Bond strength of root canal filling with radicular dentin previously treated with either photobiomodulation or photodynamic therapy: Effect of disinfection protocols

The use of sonic and ultrasonic activation of endodontic sealer to improve sealer filling quality in the root canal: a scoping review

This scoping review aimed to map whether the use of sonic and ultrasonic methods to activate the endodontic sealer improves the sealer filling quality in the root canal, considering the bond strength and intratubular penetration to the root dentin as evaluation criteria. The study protocol was prospectively registered and is available online ( https://osf.io/x5fma/ ). Reporting was based on PRISMA Extension for Scoping Reviews. The search was performed in Embase, PubMed, Scopus, and Web of Science. We selected studies without time and language restrictions that used sonic or ultrasonic methods to activate endodontic sealer, whose outcomes were bond strength and intratubular penetration. Three researchers independently selected the articles and collected data. Of 1422 articles, 19 were read in full and 13 studies were included. The vast majority of studies opted for direct activation of the endodontic sealer. The most investigated sealers were the epoxy resin-based sealers, and the ultrasonic activation method was the most explored. For the bond strength outcome, there was a trend toward higher values when the sealer was activated ultrasonically, but the findings seem to be divergent. The sonic activation was not effective for its intended purpose. For the outcome of intratubular penetration, the vast majority of studies indicate that the use of sonic and ultrasonic methods to activate the endodontic sealer is capable of increasing intratubular penetration. The use of sonic and ultrasonic methods to directly activate the endodontic sealer can increase the intratubular penetration of the sealer, but their benefits on the bond strength are uncertain.

Effect of Laser Photobiomodulation on Postoperative Pain in Endodontics: A Systematic Review

Objective: Photobiomodulation therapy has proven benefits in various dental treatments. The current systematic review aims to explore the role of laser photobiomodulation in modulating postoperative pain followed by endodontic treatment. Methods: In this systematic review, randomized controlled clinical trials on low-level laser therapy/photobiomodulation in endodontic therapy were analyzed. Database search was performed in PubMed/Medline, Web of Science, Scopus, and Cochrane Library, followed by literature search in Google Scholar. Results: A total of 12 studies were included as per the set criteria. The included studies utilized diode laser (808-970 nm) and indium gallium aluminum. All the included studies evaluated postendodontic pain after root canal therapy and endodontic surgery. A majority of the included studies showed significant benefits of photobiomodulation in postoperative pain management in endodontic therapy.Heterogeneity of the laser parameters and lack of power calculations for sampling among the included studies preclude solid recommendation of use of photobiomodulation therapy (PBMT) for postendodontic pain management. Conclusions: Although PBMT has proven potential benefits being a possible adjunct in postoperative pain management in endodontic therapy, it requires robust standardized randomized control trials to confirm the results of the systematic review.

Effectiveness of Morinda Citrofolia, Sapindus Mukorossi, and Curcumin used in curry spice, to the radicular canal irrigant in improving bond integrity of glass fiber post

AIM

Evaluation of the push-out bond strength (PBS) of glass fiber reinforced post (GFRP) bonded to root dentin after canal disinfection using food-based root canal irrigants i.e., Curcumin photosensitizer (CP), Riboflavin photosensitizer (RFP), Morinda Ctrifolia juice (MCJ) and Sapindus Mukorossi (SM) along with MTAD as a final irrigant.

MATERIAL METHODS

Fifty human single-rooted premolar teeth were decoronated. Endodontic preparation was performed along with 2.25% sodium hypochlorite NaOCl solution followed by EDTA solution. Canals were dried and obturated followed by post-space preparation by removing GP. Specimens were allocated into five groups based on different food-based disinfection regimes (n= 10). Group 1: 2.25% NaOCl + MTAD (Control), Group 2: 6% MCJ + MTAD, Group 3: SM + MTAD, Group 4: CP + MTAD and Group 5: RFP + MTAD. All GFRP were bonded to radicular dentin. Root sectioning was performed followed by PBS and failure analysis using a universal testing machine (UTM) and stereomicroscope respectively. The data were analyzed using a one-way analysis of variance (ANOVA) test and the Post Hoc Tukey HSD test (p=0.05).

RESULTS

Samples disinfected with(MCJ+MTAD) at coronal third demonstrated maximum PBS (9.41±0.51 MPa). However, the apical third of group 5 (RFP + MTAD) exhibited the minimum values (4.06±0.23 MPa). Intergroup comparison analysis unveiled that group 2 (MCJ +MTAD) and group 3 (SM+MTAD) displayed comparable outcomes of PBS at all three-thirds. Similarly, samples in group 1 (2.25% NaOCl+ MTAD), group 4 (CP + MTAD), and group 5 (RFP + MTAD) exhibited comparable PBS.

CONCLUSION

Fruit-based irrigants Morinda Citrifolia and Sapindus Mukorossi have the potential to be used as root canal irrigants with a positive influence on bond strength.

Influence of antimicrobial photodynamic therapy on the bond strength of endodontic sealers to intraradicular dentin: A systematic review and meta-analysis

BACKGROUND

The objective of this systematic review and meta-analysis (SRMA) was to investigate the influence of antimicrobial photodynamic therapy (aPDT) on the bond strength of endodontic sealers to intraradicular dentin.

METHODS

This SRMA followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and was registered in the International Prospective Registry of Systematic Reviews (PROSPERO) (CRD42022319856). A population, intervention, control, and outcome (PICO) question was formulated: "Does antimicrobial photodynamic therapy decrease the bond strength of root canal sealers?". A literature search was performed in PubMed/MEDLINE, Embase, Web of Science, Scopus, Cochrane Library, and ProQuest databases until July 2022. Joanna Briggs Institute Critical Assessment Guidelines for Quasi-Experimental Studies were used for quality assessment. The meta-analysis was based on the inverse variance (IV) method (p<0.05).

RESULTS

Out of an initial 345 articles, 8 in vitro studies were included, published between 2013 and 2022. The studies were qualitatively analyzed; two studies showed a positive effect, two studies a negative effect, and the other studies showed no effect on bond strength of endodontic sealers to intraradicular dentin. Seven of the studies were included in the SRMA, which indicated that there was no significant difference in bond strength when using aPDT (P = 0.90; MD: -0.03; 95% CI: -0.46 to -0.41). There was a high level of evidence for each meta-analysis outcome.

CONCLUSION

It can be concluded that the use of aPDT as a method of root canal disinfection does not negatively influence the bond strength of endodontic sealers in the root canal.

Impact of antimicrobial photodynamic therapy on the bond-strength and penetration of endodontic sealers: A systematic review

BACKGROUND

Antimicrobial photodynamic therapy (aPDT) has been used for the disinfection of root canals. Studies have been carried out on its effect on the bond-strength and penetration of endodontic sealers. The aim of this systematic review is to critically analyze the literature and summarize the outcomes of these studies.

MATERIALS AND METHODS

An electronic search was conducted on research databases PubMED/Medline, ISI Web of Knowledge, Embase, Scopus and Europe PMC using the following the medical subject headings (MeSH) terms and keywords: [((endodontic sealer) OR (endodontic sealant) OR (root canal sealer)) AND ((anti-microbial photodynamic therapy) OR (laser-assisted) OR (light-assisted) OR (photosensitive dye) OR (photosensitizer)) AND ((bond-strength) OR (penetration))] for all literature published from inception to September 2022. Clinical studies, animal studies, laboratory investigations and case reports were included. Data was extracted and the quality of the included studies was assessed.

RESULTS

Of the 204 studies screen initially, 12 laboratory studies were included in this review. Majority of the outcomes revealed that aPDT does not have an adverse impact on the bond-strength or sealer penetration. Furthermore, AH Plus (an epoxy-based sealer) resulted in higher bond-strengths than other types of sealers (MTA Fillapex, Sealapex and Bioceramics). 11 studies were graded as having 'medium' quality and one study was graded as 'low'.

CONCLUSION

Within the limitations of this review, aPDT does not have a significant impact on the bonding and penetration of endodontic sealers. Future studies should focus on standardization and optimization of aPDT procedures when assessing their impact on the interaction between sealers and dentine.

Global research trends on photodynamic therapy in endodontics: A bibliometric analysis

BACKGROUND

Photodynamic therapy (PDT) is an adjunctive treatment that aims to inactivate microorganisms through an oxidative reaction produced by irradiating a photosensitizing agent. The quest for improved root canal disinfection has sought supplementary methods when performing chemomechanical procedures. From this perspective, PDT protocols were proposed as an auxiliary approach in endodontics. Thus, the aim of this study was to investigate publication metrics and research trends related to this scope.

METHODS

This review is reported in accordance with the PRISMA 2020 recommendations. Two blinded and independent reviewers systematically searched five electronic databases until December 2021. The acquired bibliometric parameters were analyzed through descriptive statistics and graphical mappings with VOSViewer software.

RESULTS

The search retrieved 342 studies from 84 journals originating from 33 countries. About 85% of the included studies were published over the last decade. Most of the available evidence is laboratory-based (74.5%), and the main clinical outcomes evaluated were microbiological load reduction and postoperative pain. Mayram Pourhajibagher is the researcher with the most publications as the first author (n = 16). Tehran University of Medical Sciences carried out the highest number of studies (n = 29), and Photodiagnosis and Photodynamic Therapy is the journal that most published on the theme (n = 111).

CONCLUSIONS

This bibliometric analysis mapped and discussed the scientific progress and publication metrics in PDT in endodontic research. Additionally, future perspectives were highlighted and should focus on discovering new photosensitizer agents, standardizing optimal photoactivation protocols, and conducting more clinical-oriented research.

Adjunctive use of Er, Cr: YSGG laser, Potassium titanyl Phosphate laser, and photosensitizer on extrusion bond strength of radicular dentin to bioceramic sealers

AIM

To assess the impact of adjunctive final root canal disinfection regime curcumin photosensitizer (CP) activated by Photodynamic therapy (PDT), Er, Cr: YSGG laser (ECL), and Potassium titanyl Phosphate (KTP) laser on the bond integrity of two endodontic Bioceramic (BC) sealers.

MATERIALS AND METHOD

Decoration of eighty human single-rooted teeth was performed up to a cementoenamel junction. After instrumentation, all samples were irrigated with 2.25% NaOCl solution followed by 17% EDTA. The specimens were divided arbitrarily into 8 groups (n = 10) based on the adjunctive final irrigation method used. Group 1 and 5 (Control): No adjunctive regime, cleaned using 2.25% NaOCl + 17% EDTA, group 2 and group 6: CP activated by PDT, Group 3 and Group 7 using ECL, Group 4 and Group 8: KTP laser. Following disinfection samples in groups 1, 2, 3, and 4 were obturated using Sankin apatite root canal sealer (SARS). Specimens in groups 5, 6, 7, and 8 were obturated using Pro-root endo sealer (PRES). Sectioning of samples was performed. The sectioned specimens were subjected to a compressive loading exerted via a steel plunger moving at a 0.5 mm/min crosshead speed till debonding. Means and standard deviations (SD) of EBS of BC sealer with the root canal dentin were assessed using one-way analysis of variance (ANOVA) and Post Hoc Tukey multiple comparison tests. The level of significance was measured at p = 0.05.

RESULTS

The coronal section of samples in group 5 (Na-E-PRES) exhibited the highest bond value. The lowest PBS was displayed by the middle third of specimens in group 6. Group 1 (Na-E-SARS), group 3 (Na-E-ECL-SARS), group 5 (Na-E-PRES), and group 7 (Na-E-ECL-PRES) exhibited comparable bond values (p>0.05). Whereas, group 2 (Na-E-PDT-SARS) and group 4 (Na-E-PTPL-SARS), group 6 (Na-E-PDT-PRES), and group 8 (Na-E-PTPL-PRES) were found to be comparable (p>0.05).

CONCLUSION

Adjunctive use of Er, Cr: YSGG laser displayed better extrusion bond strength with BC root canal sealer compared to CP activated by PDT and KTP laser. Bond strength is influenced by the type of irrigation.

Extrusion bond strength of glass fiber post to radicular dentin after final irrigation using MTAD, EDTA, Pineapple peel extract, and riboflavin

INTRODUCTION

The present study aims to determine the effect of different post-space final irrigants ethylenediaminetetraacetic acid (EDTA), a mixture of Doxycycline citric acid and detergent (MTAD), Riboflavin (RF) and Pineapple peel extract (PPE) on the bond integrity of GFPs bonded to radicular dentin.

MATERIALS AND METHODS

Crowns of forty human mandibular premolars teeth were sectioned up to cementoenamel junction CEJ. Root canal treatment was performed. Gates Glidden drills were used to retrieve gutta-percha from the canal. All the specimens were randomly divided into four groups based on the final irrigant used. Group 1 (NaOCl with EDTA), group 2 NaOCl+ MTAD, group 3 NaOCl+RF and group 4 NaOCl+PPE. Cementation of glass fiber posts (GFPs) was performed using self-etch dual-cure resin cement. Sectioning was performed using a slow-speed saw from the coronal, middle, and apical third under constant water irrigation. A universal testing machine was used to assess push-out bond strength (PBS) and failure mode was evaluated using a Stereomicroscope at 40x magnification. One-way analysis of variance (ANOVA) and Tukey multiple comparison tests were used for statistical analysis (p=0.05).

RESULTS

Group 4 (2.5% NaOCl+ PPE) displayed the highest PBS at all three root levels (Cervical: 11.22±0.74 MPa, Middle: 8.99±0.97MPa, and Apical: 6.00±0.88 MPa). However, Group 1 (2.5% NaOCl+17% EDTA) demonstrated the lowest EBS (Cervical: 9.25±0.17 MPa, Middle: 7.01±1.84 MPa, and Apical: 4.41±0.17 MPa). Inter-group comparison displayed that PBS to be comparable between group 1 and group 3 (2.5% NaOCl+ Riboflavin) (Cervical: 9.74±0.41 MPa, Middle: 7.44±1.18 MPa, and Apical: 4.21±0.05 MPa) (p > 0.05). Whereas, group 2 (1.3% NaOCl+ MTAD) (Cervical: 9.32±1.36 MPa, Middle: 7.17±1.75 MPa, and Apical: 4.85±0.19 MPa) and group 4 demonstrated comparable values of PBS (p >0.05).

CONCLUSION

Pineapple peel extract and a mixture of Doxycycline citric acid and a detergent when used as a final irrigant demonstrated better bond integrity of GFPs to radicular dentin at all three levels coronal, middle and apical.

Efficacy of antimicrobial photodynamic therapy and Er,Cr:YSGG laser-activated irrigation on dentinal tubule penetration of MTA-based root canal sealer: a confocal microscopy study

BACKGROUND

Antimicrobial photodynamic therapy (aPDT) and laser-activated irrigation (LAI) are adjunctive therapies developed to enhance the effectiveness of root canal disinfection. Sealer penetration into dentinal tubules is significant for preventing re-infection, and the sealer's penetration ability is affected by the chemo-mechanical preparation of the root canal. This study aimed to evaluate the efficacy of aPDT and LAI on dentinal tubule penetration of MTA-based root canal sealer.

METHODS

Forty single-rooted mandibular premolars were divided into four groups (n = 10): control, methylene blue 50 mg/L (MB50), curcumin 500 mg/L (C500), and Er,Cr:YSGG and sodium hypochlorite (LAI). The smear removal efficiency of the groups on intraradicular dentin was evaluated with a scanning electron microscope (SEM). Confocal laser scanning microscopy (CLSM) was performed to determine the depth of penetration of MTA Fillapex into dentinal tubules. Data were analyzed statistically.

RESULTS

The maximum penetration depth of the C500 group was significantly higher than that of the other groups in all three levels of root sections (p<0.05). Regarding mean penetration depth, the highest values were obtained from the C500 group. However, there was no statistically significant difference between the C500 and MB50 groups in the middle and coronal thirds of the root (p>0.05). The LAI group showed the lowest penetrated area percentage in the middle and coronal third of the root (p<0.05). The C500 and LAI groups were more effective in removing the smear layer than the control and MB50 groups.

CONCLUSION

aPDT could enhance the penetration of MTA-based root canal sealer into dentin tubules.

Influence of adjunctive photodynamic therapy (curcumin) on the extrusion bond strength of radicular dentin to contemporary root canal sealers

OBJECTIVE

The aim was to compare Photodynamic therapy (PDT) as an adjunct to NaOCl and EDTA on the extrusion bond strength (EBS) of AH Plus (AH), Sealapex (SA) and MTA Fillapex (MF) root canal sealers.

MATERIALS AND METHOD

Root canal treatment for human teeth (n = 60) using protaper universal system was performed followed by irrigation with NaOCl/ EDTA. Samples were divided (n = 30) based on disinfection technique, NaOCl/EDTA and NaOCl/EDTA with PDT (Curcumin-PS-CP) as an adjunct. Specimens were divided in three subgroups (n = 10) based on sealers used (Gp 1-Na-E-AH, Gp 2-Na-E-PDT-AH, Gp 3-Na-E-SA, Gp 4-Na-E-PDT-SA, Gp 5-Na-E-MF & Gp 6-Na-E-PDT-MF). Canals were dried and obturated followed by sectioning at coronal and middle third. EBS testing was performed using a universal testing machine (UTM) and modes of failure were assessed. Analysis of variance (ANOVA) and Tukey multiple comparison tests were used to compare the means of EBS. (p < 0.05).

RESULTS

Sealers showed a significant influence on EBS, as Gp 1 (Co: 9.21 ± 0.62, Mid: 8.54 ± 0.55) and Gp 2 (Co: 7.11 ± 0.68, Mid: 7.30 ± 0.37) showed higher EBS than Gp 3 (Co: 5.21 ± 0.63, Mid: 4.36 ± 0.83) and Gp 4 (Co: 5.39 ± 0.72, Mid: 4.46 ± 0.74). Gp 5 (Co: 9.04 ± 0.13, Mid: 8.14 ± 0.91) and Gp 6 (Co: 8.67 ± 0.42, Mid: 8.07 ± 0.07) exhibited higher EBS than Gp 3 and Gp 4 specimens. Adjunctive use of PDT for AH sealer (Gp 2) showed decreased EBS compared to Gp 1 specimens. EBS remained comparable for both MTA-Fillapex and Sealapex with and without PDT.

CONCLUSION

AH Plus (Gp 1 and 2) and MTA-Fillapex (Gp 5 and 6) sealers displayed better EBS compared to Sealapex (Group 3 and 4). Adjunctive Application of PDT (CP) did not show a significant improvement in bond strength of sealers to root dentin.

Efficacy of photodynamic therapy, photobiomodulation and antimicrobial agent on the shear bond strength of composite restorations to hypomineralized teeth

PURPOSE

The aim of this study was to investigate the adhesive bond strength and fracture analysis of resin based restorations to carious dentin of hypomineralized molars (HMs) after disinfecting with photodynamic therapy (PDT), Nd:YAG and chlorhexidine (CHX).

MATERIALS AND METHODS

Sixty carious HM molars were investigated. After removal of all carious infected tissue, the cavities were condition with methylene blue initiated PDT, a 1064 nm wavelength Nd:YAG laser or 2.0% CHX gel. Non-carious dentin from HM was used as a control without performing any disinfection or conditioning technique. All samples were bonded using a one-step one-coat adhesive bond over the dentin surface, packed with composite and light cured. All specimens were subjected to thermocycling at 5°C and 60°C with a dwell time of 30 s for 10,000 cycles. Bonded specimens were placed on a universal testing machine with a flat loading head. The debonded surface were viewed under light optical microscope to estimate the type of failure including adhesive, cohesive, and admixed.

RESULTS

The highest mean SBS was seen in the non-carious HM (control group). The mean score for control group was 17.64 ± 2.96 MPa. The lowest bond strength value was displayed for Group-PDT (11.37 ± 3.66 MPa) and Group-Nd:YAG (12.69 ± 2.45 MPa). Affected dentin disinfected with the Group-CHX (15.71 ± 3.04 MPa) bonded with composite showed statistically significantly higher SBS values compared to the laser groups (p < 0.05). No statistically significant difference was noted with specimens disinfected with PDT and Nd:YAG laser showed comparable SBS scores (p > 0.05). Fracture analysis showed equal incidence of adhesive and cohesive failures in control group and Group-CHX. Moreover, a significant number of failures in group-PDT were related to adhesive. Whereas in group 4, admixed type failures were common.

CONCLUSION

Caries infected hypomineralized teeth demonstrated lower bond strength values compared to non-carious hypomineralized teeth. Adhesive bond strength of hypomineralized teeth was highest with chlorhexidine compared to other laser treatment strategies.

Impact of photodynamic therapy on the push-out bond strength of fiber posts to root dentin: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

This systematic review documents the up-to-date evidence on the efficacy of photodynamic therapy (PDT) on the push-out bond strength of fiber posts cemented to root dentin.

MATERIALS AND METHODS

The focused PICO question was: "What impact does PDT have on the push-out bond strength of fiber posts cemented to root dentin?" This systematic review followed the guidelines and recommendations reported in the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines chart. An electronic search was performed in MEDLINE/PubMed, SCOPUS, Web of Science, and Embase from January 1980 up to and including January 2020. Heterogeneity was calculated for push-out bond strength by means of the Chi-square test and I² statistics. For meta-analyses, if the I² was higher than 50 %, a random effects model was used, otherwise a fixed effects model for I² ≤50 % was applied. A p-value <0.05 was set for significant heterogeneity. Forest plots were computed reporting standard mean differences (SMD) of outcomes and 95 % confidence intervals (CI).

RESULTS

In total, ten studies were included, all of wich demonstrated medium risk of bias. All studies tested the push-out bond strength by means of a universal testing machine with applying a load ranging between 0.5 and 1 mm/min speed. Of the 10 studies, nine (90 %) indicated that PDT had no effect on push-out bond strength of fiber posts to root dentin. Only one study indicated that PDT significantly improved the bond strength when compared with other control groups. The overall mean difference for push out bond strength showed no statistically significant difference between PDT and the control group (SMD = -1.11 [-3.25, 1.02], Z=-1.02, p = 0.305).

CONCLUSION

This systematic review concludes that PDT has no effect on improving the push-out bond strength of fiber posts to root dentin.