Ex vivo biocompatibility tests of regular and white forms of mineral trioxide aggregate

Comparison of bioactive material failure rates in vital pulp treatment of permanent matured teeth - a systematic review and network meta-analysis

Mineral Trioxide Aggregate (MTA) is the gold standard for vital pulp treatment (VPT), but its superiority over novel calcium silicate-based cements in permanent teeth lacks systematic evidence. This study aimed to compare the efficacy of these materials in VPT through a network meta-analysis. A systematic search was conducted in MEDLINE, EMBASE, Cochrane Library, and Web of Science until January 20, 2024. The inclusion criteria were randomized controlled trials involving VPT with biomaterials and reversible or irreversible pulpitis diagnoses in mature permanent teeth. The primary outcome was the odds ratio (OR) of failure rates with 95% confidence intervals. In the 21 eligible trials, failure rates were significantly higher with calcium-hydroxide than MTA at six (OR 2.26 [1.52-3.36]), 12 (OR 2.53 [1.76-3.62]), and 24 months (OR 2.46 [1.60-3.79]). Failure rates for Totalfill at six (OR 1.19 [0.55-2.58]) and 12 months (OR 1.43 [0.71-2.92]), and Biodentine at six (OR 1.09 [0.66-1.78]), 12 (OR 1.21 [0.74-1.96]), and 24 months (OR 1.47 [0.81-2.68]) were not significantly different from MTA. The results were similar in the direct pulp capping subgroup, whereas, in the partial and full pulpotomy subgroup, there was not enough evidence to achieve significant differences. MTA, Biodentine, and Totalfill are the most efficient materials for VPT. However, calcium-hydroxide-based materials are not recommended in VPT.

Comparative evaluation of shear bond strength of calcium silicate-based liners to resin-modified glass ionomer cement in resin composite restorations - a systematic review and meta-analysis

Purpose The aim of this systematic review was to evaluate the difference in shear bond strength between calcium silicate-based liners to resin-modified glass ionomer cement (RMGIC) in resin composite restorations.Materials and methods The protocol was registered in PROSPERO following which primary research was carried out on Medline, Scopus and Cochrane library. To assess the risk of bias, a customised tool was used. Among the 194 records retrieved from the databases, only ten articles qualified for qualitative and quantitative synthesis after meeting all the requirements of the eligibility criteria. Covidence software was used to record the decisions. Studies published until 31 March 2021 were taken up for the review. The articles showed a low-to-moderate risk of bias. I2 test was used to check the percentage variation due to heterogeneity.Results RMGIC showed a higher shear bond strength value compared to the three calcium silicate liners MTA, Biodentine and TheraCal LC. However, TheraCal LC and MTA showed better bond strength than Biodentine. Cohesive failure was seen predominantly in liners followed by adhesive failure. RMGIC shows mixed mode of failure in some studies.Conclusions RMGIC is preferred over calcium silicate-based materials as the liner to be used under resin composite restorations. Among calcium silicate-based materials, TheraCal LC showed a better bond strength value. The mode of failure was predominantly cohesive in all the liner groups in majority.

Antimicrobial Action, Genotoxicity, and Morphological Analysis of Three Calcium Silicate-Based Cements

This study is aimed at evaluating five mineral oxides (5MO), mineral trioxide aggregate repair high plasticity (MTA HP), and mineral trioxide aggregate (MTA) in relation to the antimicrobial action over Porphyromonas gingivalis, Porphyromonas endodontalis, Parvimonas micra, Fusobacterium nucleatum, and Prevotella intermedia; the genotoxicity over mouse macrophage (RAW 264.7) and osteoblast (Mg-63) cultures; and the morphological analysis using scanning electron microscopy (SEM) analysis (50 k and ×100 k). Sodium hypochlorite (NaOCl), calcium hydroxide, and saline solution were used as control groups in the different analysis. All data were submitted to a normality test and then analyzed with one-way ANOVA, Tukey, and Kruskal-Wallis and Dunn tests, considering α ≤ 0.05 significance level. It was found that over P. gingivalis and P. endodontalis, there was no a significant difference between the calcium silicate-based cements (CSC) and the control group of saline solution, and only 5MO was similar to the NaOCl group. However, over P. micra, all groups were effective and showed a statistically significant difference compared to the saline solution group. Conversely, none of the groups were effective over F. nucleatum and P. intermedia, except of the NaOCl group. There was a significant difference between 5MO and MTA groups in comparison with NaOCl and MTA HP over osteoblasts and macrophages after 24 hours. SEM images showed small irregular particles interspersed with some elongated needle-like particles and small irregular particles with some larger particles as well as elongated particles. It was concluded that 5MO, MTA, and MTA HP have effective antimicrobial action over P. micra. However, only 5MO is effective over P. gingivalis and P. endodontalis. Besides, 5MO and MTA are not genotoxic over mouse macrophage (RAW 264.7) and osteoblast (Mg-63) cultures.

An In vitro Study to Assess the Effectiveness of the Shear Bond Strength of Mineral Trioxide Aggregate with Different Adhesive Systems

Purpose of the Study

Mineral trioxide aggregate (MTA) is a biocompatible material and has excellent sealing ability. It is proved and claimed that it provides double seal due to its physical sealing ability as well as ability to induce cementogenesis that provides biological seal.

Aim and Objectives

The aim of the study was to assess the shear bond strength of MTA with three different types of adhesive systems: (1) self-adhering flowable composite, (2) etch and rinse (ER) adhesive system, and (3) self-etch (SE) adhesive system.

Materials and Methods

Ninety MTA specimens were prepared using cylindrical acrylic blocks, having a central cavity with 2 mm depth and 4 mm diameter. MTA was mixed and placed in the prepared cavity and was covered with moist cotton pellet and temporary filling material (Cavit). They were further divided into three groups which were further divided into two subgroups. After the bonding agents was applied, the composite resin was placed over the MTA surface. The specimens were then tested for shear bond strength; statically analysis was done.

Result

After 24 h, the mean value of ER group was found to be significantly higher than SE and the self-adhering composite groups. Among the 45 min groups, there was no significant difference observed.

Conclusion

In single visit, after 45 min, self-adhering flowable can be used successfully as a final restorative material in place of conventional flowable composite without using any alternative adhesive system over MTA.

Genotoxicity of root canal sealers: a literature review

OBJECTIVES

Root canal sealers are widely used worldwide in endodontics to prevent reinfection and growth of surviving microorganisms. Considering the strong correlation between genetic damage and carcinogenesis, evaluation of genotoxicity induced by endodontic sealers is recommended for elucidating the true health risks to patients and professionals. The purpose of this article was to provide a comprehensive review of studies involving genotoxicity analysis of endodontic sealers and the used methodologies.

MATERIALS AND METHODS

A literature search was made in PubMed using the following combination of words "genotoxicity," "mutagenicity," "endodontic sealers," and "root canal sealers." A total of 39 articles with genotoxicity studies were selected for the present study.

RESULTS

Sealers have been ranked in decreasing order of their genotoxicity as: ZOE sealers > GIC sealers > S sealers > ER sealers > MR sealers > Novel sealers > CH sealers > CS sealers.

CONCLUSIONS

All published data showed some evidence of genotoxicity for most of the commercial root canal sealers; however, contradictory results were found, mainly for AH Plus, the most studied sealer.

CLINICAL RELEVANCE

The information provided would direct the endodontists to use the less genotoxic materials in endodontic treatment in a way to reduce DNA damage promoting oral healthcare.

Examination of Calcium Silicate Cements with Low-Viscosity Methyl Cellulose or Hydroxypropyl Cellulose Additive

The purpose of this study was to improve the operability of calcium silicate cements (CSCs) such as mineral trioxide aggregate (MTA) cement. The flow, working time, and setting time of CSCs with different compositions containing low-viscosity methyl cellulose (MC) or hydroxypropyl cellulose (HPC) additive were examined according to ISO 6876-2012; calcium ion release analysis was also conducted. MTA and low-heat Portland cement (LPC) including 20% fine particle zirconium oxide (ZO group), LPC including zirconium oxide and 2 wt% low-viscosity MC (MC group), and HPC (HPC group) were tested. MC and HPC groups exhibited significantly higher flow values and setting times than other groups (p < 0.05). Additionally, flow values of these groups were higher than the ISO 6876-2012 reference values; furthermore, working times were over 10 min. Calcium ion release was retarded with ZO, MC, and HPC groups compared with MTA. The concentration of calcium ions was decreased by the addition of the MC or HPC group compared with the ZO group. When low-viscosity MC or HPC was added, the composition of CSCs changed, thus fulfilling the requirements for use as root canal sealer. Calcium ion release by CSCs was affected by changing the CSC composition via the addition of MC or HPC.

Shear bond strength of a novel light cured calcium silicate based-cement to resin composite using different adhesive systems

The shear bond strength (SBS) of TheraCal LC to resin composite was evaluated in comparison to Mineral trioxide aggregate (ProRoot MTA) and conventional glass ionomer cement (GIC) using two adhesive systems. A hole was prepared in 90 acrylic blocks (6 mm diameter, 2 mm deep) then filled with TheraCal LC, MTA or Fuji IX (n=30/group). Each group was bonded with either an etch and rinse or 1-step self-etch adhesive. Filtek Z250 composite was bonded to each capping material. Bond strength was tested in a universal testing machine, and data were analyzed using 2-way ANOVA and Duncan's Multiple range test (p<0.05). TheraCal LC displayed the highest SBS (p<0.001). MTA bonded with the 1-step self-etch adhesive showed the lowest SBS (p<0.001), while SBS of TheraCal LC and Fuji IX did not differ between either adhesive (p>0.05). TheraCal LC is the preferred choice in pulp capping procedures when using resin composite restorations.

The shear bond strength of MTA with three different types of adhesive systems: An in vitro study

AIM

To evaluate the shear bond strength of MTA with three different types of adhesive systems- self-adhering flowable composite, etch and rinse adhesive system and self etch adhesive system.

METHODOLOGY

MTA specimens (n = 60) were prepared using cylindrical acrylic blocks, having a central cavity with 4 mm diameter and 2 mm depth. MTA was mixed and placed in the prepared cavity, and was covered with a moist cotton pellet and temporary filling material. The specimens were divided into 3 groups which were further divided into 2 sub-groups (45 Minutes and 24 hours). After the application of bonding agents composite resin was placed over the MTA surface. The specimens were tested for shear bond strength and readings were statically analyzed.

RESULT

After 24 hrs the mean value of etch and rinse group was significantly higher than self etch and the self adhering composite groups. Among the 45 minutes groups there were no significant difference.

CONCLUSION

In single visit after 45 minutes self adhering flowable can be used successfully as a final restorative material in place of conventional flowable composite without using any alternative adhesive system over MTA.

Bond strength of adhesive systems to mineral trioxide aggregate with different time intervals

INTRODUCTION

The aim of this study was to compare the shear bond strengths of various adhesive systems to white mineral trioxide aggregate (WMTA) with different time intervals.

METHODS

Two hundred cylindrical acrylic blocks with a hole (4-mm diameter and 2-mm height) were prepared. The holes were filled with WMTA, and the specimens were allocated into 5 groups. Forty specimens were stored for 4, 24, 48, 72, and 96 hours at 37°C and 100% humidity. Each group was divided into 4 subgroups: group 1, All-Bond SE (Bisco Inc, Schaumburg, IL); group 2, All-Bond 3 (Bisco Inc); group 3, One-Step Plus (Bisco Inc); and group 4, control. After the application of adhesive systems, composite resin (Aelite, Bisco) was applied over the WMTA. Shear bond strengths were measured using a universal testing machine, and the data were subjected to 1-way analysis of variance and the Scheffé post hoc test.

RESULTS

There was a significant difference between the 4-, 24-, 48-, 72-, and 96-hour measurements in all of the adhesive systems (P < .001). Among all time intervals, group 3 showed significantly higher bond strengths to WMTA than the other groups (P < .001). Groups 1 and 2 were similar (P = .365).

CONCLUSIONS

It was concluded that if a longer waiting time can be practiced after the mixing of WMTA, higher shear bond strength measurements can be obtained. Also, when WMTA was used with total-etch adhesive systems, it showed better shear bond strength.

Hypoxia induces T Helper 17 cell upregulation in cultured peripheral blood mononuclear cells from chronic stage patients of severe cerebral infarction

Studies have shown the IL-17A involvement in human ischemic stroke patients in vivo. Whether the IL-17A expression was originated from Th17 and could be stimulated by hypoxia remained unknown. Here we report the Th17 upregulation in anaerobic cultured PBMC from chronic stage patients of severe cerebral infarction. By using ELISA and FACS we examined IL-1β, IFN-γ, IL-23 and IL-17A protein levels in the supernatants and Th1/Th17 ratios in PBMC. Statistical significance of Th17 but not Th1 upregulation was proved in 6-hr anaerobic cultured patient groups (P < 0.001). Hence, Th17 might be essential in the autoimmune pathogenesis when hypoxia recurs in severe ischemic stroke patients.

Cytotoxicity evaluation of Gutta Flow and Endo Sequence BC sealers

OBJECTIVE

This study evaluated the cytotoxicity of GuttaFlow and EndoSequence BC sealers and compared them with AH Plus and Tubli-Seal sealers.

STUDY DESIGN

Samples (0.5 mg) of freshly mixed or set BC, GuttaFlow, AH Plus, and Tubli-Seal sealers were eluted with 300, 600, and 1,000 μL cell culture medium for 24 and 72 hours. L929 cells were seeded into 96-well plates at 3 × 10(4) cells/well and cultured with 100 μL eluate from each eluate group. Cells cultured only with culture medium served as control. After 24 hours' incubation, the cytotoxicity was evaluated by MTT assay. Cell viability was calculated as the percentage of the control group, and the results were analyzed with a one-way analysis of variance.

RESULTS

For the freshly mixed sealer, cell viability in the AH Plus group was less than in all of the other 3 sealer groups. The Tubli-Seal sealer group had less cell viability than the EndoSequence BC and GuttaFlow sealer groups. For the set sealer, the Tubli-Seal and AH Plus groups had less cell viability than the EndoSequence BC and GuttaFlow sealer groups. There was no cell viability difference between the EndoSequence BC and GuttaFlow sealer groups in the either freshly mixed or set sealer group.

CONCLUSIONS

The GuttaFlow and EndoSequence BC sealers have lower cytotoxicity than the AH Plus and Tubli-Seal sealers.

Use of a matrix for apexification procedure with mineral trioxide aggregate

This articles describes a technique for placement of a matrix barrier prior to use of mineral trioxide aggregate (MTA) as an artificial root-end barrier. The technique also demonstrates the use of a delivery system utilizing large-bore needles for the predictable and precise placement of the barrier materials at the apex of the tooth.

Mineral trioxyde aggregate versus calcium hydroxide in apexification of non vital immature teeth: study protocol for a randomized controlled trial

Background

Pulp necrosis is one of the main complications of dental trauma. When it happens on an immature tooth, pulp necrosis implies a lack of root maturation and apical closure. A therapy called apexification is required to induce the formation of a calcified apical barrier allowing a permanent and hermetic root filling. The aim of this prospective randomized clinical trial is to compare Mineral Trioxide Aggregate(MTA)with Calcium Hydroxide(CH)as materials used to induce root-end closure in necrotic permanent immature incisors.

Methods/Design

This study, promoted by AP-HP, was approved by the ethics committee(CPP Paris Ile de France IV). 34 children aged from 6 to 18 years and presenting a non-vital permanent incisor are selected. Prior to treatment, an appropriate written consent has to be obtained from both parents and from children. Patients are then randomly assigned to either the MTA(experimental)or CH(control)groups. Recalls are performed after 3, 6 and 12 months to determine the presence or absence of a calcified apical barrier through the use of clinical and radiographic exams. Additional criteria such as clinical symptoms, apical radiolucencies, periapical index(PAI)are also noted.

Trial registration

ClinicalTrials.gov no. NCT00472173 (First inclusion: May 10, 2007; Last inclusion: April 23, 2009; study completed: April 15, 2010)

Cytotoxicity of set polymer nanocomposite resin root-end filling materials

AIM

To evaluate the cytotoxicity of two forms of the novel root-end filling materials, polymer nanocomposite (PNC) resins [C-18 Amine montmorillonate (MMT) and VODAC MMT] both containing Chlorhexidine Diacetate Salt Hydrate 2%, and to compare it to that of two widely accepted commercially available materials, ProRoot® MTA and Geristore®.

METHODOLOGY

Elutes of experimental materials extracted after 24 h, 1, 2 and 3 weeks were interacted with the mouse fibroblasts L-929 using a colorimetric cell viability assay (MTS) based on mitochondrial dehydrogenases activity. Using 100% and 50% concentrations of the extracted elutes of the experimental materials the effect of different concentrations of elutes on the cells was analysed. In the positive control group Hygrogold® was added to the cell culture to arrest cells bioactivity. In the negative control group, fresh Dulbecco's Eagle's minimum essential medium supplemented with 10% foetal bovine serum was used to enhance cell bioactivity. Differences in mean bioactivity values were assessed using a t-test and one-way anova (P<0.05).

RESULTS

No significant difference was found in cytotoxicity between ProRoot® MTA, Geristore® and PNC resin C-18 Amine MMT on 24 h, 1, 2 and 3 weeks samples. Sample elutes of PNC resin VODAC MMT, however, revealed cytotoxic activity during most of these experiments.

CONCLUSION

Cytotoxicity of the elutes of PNC resin C-18 Amine MMT was not significantly different from that of ProRoot® and Geristore®. PNC resin VODAC MMT, revealed significantly more cytotoxicity compared to the other tested materials.

Effect of acid-etching procedure on selected physical properties of mineral trioxide aggregate

AIM

To evaluate the effect of acid-etch procedures on the compressive strength and surface microhardness of tooth-coloured mineral trioxide aggregate (MTA).

METHODOLOGY

White ProRoot MTA (Dentsply Tulsa Dental) was mixed and packed into cylindrical tubes of 4 mm in diameter and 6 mm in height. Three groups, each of 15 specimens were subjected to an acid-etch procedure either 4, 24 or 96 h after mixing. The compressive strength was measured and compared with unetched control groups. Differences between groups were analysed using the Kruskall-Wallis test. A further batch of cylindrical specimens of 6 mm in diameter and 12 mm in height were prepared for testing surface microhardness. Three groups of 15 specimens were subjected to the acid-etch procedure at either 4, 24 or 96 h following mixing. Data were subjected to one-way anova. Changes in the surface microstructure before and after the acid-etch procedures were analysed using a scanning electron microscope (SEM).

RESULTS

There was a general trend for the compressive strength and surface microhardness of specimens to increase with time. In terms of compressive strength, the increase was significant between 4 h and the other time periods for both experimental and control groups (P < 0.0001); however, there was no significant difference between 24 and 96 h. The increase in surface microhardness was significant between 4, 24 and 96 h (P < 0.0001). In addition, there was a significant difference between experimental and control groups at all time periods (P < 0.0001). SEM examination revealed morphological differences between the intact and the etched MTA surfaces.

CONCLUSIONS

Acid-etch procedures affected the compressive strength and surface microhardness of ProRoot MTA. This indicates that it may be better to postpone restorative procedures for at least 96 h after mixing MTA. Etching created surface changes that might have the potential to enhance bonding of resinous materials.

Effect of Mineral Trioxide Aggregate Cements on Transforming Growth Factor β1 and Bone Morphogenetic Protein Production by Human Fibroblasts In Vitro

The aim of this study was to evaluate and compare the effects of two commercial mineral trioxide aggregate (MTA) cements (ProRoot MTA and MTA Angelus) on transforming growth factor (TGF)-beta1 and bone morphogenetic protein (BMP)-2 levels produced by cultured human gingival fibroblasts (HGFs). Human gingival tissues were obtained from individuals with healthy periodontium. HGFs were grown at 37 degrees C in humidified atmosphere of 5% CO(2) in Dulbecco's modified Eagle's medium, supplemented with 10% fetal calf serum, penicillin, and streptomycin. After 24 and 72 hours of exposure to the MTA products, HGF viability was determined by using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide assay. TGF-beta1 and BMP-2 levels in cell-free culture media were determined by enzyme-linked immunosorbent assay. Cell viability of the test groups was significantly lower than that of control at 24 and 72 hours (p < 0.05) but showed an increase at 72 hours (p < 0.05). Both test groups showed increased TGF beta-1 levels at 72 hours (p < 0.05), whereas the MTA Angelus group displayed higher TGF beta-1 levels than control and ProRoot MTA groups at 24 and 72 hours (p < 0.05). At 24 hours, BMP-2 levels of the ProRoot group were significantly higher than that of MTA Angelus (p < 0.05). Both test materials increased the BMP-2 levels within time (p < 0.05) and displayed similar levels at 72 hours (p > 0.05). These results suggest that both MTA products are capable of stimulating HGF to produce BMP-2, whereas the stimulatory effect for TGF beta-1 is material dependent.

Genotoxicity in primary human peripheral lymphocytes after exposure to regular and white mineral trioxide aggregate

OBJECTIVE

Taking into consideration that DNA damage plays an important role in carcinogenesis, the purpose of this study was to evaluate whether regular and white mineral trioxide aggregate (MTA) are able to induce genetic damage in primary human cells.

STUDY DESIGN

Human peripheral lymphocytes obtained from 10 healthy volunteers were exposed to 2 presentation forms of MTA at final concentrations ranging from 1 to 1000 microg/mL for 1 hour at 37 degrees C. The negative control group was treated with vehicle control (phosphate buffer solution, PBS) for 1 hour at 37 degrees C and the positive control group was treated with hydrogen peroxide (at 100 microM) for 5 minutes on ice. Results were analyzed by the Friedman nonparametric test.

RESULTS

The results pointed out that either regular or white MTA in all concentrations tested did not induce DNA breakage in human peripheral lymphocytes as depicted by the mean tail moment.

CONCLUSION

In summary, our results indicate that exposure to MTA may not be a factor that increases the level of DNA lesions in human peripheral lymphocytes as detected by single cell gel (comet) assay.