Effect of Glycolic Acid, Maleic Acid, and EDTA in the Removal of Smear Layer from Root Canal Dentin

Objective: To assess the efficacy of 5% Glycolic Acid (GA), 17% ethylenediaminetetraacetic acid (EDTA) and 7% maleic acid (MA), in removing the smear layer (SL). Material and Methods: For the experiment, forty single-rooted human teeth were selected. To perform the chemo‑mechanical preparation, the root canals were instrumented to an apical size of #30, along with simultaneous irrigation of 2.5% NaOCl. The samples were allotted to the experimental groups based on the final irrigating solution (n=10): (1) The GA group: 05%, (2) the EDTA group: 17%, (3) the MA group: 7%, and (4) the control group: Distilled water. The teeth were evaluated for the presence or absence of SL using SEM. Results:Comparing the 5% GA, 7% MA and 17% EDTA groups, no statistically significant differences were found at the coronal and middle thirds (p>0.05). However, in the apical third, MA had greater efficacy than EDTA (p=0.002) and GA (p=0.041), with a significant difference in the SL removal, while there was no significant difference between the latter (p=0.148). Conclusion: Thus, it was concluded that 7% maleic acid as a final irrigating solution is more efficacious than 17% EDTA and 5% glycolic acid in eliminating the smear layer from the apical portion of the root canal

Does radiation therapy affect adhesion of tricalcium silicate cements to root dentin?

Objective: This study aimed to analyze the effect of irradiation on the push-out bond strength of mineral trioxide aggregate (MTA) and Biodentine to radicular dentin. Methodology: A total of 60 extracted mature human teeth with single root canals were categorized into two groups (irradiated and non-irradiated) (n=30). Each group was further divided into two sub-groups based on cements used (Biodentine and MTA). Then, a cumulative radiation dose of 60 Gy was divided into 30 fractions (two Gy for every fraction) and administered for five successive days per week over six weeks. Obturation was then performed using MTA and Biodentine. Afterwards, 1.5 mm thick horizontal sections were procured from the middle one-third of all the specimens and then subjected to push-out bond test. Results were analyzed using one-way analysis of variance with post-hoc Tukey’s test. Results: The bond strength of Biodentine and MTA to irradiated teeth was lower than non-irradiated teeth. Highest push-out bond strength was observed in non-irradiated specimens filled with Biodentine (p=0), followed by irradiated specimens filled with Biodentine (p=0); non-irradiated specimens filled with MTA (p=0); and irradiated specimens filled with MTA (p=0.9). Conclusion: The push-out bond strength of Biodentine and MTA to root canal dentin decreased significantly post irradiation

Evaluation of Sealing Ability of Biodentine to Root-End Cavities Irrigated either with Maleic Acid or Irritrol Using Glucose Filtration Model

Objective: To compare the effect of Maleic acid and Irritrol (combination of Chlorhexidine & Ethylenediaminetetraacetic acid) irrigation on the sealing ability of Biodentine when used as root-end filling material. Material and Methods: Thirty single-rooted human premolars were subjected to standardized root canal instrumentation and were irrigated with 2.5% Sodium Hypochlorite (NaOCl) after each instrument change. Apical root resections were done by removing 3 mm of the apex at a 90° angle to the long axis of the root with a diamond bur. The root end cavity preparation was done using ultrasonic tips at a low power setting under water coolant. They were randomly divided into 3 groups (n=10). Group 1 was irrigated with 7% Maleic acid, Group 2 was irrigated with Irritrol, and Group 3 was irrigated with 0.9% Saline (Control). Then, the root end cavities of all the samples were restored with Biodentine and were subjected to leakage analysis using a glucose filtration test. The mean values for each group were calculated and the obtained data was statistically analysed using ANOVA with post-hoc Tukey’s test, ANOVA with post-hoc Games-Howell test and repeated measures ANOVA with post-hoc Bonferroni test. Results: The specimens irrigated with Irritrol showed least microleakage as compared to 7% Maleic acid and 0.9% Saline. Conclusion: A regimen involving irrigation of the root-end cavity with Irritrol followed by root-end filling with Biodentine can improve the apical seal

Does radiation therapy affect adhesion of tricalcium silicate cements to root dentin?

Abstract Objective This study aimed to analyze the effect of irradiation on the push-out bond strength of mineral trioxide aggregate (MTA) and Biodentine to radicular dentin. Methodology A total of 60 extracted mature human teeth with single root canals were categorized into two groups (irradiated and non-irradiated) (n=30). Each group was further divided into two sub-groups based on cements used (Biodentine and MTA). Then, a cumulative radiation dose of 60 Gy was divided into 30 fractions (two Gy for every fraction) and administered for five successive days per week over six weeks. Obturation was then performed using MTA and Biodentine. Afterwards, 1.5 mm thick horizontal sections were procured from the middle one-third of all the specimens and then subjected to push-out bond test. Results were analyzed using one-way analysis of variance with post-hoc Tukey’s test. Results The bond strength of Biodentine and MTA to irradiated teeth was lower than non-irradiated teeth. Highest push-out bond strength was observed in non-irradiated specimens filled with Biodentine (p=0), followed by irradiated specimens filled with Biodentine (p=0); non-irradiated specimens filled with MTA (p=0); and irradiated specimens filled with MTA (p=0.9). Conclusion The push-out bond strength of Biodentine and MTA to root canal dentin decreased significantly post irradiation

Evaluation of cytotoxicity and antibacterial activity of a new class of silver citrate-based compounds as endodontic Irrigants

In the present study, the cytotoxicity and the antimicrobial activity of two silver citrate-based irrigant solutions were investigated. Cytotoxicity of various concentrations (0.25%, 0.5%, 1%, 2.5%, 5%) of both solutions (BioAKT and BioAKT Endo) was assessed on L-929 mouse fibroblasts using the MTT assay. For the quantitative analysis of components, an infrared (I.R.) spectroscopy was performed. The minimum inhibitory and minimal bactericidal concentrations (M.I.C. and M.B.C., respectively) were ascertained on Enterococcus faecalis strain ATCC 4083. For biofilm susceptibility after treatment with the irrigating agent, a minimum biofilm eradication concentration (M.B.E.C.) and confocal laser scanning microscope (C.L.S.M.) assays were performed. Quantification of E. faecalis cell biomass and percentage of live and dead cells in the biomass was appraised. Normality of data was analyzed using the D’Agostino & Pearson’s test and the Shapiro–Wilk test. Statistical analysis was performed using one-way analysis of variance (ANOVA) and Tukey’s test. Both silver citrate solutions showed mouse fibroblasts viability >70% when diluted to 0.25% and 0.5%. Conversely, at higher concentrations, they were extremely cytotoxic. F.T.-IR spectroscopy measurements of both liquids showed the same spectra, indicating similar chemical characteristics. No substantial contrast in antimicrobial activity was observed among the two silver citrate solutions by using broth microdilution methods, biofilm susceptibility (MBEC-HTP device), and biomass screening using confocal laser scanning microscopy (C.L.S.M.) technique. Both solutions, used as root canal irrigants, exhibited significant antimicrobial activity and low cytocompatibility at dilutions greater than 0.5%

Evaluation of Two Different Types of Mineral Trioxide Aggregate Cements as Direct Pulp Capping Agents in Human Teeth

Traumatic human dental injuries involving the pulp might necessitate direct capping procedures. This clinical study aimed to analyse the histological outcomes using two different direct capping materials. Twenty patients with bilateral premolars, scheduled for orthodontic extraction, were selected. The teeth were treated either using ProRoot MTA or RetroMTA. All patients were recalled after 30 and 60 days for teeth extraction. The histopathologically stained specimens were blindly evaluated using hard tissue bridge formation, inflammatory reaction and pulpal findings criteria. Data were evaluated statistically. Results: After 60 days, only the parameter for hard tissue bridge formation showed significant difference in the ProRoot MTA group (p = 0.010), while both direct capping materials performed similarly regarding inflammatory pulp reaction and pulpal findings. Although, during the first 30 days, RetroMTA presented better results in terms of continuity, morphology, hard tissue bridge localisation, and extension/general state of the inflammatory reaction, the continuity was better at 60 days when ProRoot MTA was applied. Treatment with RetroMTA healed the pulpal tissue faster compared with ProRoot MTA but it seemed to be rather a reparative process