Silicate Cement Research Articles

Pull-Out Bond Strength of Titanium Post Cemented with Novel Fast-Setting Calcium Silicate Cement.

Objective:The aim of this study was to compare the pull-out bond strength of prefabricated titanium posts cemented with novel fast-setting calcium silicate, zinc phosphate, or glass ionomer cements.Methods:Sixty extracted human maxillary incisors were selected and received root canal treatment. Post space was prepared for titanium ParaPost XP size 5 (diameter=1.25 mm). The posts were cemented using novel calcium silicate cement, zinc phosphate cement, or glass ionomer cement (n=20). Specimens were stored in phosphate-buffered saline for 4 weeks. Subsequently, the posts were subjected to axial tensile force until bond failure. Data were analyzed by one-way ANOVA followed by multiple comparisons.Results:The posts cemented with novel calcium silicate cement (10.5±3.8 MPa) demonstrated significantly higher bond strength than zinc phosphate (8.0±2.6 MPa) and glass ionomer cements (8.0±2.7 MPa) (P<0.05).Conclusion:Within the limitation of the study, the pull-out bond strength of titanium post cemented with novel calcium silicate cement in endodontically treated teeth was superior to zinc phosphate and glass ionomer cements.

Expression of Matrix Metalloproteinases-8 and Myeloperoxidase in Pulp Tissue after Pulpotomy with Calcium Silicate Cements

Objective: To evaluate the pulp tissue of rat molars after pulpotomies with mineral trioxide aggregate (MTA), BiodentineTM (BDT) and calcium hydroxide (CH) mixed with sterile saline solution (24 hours, 72 hours, 7 days and 15 days), through correlating MPO activity with active neutrophils and MMP8 activity with tissue remodeling. Material and Methods: Thirty-eight Wistar rats were randomly distributed into groups (control, I (MTA gray), II (BDT), and III (CH)) and subdivided according to the study period of 24 hours, 72 hours, 7 days or 15 days after pulpotomy. MMP8 activity was assessed through fluorescence technique, and MPO activity was determined using the MPO assay. Results: A gradual decrease of MPO and MM8 activity occurred in the group MTA over the experimental periods (p<0.05). Groups BDT and CH exhibited an increase in the activity at 7 and 15 days (p<0.05). Conclusion: MTA demonstrated a decrease in the values of MPO e MMP8. BDT and CH showed high neutrophilic and collagenase activity over the experimental periods.

Interface between calcium silicate cement and adhesive systems according to adhesive families and cement maturation.

ObjectivesThis study aimed to evaluate the interface between a calcium silicate cement (CSC), Biodentine and dental adhesives in terms of sealing ability.Materials and MethodsMicroleakage test: 160 standardized class II cavities were prepared on 80 extracted human molars. The cavities were filled with Biodentine and then divided into 2 experimental groups according to the time of restoration: composite resin obturation 15 minutes after Biodentine handling (D0); restoration after 7 days (D7). Each group was then divided into 8 subgroups (n = 5) according to the adhesive system used: etch-and-rinse adhesive (Prime & Bond); self-etch adhesive 2 steps (Optibond XTR and Clearfil SE Bond); self-etch adhesive 1 step (Xeno III, G-aenial Bond, and Clearfil Tri-S Bond); and universal used as etch-and-rinse or self-etch (ScotchBond Universal ER or SE). After thermocycling, the teeth were immersed in a silver nitrate solution, stained, longitudinally sectioned, and the Biodentine/adhesive percolation was quantified. Scanning electron microscopic observations: Biodentine/adhesive interfaces were observed.ResultsA tendency towards less microleakage was observed when Biodentine was etched (2.47%) and when restorations were done without delay (D0: 4.31%, D7: 6.78%), but this was not significant. The adhesives containing 10-methacryloyloxydecyl dihydrogen phosphate monomer showed the most stable results at both times studied. All Biodentine/adhesive interfaces were homogeneous and regular.ConclusionsThe good sealing of the CSC/adhesive interface is not a function of the system adhesive family used or the cement maturation before restoration. Biodentine can be used as a dentine substitute.

Technoeconomic Study of Belitung Kaolin as Import Substitution Material in Fiber Cement Board Production

Cement board that commonly used as raw material for cheap housing component is calcium silicate cement board (fiber cement boards). However, the clay used as raw material for cement boards is still imported. In 2019, imported clay used for construction industry in Indonesia amounted to 57,000 tonnes per year with a transaction value of more than US $ 38 million. On the other hand, Indonesia, especially the province of Bangka Belitung, has a value of kaolin resources of 376,687,532 tons. Baristand Banjarbaru has successfully applied Belitung kaolin as a substitute for imported clay in cement board production. The physical properties of cement board made of kaolin Belitung were not significantly different from cement board made of imported clay.Therefore, Belitung kaolin has the potential to become a substitute for imported clay in cement board production and can be increased in terms of production scale so a techno-economic study is needed. Technoeconomic study had analyzed with the assumptions for a cement board production capacity of 100 tons / day, an investment age of 5 years, an initial investment of 0 for imported clay as raw material and 13,167,000,000 for kaolin as raw material or equivalent to 30% of sales. With the selling price of cement board Rp.55,000 / kg, the NPV of Belitung kaolin is 86,071,631,216.30 and the NPV of imported clay is 77,604,584,262.66. These results indicate that the cement board production business using Belitung kaolin as raw material is feasible to develop.

The Influence of New Silicate Cement Mineral Trioxide Aggregate (MTA Repair HP) on Metalloproteinase MMP-2 and MMP-9 Expression in Cultured THP-1 Macrophages.

The aim of the present study was to investigate the new silicate cement mineral trioxide aggregate (MTA Repair HP) with respect to its effect on the inflammation process involving the tooth and periodontal tissues. The composition of MTA Repair HP was supplemented with plasticizer agents which can have a negative effect on the modulation of tooth inflammation. The silicate-based material in question is widely used in regeneration of the pulp-dentin complex, treatment of perforations of various locations in the tooth, as well as in surgical treatment of the complications of periapical tissue. The improved bioceramic restorative cement can affect the expression of metalloproteinases MMP-2 and MMP-9 in monocytes/macrophages involved in modulation of inflammation and regenerative processes of the tooth and periodontal tissues. The novel aspect of the present study lies in the application of the model of THP-1 monocyte/macrophage and applying the biomaterial in direct contact with the cells. Hence, it provides a representation of clinical conditions with respect to regenerative pulp and periodontal treatment with the use of MTA Repair HP. A lack of macrophage activation (as measured with flow cytometry) was found. Moreover, the study identified a lack of expression stimulation of the studied metalloproteinases (with the use of Western blotting and fluorescent microscopy). Similarly, no increase in MMP-2 and MMP-9 concentration was found (measured by ELISA method) in vitro when incubated with MTA Repair HP. Based on the results it can be concluded that new MTA Repair HP does not increase the inflammatory response in monocytes/macrophages associated with the activity of the described enzymes. It can also be speculated that they do not affect the process of dentin regeneration in which MMP-2 and MMP-9 play significant roles.

The effect of chlorhexidine and dimethyl sulfoxide on long-term sealing ability of two calcium silicate cements in root canal

ObjectivesTo evaluate the long-term effect of chlorhexidine (CHX) and dimethyl sulfoxide (DMSO) on the sealing ability and biomineralization of two different calcium silicate cements (CSC) in root canal. MethodsSixty human third molar root canals were obturated with ProRoot MTA or Biodentine. Before obturation the canals were irrigated with saline (control), 2% CHX or 5% DMSO. Microleakage was tested after three days and after six months. After additional six months (12 months after root filling) the roots were cut into 2 mm thick dentine discs. The discs were stored in artificial saliva for one year. The bond strength was measured with the push-out method, and the failure mode was evaluated with a stereomicroscope. The most apical disc of each tooth was used for Vickers hardness test. ResultsNo significant differences between the groups was found in initial microleakage. The leakage increased significantly during the 6-month storage in all groups except in Biodentine-CHX group and Biodentine-DMSO group. CHX and DMSO irrigation significantly increased the leakage with ProRoot MTA with time, but there was no statistically significant difference compared to the ProRoot MTA-control group at six months’ time point. CHX significantly reduced the push-out bond strength of ProRoot MTA. With Biodentine irrigation with CHX or DMSO resulted with significantly higher push-out strength compared to the Biodentine control group. Fracture analysis showed statistically significant difference in the distribution of the fractures between the groups, but neither CHX nor DMSO change the fracture pattern statistically significantly. With Vickers hardness test ProRoot MTA with and without DMSO as the final irrigant showed significantly higher dentin hardness than any Biodentine-group. SignificanceConsidering that aging increased the leakage in all groups except with Biodentine-DMSO and the differences in the push-out strength and surface microhardness data, it appears that the time-related biomineralizing effect of MTA and Biodentine does not improve sealing to dentin. CHX significantly reduced ProRoot MTA bond strength and increased pure adhesive failures with both cements.

Influence of sodium nitrate on the phases formed in the MgO-Al2O3-SiO2-H2O system

The incorporation of sodium and aluminium in magnesium silicate hydrate phases (M-S-H), possible binding phases in magnesium silicate cement, was investigated. Magnesium alumino silicate hydrate containing sodium (M-A-S-H N samples) were synthesized in batch experiments with NaNO3 ~ 100 mmol/L at Mg/Si ratios equal to 0.8 and 1.2, and Al/Si ratios of 0, 0.1 and 0.2, and equilibrated at 20 and 50 °C. Thermogravimetric analysis (TGA), X-rays diffraction (XRD), 29Si MAS NMR data showed that M-A-S-H phases formed, with a similar structure as M-S-H. 27Al and 23 Na MAS NMR data showed that only little sodium was sorbed, while aluminium was possibly incorporated in both tetrahedral and octahedral sites of M-A-S-H. We found evidence that the presence of sodium nitrate led to the formation of hydrotalcite-like phase probably containing NO3− and possibly to the trace formation of hydrated alumino-silicate containing sodium: N-A-S-H gel. These minor phases limited the aluminium uptake by M-S-H at higher Al contents (Al/Si = 0.2).

Comparative evaluation of volumetric changes of three different retrograde calcium silicate materials placed under different pH condititions

BackgroundThe present study aimed to compare the volumetric changes of three calcium silicate cements after retrofilling and placing under different pH conditions via micro-computed tomography (micro-CT) scan.MethodsForty-two extracted human single-rooted teeth were randomly assigned to three groups according to the retrofilling materials used (Biodentine, Endocem MTA, and ProRoot MTA). Each group was divided into two subgroups according to the setting condition. The teeth in one group were immersed in normal saline for 5 days at room temperature, and the teeth in the other group were immersed in butyric acid (pH = 5.4) for 5 days at room temperature. The volume ratios of the retrofilling material were calculated via micro-CT imaging.ResultsThe volume ratios of the Biodentine and Endocem MTA groups were significantly different between the two setting environment, and these groups had significantly lower filled volume ratio (Vf, %) in the acidic environment than in the saline environment (pH = 5.4). Meanwhile, the volume ratio of the ProRoot MTA group did not significantly differ between the two setting environments. All materials under the acidic setting condition had relative radiolucency in the area in contact with the acidic solution.ConclusionThe Vf ratio of the Biodentine and Endocem MTA cements was significantly lower in the acidic environment than in the saline environment. No statistically significant difference was observed in the Vf ratio of ProRoot MTA between the two setting environments.

Colour and chemical stability of bismuth oxide in dental materials with solutions used in routine clinical practice.

Bismuth(III) oxide is included as a radio-opacifier in dental materials, including hydraulic silicate cements, the material of choice for several endodontic procedures. It has been implicated in tooth discoloration after contact with endodontic irrigants, in particular NaOCl solution, To date, there has been no work on the chemistry: all reports have been of clinical findings only. The purpose now was to report the reactions leading to colour change from Bi2O3 in contact with solutions used in routine endodontic practice. Ten-gram portions of Bi2O3 were immersed in either water, NaOH, NaCl, NaOCl or HCl solution, either in the dark or exposed to visible light, and samples retrieved at 1, 4, 12 and 24 weeks. After washing, these were exposed to either added CO2 or not, for 1 week while drying, and under the same dark or light conditions. Changes in appearance were monitored by photography and colour measurement, and chemically by X-ray diffraction and Fourier-transform infrared spectroscopy. 24-week material was studied using electron paramagnetic resonance and Raman spectroscopy; NaOCl-treated material was also examined by scanning electron microscopy. With water, NaCl and NaOH, bismuth subcarbonate was formed. With or without added carbon dioxide, discoloration occurred from pale yellow to light brown when exposed to light, and to a lesser extent in the dark, intensifying with time. In contrast, exposure to NaOCl rapidly formed a dark brown-black sodium bismuthate. With HCl, white BiOCl was formed. Bi2O3 is not at all inert in this context as is commonly believed, denying its principle of use. Previously unreported solution-mediated reaction occurs readily even in water and NaCl solution, forming new compounds that discolour. In contact with NaOCl sodium bismuthate is formed; severe darkening occurs rapidly. The reactivity is such that Bi2O3 is not indicated for dental materials and should be withdrawn from use.

Preparation of tricalcium silicate and investigation of hydrated cement

Tricalcium silicate cement (TSC) has been widely used in dental materials because of its self-setting behavior, good bioactivity, biocompatibility, osteoinductivity, and antibacterial effect. Tricalcium silicate (C3S) powder was prepared by Pechini technique with a calcining temperature of 1300 °C for 3 h. The influence of liquid/powder (L/P) rate on the setting time and the mechanical property of TSC was studied. Characterization methods including XRD, FTIR, SEM-EDS, TEM, and ICP-AES were utilized to study the properties of C3S powder and its hydrated cement. The bioactivity and biocompatibility of the cement were investigated by soaking test and cell culture, respectively. The results show that the L/P rate plays an important role in the setting time and the compressive strength of TSC. The surface of TSC was covered by hydroxyapatite deposition during the immersion experiment and the cells attachment on the surface of TSC was well, which indicated that TSC has good bioactivity and biocompatibility. In addition, TSC has excellent antibacterial properties against Staphylococcus aureus. In conclusion, TSC is a promising candidate for root canal filling materials.

The Effect of Biodentine Maturation Time on Resin Bond Strength When Aged in Artificial Saliva.

Biodentine is a calcium silicate cement (CSC) that has been broadly applied in vital pulp therapy. The quality of the Biodentine-composite bond has a significant effect on the longevity of the definitive restoration. The aim of this study is to investigate the shear bond strength (SBS) between Biodentine and composite restoration at different maturation times of Biodentine aged in artificial saliva. Fifteen Biodentine discs were allocated into three groups (n = 5) based on the timeframe of performance of composite restoration: immediate (after 12 min), after 14 days, and after 28 days of Biodentine maturation. Total etch and rinse adhesive system and bulk-fill regular resin composite were used. The shear bond strength and the failure pattern were assessed. One-way ANOVA with the Bonferroni post hoc test was applied for statistical analysis at p < 0.05. The highest (32.47 ± 8.18 MPa) and the lowest (4.08 ± 0.81 MPa) SBS values were recorded for 14 days and 12 min groups, respectively. Significant statistical differences were reported among the groups, and a high statistically significant difference was found between the immediate group and the other groups. Adhesive failure patterns were evident in all groups. More clinically acceptable bond strength between the Biodentine and overlaid composite restoration is at 14 days after Biodentine maturation. Delaying the coverage of Biodentine later than 14 days may significantly reduce the SBS. Using the artificial saliva as an aging medium may affect the SBS between Biodentine and composite material.

Study on the optimum grouting materials and their performance in the TBM tunnel collapse reinforcement project

Considering the water inrush and collapse accident involving a tunnel boring machine (TBM) in a tunnel of the Qingdao Metro Line 1, the difficulties in grouting reinforcement in the collapse area were analyzed in order to avoid the adverse effects of grouting on the TBM equipment. The zoning governance method was chosen to solve these problems. The performance requirements of grouting materials for different areas were analyzed, after which the key properties of the materials were tested and the optimum was determined. For the water gushing area, polyurethane material was the common option, whereas for the shield area, a new high-expansion grouting material with low-strength was chosen. For the cutter head area, cement silicate grout modified by adding bentonite and quick-setting additives was tested, with the resulting material showing low strength and a quick-setting property. For the tunnel vault area, cement silicate grout and polymer-modified material were deemed suitable. After testing its viscosity change, we found that the polymer-modified material had a viscosity stabilization period. Thus, it was subsequently used at the key area. The selection of materials could reduce the consolidation risk of cutter disc and shield shell in the TBM. The research findings provide useful reference for similar projects.

Alkali-Activated Slag cement: Alternative Adhesives for CFRP Sheets Bonded to Concrete at Elevated Temperatures

The properties and microstructures of alkali-activated slag cement (AASC) exposed to 20~1200°C were probed in this paper. The aim is to develop an eco-friendly fireproof high-strength adhesive with an optimum ratio and evaluate its usability for CFRP sheets bonded to concrete. The blast furnace slag and fly ash were employed as source materials (activated by potassium silicate, NaOH and Portland cement). The effects of slag content, activator nature and heating temperature on the compressive or bond properties were analyzed. The microstructures of the AASC exposed to different high temperatures were studied by two different techniques, including SEM and XRD analyses. The effects of temperature on the mechanical properties of AASC were first rising then descending, and the basic reason for the degradation of macro-mechanical properties is the deterioration of AASC microstructure. It is proved that AASC has comparable reinforcing effects as those of organic epoxy matrix.

Preparation and properties of tristrontium aluminate as an alternative component of mineral trioxide aggregate (MTA) cement.

This study evaluated tristrontium aluminate (S3A) and its viability as a component for tricalcium silicate (C3S) cements. The properties of S3A, C3S, and S3A/C3S mixtures were evaluated in terms of setting time, compressive strength, flowability, and radiopacity. X-ray diffraction (XRD) pattern verified the powder synthesized in the laboratory as S3A, consequently, confirming the preparation method. S3A exhibited the lowest setting time, followed by C3S and S3A/C3S mixtures. Compressive strength of C3S was significantly higher than S3A. The S3A/C3S mixture showed comparable compressive strength to C3S for 1-day post initial mixing. There was no significant difference in flowability between S3A/C3S and mineral trioxide aggregate (MTA). S3A showed comparable radiopacity to MTA, whereas that of the S3A/C3S mixture was significantly lower comparatively; however, it achieved sufficient radiopacity (3 mm aluminum thickness equivalent). Further studies are needed to improve the manufacturing process of S3A and evaluate the bioactive effect of strontium.

Spectrophotometric Analysis of Coronal Tooth Discoloration Induced by Tricalcium Silicate Cements in the Presence of Blood

IntroductionNew tricalcium silicate cements have been shown to induce less coronal discoloration. The purpose of this in vitro study was to evaluate the degree of color change induced by various silicate materials in the presence and absence of blood. MethodsOne hundred human extracted anterior single-canal teeth were sectioned to standardized root lengths, accessed, and instrumented. Eight random experimental groups and 2 control groups were created wherein specimens were filled with experimental materials below the buccal cementoenamel junction as follows: EndoSequence RRM putty (Brasseler USA, Savannah, GA), EndoSequence RRM fast set putty (Brasseler USA), Biodentine (Septodont, Saint-Maur-des-Fossés, France), and white mineral trioxide aggregate (Dentsply Sirona, York, PA) either with the presence or absence of blood. Blood-only and saline-only samples were used for the positive and negative controls. After incubation in 100% humidity at 37°C, color changes were evaluated with a spectrophotometer (Ocean Optics, Dunedin, FL) on days 0, 30, 60, and 180 after material placement. Data were transformed into Commission International de I'Eclairage's L∗a∗b color values, and corresponding ΔE values were calculated. The 1-way analysis of variance test was performed for statistical analysis. ResultsDiscoloration was observed in all specimens in the presence of blood. There was no statistical significance when comparing different materials in contact with blood. Intragroup observation at various time points, Biodentine, and EndoSequence RRM fast set putty showed significant difference between the presence and absence of blood at 180 days (P < .05). ConclusionsContamination with blood of tricalcium silicate materials has the potential to cause coronal tooth discoloration.

Physicochemical, antimicrobial, and biological properties of White-MTAFlow.

To evaluate a new material containing tantalum oxide as an alternative radiopacifier, and a water-based gel for hydration, in comparison with two calcium silicate-based cement: ProRoot MTA and Biodentine. ProRoot MTA (Dentsply), Biodentine (Septodont), and a new hydraulic calcium silicate cement White-MTAFlow (Ultradent) (in 'thin' consistency) were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). The interaction with dentin was also assessed using SEM and EDS. Physical and chemical properties radiopacity, setting time, linear flow, volumetric central filling, and lateral flow, pH, and volume change were investigated together with the color luminosity (L) and color change (ΔE). The agar diffusion and direct contact antimicrobial activity, and methylthiazolyldiphenyl-tetrazolium-bromide (MTT) cytotoxicity using human fibroblast cells were also evaluated. Data were statistically analyzed at a 5% significance level. All materials were composed of tricalcium and dicalcium silicate but had different radiopacifiers, and calcium hydroxide (portlandite) deposition was detected in XRD analysis. White-MTAFlow exhibited radiopacity values in accordance with ISO standard, and the longest setting time. The water-based gel provided the highest linear flow, a comparable cavity central filling, and the highest groove-lateral flow in the volumetric flow analysis. White-MTAFlow exhibited an alkalinity reduction, and Biodentine, a progressive increase of pH values after 28 days. However, similar volume loss for White-MTAFlow was assessed in comparison to Biodentine after the 28-day immersion. White-MTAFlow showed the highest L value (91.5), and ProRoot MTA the lowest (78.1) due to dentin staining caused by bismuth migration. None of the materials exhibited inhibition halos against the tested bacteria, and similar turbidity values were obtained after 48 h in direct contact with E. faecalis, indicating an upregulation to bacterial growth. White-MTAFlow showed MTT cytocompatibility similarly to the control group. White-MTAFlow in 'thin' consistency presents comparable physicochemical, biological, and antimicrobial properties to ProRoot MTA and Biodentine, and does not cause color alteration in dentin. White-MTAFlow is a suitable material for use as reparative endodontic cement. Further studies considering its biocompatibility are necessary.

Effects of nano-SiO2 particles on physio-chemical properties of bioactive tricalcium silicate cements

The aim of this study is to investigate the effect of nano-SiO2 (NS) particles addition on physico-mechanical properties, microstructure evolution, and apatite-formation ability of bioactive tricalcium silicate (TCS). Furthermore, the concentrations of calcium (Ca), silicon (Si), and phosphorus (P) in phosphate buffer saline solution (PBS) after immersion of TCS-based cements with diverse additions of NS were also evaluated. The results revealed that the setting time of cement pastes lowered significantly from 72 to 51 min with the doping content of NS from 0 to 5%. The compressive strength and Vickers micro-hardness (HV) of cements with addition of 3% NS after setting for 7 days were significantly higher than those of TCS cements without NS. Furthermore, the cements could induce hydroxyapatite (HA) formation on their surfaces in PBS. The storage solution of TCS-based cements was alkaline, and the pH values changed from 12.26 to 12.65. There were no significant differences about Ca, Si, and P concentrations of PBS after immersion of TCS cement with the addition of 3% NS as compared with doping 0% NS. Our results indicated that TCS cement with addition of 3% NS had enhanced physico-mechanical properties and good HA-formation ability and may make it a potential choice for using as a novel dental material.

In vitro and in vivo osteogenesis of gelatin-modified calcium silicate cement with washout resistance.

The purpose of this study was to evaluate the physicochemical properties and the in vitro and in vivo osteogenesis of the newly developed calcium silicate containing 5wt% gelatin (CSG) cement compared with calcium silicate (CS) and calcium sulfate hemihydrate (CSH) cements. In addition to the phase composition and microstructure, washout resistance, setting time, and diametral tensile strength of the bone cements were also performed. In vitro examination of cell growth, differentiation, and mineralization were performed with macrophage cell line (RAW 264.7), MG63 human osteoblast-like cells, and human mesenchymal stem cells (hMSCs). The mini-pig model with mandibular alveolar bone defect was used to assess the in vivo function of cement. Histological and histomorphometric assessments were performed at 6 and 12weeks after implantation. The results indicated that the CS and CSG powders were mainly composed of poorly crystalline β-dicalcium silicate, and the irregular CSH powders had a highly crystalline phase. After setting, the product of CS and CSG was calcium-silicate-hydrate gel and CSH exhibited a plate-like gypsum crystal structure. The setting time of CS, CSG, and CSH was 19, 35, and 10min, respectively. Gelatin effectively improved the washout resistance and diametral tensile strength of CS from 2.4MPa to 3.4MPa, while CSH had no washout resistance and its strength was 7.6MPa. The osteogenic activity of MG63 and hMSC cells on the CSG cement surface was consistently shown to be significantly higher than that on the CSH cement surface. Interestingly, CS and CSG cements exhibited lower macrophage expression compared to CSH cements. Twelve week after implantation, the amount of new bone in the defect area of the CS group was slightly higher than that of the CSG and CSH groups. It is concluded that CSG cement had improved anti-washout performance, favorable osteogenesis in vitro and in vivo, which was beneficial for clinical application.

Solubility of Calcium Silicate Based Cements – a Comparative Study

Abstract Calcium silicate based cement is a group of biomaterials, based on Portland cement. Its physicochemical properties such as solubility are of the utmost importance. It should have low solubility in tissue fluid since the dissolution of materials may lead to treatment failure. The aim of this study is to evaluate the solubility of five calcium silicate cements after being placed in distilled water for a period of 28 days. Material and methods: The purpose of this study was to compare solubility of a four new calcium silicate-based cements, such as: gray MTA Angelus; white MTA Angelus; BioAggregate and Biodentine with conventional mineral trioxide aggregate White ProRoot. Solubility is evaluated using standardized samples of materials, which are weighed before and after 28-day immersion in distilled water. Results: The lowest solubility is found at White ProRoot and the significantly highest solubility – at Biodentine.

Preclinical effectiveness of an experimental tricalcium silicate cement on pulpal repair.

To investigate the pulpal repair potential of an experimental zirconium-oxide containing tricalcium-silicate cement, referred to as 'TCS 50'. The effect of TCS 50 on viability, proliferation, migration, and odontoblastic differentiation of human dental pulp cells (HDPCs) was assessed using XTT assay, in-vitro wound healing assay and RT-PCR, respectively. Additionally, the pulp-capping potential was evaluated using a vital human tooth model. Statistical analysis was performed using non-parametric Kruskal-Wallis test and post-hoc test (Mann-Whitney U test). The tests were performed at a significance level of α=0.05. The effect of TCS 50 towards HDPCs was dose dependent. Undiluted TCS 50 extract showed no immediate adverse impact on cell viability (p>.05); however, it significantly inhibited proliferation and migration of HDPCs (p<.05). A 25% diluted TCS 50 extract showed no significant effect on cell viability, proliferation or migration (p>.05), and it significantly enhanced odontoblastic differentiation of HDPCs (p<.05). In pulps capped with TCS 50 for both 2 and 4weeks, H&E staining revealed a normal morphology of pulp tissue; mineralized foci with cellular components entrapped in the matrix were formed underneath the exposure site. Collagen I expression was weak within the matrix of mineralized foci, while the expression of nestin was positive for entrapped cellular components within the mineralized foci, indicating that the formed mineralized foci corresponded to an initial form of reparative dentin formation. TCS 50 is capable of generating an early pulp-healing reaction and therefore could serve as a promising pulp-capping agent.