Effect of acidic pH on microhardness and microstructure of theraCal LC, endosequence, mineral trioxide aggregate, and biodentine when used as root repair material

Effect of different root canal irrigants on surface roughness and microhardness of Biodentine combined with triple antibiotic paste: An in vitro study

Background

Biodentine is widely used for endodontic applications; recently, it has been incorporated with triple antibiotic paste (TAP). The effect of endodontic irrigants on the physical characteristics of this new combination needs to be studied.

Aims

The aim of the study was to evaluate the surface roughness and microhardness of Biodentine incorporated with TAP subjected to various endodontic irrigants.

Materials and Methods

Hundred cylindrical discs (6 mm × 3 mm) were prepared by mixing the Biodentine with TAP (3:1). The specimens were subjected to different irrigating solutions for 5 min in 5 groups (n = 20): Group 1: distilled water (control), Group 2: 2.5% sodium hypochlorite, Group 3: 17% ethylenediaminetetraacetic acid, Group 4: 2% chlorhexidine (CHX), and Group 5: 2% chitosan nanoparticles (CSNs). Half of the specimens in each group were subjected to surface roughness (n = 10) and another half to microhardness (n = 10). Surface roughness was measured using a surface roughness tester, and digital Vickers microhardness testing was performed on each specimen.

Statistical Analysis

One-way ANOVA and post hoc Tukey's tests (P ≤ 0.05) were used.

Results

The highest microhardness was found with 2% CSN, whereas 2% CSN and 2% CHX had a minimal effect on the surface roughness of Biodentine incorporated with TAP (P ≤ 0.05).

Conclusion

The root canal irrigant 2% CSN exhibited the highest microhardness and least surface roughness of modified Biodentine with TAP.

Approaches to vital pulp therapies

Tooth decay, which leads to pulpal inflammation due to the pulp's response to bacterial components and byproducts is the most common infectious disease. The main goals of clinical management are to eliminate sources of infection, to facilitate healing by regulating inflammation indental tissue, and to replace lost tissues. A variety of novel approaches from tissue engineering based on stem cells, bioactive molecules, and extracellular matrix-like scaffold structures to therapeutic applications, or a combination of all these are present in the literature. Shortcomings of existing conventional materials for pulp capping and the novel approches aiming to preserve pulp vitality highligted the need for developing new targeted dental materials. This review looks at the novel approches for vital pulp treatments after briefly addresing the conventional vital pulp treatment as well as the regenerative and self defense capabilities of the pulp. A narrative review focusing on the current and future approaches for pulp preservation was performed after surveying the relevant papers on vital pulp therapies including pulp capping, pulpotomy, and potential approaches for facilitating dentin-pulp complex regeneration in PubMed, Medline, and Scopus databases.

Comparison of Marginal Adaptation, Surface Hardness and Bond Strength of Resected and Retrofilled Calcium Silicate-based Cements Used in Endodontic Surgery: An In Vitro Study

AIMS

This study compared the effects of orthograde and retrograde methods on marginal adaptation, surface hardness, and push-out bond strength (POBS) of three calcium silicate-based used in endodontic surgery.

MATERIALS AND METHODS

Ninety single-rooted human mandibular premolars were randomly assigned into six groups (n = 15/group): groups I and II, ProRoot mineral trioxide aggregate (MTA) with orthograde and retrograde methods; groups III and IV, Biodentine (BD) with orthograde and retrograde methods; groups V and VI, iRoot BP Plus (BP-RPM) with orthograde and retrograde methods. After obturation, the apical 3 mm of each root was sectioned into two 1-mm-thick root slices and evaluated for marginal adaptation using a scanning electron microscope, surface hardness using Vickers hardness tester and POBS using a universal testing machine.

RESULTS

Orthograde placement had a higher maximum gap width than retrograde placement (p < 0.05), but there was no significant difference among the tested materials (p > 0.05). Biodentine exhibited lower surface hardness than ProRoot MTA and iRoot BP Plus (p < 0.05), but there was no significant difference between ProRoot MTA and iRoot BP Plus (p > 0.05). Orthograde placement had higher POBS compared with retrograde placement (p < 0.05). Biodentine had higher POBS than iRoot BP Plus (p < 0.05), but no significant difference from ProRoot MTA (p > 0.05). The failure mode was mainly mixed for all the tested materials regardless of material type or placement technique.

CONCLUSION

The retrograde method had better marginal adaptation; however, the orthograde method provided better dislodgement resistance. Biodentine had lower surface hardness than MTA and iRoot BP Plus with both techniques, whereas iRoot BP Plus demonstrated lower dislodging resistance than BD.

CLINICAL SIGNIFICANCE

The current findings suggest that orthograde technique, a simpler periapical surgery, with ProRoot MTA provides potentially better surface hardness and POBS than BD and iRoot BP Plus in single-canal teeth.

The effect of acidity on the physicochemical properties of two hydraulic calcium silicate-based cements and two calcium phosphate silicate-based cements

BACKGROUND

Bioceramic cements have been widely used in endodontic treatment. This study aimed to compare the microhardness, elastic modulus, internal microstructure and chemical compositions of Biodentine, WMTA, ERRM Putty, iRoot FS and IRM after exposure to PBS, butyric acid, and butyric acid followed by PBS.

METHODS

Specimens of each material were prepared and randomly divided into 5 subgroups (n = 5): subgroup A: PBS (pH = 7.4) for 4 days, subgroup B: PBS (pH = 7.4) for 14 days, subgroup C: butyric acid (pH = 5.4) for 4 days, subgroup D: butyric acid (pH = 5.4) for 14 days, subgroup E: butyric acid for 4 days followed by 10 days in contact with PBS. The surface microhardness, elastic modulus, internal morphologic and chemical compositions of specimens were analyzed.

RESULTS

The microhardness and elastic modulus values of all materials were significantly higher in the presence of PBS compared to exposure to butyric acid, with the same setting time (P < 0.01). After 4-day exposure to butyric acid followed by 10-day exposure to PBS, the microhardness values returned to the same level as 4-day exposure to PBS (P > 0.05). Biodentine showed significantly higher microhardness and elastic modulus values than other materials, while IRM displayed the lowest (P < 0.01).

CONCLUSION

Biodentine seems the most suitable bioceramic cements when applied to an infected area with acidic pH. Further storage at neutral pH, e.g. PBS reverses the adverse effects on bioceramic cements caused by a low pH environment.

Effect of different irrigants on the push-out bond strength of biodentine and TheraCal LC when used for perforation repair in simulated condition

Background

Perforation repair materials should have excellent sealing ability and dislodgement resistance. While several materials have been employed for perforation repair, newer calcium-silicate materials, such as Biodentine and TheraCal LC, have shown promising outcomes.

Aims

This study aimed to evaluate the effect of different irrigants on the dislodgement resistance of Biodentine and TheraCal LC when used for perforation repair in simulated conditions.

Methods and Material

3% sodium hypochlorite, 2% chlorhexidine gluconate, and 17% EDTA were evaluated for their effect on the dislodgement resistance of Biodentine and TheraCal LC. 48 permanent mandibular molars were selected for the study. The samples were divided into two groups: Group I - Biodentine and Group II - TheraCal LC, with 24 samples each.

Statistical Analysis

The mean dislodgement resistance and standard deviation of Group I (Biodentine) and Group II (TheraCal LC) were compared and Failure pattern analysis was done.

Results

Biodentine showed a significant decrease in push-out bond strength after contact with 3% NaOCl, 2% CHX, and 17% EDTA whereas, TheraCal LC showed no significant decrease in push-out bond strength after exposure to 3% NaOCl, 2% CHX, and 17% EDTA.

Conclusions

Overall, TheraCal LC can be considered good perforation repair material with excellent physical and biological properties.

To compare the efficacy of various organic solvents on retrievability of Biodentine and their effect on microhardness of Biodentine and radicular dentin: An in vitro study

Background

Rotary and ultrasonic instruments are not appreciable in the complete removal of Biodentine from root canals. Therefore, organic solvents can be used as an adjunct for its retrieval.

Aim

The aim of this study was to compare the efficacy of 10% citric acid, 2% acetic acid, and 20% tartaric acid on the microhardness of Biodentine and radicular dentin.

Materials and Methods

Forty single-rooted extracted teeth were decoronated at the cementoenamel junction and root canals were prepared with peeso reamers. Two-millimeter sections were obtained and restored with Biodentine. All samples were subjected to Vicker's microhardness test to record the microhardness of Biodentine and radicular dentin. Samples were randomly divided into four experimental groups and treated with (n = 20) - distilled water, 10% citric acid, 2% acetic acid, and 20% tartaric acid groups for 10 min, after which specimens were again subjected to the same microhardness test.

Statistical Analysis

The data were subjected to Kruskal-Wallis ANOVA test, followed by Wilcoxon signed-rank test with a level of significance set at P ≤ 0.05.

Results

10% citric acid followed by 2% acetic acid exhibited the lowest mean microhardness values after immersing in respective solutions, whereas 20% tartaric acid exhibited the highest mean microhardness values on Biodentine and radicular dentin.

Conclusion

10% citric acid can be used for retrieving Biodentine from root canals for a limited time without adversely affecting the physical and chemical composition of radicular dentin.

Effect of Different Adhesive Strategies on the Microshear Bond Strength of Calcium-Silicate-Based Materials

Aim:

To evaluate the microshear bond strength (µSBS) of mineral trioxide aggregate and Biodentine to various resin-based materials using different adhesive strategies.

Materials and Methods:

Three resin-based materials—a self-adhering resin composite with or without acid etching (Vertise flow; Kerr, Orange, CA, USA), a conventional flowable composite with a total-etch adhesive (Filtek Ultimate Flowable; 3M ESPE, St. Paul, MN, USA), and a flowable resin-modified glass ionomer cement (RMGIC) without any surface modification (Ionoseal; VOCO GmbH, Cuxhaven, Germany)—and two calcium-silicate-based materials—Biodentine and BIOfactor mineral trioxide aggregate (MTA)—were tested. A total of 100 cylindrical acrylic molds were prepared. Biodentine and BIOfactor MTA were prepared and placed into the central holes on the molds. Specimens were divided into two main groups according to materials and into five subgroups ( n = 10). µSBS were evaluated using a µSBS testing device. The failure modes were examined under a stereomicroscope with magnification. They were categorized as adhesive, cohesive, or mixed. Data were analyzed using two-way analysis of variance (ANOVA) and Tukey test. The significance level was taken as α = 0.05.

Results:

It was observed that both calcium-silicate-based material type and resin-based material type influenced the µSBS significantly according to two-way ANOVA. Biodentine exhibited higher bond strength values than MTA. However, no statistically significant interaction was demonstrated between these factors ( P = .396). The µSBS values of intermediate materials to Biodentine and MTA were listed from the lowest to the highest as follows: RMGIC < Acid Etch + RMGIC < SARC (self-adhering resin composite) < FC (flowable composite) < Acid Etch + SARC.

Conclusion:

Self-adhering composites can be used on calcium-silicate-based materials in vital pulp treatments because of their mechanical properties. Acid-etching ensures high µSBS values. Although the µSBS of Biodentine were higher than MTA according to this study’s results, there was no statistically significant difference in µSBS of FC and acid-etched SARC to MTA.

Compressive strength, surface roughness, and surface microhardness of principle tricalcium silicate-based endodontic cements after universal adhesive application

Aims and Background

It was aimed to evaluate compressive strength (CS), surface roughness, and microhardness of mineral trioxide aggregate (ProRoot MTA) and Biodentine (BD) after adhesive application.

Materials and Methods

Tests was carried out according to international ISO standard. ProRoot MTA and BD were prepared in Teflon molds according to manufacturer's instructions: n = 210 for CS; n = 210 for microhardness. Samples were incubated for 7 days at 37°C in 100% humidity. Surfaces were smoothed with up to 2000 grits of silicon-carbide sandpaper on abrasive device at 150 rpm, randomly divided into seven groups (n = 15). Clearfil Universal Bond, All Bond Universal, and Single Bond Universal (SBU) were applied in both total-etch and self-etch (SE) modes. Adhesives were applied according to manufacturers' recommendations (no adhesive used in control). CS was performed at speed of 1 mm/min, microhardness at 100 gr for 15 s. The surface roughness of the samples was analyzed with atomic force microscopy. Two-way analysis of variance and post hoc Tukey tests were used for the evaluation of the data.

Results

Man CS and microhardness values between ProRoot MTA and BD were as follows: 24.9 N, 72.6 HV; 59.8 N, 59.0 HV, respectively. In CS, BD was higher than ProRoot MTA (P < 0.05). In other comparisons except for SBU SE group (P < 0.05), BD and ProRoot MTA showed similar results (P > 0.05). However, ProRoot MTA was found higher than BD regarding microhardness (P < 0.05). As a result of the adhesive application in both BD and ProRoot MTA groups, a decrease in surface roughness was observed compared to the control group.

Conclusion

BD exhibited better results than ProRoot MTA regarding CS. However, ProRoot MTA was found to be more successful than BD in terms of microhardness. BD and ProRoot MTA showed similar physical properties in terms of surface roughness. To improve regenerative procedures, besides the selection of bioceramic cements, the interaction between cements and materials applied during coronal restoration should be considered.

Effect of a resin-modified calcium silicate cement on inflammatory cell infiltration and reparative dentin formation after pulpotomy in rat molars

Resin monomers and polymerisation initiators have been shown to be cytotoxic for pulp cells and to disturb odontoblast differentiation. This study aimed to compare the effect of a resin-modified calcium silicate cement (TheraCal LC; TC) and a resin-free calcium silicate cement (ProRoot MTA; PR) on pulpal healing after pulpotomy. Pulpotomy was performed on the maxillary first molars of 8-week-old rats using either PR or TC. After 1, 3, 7, 14 and 28 days, pulpal responses were assessed by micro-computed tomography, haematoxylin-eosin staining and immunostaining against CD68, which is a pan-macrophage marker. The results showed that pulpotomy with TC induced persistent infiltration of inflammatory cells, including CD68-positive macrophages, and delayed the formation of reparative dentin as compared with that with PR, although both materials allowed pulpal healing over the long term. Therefore, resin-modified TC was not as biocompatible nor bioinductive as resin-free PR when applied on the healthy pulp of rat molars.

Comparison of Four Dental Pulp-Capping Agents by Cone-Beam Computed Tomography and Histological Techniques—A Split-Mouth Design Ex Vivo Study

Dental pulp-capping is done to preserve vital teeth when the pulp is exposed due to caries, trauma or instrumentation. Various materials are used as pulp-capping agents. The introduction of newer materials requires scientific studies to assess their clinical efficacy. The study was designed as a split-mouth randomized analysis of four pulp-capping agents (calcium hydroxide, mineral trioxide aggregate (MTA), Biodentine and EndoSequence root repair material (ERRM)). Based on selection criteria, 15 orthodontic patients requiring the extraction of four premolars (60 teeth total) were included in the study. After pulp-capping, the teeth were extracted after 8 weeks. We analyzed the extracted teeth using cone-beam computed tomography (CBCT) and histological sections to determine the quality of the dentinal bridge and the pulpal response. Ordinal scores were given based on the completeness of the dentinal bridge, the type of bridge and the degree of pulpal inflammation. Results were analyzed using a Kruskal–Wallis test (p < 0.05) with post hoc Conover values being used when applicable. All four pulp-capping materials elicited dentinal bridge formation (60/60). MTA had the highest scores (10/15) in dentinal bridge formation followed by ERRM (8/15). Both materials showed more samples with complete dentinal bridges (9/15 each) and a favorable pulpal response (15/15). Teeth capped with calcium hydroxide showed more cases of incomplete bridge formation (9/15) and pulpal inflammation. These differences in dentinal bridge formation and pulpal inflammation were statistically significant (p 0.001 and p 0.00005, respectively), with post hoc tests revealing no significant differences between MTA and ERRM (p 0.49 and p 0.71, respectively). MTA and ERRM performed better than the other pulp-capping materials but did not differ significantly from each other. The individual preference for a pulp-capping material may be based on clinical efficacy and handling characteristics.

Calcium Silicate-Based Biocompatible Light-Curable Dental Material for Dental Pulpal Complex

Dental caries causes tooth defects and clinical treatment is essential. To prevent further damage and protect healthy teeth, appropriate dental material is a need. However, the biocompatibility of dental material is needed to secure the oral environment. For this purpose, biocompatible materials were investigated for incorporated with dental capping material. Among them, nanomaterials are applied to dental materials to enhance their chemical, mechanical, and biological properties. This research aimed to study the physicochemical and mechanical properties and biocompatibility of a recently introduced light-curable mineral trioxide aggregate (MTA)-like material without bisphenol A-glycidyl methacrylate (Bis-GMA). To overcome the compromised mechanical properties in the absence of Bis-GMA, silica nanoparticles were synthesized and blended with a dental polymer for the formation of a nano-network. This material was compared with a conventional light-curable MTA-like material that contains Bis-GMA. Investigation of the physiochemical properties followed ISO 4049. Hydroxyl and calcium ion release from the materials was measured over 21 days. The Vickers hardness test and three-point flexural strength test were used to assess the mechanical properties. Specimens were immersed in solutions that mimicked human body plasma for seven days, and surface characteristics were analyzed. Biological properties were assessed by cytotoxicity and biomineralization tests. There was no significant difference between the tested materials with respect to overall physicochemical properties and released calcium ions. The newly produced material released more calcium ions on the third day, but 14 days later, the other material containing Bis-GMA released higher levels of calcium ions. The microhardness was reduced in a low pH environment, and differences between the specimens were observed. The flexural strength of the newly developed material was significantly higher, and different surface morphologies were detected. The recently produced extract showed higher cell viability at an extract concentration of 100%, while mineralization was clear at the conventional concentration of 25%. No significant changes in the physical properties between Bis-GMA incorporate material and nanoparticle incorporate materials.

Premixed bioceramics versus mineral trioxide aggregate in furcal perforation repair of primary molars: in vitro and in vivo study

OBJECTIVES

The current study was carried out to (1) evaluate premixed bioceramic (BC) and mineral trioxide aggregate (MTA) sealing properties in a laboratory and (2) compare the performance of these two materials in repairing an immediate iatrogenic furcal perforation of primary molars both clinically and radiographically.

MATERIALS AND METHODS

In vitro sections including eighty mandibular second primary molars were sorted into 4 equal groups: (1) an intact furcation area group, (2) an artificial perforation group (unrepaired), (3) an artificial perforation group repaired with MTA, and (4) an artificial perforation group repaired with premixed BC. The dye extraction method was used to assess the sealing ability of the material. Clinically, the study was designed as an equivalent parallel randomized controlled trial. Seventy-six mandibular second primary molars with immediate furcal perforation were sealed with MTA and premixed BC. Teeth were evaluated clinically and radiographically at 3, 6, and 12 months.

RESULTS

Although the difference was statistically insignificant (p = 0.058), the premixed BC group had better sealing ability than the MTA group [mean difference = 0.020; 95% CI (-0.001, 0.040)]. Clinically and radiographically, the two materials had an equivalent success rate in the first 3 months [ARR = 0.05; 95% CI (-0.07, 0.17)] but inequivalent success rates at 6 and 12 months with premixed BC performing better than MTA.

CONCLUSIONS

The present findings confirm that premixed BC is a promising material that can be used to repair a furcal perforation of primary molars. Premixed BC has better sealing properties and better performance at the clinical and radiographic levels than MTA.

CLINICAL RELEVANCE

(1) Accidental furcal perforation in primary molars is one of the worst problems that results in diminishing the lifetime expectancy of primary teeth if not properly treated. Though new BC repair materials have been introduced to enhance healing and tissue inductive properties, there is an obvious shortage in clinical trials covering this area. The present study is a premier study that assesses a recently introduced premixed BC material in the furcal perforation of primary teeth and compares its outcomes with those of the widely used MTA.

TRIAL REGISTRATION

ClinicalTrials.gov PRS reference #NCT04137861.

In vivo Biocompatibility and Bioactivity of Calcium Silicate-Based Bioceramics in Endodontics

Endodontic therapy aims to preserve or repair the activity and function of pulp and periapical tissues. Due to their excellent biological features, a substantial number of calcium silicate-based bioceramics have been introduced into endodontics and simultaneously increased the success rate of endodontic treatment. The present manuscript describes the in vivo biocompatibility and bioactivity of four types of calcium silicate-based bioceramics in endodontics.