Physicochemical Properties of Two Generations of MTA-Based Root Canal Sealers

In vitro evaluation of antimicrobial photodynamic therapy with photosensitizers and calcium hydroxide on bond strength, chemical composition, and sealing of glass-fiber posts to root dentin

Investigate the impact of antimicrobial photodynamic therapy (aPDT) using different photosensitizers (PSs) such as indocyanine green (IG), curcumin (CC), and methylene blue (MB), with or without intracanal application of calcium hydroxide (CH), on the push-out bond strength of glass-fiber posts (GFPs) to intraradicular dentin, the chemical composition of the root substrate, and the sealing of the adhesive interface across different thirds of intraradicular dentin. A total of 112 bovine teeth underwent biomechanical preparation and were divided into eight experimental groups (n = 14 each): Negative control with deionized water; positive control with deionized water + CH; IG group with indocyanine green and infrared laser; IG + CH group; CC group with curcumin and blue LED; CC + CH group; MB group with methylene blue and red laser; and MB + CH group. The push-out bond strength was measured using a universal testing machine (n = 8), and scanning electron microscopy characterized the fracture patterns. Energy dispersive spectroscopy (n = 3) analyzed the chemical composition of the dentin substrate, while fluorescence confocal microscopy (n = 3) assessed the adhesive interface sealing between the resin cement and root dentin. Data were analyzed using two-way repeated measures ANOVA and the Tukey test for push-out bond strength and chemical composition comparison, with the Kruskal-Wallis and Dunn's tests (α = 0.05) for adhesive interface sealing. Significant bond strength differences were noted across root thirds and experimental groups (P < .05), with the IG + CH group showing the highest cervical bond strength and the IG group the lowest. Apical bond strength was highest in the CC group but lower in the NC and PC groups. Mixed failures predominated, except in the MB + CH group, where adhesive failures prevailed. Elemental composition varied among groups treated with different PSs and CH (P < .05), but interface quality, tag formation, and penetration depth showed no significant differences (P > .05). Laser-activated 500 mg/L CC combined with CH emerged as a clinically relevant option for root canal decontamination before GFPs luting. aPDT with different PSs and root canal depth influenced the push-out bond strength of GFPs and the chemical composition of root dentin. Curcumin-mediated aPDT at 500 mg/L proved effective, enhancing bond strength and sealing while maintaining consistent dentin composition across depths.

Postobturation Pain of three Novel Calcium Silicate-based sealers with asymptomatic irreversible pulpitis or necrotic pulp with chronic apical periodontitis: prospective clinical trial

BACKGROUND

Bioceramic-based root canal sealers are increasingly important in root canal treatment because of their biocompatible properties. This study aimed to evaluate postobturation pain incidence and intensity after root canal obturation with NeoSealer Flo, MTA-Bioseal, and GuttaFlow bioseal calcium silicate-based sealers and AH Plus epoxy resin-based sealer in patients with asymptomatic irreversible pulpitis or necrotic pulp with chronic apical periodontitis.

METHODS

A total of 120 participants with single-rooted teeth were included and randomly divided into four groups according to the root canal sealer used (n = 30). The patients were subsequently categorised based on the pulp vitality (vital or nonvital) in each group (n = 15) and all teeth were obturated in a single-visit. The postobturation pain scores were recorded on a visual analogue scale (VAS) at 6 h, 24 h, 48 h, 72 h, 7 d and 30 d. Moreover, analgesic intake was also noted at 24 h and 48 h. The Mann-Whitney U test, Kruskal‒Wallis H test, Friedman test, and Spearman's correlation test were used, and a p value < 0.05 was considered significant.

RESULTS

VAS scores were highest for the 6 h > 24 h > 48 h ≈ 72 h ≈ 7 d ≈ 30 d time intervals for both pulp status in each root canal sealer. A significant decrease in the VAS score was observed for all sealers from 6 h to 48 h (p 0.05). Nonvital cases had lower VAS scores at all time intervals. Analgesic intake was greater in the first 24 h (p < 0.05) in vital cases (p < 0.05) and also in females than males.

CONCLUSION

The level of pain experienced after obturation was similar in patients with different pulp status for all the root canal sealers. Analgesic intake was greater in vital cases and females within 24 h.

TRIAL REGISTRATION

ClinicalTrial.gov , NCT06515756, record date: 2024-07-17, retrospectively registered.

Comparative Analysis of Interfacial Adaptation and Depth Penetration of Recent HiFlow versus Regular Bioceramic Sealers in Conjunction with BC Gutta-Percha Points Using Two Different Obturation Techniques-A Preliminary Report of an Ex Vivo Study

This study aimed to assess the adaptability and penetration depth capacity of recent bioceramic systems, including regular EndoSequence (BC) versus HiFlow (BCH) sealers in the presence of BC points. A total of 54 single-rooted teeth were instrumented and obturated with either the cold or warm compaction technique (n = 9), using either BC, BCH, or AH Plus (AHP) combined with BC points. The adaptation, film thickness, and gaps/voids were evaluated by scanning electron microscopy. The sealer/dentin interface was evaluated by Raman spectroscopy, and depth penetration was evaluated by a confocal laser scanning microscope. According to the normality test, the data were statistically analyzed by ANOVA or Kruskal-Wallis and Mann-Whitney U tests at p < 0.05. BCH sealer showed the significantly thinnest film with the greatest flow (p > 0.001), with further improvement when subjected to the warm compaction technique. Moreover, it exhibited close adaptation with deep penetration into radicular dentin, forming a tag-like structure. The Raman spectra also indicated close contact with the dentin surface. The use of BC sealer with BC points exhibited homogenous, single-unit obturation, either with a cold or warm technique. Furthermore, the use of the warm compaction technique with BCH sealer achieved a gap-free interface associated with tag-like structures, which exhibit the monoblock phenomenon.

Stereomicroscopic evaluation of sealing ability of four different root canal sealers: an in-vitro study

AIM

To compare and evaluate the sealing ability of four different commercially available sealers to provide seal against the dye penetration test using a stereomicroscope-an in-vitro study.

MATERIAL/METHOD

80 extracted single rooted mandibular premolar with single canal were used in this study. The samples were divided in 4 groups (20 in each) based on sealer. Group I (Diaproseal), Group II (apexit Plus), Group III (MTA Fillapex) and Group IV (Bio-C). The samples were analyzed using a stereomicroscope and data analysis was done with one-way Anova And post hoc Tukey's test.

RESULT

The mean dye penetration score was 1.2400 ± 0.778 mm for Group I. 2.6000 ± 0.897 mm for Group II, 4.2000 ± 0.923 mm for Group III and 4.225 ± 2.055 mm for Group IV. One-way Anova analysis shows that intergroup comparison was statistically significant between the four groups. The post hoc Tukey's test reveals that the difference was statistically non-significant between group III and group IV.

CONCLUSION

It was concluded that between the four groups the Group I (Diaproseal) showed the least dye penetration followed by Group II (Apexit Pus), Group III (MTA Fillapex) and then Group IV (Bio-C), where there was no significant difference between the Group III (MTA Fillapex) and Group IV (Bio-C).

Physicochemical properties of AH plus bioceramic sealer, Bio-C Sealer, and ADseal root canal sealer

BACKGROUND

The aim of this study was to evaluate the physicochemical properties of two newly introduced premixed calcium silicate-based root canal sealers (AH Plus Bioceramic Sealer and Bio-C Sealer) compared to a resin-based root canal sealer (ADseal root canal sealer).

METHODS

Solubility, pH analysis, calcium ion release, and film thickness of each sealer were evaluated following ISO guidelines. The data were examined using the two-way ANOVA test. Furthermore, X-ray diffraction (XRD) examination was performed to investigate the crystalline phase of each type of sealer. X-ray fluorescence (XRF) analysis was done for the chemical elemental analysis of each sealer.

RESULTS

The least film thickness, highest alkalinity, and highest calcium ion release were all displayed by AH Plus Bioceramic Sealer. High solubility, high alkalinity, intermediate calcium ion release, and intermediate film thickness were all displayed by Bio-C Sealer. While ADseal root canal sealer displayed the greatest film thickness, least solubility, alkalinity, and calcium ion release.

CONCLUSIONS

Both AH Plus Bioceramic Sealer and Bio-C Sealer represented adequate properties to be considered a good sealer that could be used as a potential alternative to resin-based root canal sealers.

Hydration Characterization of Two Generations of MTA-Based Root Canal Sealers

Since the setting characterization of a root canal sealer has an impact on its biological behavior of final obturation, this study evaluated the setting characterization of mineral trioxide aggregate MTA-Fillapex versus MTA-Bioseal compared with epoxy resin (Adseal) root canal sealers. Freshly mixed sealer was inserted into the mold (n = 10). The initial and final setting times were evaluated using a Vicat needle and were then statistically analyzed by one-way ANOVA at p < 0.05. The raw pastes and the stages of the setting reaction were analyzed using Fourier Transform Infrared (FTIR) Spectroscopy. The phase compositions were evaluated using X-ray diffraction (XRD). A significant and fast setting time was recorded by Adseal (4.7 ± 0.46 h) followed by MTA-Bioseal (11.4 ± 1.34 h) at p < 0.001. The MTA-Fillapex did not set completely in three months. The FTIR and XRD of both MTA-Bioseal and Adseal detected bands of the polymerized phases, while those of MTA-Fillapex detected partial polymerization with a low percentage of polymerized silica. MTA-Bioseal and Adseal met the ISO standards for setting times. However, MTA-Fillapex did not fulfill the ideal requirement for the sealer. Although the raw pastes of both MTA-sealers had nearly similar compositions, they behaved differently during the hydration reaction. MTA-Bioseal set completely, while MTA-Fillapex was not completely set.