Calcium Silicate-based Materials Research Articles

Clinical, radiographic, and histological evaluation of three different pulp-capping materials in indirect pulp treatment of primary teeth: a randomized clinical trial.

The aim of this randomized, controlled, three-arm parallel group, and double-blinded clinical trial was to evaluate the clinical, radiographic, and histopathological success of three different pulp-capping materials in one-stage indirect pulp treatment of primary teeth. The study included a total of 109 patients aged 5-9years who had primary teeth with deep carious lesions and symptoms of reversible pulpitis. The teeth were divided into three groups according to the pulp-capping agents: (I) hard-setting calcium hydroxide (Dycal) (control group) (n = 36), (II) bioactive tricalcium silicate (Biodentine) (n = 37), and (III) resin-based tricalcium silicate (TheraCal LC) (n = 36). All the teeth were evaluated clinically and radiographically at 6, 12, 18, and 24months postoperatively. A total of 23 primary mandibular second molars that were in their regular exfoliation period (24-40months) were extracted and fixed in 10% formaldehyde solution. The specimens were evaluated histologically to assess the integrity of the odontoblastic layer, tertiary dentin formation quality of the dentin formed, severity of pulpitis, and other pulpal changes. Data were analyzed using Fisher's exact test, Pearson's chi-square test, and McNemar's test (p = 0.05). At the end of the 24-month follow-up period, the clinical and radiographic success rates for Dycal, Biodentine, and TheraCal LC were 100%, 100%, and 93.3%, respectively, and there was no significant difference among the groups (p > 0.05). However, the TheraCal LC group was statistically unsuccessful when compared to the other groups with regard to the integrity of the odontoblastic layer, severity of pulpitis, and other pulpal changes in histological examination (p < 0.05). Indirect pulp capping exhibited high clinical and radiographic success rates in the treatment of primary teeth regardless of the chosen pulp-capping agent. However, histological examination indicated that the pulp status was affected by the chosen capping material especially when selecting a resin-containing material such as TheraCal LC. Resin-free calcium silicate-based materials appear to be more favorable in the indirect pulp treatment of primary teeth, particularly in young-age groups that require long-term success.

Microscopic and elemental characterization of hydrated dental pulp capping agents.

Context:Characteristics of dental pulp capping agents may influence its interaction with the pulpal cells and can impact the treatment outcome.Aims:This study aims to microscopically characterize various pulp capping agents following hydration.Settings and Design:Original research.Materials and Methods:Disk-shaped specimens of five calcium silicate-based materials, i.e., mineral trioxide aggregate (MTA) Angelus, Biodentine, TheraCal LC, ApaCal ART, and Endocem MTA were prepared. After final set, the materials were immersed in 10 mL of deionized water for 14 days at 37°C. The set materials were characterized by scanning electron microscopy (SEM), X-ray energy dispersive analysis (EDX), and X-ray diffraction (XRD) analysis along with pH analysis of the storage solution using pH meter.Results:On SEM analysis, all the materials showed crystalline deposition on the cement surface with Biodentine exhibiting the most dense and homogenous microstructure. Calcium-silicate-hydrate and calcium hydroxide (CH) were observed as dark-grey and light-grey matrix material, respectively. EDX analysis revealed a high concentration of calcium. The other major elements were oxygen and carbon. The surface calcium concentration in the tested specimens was as follows: Biodentine (42.59 wt.%) > MTA Angelus (38.51wt.%) > Endocem MTA (30.24wt.%) > TheraCal LC (27.51wt.%) > ApaCal ART (22.02wt.%). On XRD analysis, all the materials exhibited peaks for tricalcium silicate and CH, after 14 days of hydration.Conclusions:The higher surface calcium level in Biodentine and MTA Angelus may enhance reparative dentin formation. The surface calcium concentration of Endocem MTA and ApaCal ART was found to be lesser than that of MTA Angelus, but with the added advantage of fast-setting property. Hence, they are potential alternative materials for vital pulp therapy.

Do intracanal medications used in regenerative endodontics affect the bond strength of powder-to-liquid and ready-to-use cervical sealing materials?

Aim:This study evaluated the effect of four intracanal medications commonly used in regenerative endodontic procedures on the bond strength of four calcium silicate-based materials, in which two are powder-to-liquid products (MTA and MTA-HP) and the other are ready-to-use materials (EndoSequence Root Repair Material Fast Set Putty [ERRM] and Bioceramic Repair [BIO-C Repair]).Methods:Ten bovine central incisors were selected and 4 slices (1.0 ± 0.1 mm) were prepared from each root. Next, four 0.8-mm wide holes were drilled in each slice and specimens were filled with one of the following intracanal medications: triple antibiotic paste, double antibiotic paste, calcium hydroxide with distilled water, and calcium hydroxide with 2% chlorhexidine gel. After 21 days, holes were filled with one of the materials: MTA, MTA-HP, ERRM, or BIO-C Repair. After storage, push-out test and failure analysis were performed. Data were submitted to analysis of variance in a 4 × 4 factorial scheme. Tukey's test was used for multiple comparisons.Results:The use of different interappointment dressings did not influence the results (P > 0.05). ERRM and BIO-C Repair presented significantly higher values than MTA and MTA-HP (P < 0.0001). Specimens showed a 100% occurrence of adhesive failures.Conclusion:The use of different intracanal medications presented similar impact on bond strength of calcium silicate-based materials. Ready-to-use ERRM and BIO-C Repair materials presented the best push-out values to dentine, whereas powder-to-liquid MTA and MTA-HP cements showed the lowest results.

Cytotoxicity and Bioactivity of Calcium Silicate-based Cements in a Culture of Stem Cells from the Apical Papilla.

The present in vitro study evaluated the cytotoxicity and bioactivity of commonly-used calcium silicate-based cements in a culture of stem cells from the apical papilla (SCAPs). NeoMTA Plus (Avalon Biomed), BiodentineTM (Septodont) and MTA HP Repair (Angelus) cements were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and sulphorhodamine-B (SRB) viability assays. Cells were seeded (1*104 cells mL-1) in 96-well plates and exposed to 1:4 diluted extract in 24 h and 72 h. For the analysis of bioactivity, alkaline phosphatase (ALP) enzyme activity and Alizarin Red S (AZR) were assessed after 24 h of cell culture in 12-well plates (1*104 cells mL-1), where cells were exposed to 1:4 diluted extract on days 1 and 7. Minimum Essential Eagle's Medium alpha modification was used as control. ANOVA and Tukey's post hoc test were used to compare the different cements at each experimental time point. No significant differences were found between the cements and the control specimens on MTT at 24 h and 72 h (P>0.05); however, the calcium silicate-based cement materials showed higher cell viability compared to the control group (P<0.05). In the 24-h SRB, NeoMTA Plus showed lower cell viability than BiodentineTM and MTA HP Repair (P<0.05), with all groups similar to the control group (P>0.05). Compared to 24-h results, only NeoMTA Plus presented increased cell viability at 72 h (P<0.05). ALP activity was similar across the materials at 1 day (P>0.05). ALP activity was higher for BiodentineTM when compared to NeoMTA Plus (P<0.05), nevertheless, it was similar to MTA HP Repair and control groups (P>0.05) at 7 days. At 1- and 7-day periods of AZR assay, BiodentineTM presented higher levels of mineralized nodule formation (P<0.05). All evaluated calcium silicate-based cements demonstrated cell viability and bioactivity, suggesting that these (bio)materials may be indicated for use in regenerative dentine-pulp complex procedures.

A micro-computed tomographic study using a novel test model to assess the filling ability and volumetric changes of bioceramic root repair materials.

ObjectivesNew premixed bioceramic root repair materials require moisture for setting. Using micro-computed tomography (micro-CT), this study evaluated the filling ability and volumetric changes of calcium silicate-based repair materials (mineral trioxide aggregate repair high-plasticity [MTA HP] and Bio-C Repair, Angelus), in comparison with a zinc oxide and eugenol-based material (intermediate restorative material [IRM]; Dentsply DeTrey).Materials and MethodsGypsum models with cavities 3 mm deep and 1 mm in diameter were manufactured and scanned using micro-CT (SkyScan 1272. Bruker). The cavities were filled with the cements and scanned again to evaluate their filling capacity. Another scan was performed after immersing the samples in distilled water for 7 days to assess the volumetric changes of the cements. The statistical significance of differences in the data was evaluated using analysis of variance and the Tukey test with a 5% significance level.ResultsBio-C Repair had a greater filling ability than MTA HP (p < 0.05). IRM was similar to Bio-C and MTA HP (p > 0.05). MTA HP presented the largest volumetric change (p < 0.05), showing more volume loss than Bio-C and IRM, which were similar (p > 0.05).ConclusionsBio-C Repair is a new endodontic material with excellent filling capacity and low volumetric change. The gypsum model proposed for evaluating filling ability and volumetric changes by micro-CT had appropriate and reproducible results. This model may enhance the physicochemical evaluation of premixed bioceramic materials, which need moisture for setting.

Investigation of a modified hydraulic calcium silicate-based material - Bio-C Pulpo.

This study evaluated the physicochemical, biological, and antimicrobial properties of a new hydraulic calcium silicate-based modified material, and compared it with MTA Repair HP and MTA Angelus. The materials were assessed regarding color luminosity (L), color change, radiopacity, setting time, and ISO 6876:2012 linear flow. Volumetric filling and volume change were evaluated using microcomputed-tomography (µCT). Chemical characterization after 28 days in Hank's Balanced Salt Solution (HBSS) and pH analysis were also assessed. Biological characterization of cytotoxicity and microbiological assessment were also undertaken. Shapiro-Wilk, ANOVA, Levene and post hoc analyses with Bonferroni correction were performed, adopting a 5% significance level (p <0.05). Bio-C Pulpo exhibited the highest L values after 90 days. All tested materials demonstrated color change during the analyses, and had radiopacity above 5 mm Al. MTA Repair HP set faster than Bio-C Pulpo, whereas the latter had the highest linear flow. MTA Repair HP had the highest volumetric filling in µCT analysis. Bio-C Pulpo showed the highest alkalinity during all tested periods, and the highest volumetric loss (above 9%), in comparison with MTA Repair HP and MTA Angelus. Bio-C Pulpo did not form calcium hydroxide after hydration. MTA Repair HP demonstrated the highest cytocompatibility, and Bio-C Pulpo, the highest cytotoxicity. No inhibition halos were observed for any material, and similar higher turbidity values were seen after direct contact. Composition additives used in Bio-C Pulpo modified its properties, and both the absence of calcium hydroxide deposition after hydration, and the related cytotoxicity of this material are of particular concern.

Macrophage modulation of dental pulp stem cell activity during tertiary dentinogenesis

The interaction between immune cells and stem cells is important during tissue repair. Macrophages have been described as being crucial for limb regeneration and in certain circumstances have been shown to affect stem cell differentiation in vivo. Dentine is susceptible to damage as a result of caries, pulp infection and inflammation all of which are major problems in tooth restoration. Characterising the interplay between immune cells and stem cells is crucial to understand how to improve natural repair mechanisms. In this study, we used an in vivo damage model, associated with a macrophage and neutrophil depletion model to investigate the role of immune cells in reparative dentine formation. In addition, we investigated the effect of elevating the Wnt/β-catenin pathway to understand how this might regulate macrophages and impact upon Wnt receiving pulp stem cells during repair. Our results show that macrophages are required for dental pulp stem cell activation and appropriate reparative dentine formation. In addition, pharmacological stimulation of the Wnt/β-catenin pathway via GSK-3β inhibitor small molecules polarises macrophages to an anti-inflammatory state faster than inert calcium silicate-based materials thereby accelerating stem cell activation and repair. Wnt/β-catenin signalling thus has a dual role in promoting reparative dentine formation by activating pulp stem cells and promoting an anti-inflammatory macrophage response.

Evaluation of antimicrobial efficacy of three calcium silicate-based materials using tube dilution: An in vitro study

Periapical pathosis is considered as a persistent microbial infection throughout the treatment period of root canal procedures. Recently the prevalence of endodontic failures is huge and this primarily accounts for the periapical pathogens; mainly Enterococcus faecalis and Candida albicans. Thus, with the advent of newer materials; identification of the most appropriate sealing material with highest antimicrobial efficacy is essential for endodontic success. To evaluate and compare the antimicrobial efficacy of MTA Angelus, Biodentine and Theracal LC against Enterococcus faecalis and Candida albicans. An in-vitro study was conducted using three silicate-based cements; MTA Angelus, Biodentine and Theracal LC. Their antimicrobial efficacy was evaluated using Tube dilution method and their Minimum inhibitory concentration (MIC) and Bacterial counts (CFU’s) were assessed and compared. Statistical analysis was done using Paired t-test and ANOVA at 95% confidence interval (p value &amp;#60;0.05).The MIC was highest and CFU’s were lowest with Biodentine in comparison with other two materials.There were statistically significant differences noted between Biodentine and MTA angelus: Our study results conclude that Biodentine was found to be more anti-bacterial as compared to MTA angelus and theracal LC.

Conservative Management of Mature Permanent Teeth with Carious Pulp Exposure

Vital pulp therapy (VPT) in mature permanent teeth with carious pulp exposure has been a matter of debate, with root canal therapy being the conventional standard of care. Previously reported negative outcomes for VPT in these teeth were based on data from studies that have used calcium hydroxide in direct pulp capping and partial and full pulpotomy. The introduction of hydraulic calcium silicate-based materials with sealing and bioactive potentials have opened a new era in VPT with more favorable results. Understanding the histopathology and histobacteriology of the cariously exposed pulp and the healing potential of the inflamed pulp could guide the decision-making process toward an ultraconservative management of these teeth. However, proper case selection, strict aseptic condition, capping material, and good coronal seal are crucial for long-term success.

Influence of Powder-to-Gel Ratio on Physicochemical Properties of a Calcium Silicate Sealer

Differences in liquid-to-powder ratio can affect the properties of calcium silicate-based materials. This study assessed the influence of powder-to-gel ratio on physicochemical properties of NeoMTA Plus. Setting time (minutes), flow (mm and mm²), pH (at different periods), radiopacity (mm Al) and solubility (% mass loss) were evaluated using the consistencies for root repair material (NMTAP-RP; 3 scoops of powder to 2 drops of gel) and root canal sealer (NMTAP-SE; 3 scoops of powder to 3 drops of gel), in comparison to Biodentine cement (BIO) and TotalFill BC sealer (TFBC). Statistical analysis was performed using one-way ANOVA and Tukey tests (α=0.05). BIO had the shortest setting time, followed by NMTAP-RP and NMTAP-SE. TFBC showed the highest setting time and radiopacity. BIO, NMTAP-RP, and NMTAP-SE had similar radiopacity. All materials promoted an alkaline pH. NMTAP-RP/SE presented lower solubility than BIO and TFBC. Regarding the flow, TFBC had the highest values, followed by NMTAP-SE, and NMTAP-RP. BIO had the lowest flow. In conclusion, NMTAP in both powder-to-gel ratios showed high pH and low solubility. The increase in the powder ratio decreased the setting time and flow. These findings are important regarding the proper consistency and work time to clinical application.

The Disease Process, Diagnosis and Treatment of Invasive Cervical Resorption: A Review.

Invasive cervical resorption (ICR) is a localized, subepithelial, supra-osseous resorptive process of the tooth. Although there are several predisposing factors associated with ICR, its etiology and pathogenesis are poorly understood. The damage to the protective layer on the external root surface appears to allow for the attachment of clastic cells and initiate the resorptive process, which is confined by the inner protective pericanalar resorption-resistant sheet surrounding the root canal space. The use of cone-beam computed tomography (CBCT) is recommended for the diagnosis and assessment of a resorptive lesion. Based on the thorough evaluation of the size and location of the ICR lesion using CBCT, surgical or nonsurgical treatment can be chosen to address the source of the resorption. This review discusses the current status of knowledge regarding the biology of ICR lesions as well as their external or internal treatment using hydraulic calcium silicate-based materials. Future clinical outcome studies are necessary to evaluate the impact of hydraulic calcium silicate-based materials on the healing of ICR lesions.

Effect of Antiseptic Agents on the Surface Microhardness of Calcium Silicate-Based Materials

Mineral trioxide aggregate (MTA), which was originally derived from Portland cement, has been developed as a material for perforation repair and root-end filling...

Pre-application of dentin bonding agent prevents discoloration caused by mineral trioxide aggregate

BackgroundTo evaluate tooth discoloration by newly developed calcium silicate-based materials, and to examine the pre-application of dentin bonding agent (DBA) for preventing discoloration caused by mineral trioxide aggregate (MTA).MethodsThe roots of 50 premolars were randomly divided into five groups (n = 10) and cavities were prepared from resected root surfaces. MTA was placed in the cavities of teeth belonging to the ProRoot MTA (MTA) and RetroMTA (RMTA) groups. For teeth belonging to the ProRoot + DBA (MTA-B) and RetroMTA + DBA (RMTA-B) groups, DBA was first applied to the cavities prior to the addition of MTA. Teeth in the control group were restored with composite resin only (i.e., without MTA). After 12 weeks, MTA was removed from the MTA and RMTA groups and bleaching agents were applied for 3 additional weeks. Color assessments were recorded at baseline, and 1, 4, and 12 weeks, as well as after bleaching. A one-way ANOVA was performed to assess the differences between the two types of MTAs and color changes following DBA pre-application in each MTA group. A p-value of < 0.05 was considered indicative of statistical significance.ResultsFollowing 12 weeks of MTA treatment, there was a significant difference between the discoloration in the MTA and RMTA groups (p < 0.05). However, no significant difference was observed between the RMTA and RMTA-B groups (p > 0.05). Following bleaching, the color changes (ΔE values) of the MTA group were not significantly different from those of the MTA-B group (p > 0.05). The difference of ΔE between the RMTA group after internal bleaching and the RMTA-B group was also not significant (p > 0.05).ConclusionsRetroMTA caused significantly less discoloration than ProRoot MTA. Pre-application of DBA reduced discoloration caused by ProRoot MTA. MTA discoloration was improved equally well between DBA pre-application and post-bleaching.

Investigating the effect of bicarbonate ion on the structure and strength of calcium silicate-based dental restorative material—Biodentine

Investigating the effect of carbonation on the strength and structure of calcium silicate-based cement (Biodentine™) in the presence of bicarbonate ion. Cylindrical samples of Biodentine (N = 120) were prepared and cured in deionised water (DW) or bicarbonate solution (BC) for 1 and 2days and 1, 2 and 4weeks. After storage, the compressive strength of cured samples was tested using a universal testing machine, and carbonate was quantified on the surface or within the structure of samples using Raman and Fourier transform infrared spectroscopy, respectively. Levels of calcium and silicon ions and pH were measured after each storage duration, and 4-week-old samples were imaged using scanning electron microscopy. Cement's compressive strength was significantly higher after curing in BC for 2days. This was associated with significantly higher levels of carbonate on the surface of the cement but not within its structure. Levels of calcium and silicon ions and pH in BC dropped significantly after 1day and remained at a steady lower level. The pH and calcium ion levels dropped gradually over 4weeks in DW, unlike the silicon ion level that maintained a steady higher level than in BC. Our results indicate that Biodentine exhibited higher strength in the presence of bicarbonate, which can be explained by the carbonation process that encouraged the formation of calcium carbonate on the cement's surface. Carbonation should be of more consideration when studying calcium silicate-based cements, with curing and testing conditions closer to the intraoral conditions.

Mineralization-inducing potentials of calcium silicate-based pulp capping materials in human dental pulp cells.

BackgroundThis study was performed to provide a long-term bacterial seal through the formation of reparative dentin bridge, calcium silicate-based pulp capping materials have been used at sites of pulpal exposure. The aim of this study was to evaluate the mineralization-inducing potentials of calcium silicate-based pulp capping materials (ProRoot MTA [PR], Biodentine [BD], and TheraCal LC [TC]) in human dental pulp cells (HDPCs).MethodsSpecimens of test materials were placed in deionized water for various incubation times to measure the pH variation and the concentration of calcium released. The morphology of HDPCs cultured on the specimens was examined using a confocal laser scanning microscope (CLSM). Alizarin red S staining and alkaline phosphatase assays were used to evaluate mineralization-inducing potentials of the capping materials.ResultsBD showed the highest calcium release in all test periods, followed by PR and TC. (p<0.05). All experimental groups showed high alkalinity after 1 day, except at 14 days. BD showed the highest cell viability compared with PR and TC after 1 and 3 days, while TC showed the lowest value (p<0.05). The CLSM analysis showed that cells were well adhered and expressed actin filaments for all pulp capping materials. Mineralization by PR and BD groups was higher than that by TC group based on alizarin red S staining. BD showed significantly higher alkaline phosphatase activity than PR and TC, while TC showed the lowest value (p<0.05).ConclusionWithin the limitations of the in vitro study, BD had higher mineralization-inducing potential than PR and TC.

Bioactivity and Physicochemical Properties of Three Calcium Silicate-Based Cements: An In Vitro Study.

Objective This study evaluated the bioactivity and physicochemical properties of three commercial calcium silicate-based endodontic materials (MTA, EndoSequence Root Repair Material putty, and Biodentine™). Material and Methods. Horizontal sections of 3 mm thickness from 18 root canals of human teeth were subjected to biomechanical preparation with WaveOne Gold large rotary instruments. The twelve specimens were filled with three tested materials (MM-MTA, EndoSequence Root Repair Material putty, and Biodentine™) and immersed in phosphate-buffered saline for 7 and 30 days. After this period of time, each specimen of each material was processed for morphological observation, surface precipitates, and interfacial dentin using SEM. In addition, the surface morphology of the set materials, without soaking in phosphate-buffered solution after one day and after 28 days stored in phosphate-buffered saline, was evaluated using SEM; also, the pH of the soaking water and the amount of calcium ions released from the test materials were measured by using an inductively coupled plasma-optical emission spectroscopy test. Data obtained were analyzed using one-way analysis of variance and Tukey's honest significant difference test with a significance level of 5%. Result The formation of precipitates was observed on the surfaces of all materials at 1 week and increased substantially over time. Interfacial layers in some areas of the dentin-cement interface were found from one week of immersion. All the analyzed materials showed alkaline pH and capacity to release calcium ions; however, the concentrations of released calcium ions were significantly more in Biodentine and ESRRM putty than MM-MTA (P < 0.05). ESRRM putty maintained a pH of around 11 after 28 days. Conclusion Compared with MM-MTA, Biodentine and ESRRM putty showed significantly more calcium ion release. However, exposure of three tested cements to phosphate-buffered solution resulted in precipitation of apatite crystalline structures over both cement and dentin that increased over time. This suggests that the tested materials are bioactive.

Farklı İrrigasyın Solüsyonlarının Çeşitli Kalsiyum Silikat Bazlı Materyaller Üzerindeli Renk Değişimine Etkisinin İncelenmesi

Background:To compare the color stabilities of wMTA Angelus, Biodentine, EndoSequence Root Repair Material, and BIO MTA+. Calcium silicate-based materials in response to the exposure to different irrigation solutions. Methods:Four groups of materials (4 samples in each) were involved in the present study. Each of materials was homogenously mixed and placed in each container.After the setting time, all of the samples colors before the contact with solutions were determined by using a spectrophotometer. Then one sample from each material was kept in each of 4 irrigation solutions for 24 hours: distilled water, 5.25% NaOCl, 2% chlorhexidine gluconate (CHX] and 17% ethylenediaminetetraacetic acid (EDTA]. At the end of this period, the samples were taken out of the solutions and the color measurements were repeated. Results:Among all the materials, the discoloration of distilled water group was found to be the lowest at statistically significant level. The discoloration when exposed to Biodentine and wMTA Angelus irrigation solutions was at clinically acceptable level when compared to ES and BIO MTA+. Conclusions:Biodentine and wMTA Angelus may be used by clinicians as an alternative when the esthetic concerns play dominant role.Keywords:BIO MTA+; Biodentine; wMTA Angelus; EndoSequence Root Repair Material; Color Stability;

Bio-Inductive Materials in Direct and Indirect Pulp Capping-A Review Article.

The article is aimed at analyzing the available research and comparing the properties of bio-inductive materials in direct and indirect pulp capping procedures. The properties and clinical performances of four calcium-silicate cements (ProRoot MTA, MTA Angelus, RetroMTA, Biodentine), a light-cured calcium silicate-based material (TheraCal LC) and an enhanced resin-modified glass-ionomer (ACTIVA BioACTIVE) are widely discussed. A correlation of in vitro and in vivo data revealed that, currently, the most validated material for pulp capping procedures is still MTA. Despite Biodentine’s superiority in relatively easier manipulation, competitive pricing and predictable clinical outcome, more long-term clinical studies on Biodentine as a pulp capping agent are needed. According to available research, there is also insufficient evidence to support the use of TheraCal LC or ACTIVA BioACTIVE BASE/LINER in vital pulp therapy.

Chemico-physical and mechanical evaluation of three calcium silicate-based pulp capping materials

AimThis study compared biointeractivity (pH of soaking water and calcium ions), porosity, water sorption, solubility, compressive strength, lap shear strength, as well as the apatite forming ability of three calcium silicate-based capping materials: Mineral trioxide aggregate (MTA), Biodentine (BD) and Tech Biosealer capping (BS). MethodsOne hundred and five discs of the tested materials were prepared in compliance with the manufacturer’s instructions. The materials' pastes were placed in Teflon molds and allowed to set before testing. The pH and Ca+2 ions were measured by a potentiometric method. Porosity, water sorption, and solubility were calculated through the measurement of initial mass, mass, saturated mass and dry mass. Apatite forming ability was measured by an Environmental Scanning Electron Microscope that was connected to a secondary electron detector for energy dispersive X-ray analysis. Meanwhile compressive strength was measured by a computer controlled universal testing machine. Lap shear strength was measured by computer software on the testing machine. All data were statistically analyzed. ResultsThe tested materials showed Ca ions release and alkalization, which decreased with soaking time. The BD exhibited a very high Ca release at both short (3 h) and long times (28 days). Significant high values of open and apparent porosities, water sorption, and solubility were measured for BS, which was followed by the MTA then BD (P < .05). The BD had significant higher compressive and lap shear bond strength than the MTA and BS (P < .05). ConclusionMTA, BD and BS are biointeractive bioactive materials that possess the ability to release ions and form calcium phosphate deposits. Unlike BD, BS is incapable of alternating MTA in pulp capping due to its high porosities, water sorption and solubility, as well as poor compressive and lap shear bond strength.

Effect of irrigation solutions on the coronal discoloration induced by mineral trioxide aggregate cements containing different radiopacifiers

The aim of this study was to assess the discoloration of coronal tooth structure irrigated with different irrigation solutions and filled with calcium silicate-based materials containing bismuth oxide or calciumzirconia complex as radiopacifier. In this ex vivo study, 72 bovine enamel-dentin blocks were prepared and divided into three groups. The dentinal cavities in each group were irrigated with 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), or normal saline for 30 min. After that, irrigation solutions were removed using a cotton pellet. Each group was then randomly divided into two subgroups according to the cavity-filling materials (ProRoot mineral trioxide aggregate [MTA] and RetroMTA). The color assessments were performed before filling the cavities and 1 month and 6 months after filling the cavities. Data were analyzed with two-way ANOVA. The level of statistical significance was set at P < 0.05. The effect of irrigation solution on the color change of calcium silicate-based materials was not statistically significant at none of the time intervals (P = 0.334 and P= 0.252, respectively, for ProRoot MTA and RetroMTA). ProRoot MTA caused a significantly higher color change compared with RetroMTA exposed to different irrigation solutions at each time interval (P < 0.001). Color change of both materials exposed to each irrigation solution significantly increased over time (P < 0.05). Under the condition of this ex vivo study, irrigation of dentin with NaOCl and CHX and then removing the excess solution might be ineffective in increasing the tooth color change potential of either bismuth oxide or zirconium-containing calcium silicate-based materials. Furthermore, calcium silicate-based material, which contained bismuth oxide, caused higher tooth discoloration.