Effect of 17% ethylenediaminetetraacetic acid and 0.2% chitosan on pushout bond strength of biodentine and ProRoot mineral trioxide aggregate: An in vitro study

Effect of Chitosan Irrigant and Lubricating Gel on Bond Strength of Resin Sealer to Radicular Dentin: An In Vitro Study

BACKGROUND

The adhesive strength of sealers to dentin is influenced by various factors, and the presence of a smear layer is among the critical variables. Chitosan, known for its dentin compatibility, has previously demonstrated a reduction in dentin change and resin sealer bond strength comparable to ethylenediaminetetraacetic acid (EDTA) when used as an irrigant and final rinse. The study investigates the impact of chitosan, used as both a lubricating gel and final rinse, on the push-out bond strength of resin sealer.

MATERIALS AND METHOD

Forty single-rooted premolar teeth, each with a fully formed root and a single root canal, were collected post-extraction. During canal preparation, 1 ml sodium hypochlorite (3%) was used for irrigation at every change of instrument, followed by applying specific chelating gel and final rinse for each experimental group. The groups included: Group 1 (17% EDTA chelating gel, final rinse with saline), Group 2 (17% EDTA chelating gel, final rinse with 17% EDTA solution), Group 3 (chitosan chelating gel, final rinse with saline solution), and Group 4 (chitosan chelating gel, final rinse with 0.2% chitosan solution), 10 specimens in each group. After obturation, specimens were sealed and incubated for a week at 37°C with 100% humidity. The universal testing machine was used for push-out tests, and specimens were examined using a scanning electron microscope (SEM) to identify various types of bond failure.

RESULTS

Among the four groups, Group 2 exhibited the highest mean push-out bond strength (7.33 ± 0.26 MPa), followed by Group 4 (5.33 ± 0.25 MPa), Group 1 (4.61 ± 0.30 MPa), and Group 3 (2.94 ± 0.32 MPa). The variations in bond strength suggest a notable impact of the chelating agents and final rinse solutions on the resin sealer's interaction with dentin.

CONCLUSION

The study concludes that the use of EDTA as both a lubricating gel and a final rinse significantly enhances push-out bond strength, outperforming chitosan in this study. Groups with saline as the final rinse (Group 1 and Group 3) exhibited the least bond strength, highlighting the importance of the final rinse in root canal therapy.

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.

The comparative of chitosan and chitosan nanoparticle versus ethylenediaminetetraacetic acid on the smear layer removal: A systematic review and meta-analysis of in vitro study

The purpose of this systematic review of meta-analysis was to compare the effectiveness of removing the smearing layer using EDTA versus Chitosan (Ch) and Chitosan nanoparticles (Ch-NPs). A search was performed in four electronic databases (Web of Science, PubMed, Scopus, and Cochrane). The included studies were assessed by two reviewers using Joanna Briggs Institute's critical appraisal checklist for the quasi-experimental studies. Outcomes obtained by scanning electron microscopy (SEM) and conventional methods were presented as standardized mean differences alongside 95% confidence intervals. Seven investigations employed 212 single-root teeth. In the apical section (p = .317, 95% CI = -0.820 to 0.266, Tau2  = 0.387), middle segment (p = .914, 95% CI = -1.019 to 0.912, Tau2  = 1.027), and coronal segment (p = .277, 95% CI = -1.008 to 0.289, Tau2  = 0.378). This meta-analysis found no difference between Ch, Ch-NPs, and EDTA in removing the smear layer in the three segments. This systematic review is designed to show evidence related to the PICO question, in which our outcome is smear layer removal and not the clinical success of such a treatment. RESEARCH HIGHLIGHTS: The study aimed to compare the effectiveness of chitosan and chitosan nanoparticles with ethylenediaminetetraacetic acid (EDTA) in removing the smear layer, a layer of debris and organic material on the tooth surface, through a systematic review and meta-analysis. The removal of the smear layer is crucial for successful dental treatments, as it enhances the adhesion of restorative materials and improves the penetration of antimicrobial agents into dentinal tubules. The researchers conducted a systematic review and meta-analysis, searching various databases of electron microscopy results for relevant in vitro studies comparing the effects of chitosan or chitosan nanoparticles with EDTA on smear layer removal. The results encourage further exploration of chitosan and chitosan nanoparticles for clinical use in dentistry, while considering their specific applications and long-term effects.

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.

MTA-Enriched Polymeric Scaffolds Enhanced the Expression of Angiogenic Markers in Human Dental Pulp Stem Cells

Revascularization of the pulp tissue is one of the fundamental processes and challenges in regenerative endodontic procedures (REPs). In this regard, the current study is aimed at synthesizing the mineral trioxide aggregate- (MTA-) based scaffolds as a biomaterial for REPs. Poly (ε-caprolactone) (PCL)/chitosan (CS)/MTA scaffolds were constructed and evaluated by FTIR, SEM, XRD, and TGA analyses. Proliferation and adhesion of human dental pulp stem cells (hDPSCs) were assessed on these scaffolds by scanning electron microscopy (SEM) and MTT assays, respectively. The expression of angiogenic markers was investigated in gene and protein levels by real-time PCR and western blotting tests. Our results indicated that the obtained appropriate physicochemical characteristics of scaffolds could be suitable for REPs. The adhesion and proliferation level of hDPSCs were significantly increased after seeding on PCL/CS/MTA scaffolds. The expression levels of VEGFR-2, Tie2, and Angiopoietin-1 genes were statistically increased on the PCL/CS/MTA scaffold. In support of these findings, western blotting results showed the upregulation of these markers at protein levels in PCL/CS/MTA scaffold (P < 0.05). The current study results suggested that PCL/CS/MTA scaffolds provide appropriate structures for the adhesion and proliferation of hDPSCs besides induction of the angiogenesis process in these cells.

Effect of exposure to etidronic acid on the bond strength of calcium silicate-based cements after 1 and 21 days: an in vitro study

Background

After reparation of root perforations with calcium silicate-based cements (CSBC), the surface of the material is expected to be exposed to root canal irrigants (RCI) while resuming the root canal treatment.

Methods

The aim of this study was to compare the effect of exposure to a mixture of sodium hypochlorite (NaOCl) and etidronic acid (HEBP) or other irrigants on the Push Out Bond Strength (POBS) of CSBC after two different setting times. 240 root slices 1 mm thick were obtained from single-rooted human teeth. A 1.4 mm diameter perforation was performed on each slice and filled with Biodentine (BD) or ProRoot MTA (PMTA). After 1 or 21 days they were exposed to 17% ethylenediaminetetraacetic acid, 5.25% NaOCl, a mixture of 5.25% NaOCl and 9% HEBP (NaOCl + HEBP) or saline (n = 15) and submitted to a push-out test. POBS results were analysed with ANOVA and Tukey tests.

Results

BD showed higher POBS than PMTA after 1 day (p < .05). After 21 days no differences were found between materials. After 1 day exposure to NaOCl + HEBP resulted in higher POBS, compared to the other irrigants (p < .05).

Conclusion

POBS results are influenced by the cement, the setting time and the exposure to irrigants.

Bone and Cartilage Interfaces With Orthopedic Implants: A Literature Review

The interface between a surgical implant and tissue consists of a complex and dynamic environment characterized by mechanical and biological interactions between the implant and surrounding tissue. The implantation process leads to injury which needs to heal over time and the rapidity of this process as well as the property of restored tissue impact directly the strength of the interface. Bleeding is the first and most relevant step of the healing process because blood provides growth factors and cellular material necessary for tissue repair. Integration of the implants placed in poorly vascularized tissue such as articular cartilage is, therefore, more challenging than compared with the implants placed in well-vascularized tissues such as bone. Bleeding is followed by the establishment of a provisional matrix that is gradually transformed into the native tissue. The ultimate goal of implantation is to obtain a complete integration between the implant and tissue resulting in long-term stability. The stability of the implant has been defined as primary (mechanical) and secondary (biological integration) stability. Successful integration of an implant within the tissue depends on both stabilities and is vital for short- and long-term surgical outcomes. Advances in research aim to improve implant integration resulting in enhanced implant and tissue interface. Numerous methods have been employed to improve the process of modifying both stability types. This review provides a comprehensive discussion of current knowledge regarding implant-tissue interfaces within bone and cartilage as well as novel approaches to strengthen the implant-tissue interface. Furthermore, it gives an insight into the current state-of-art biomechanical testing of the stability of the implants. Current knowledge reveals that the design of the implants closely mimicking the native structure is more likely to become well integrated. The literature provides however several other techniques such as coating with a bioactive compound that will stimulate the integration and successful outcome for the patient.

Effect of exposure to root canal irrigants on the push-out bond strength of calcium silicate-based cements

OBJECTIVES

The aim of this study was to compare the push-out bond strength (POBS) of three calcium silicate-based cements (CSBC) after exposure to saline, sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA), and a mixture of NaOCl and etidronic acid (NaOCl+HEBP) in simulated perforation.

MATERIALS AND METHODS

A total of 180 dentin slices were perforated and then filled with either Biodentine (BD), ProRoot MTA (PMTA), or Total Fill (TF). After 1 week, specimens in each group were divided into 4 subgroups (n = 15) according to the root canal irrigant (RCI) that their coronal surface was exposed to: saline, 5.25% NaOCl, 17% EDTA, or a mixture of 5.25% NaOCl and 9% HEBP (NaOCl+HEBP). A push-out test was performed, and the failure pattern was assessed. POBS data were analyzed with ANOVA and Tukey post hoc tests and the failure patterns with chi-square test.

RESULTS

No differences were found when comparing the effect of RCI on the POBS of PMTA. BD showed significantly higher POBS values after exposure to NaOCl+HEBP (p < .05), and those of TF were significantly lower after exposure to EDTA (p < .05). No differences in the failure patterns were found among groups.

CONCLUSION

NaOCl+HEBP had no detrimental effect on the POBS of CSBC.

CLINICAL RELEVANCE

The mixture of sodium hypochlorite and etidronic acid may be considered as an alternative irrigant when treating root perforations.