Effect of proanthocyanidin and bamboo salt on the push-out bond strength of an epoxy resin sealer to sodium hypochlorite-treated root dentin: An in vitro study

Effect of various irrigation protocols and antioxidant application on bonding performance of two adhesive systems to coronal dentin

Background

The aim was to evaluate the effect of different irrigation protocols and antioxidants application on the shear bond strength (SBS) of two different adhesive systems to deep coronal dentin at different temperature.

Material and Methods

One hundred and twenty human premolar teeth were cut longitudinally in two halves, then the prepared specimens were allocated into four main groups according to the irrigation protocols; Distilled water (control), Sodium hypochlorite (NaOCl) + Ethylenediamine Tetra-acetic Acid (EDTA), and NaOCl + Editronate (HEDP), two subgroups according to irrigation solutions temperature; 4°C and 37°C, two divisions according to grape seed extract (GSE) application (with and without), and two subdivisions according to the applied adhesive systems; OptiBond-All-In-One (OPT) and ScotchBond Universal (SBU). Adhesives were applied in self-etch (SE) mode and resin composite material discs were built. Specimens were kept in distilled water for 24-h at 37°C before SBS testing. Four-way ANOVA and Tukey HSD tests were used for data analysis (α=0.05).

Results

4°C irrigants solution temperature showed the least significant SBS values, distilled water group showed significantly higher SBS values compared to NaOCl + EDTA and NaOCl + HEDP groups respectively. GSE application improved dentin bond strength significantly within each adhesive.

Conclusions

Increasing the temperature of the irrigation solutions has significantly enhanced the SBS of coronal dentin. Antioxidants application following different irrigation protocols has improved the SBS. Key words:Irrigation protocols, temperature, bond strength, coronal dentin, antioxidant, adhesive systems.

The Effect of Antioxidants on Dentin Bond Strength after Application of Common Endodontic Irrigants: A Systematic Review

The purpose of this systematic review was to evaluate how an antioxidant treatment would influence the immediate bond strength of dental adhesives to endodontically treated dentine. Scientific evidence was researched in five databases using selected descriptors. Two independent reviewers conducted the investigation and assessed the data and methodological quality of the studies. Inclusion and exclusion criteria were specified for article selection; only studies in English and published between 2001 and 2022 were evaluated. A total of 18 studies were selected and analysed. According to most studies, the irrigation procedure and substrate preparation in endodontic therapy may affect the immediate bond strength. Antioxidants can improve bond strength and adhesion following the use of the most frequently used irrigants in root canal treatments. Therefore, antioxidant treatment can be considered a proper technique to enhance the bond strength of endodontically treated teeth.

Comparison of the push-out bond strength of AH Plus sealer to dentin after using different herbal irrigation solutions as the final rinse

The aim of the present study was to evaluate the push-out bond strength of AH Plus sealer to dentin treated with the essential oils of Cumimum cyminum and Cinnamomum zeylanicum as herbal final irrigants. Forty human mandibular first premolars were selected. After smear layer removal, the samples were divided into 4 groups and irrigated with experimental solutions for 1 min and later with distilled water. G1: Cinnamomum zeylanicum (CZ) in minimum inhibitory concentration (MIC); G2: Sodium hypochlorite 2.5%; G3: Sodium hypochlorite in MIC; G4: Cuminum cyminum (CC) in MIC. After obturation, the roots were sectioned in order to obtain 1-mm discs for push-out assessment. The push-out test was performed using a universal testing machine. The slices were examined using a stereomicroscope at 30× to determine the mode of failure. The data were analyzed using one-way analysis of variance and Tukey's post-hoc test. The teeth irrigated with CZ showed significantly lower push-out resistance than those irrigated with NaOCl 2.5% and NaOCl at MIC. The other groups had no significant difference. The modes of failure were predominantly mixed. Under the limitations of the present study, CC does not have adverse effects on the bond strength of AH Plus and can be used as a good alternative for currently used final irrigants.

The effect of natural reducing agents on push-out bond strength of AH plus and BioRoot RCS to sodium hypochlorite treated root dentin

Aims:

To evaluate the effect of natural anticoagulants 6.5% proanthocyanidin (PA) and 25% bamboo salt on push-out bond strength (PBS) of AH Plus and BioRoot RCS to dentin.

Subjects and Methods:

30 single-rooted extracted human teeth were collected. After establishing the working length samples were prepared up to size F3. 5 ml of 3% NaOCl was used as irrigant during instrumentation followed by rinse with 5 ml of 17% ethylenediaminetetraacetic acid. Samples were randomly divided into groups based on the final irrigation solution: Group I – AH plus sealer group, Ia – Saline group, Ib – PA group, Ic – Bamboo salt (BS) group. Group II – BioRoot RCS group, IIa – Saline group, IIb – PA group, IIc – BS group. After obturation, samples were embedded in self-cure acrylic resin and 2 mm thick root slices were made at coronal middle and apical 3^rd. These slices were subjected to PBS testing followed by stereomicroscopic examination for checking the mode of failure.

Statistical Analysis Used:

Kruskal–Wallis and Dunn's post hoc test.

Results:

3% NaOCl significantly decreased the bond strength of AH Plus as compared to BioRoot RCS to dentin (P < 0.05). Both PA and BS were capable of increasing the PBS of AH Plus and BioRoot RCS to NaOCl-treated dentin.

Conclusions:

Final irrigation with antioxidants such as PA and BS eliminates the risk of reduced bond strength of sealer to root canal walls, which ensues following the use of NaOCl as an irrigant.

Depth of Penetration and Antimicrobial Activity of 5% and 10% Bamboo Salt, 2% Chlorhexidine Gel and Calcium Hydroxide Against Enterococcus faecalis - An In Vitro Study

Objective:

E. faecalis is one of the most commonly found species in persistent and secondary infections associated with endodontic failure. This in vitro study aimed to evaluate the depth of penetration and antimicrobial efficacy of 5% and 10% bamboo salt (BS), 2% chlorhexidine gel (CHX) and calcium hydroxide (CH) against E. faecalis.

Methods:

E. faecalis was inoculated in dentine blocks for 21 days following which the antibacterial efficacy of the experimental medicaments were quantatively assessed by harvesting the dentinal debris from depths of 200 µm and 400 µm from the block lumen on the 2^nd and 7^th day. The depth of penetration of the medicaments was measured using LIVE/DEAD BacLight stain under CLSM.

Results:

Results showed that the medicaments had varying degrees of antimicrobial efficacy and depth of penetration. Among the medicaments, CHX showed the highest antimicrobial activity on both the time intervals (P<0.05), followed by 10% BS, 5% BS and the least efficacy was observed in CH group. CHX and 10% BS exhibited the highest depth of penetration, which was proximate to the penetration of E. faecalis.

Conclusion:

It can be concluded that 10% bamboo salt can serve as a viable natural antimicrobial in endodontic therapy.

Effect of nonthermal atmospheric plasma on the push-out bond strength of epoxy resin-based and bioceramic root canal sealers: An in vitro study

Aim:

The aim of this study was to evaluate the effect of nonthermal atmospheric plasma (NTAP) on the bond strength of epoxy resin-based and bioceramic root canal sealers.

Materials and Methods:

Freshly extracted forty (n = 40) single-rooted mandibular premolar teeth were divided into four groups (n = 10) based on the sealer used and NTAP application – Group 1: Epoxy resin-based sealer (AH Plus) without NTAP application, Group 2: Epoxy resin-based sealer (AH Plus) with NTAP application for 30 s, Group 3: Bioceramic sealer (BioRoot RCS) without NTAP application, and Group 4: Bioceramic sealer (BioRoot RCS) with NTAP application for 30 s. After NTAP application in Groups 2 and 4, all the samples were obturated using sealers according to their grouping protocols. Two-millimeter slices were obtained from each sample using hard tissue microtome, which were subjected to push-out bond strength (PBS) under the universal testing machine. Data were subjected to statistical analysis using one-way analysis of variance followed by the Post hoc tukey test. The level of statistical significance was set at P < 0.05.

Results:

The PBS values were observed to be significantly higher in bioceramic sealer with NTAP application (Group 4) followed by epoxy resin-based sealer with NTAP application (Group 2).

Conclusion:

NTAP application enhanced the PBS of bioceramic (BioRoot RCS) and epoxy resin-based (AH Plus) sealers compared to their control groups.