In Vitro Biocompatibility and Oxidative Stress Profiles of Different Hydraulic Calcium Silicate Cements

Introduction

MTA Plus is a new calcium silicate cement with unknown cytotoxicity characteristics. The objectives of this study were to examine the effect of MTA Plus on the viability, apoptosis/necrosis profile, and oxidative stress levels of rat odontoblast-like cells.

Methods

MDPC-23 cells were exposed to gray and white MTA Plus (GMTAP, WMTAP), gray and white ProRoot MTA (GMTA, WMTA) cements, or their eluents. The cells were evaluated for (1) cell viability by using XTT assay, (2) apoptosis/necrosis by using flow cytometry and confocal laser scanning microscopy, and (3) oxidative stress by measuring reactive oxygen species.

Results

XTT assay showed that all test cements exhibited marked initial cytotoxicity that decreased with time. By the end of the third week, GMTAP and GMTA were comparable to untreated cells (negative control) in terms of cell viability, whereas WMTAP and WMTA were significantly lower than the untreated cells. Apoptosis/necrosis profiles of cells exposed to WMTAP and GMTAP were not significantly different from untreated cells, whereas cells exposed to WMTA and GMTA showed significantly less viable cells. All experimental groups exhibited reduction of intracellular reactive oxygen species formation compared with untreated cells, although cells exposed to WMTA were not significantly different from untreated cells.

Conclusions

Both the gray and white versions of MTA Plus possess negligible in vitro cytotoxic risks that are time and dilution dependent. They enrich the spectrum of hydraulic calcium silicate cements currently available to clinicians for endodontic applications.     

Capping a Pulpotomy with Calcium Aluminosilicate Cement: Comparison to Mineral Trioxide Aggregates

Introduction

Calcium aluminate cements have shown little affinity for bacterial growth, low toxicity, and immunogenicity when used as a restoration material, but calcium aluminate cements have not been tested in vivo in pulpotomy procedures.

Methods

To address this question, a calcium aluminosilicate cement (Quick-Set) was tested along with 2 mineral trioxide aggregates, ProRoot MTA and MTA Plus. These cements were used as a capping agent after pulpotomy. Control rats had no pulpotomy, or the pulpotomy was not capped. Proinflammatory cytokines interleukin (IL)-1β and IL-1α were measured, and histology was performed at 30 and 60 days after capping. The nociceptive response was determined by measuring the lengthening of the rat's meal duration.

Results

and Conclusions: IL-1β and IL-1α concentrations were reduced in the capped teeth, but no differences were observed among the 3 cements. Dentinal bridging could be detected at both 30 and 60 days with each of the 3 cements, and the pulps were still vital 60 days after capping. Meal duration significantly shortened after placement of the 3 different cements, indicating a nociceptive response, but there were no differences among the materials. Calcium aluminosilicate cement had similar properties to mineral trioxide aggregates and is a viable option for pulpotomy procedures.     

White Mineral Trioxide Aggregate Induces Migration and Proliferation of Stem Cells from the Apical Papilla

Introduction

Regenerative endodontic protocols recommend white mineral trioxide aggregate (WMTA) as a capping material because of its osteoinductive properties. Stem cells from the apical papilla (SCAP) are presumed to be involved in this regenerative process, but the effects of WMTA on SCAP are largely unknown. Our hypothesis was that WMTA induces proliferation and migration of SCAP.

Methods

Here we used an unsorted population of SCAP (passages 3–5) characterized by high CD24, CD146, and Stro-1 expression. The effect of WMTA on SCAP migration was assessed by using transwells, and its effect on proliferation was determined by the WST-1 assay. Fetal bovine serum (FBS) and calcium chloride–enriched medium were used as positive controls.

Results

The SCAP analyzed here showed a low percentage of STRO-1+ and CD24+ cells. Both set and unset WMTA significantly increased the short-term migration of SCAP after 6 hours (P < .05), whereas calcium chloride–enriched medium did after 24 hours of exposure. Set WMTA significantly increased proliferation on days 1–5, whereas calcium-enriched medium showed a significant increase on day 7, with a significant reduction on proliferation afterwards. SCAP migration and proliferation were significantly and steadily induced by the presence of 2% and 10% FBS.

Conclusions

Collectively, these data demonstrate that WMTA induced an early short-term migration and proliferation of a mixed population of stem cells from apical papilla as compared with a later and longer-term induction by calcium chloride or FBS.     

Solubility and Disintegration of New Calcium Aluminate Cement (EndoBinder) Containing Different Radiopacifying Agents

Introduction

The aim of this study was to evaluate the solubility and disintegration of EndoBinder (EB) containing 3 different radiopacifying agents, bismuth oxide (Bi₂O₃), zinc oxide (ZnO), or zirconium oxide (ZrO₂), in comparison with gray mineral trioxide aggregate (GMTA) and white MTA (WMTA).

Methods

Ten specimens of each cement were made in a stainless steel matrix (20 × 1.5 mm) according to Specification no. 57 of American National Standards Institute/American Dental Association: EB + Bi₂O₃, EB + ZrO, EB + ZnO, WMTA, and GMTA. The specimens were weighed on an accurate analytical scale and immersed in 50 mL distilled and deionized water at 37°C for 7 days. Afterwards, specimens were dried and weighed again to determine mass loss (%). Resulting solutions were analyzed in an atomic absorption spectrophotometer for identification and quantification of chemical elements released.

Results

All cements presented mean values of solubility and disintegration above the American National Standards Institute/American Dental Association Specification no. 57. EB + Bi₂O₃ presented the lowest mass loss (5.08%) and WMTA (6.65%) the highest, with no statistically significant difference (P > .05). The release of several chemical elements was observed, mostly metal ions. Only GMTA and EB + Bi₂O₃ showed the presence of Cr, with significant difference (P < .05). EB + ZnO presented the highest levels of Pb, followed by WMTA (P < .05). For As, the cements presented different release levels, with EB + ZnO showing the highest and GMTA the lowest levels (P < .05). However, the amounts of As and Pb released were lower than the safe limit proposed by ISO 9917-1.

Conclusions

Irrespective of the radiopacifying agents used, EndoBinder presented similar behavior to MTA.     

Effect of Endodontic Cement on Bone Mineral Density Using Serial Dual-energy X-ray Absorptiometry

Introduction

Materials with new compositions were tested in order to develop dental materials with better properties. Calcium silicate–based cements, including white mineral trioxide aggregate (WMTA), may improve osteopromotion because of their composition. Nano-modified cements may help researchers produce ideal root-end filling materials. Serial dual-energy x-ray absorptiometry measurement was used to evaluate the effects of particle size and the addition of tricalcium aluminate (C₃A) to a type of mineral trioxide aggregate–based cement on bone mineral density and the surrounding tissues in the mandible of rabbits.

Methods

Forty mature male rabbits (N = 40) were anesthetized, and a bone defect measuring 7 × 1 × 1 mm was created on the semimandible. The rabbits were divided into 2 groups, which were subdivided into 5 subgroups with 4 animals each based on the defect filled by the following: Nano-WMTA (patent application #13/211.880), WMTA (as standard), WMTA without C₃A, Nano-WMTA + 2% Nano-C₃A (Fujindonjnan Industrial Co, Ltd, Fujindonjnan Xiamen, China), and a control group. Twenty and forty days postoperatively, the animals were sacrificed, and the semimandibles were removed for DXA measurement.

Results

The Kruskal-Wallis test followed by the Mann-Whitney U test showed significant differences between the groups at a significance level of P < .05. P values calculated by the Kruskal-Wallis test were .002 for bone mineral density at both intervals and P_20 day = .004 and P_{40 day} = .005 for bone mineral content.

Conclusions

This study showed that bone regeneration was enhanced by reducing the particle size (nano-modified) and C₃A mixture. This may relate to the existence of an external supply of minerals and a larger surface area of nano-modified material, which may lead to faster release rate of Ca²⁺, inducing bone formation. Adding Nano-C₃A to Nano-WMTA may improve bone regeneration properties.     

Histology of NeoMTA Plus and Quick-Set2 in Contact with Pulp and Periradicular Tissues in a Canine Model

Introduction

NeoMTA Plus (Avalon Biomed Inc, Bradenton, FL) is a tricalcium silicate material similar to the first mineral trioxide aggregate product, ProRoot MTA (Dentsply Sirona, York, PA), but with improvements such as decreased setting time, increased ion release, increased water sorption, and nonstaining radiopacifiers. Quick-Set2 (Avalon Biomed Inc) is a newly formulated calcium aluminosilicate material that has a faster setting time and increased acid resistance and is nonstaining. The purpose of this study was to compare the healing of pulpal and periapical tissues in dogs after exposure to NeoMTA Plus and Quick-Set2 after pulpotomy and root-end surgery procedures.

Evaluation of Compressive Strength of Hydraulic Silicate-based Root-end Filling Materials

Introduction

Hydraulic silicate cements such as mineral trioxide aggregate (MTA) have many clinical advantages. Newer hydraulic silicate materials have been developed that improve on the limitations of mineral trioxide aggregate such as the long setting time and difficult handling characteristics. The purpose of this study was to examine the effect of saline and fetal bovine serum (FBS) on the setting and compressive strength of the following hydraulic silicate cements: ProRoot MTA (white WMTA; Dentsply International, Tulsa Dental Specialties, Johnson City, TN), EndoSequence Root Repair Material (Brasseler USA, Savannah, GA), MTA Plus (MTAP; Avalon Biomed Inc, Bradenton, FL), and QuickSet (QS; Avalon Biomed Inc, Bradenton, FL).

Methods

Samples of root-end filling materials were compacted into polyethylene molds. Samples were exposed to FBS or saline for 7 days. A universal testing machine was used to determine the compressive strengths.

Results

QS had significantly lower compressive strength than all other materials (P < .001). White MTA and MTAP mixed with liquid had lower compressive strengths after exposure to FBS compared with saline (P = .003). ERRM, MTAP mixed with gel, and QS were not affected by the exposure to FBS.

Conclusions

New silicate-based root-end filling materials, other than QS, have compressive strength similar to MTA. Within the limits of this study, premixed materials and those mixed with antiwashout gel maintain their compressive strength when exposed to biological fluids.     

Influence of Acidic Environment on Properties of Biodentine and White Mineral Trioxide Aggregate: A Comparative Study

Introduction

The purpose of this study was to evaluate the surface microhardness, compressive strength, bond strength, and morphologic microstructures of Biodentine (BD; Septodont, Saint Maur des Fossés, France) and white mineral trioxide aggregate (WMTA) after exposure to a range of acidic pH levels.

Methods

For each test, 4 groups of each material were exposed to pH values of 7.4, 6.4, 5.4, and 4.4, respectively, for 7 days. The surface hardness was determined using Vickers microhardness. The compressive strength and micro–push-out bond strength were determined using the universal testing machine at a crosshead speed of 0.5 mm/min. The morphologic microstructures of specimens were evaluated using scanning electron microscopy.

Results

BD showed higher surface hardness, compressive strength, and bond strength to root dentin compared with WMTA after exposure to different pH values. A substantial change in the microstructure of BD and WMTA occurred after exposure to different pH values. WMTA appeared to be more sensitive to acidic pH environments than BD.

Conclusions

BD material seems more appropriate for use when exposed to an acidic environment compared with WMTA.     

The effect of epigallocatechin-3-gallate (EGCG) on human alveolar bone cells both in vitro and in vivo

Objective

The effects of epigallocatechin-3-gallate (EGCG), a major catechin in green tea, on human and mouse osteoblasts remain controversial. This study investigated the direct effects of EGCG on human alveolar bone-derived cells (hABCs) both in vitro and in vivo.

Design

hABCs which were collected from eight children (aged 7–9 years, seven males and one female) were treated with EGCG at various concentrations (1, 5, 10, 25, and 50 μM), and a proliferation assay, flow cytometric analysis for apoptosis evaluation, migration assay, and in vitro osteogenic differentiation were performed. hABCs that were pretreated with 10 μM EGCG and mixed with calcium phosphate carrier combined with EGCG (0.1, 0.5, or 1.5 mg) in vivo were transplanted into immunodeficient mouse. Histological staining, quantitative gene expressions, and alkaline phosphatase activity were evaluated in the retrieved transplants.

Results

The proliferation and migration were decreased when EGCG was present at over 25 μM. The osteogenic differentiation increased slightly when EGCG was present at up to 10 μM, and clearly decreased for higher concentrations of EGCG. In vivo, the potential for hard-tissue formation was slightly higher for the group with 0.1 mg of EGCG than for the control group, and decreased sharply for higher concentrations of EGCG.

Conclusion

The present observations suggest that EGCG at a low concentration can slightly enhance the osteogenic effect in vivo, whereas at a higher concentration it can prevent the osteogenic differentiation of hABCs both in vitro and in vivo.     

EphB–EphrinB Interaction Controls Odontogenic/Osteogenic Differentiation with Calcium Hydroxide

Introduction

Calcium hydroxide is used in direct pulp capping of uncontaminated exposed vital pulps caused by mechanical or traumatic injury. Calcium hydroxide creates a high alkaline pH environment and initiates a mineralized tissue formation in the pulp. The exact mechanism by which calcium hydroxide induces the reparative dentin formation is unknown. Because Eph receptors and ephrin ligands play a role in pulp stem cell migration and proliferation, our hypothesis is that calcium hydroxide–related odontogenic/osteogenic differentiation may be associated with Eph-ephrin interaction. The aim of this study was to investigate whether Eph-ephrin interaction regulates odontogenic/osteogenic differentiation with calcium hydroxide.

Methods

Primary pulp cells were harvested from the molars of C57BL/6 mice. The cells were treated with calcium hydroxide. Immunofluorescence was used to detect protein expression. A knockout of the ephrinB1 or EphB2 gene was performed with short hairpin RNAs. Cell migration, proliferation, and gene expression were then analyzed.

Results

Calcium hydroxide stimulated EphB2 gene expression but suppressed ephrinB1 gene expression at the proliferation stage. However, calcium hydroxide stimulated both ephrinB1 and EphB2 gene expression at the differentiation stage. In addition, EphB2 localized at ephrinB1–positive cells at the area of Dentin sialoprotein (DSP) staining, which increased with calcium hydroxide treatment. Knockdown of ephrinB1–EphB2 significantly suppressed cell proliferation. Additionally, knockdown of the ephrinB1 gene caused cell migration, whereas a lack of the EphB2 gene suppressed calcium hydroxide–induced mineralization from primary pulp cells.

Conclusions

EphrinB1–EphB2 interaction contributes to calcium hydroxide–induced odontogenic/osteogenic differentiation. This observation is the first finding of the mechanism of calcium hydroxide–induced odontogenic/osteogenic differentiation.     

Glass ionomer cements: Effect of strontium substitution on esthetics,radiopacity and fluoride release

Objective

SrO and SrF₂ are widely used to replace CaO and CaF₂ in ionomer glasses to produce radiopaque glass ionomer cements (GIC). The purpose of this study was to evaluate the effects of this substitution on release of ions from GIC as well as its effect on esthetics (translucency) and radiopacity.

Materials and methods

Cements were produced from ionomer glasses with varying content of Sr, Ca and F. The cements were stored in dilute acetic acid (pH 4.0) for up to 7 days at 37 °C. Thereafter, the cements were removed and the solution was tested for F⁻, Sr²⁺, Ca²⁺, and Al³⁺ release. Radiopacity and translucency were measured according to BS EN ISO 9917-1:2003.

Results

Ion release was linear to t^1/2 suggesting that this is a diffusion controlled mechanism rather than dissolution. The fluoride release from the cements is enhanced where some or all calcium is replaced by strontium. Radiopacity shows a strong linear correlation with Sr content. All cements were more opaque than the C_0.70 0.55 standard but less opaque than the C_0.70 0.90 standard which is the limit for the ISO requirement for acceptance.

Significance

This study shows that the replacement of calcium by strontium in a glass ionomer glass produces the expected increase in radiopacity of the cement without adverse effects on visual properties of the cement. The fluoride release from the cements is enhanced where some or all calcium is replaced by strontium.     

Comparison of intracanal EndoSequence Root Repair Material and ProRoot MTA to induce pH changes in simulated root resorption defects over 4 weeks in matched pairs of human teeth

Introduction

Intracanal mineral trioxide aggregate (MTA) may provide an alternative to calcium hydroxide in the treatment of external inflammatory root resorption. This in vitro study using human matched pairs of teeth compared white ProRoot MTA (WMTA; (Dentsply Tulsa Dental Specialties, Tulsa, OK) and an alternative material with purportedly improved handling properties, EndoSequence Root Repair Material (ES; Brasseler USA, Savannah, GA), by measuring pH in simulated root surface resorptive defects after intracanal placement. The null hypothesis tested was that there is no difference between WMTA and ES.

Methods

Bilaterally matched pairs (n = 24) of extracted, human, single-rooted teeth were instrumented to apical size 50/.06, and root surface cavities were prepared at 5 mm and 2 mm from the apex. Root canals of experimental matched pairs (n = 20) were filled with WMTA or ES; control pairs (n = 4) were filled with calcium hydroxide (positive control [POS]) or saline (negative control [NEG]). Teeth were sealed coronally and apically and immersed in saline. The pH in root surface cavities was measured at 20 minutes, 3 hours, 24 hours, 1 week, 2 weeks, 3 weeks, and 4 weeks.

Results

The pH at 5 mm when compared with the 2-mm level was significantly higher for the WMTA, ES, and POS groups (P < .05, paired t tests); therefore, each level was analyzed separately. At both the 2-mm and 5-mm levels, significant pH changes occurred over time in the WMTA, ES (both P < .0001, repeated-measures analysis of variance), and POS (P < .0001, Friedman test) groups and not in the NEG group (mean pH = 7.32 ± 0.04, P > .05). There were no differences between WMTA and ES at 20 minutes and 3 hours at both levels or at 24 hours at 5mm. The pH of WMTA was higher than ES by 24 hours at the 2-mm level (8.79 vs 8.56, P < .05, paired t test) and after 1 week at the 5-mm level (8.91 vs 8.05, P < .0001) and was thereafter always significantly higher in WMTA compared with ES (P < .0001). The null hypothesis was rejected.

Conclusions

In matched pairs of teeth, intracanal placement of WMTA compared with ES resulted in a higher pH in simulated root resorption defects that was time and root level dependent.     

A review of the bioactivity of hydraulic calcium silicate cements

Objectives

In tissue regeneration research, the term “bioactivity” was initially used to describe the resistance to removal of a biomaterial from host tissues after intraosseous implantation. Hydraulic calcium silicate cements (HCSCs) are putatively accepted as bioactive materials, as exemplified by the increasing number of publications reporting that these cements produce an apatite-rich surface layer after they contact simulated body fluids.

Methods

In this review, the same definitions employed for establishing in vitro and in vivo bioactivity in glass–ceramics, and the proposed mechanisms involved in these phenomena are used as blueprints for investigating whether HCSCs are bioactive.

Results

The literature abounds with evidence that HCSCs exhibit in vitro bioactivity; however, there is a general lack of stringent methodologies for characterizing the calcium phosphate phases precipitated on HCSCs. Although in vivo bioactivity has been demonstrated for some HCSCs, a fibrous connective tissue layer is frequently identified along the bone–cement interface that is reminiscent of the responses observed in bioinert materials, without accompanying clarifications to account for such observations.

Conclusions

As bone-bonding is not predictably achieved, there is insufficient scientific evidence to substantiate that HCSCs are indeed bioactive. Objective appraisal criteria should be developed for more accurately defining the bioactivity profiles of HCSCs designed for clinical use.     

Calcium phosphate bone cement with 10 wt% platelet-rich plasma in vitro and in vivo

Objectives

The aim of this study was to evaluate the performance of a 10 wt% platelet-rich plasma (PRP) additive composite with calcium phosphate cement (CPC) in vitro and in vivo.

Methods

The in vitro testing of modulus, the apatite conversion rate, morphology, cell and alkaline phosphatase (ALP) activities, and in vivo testing of histological examinations between two groups of 10 wt% PRP/CPC and CPC were characterised and compared.

Results

Although the crystallite morphologies showed a retarded effect in the PRP/CPC group in vitro, the modulus results showed that the 10 wt% PRP/CPC group had a significant reduction in strength but had no significant changes in the relative conversion ratio of the apatite phase with CPC only. The osteogenic evaluation of ALP expression was significantly increased by the PRP additives group with stem cells (D1) cultured for different periods (2–32 days). Our histological examinations showed that greater remodelling and the phenomenon of isolated/detached CPC particles were significantly observed at 9 weeks after implantation when the 10 wt% PRP/CPC composite was used.

Conclusion

The results demonstrate that CPC may be a potential candidate as a carrier with PRP additives for bone regeneration.     

Effects of a novel hydration accelerant on the biological and mechanical properties of white mineral trioxide aggregate

Introduction

The objective of this study was to investigate the antibacterial, biocompatibility, and mechanical properties of mineral trioxide aggregate (MTA) set using a calcium lactate gluconate (CLG) solution.

Methods

ProRoot white MTA (WMTA) (Dentsply Tulsa Dental, Tulsa, OK) was used as the control group; MTA-like cement was prepared by mixing Portland cement/bismuth oxide/calcium sulfate (75/20/5) as the experiment group. A solution of 23.1 wt% CLG was used as a hydration accelerant and was compared with deionized water (DDW). Changes in pH values, antibacterial properties, in vitro cell viability, and diametral tensile strength (DTS) of the hydrated cements were assessed.

Results

Like WMTA, pH values for the MTA-like cement set using DDW and the CLG solution showed minor but statistically significant differences (P < .05). The antibacterial effects of hydrated specimens set by DDW and CLG against Streptococcus mutans assessed with an in vitro tube dilution test showed a significant difference in the early hydration time but no significant difference after 60 minutes (P > .05). A mouse osteoblastic cell (MC3T3-E1)-based MTT assay revealed that WMTA set using CLG had significantly higher cell viability than that set using DDW (P < .05). The DTS test for hydrated MTA-like cement with different liquids showed a significant difference on day 1 but no statistical difference on day 21.

Conclusions

The results suggest that using a CLG solution as the hydration accelerant may enhance the biocompatibility but not compromise WMTA’s antibacterial and mechanical properties.     

Transdentinal cytotoxicity of resin-based luting cements to pulp cells

Objectives

The aim of this study was to evaluate the transdentinal cytotoxicity of components released from different resin-based luting cements to cultured MDPC-23 odontoblast-like cells and human dental pulp cells (HDPCs).

Materials and methods

Artificial pulp chamber (APC)/dentin disc sets were distributed into four groups according to the materials tested (n = 10), as follows: G1, control (no treatment); G2, resin-modified glass-ionomer cement (RelyX Luting 2); G3, self-adhesive resin cement (RelyX U200); and G4, conventional resin cement (RelyX ARC). The materials were applied to the occlusal surfaces (facing up) of the dentin discs adapted to the APCs. The pulpal surfaces of the discs were maintained in contact with culture medium. Then, an aliquot of 400 μL from the extract (culture medium + resin-based components that diffused through dentin) of each luting cement was applied for 24 h to HDPCs or MDPC-23 cells previously seeded in wells of 24-well plates. Cell viability analysis was performed by the MTT assay (1-way ANOVA/Tukey test; α = 5 %).

Results

For MDPC-23 cells, RelyX ARC (G4) and RelyX Luting 2 (G2) caused greater reduction in cell viability compared with the negative control group (P < 0.05). Only the HDPCs exposed to RelyX ARC (G4) extract showed a tendency toward viability decrease (9.3 %); however, the values were statistically similar to those of the control group (G1) (P > 0.05).

Conclusions

In accordance with the safe limits of ISO 10993-5:1999 (E) recommendations, all resin-based luting cements evaluated in this study can be considered as non-toxic to pulp cells.

Clinical relevance

Cytotoxicity of resin-based luting cements is material-dependent, and the different protocols for the application of these dental materials to dentin may interfere with their cytotoxicity.

     

In vitro wear gap formation of self-adhesive resin cements: A CLSM evaluation

Objectives

To evaluate the depth of wear gaps of new self-adhesive cements after toothbrush abrasion and ACTA wear test.

Methods

Luting spaces (325 ± 25 μm width, 2 mm depth) were produced in Empress 2 ceramic blocks with a diamond saw to obtain flat substrate segments for toothbrush abrasion (n = 24) and ACTA wear (n = 27). After etching and silanization, the slits were filled with 8 self-adhesive cements, 2 conventional resin cements and 1 flowable composite, stored for 2 weeks in distilled water at 37 °C and planished to the cement level. Toothbrush abrasion was carried out in a toothbrush simulator (Willytec, Germany) for 20,000 cycles (load 1 N) using an abrasive slurry based on a commercial toothpaste (Elmex, Gaba, Germany, RDA = 77). The ACTA wear experiment was performed following the ACTA protocol in millet seed slurry for 400,000 cycles (Willytec). The gap replicas were measured for vertical wear loss under a confocal laser scanning microscope (CLSM). The data were analyzed using one-way ANOVA and a mod-LSD test at p < 0.05.

Results

Toothbrush wear values were lower than the ones obtained for the ACTA wear test for all cements. In the toothbrush test Bifix SE, Clearfil SA, SmartCem 2, G-Cem and Maxcem Elite obtained the highest values together with Grandio Flow. Grandio Flow and AllCem showed to be the most resistant to the ACTA wear test, while SpeedCem the least resistant. No correlation was found between the two wear test experiments.

Conclusion

Self-adhesive cements have good wear resistance to toothbrush abrasion but most of them wear more rapidly under higher loads in the ACTA test than conventional resin cements and flowable composites.