CC, and 16.26 µm in the MTA Angelus group; this difference was statistically significant (P < 0.001). CONCLUSIONS: The present in vitro study revealed that following complete blood contamination of powder, CC showed significantly superior marginal adaptation than MTA Angelus as shown by SEM assessment.

The Effects of Calcium Silicate- and Calcium Hydroxide-based Root Canal Sealers on Postoperative Pain: A Randomized Clinical Trial.

INTRODUCTION: This study aimed to compare the postoperative pain level changes resulting from using calcium silicate- (EndoSeal MTA) and calcium hydroxide-based (Sealapex) root canal sealers in mandibular first and second molar teeth with symptomatic apical periodontitis. METHODS: A total of 60 patients with symptomatic apical periodontitis in their lower molar teeth were randomly allocated into 2 groups according to sealer type (n = 30). Demographic data, including gender, age, and smoking habit, and preoperative pain measures were recorded. Root canal treatments were performed in a single visit. Postoperative pain measurements and analgesic intake were measured at 6, 12, 24, and 48 hours and after 3, 5, and 7 days using the visual analog scale. The data were statistically analyzed using a chi-squared test (to compare gender, age, smoking habit, analgesic intake, and sealer extrusion), the Mann-Whitney U test (to compare pain levels), Friedman tests (for the evaluations of the reduction in pain levels over time), and Spearman's correlation test (to analyze the relationships of age, gender, smoking habit factors with postoperative pain) (P = .05). RESULTS: The statistical analysis showed no significant differences between the groups in postoperative pain and analgesic intake at any of the time intervals evaluated (P > .05). CONCLUSIONS: Patients treated with calcium silicate- and calcium hydroxide-based root canal sealers experienced similar postoperative pain and no statistically significant differences were observed in analgesic intake.

Chemomechanical Properties and Biocompatibility of Various Premixed Putty-type Bioactive Ceramic Cements.

INTRODUCTION: This study aimed to evaluate the chemomechanical properties and biocompatibility of recently introduced premixed putty-type bioactive ceramic cements (PPBCs). METHODS: Including ProRoot MTA (PMTA) as a control, BC RRM fast-set putty (BCPT), Well-Root PT (WRPT), One-Fil PT (OFPT), and Endocem MTA premixed (ECPM) were compared to evaluate setting time, radiopacity, pH change, and microhardness. Biocompatibility on human dental pulp cells was compared using CCK-8 assay. Mineralization potential was evaluated using alkaline phosphatase activity, Alizarin Red S (ARS) staining, and quantitative real-time polymerase chain reaction with odontogenic gene marker. For data analysis, 1-way analysis of variance and Tukey's post hoc test were used at the significance level of 95%. RESULTS: Among the PPBCs, BCPT presented the longest (552 ± 27) setting time (minutes) and others showed significantly shorter time than PMTA (334 ± 22) (P < .05). WRPT (6.20 ± 0.54) and OFPT (5.82 ± 0.50) showed significantly higher radiopacity values (mmAl) and others showed similar value compared with PMTA (P > .05). All PPBCs showed high alkaline pH from fresh materials and tended to increase according to time periods from 30 minutes to 12 hours. ECPM showed the highest value of microhardness (81.62 ± 5.90), WRPT showed similar, and others showed lower than PMTA (P < .05). All PPBCs showed biocompatibility in CCK-8 assay. All PPBCs showed similar or better value compared with PMTA in ALP and ARS staining, and ALP and DSPP marker expression (P < .05). CONCLUSIONS: The PPBCs showed clinically acceptable chemomechanical properties and favorable mineralization potential.