Activated Irrigation vs. Conventional non-activated Irrigation in Endodontics - A Systematic Review

Antimicrobial efficacy of two commercially available herbal products with and without ultrasonic activation in primary endodontic infections: A randomized clinical trial

Background

Effective irrigation is crucial for successful endodontic treatment. Traditional irrigants like sodium hypochlorite (NaOCl) have been widely used, but there is a growing interest in exploring natural alternatives for their potential antimicrobial properties.

Objective

The study aims to compare the antimicrobial efficacy of Neem, Bitter Gourd, and NaOCl, with and without ultrasonic activation in managing primary endodontic infections.

Materials and Methods

Ninety patients were randomly assigned six groups (n = 15) Group 1: NaOCl, Group 2: NaOCl with passive ultrasonic irrigation (PUI), Group 3: Neem juice, Group 4: Neem juice with PUI, Group 5: Bitter gourd juice, and Group 6: Bitter gourd juice with PUI. Bacteriological samples were collected before (S1) and after (S2) shaping, plated on brain heart infusion agar, and colony counting was done after 24 h.

Statistical Analysis Used

Shapiro-Wilk test, one-way ANOVA, post hoc Tukey analysis, and paired t-test.

Results

All the groups demonstrated a significant reduction in bacterial count. Groups with PUI (2, 4, 6) demonstrated higher mean bacterial reduction than their counterparts without PUI (1, 3, 5).

Conclusion

Neem and Bitter gourd juices, particularly when used with PUI, demonstrated antimicrobial efficacy comparable to NaOCl with PUI.

Assessment of Apical Pressures in Single and Joining Canals - An Ex Vivo Study Based on Computational Fluid Dynamic Analysis

OBJECTIVE

Computational fluid dynamic analysis (CFD) is claimed to be a reliable tool for analysing the fluid flow and the generated apical pressures in the simulated root canal. The current study aimed to analyse the apical pressures in extracted teeth with single and joining canals.

METHODS

Forty-six freshly extracted teeth were collected for the present study. The power was set at 95%, with an effect size of 0.55 (1-β=95%, α=0.05). Once the root canal anatomy was confirmed with cone-beam computed tomography (CBCT), they were divided into two groups: group I: mandibular second premolars with Vertucci type-I (n=23), and group II: maxillary second premolars with Vertucci type-II (n=23). The instrumentation of the specimens was carried out to a 0.04-taper using rotary instruments. A post-instrumentation CBCT was obtained, and computer-aided design models were obtained. The CFD simulations were then con- ducted with simulated 30-gauge side vented needles at 25, 50, and 75% short of the working length (WL).

RESULTS

Group I recorded significantly (p<0.05) higher apical pressures at needle positions 25% short of the WL. However, no significant differences were elicited in the groups at other needle positions.

CONCLUSION

Single canal specimens recorded higher apical pressures at needle positions 25% short of the WL. However, no differences were elicited between single and joining canals at higher needle positions.

In vitro evaluation of three engineered multispecies endodontic biofilms on a dentinal disk substrate

The aim of this study was the development of a complex multispecies endodontic biofilm using Candida albicans, Proteus mirabilis and Pseudomonas aeruginosa on a biofilm of Enterococcus faecalis in a dentinal substrate design. The endodontic pathology is a biofilm-mediated infection, and the aim of root canal therapy is to reduce, as much as possible, the bacterial population. Thus, it is important to develop a laboratory endodontic biofilm to test the effect of new irrigation and obturation techniques on reduction of bacterial count. The culture of Enterococcus faecalis from ATCC 29212 began with aerobic cultivation on blood agar, followed by transfer to Brain Heart Infusion (BHI) broth with 5% sucrose. Incubation occurred in a shaker at 37 °C for 24 h, followed by an additional 24-h static phase. After 10 d, Proteus mirabilis, Pseudomonas aeruginosa, and Candida albicans were introduced sequentially in three distinct groups. Group 1: the order of addition was Candida albicans, Proteus mirabilis, and Pseudomonas aeruginosa; Group 2: the order was Pseudomonas aeruginosa, Candida albicans, and Proteus mirabilis; and Group 3: Proteus mirabilis, Pseudomonas aeruginosa, and Candida albicans. After 16 days, the biofilm was carefully extracted, transferred to sterile BHI, and dissected using a sterile needle technique. Subsequently, an optical density test, bacterial counts, and colony enumeration were performed on various agar plates. Group 2 in which Pseudomonas aeruginosa was added directly after Enterococcus faecalis followed by Candida albicans and Proteus mirabilis showed significantly greater total bacterial count than the other two groups.

Postoperative pain after endodontic treatment of mandibular molars with two different instrumentation techniques: A randomized clinical trial

Background

This study compared postoperative pain after endodontic treatment of mandibular molars with asymptomatic irreversible pulpitis with the RaCe rotary system and the crown-down versus the step-down technique.

Materials and Methods

In this randomized clinical trial, 70 mandibular 1st and 2nd molars with asymptomatic irreversible pulpitis and normal periradicular state were randomly assigned to two groups for single-visit endodontic treatment with RaCe rotary system and the crown-down and the step-down technique (n = 35). Postoperative pain was assessed at 6, 12, 24, 48, 72, and 168 h postoperatively, using a Visual Analog Scale. Data were analyzed using SPSS 17 by repeated measures ANOVA, Chi-square test, independent sample t-test, and lLeast sSignificant Ddifference test. P < 0.05 was considered statistically significant.

Results

The two groups were not significantly different regarding the pain scores at any time point (P > 0.05). Within-group comparisons showed a significant reduction in pain score over time, starting from 12 to 168 h, postoperatively (P < 0.05).

Conclusion

The crown-down and step-down techniques had no significant difference regarding postoperative pain after endodontic treatment of mandibular molars with asymptomatic irreversible pulpitis with the RaCe rotary system.

Endodontic Flare-Ups: An Update

Root canal treatment deals with mechanical and chemical cleaning followed by obturation that promotes healing and repair of periradicular tissues. Flare-ups can occur in between or some days after endodontic therapy leading to unscheduled visit by the patient. This complication is characterized by severe pain and/ or swelling. There is a correlation between number of appointments, intracanal medicament used and flare-ups. However, there is no sure procedure that can avoid this complication. Therefore, this review article has discussed about causes and some procedures to prevent and treat flare-ups.

Mechanical activation with Easy Clean device enhanced organic tissue removal from simulated internal root resorption in a laboratory evaluation

BACKGROUND

Considering the irregular shape of the root canal, removing inflamed pulp and granulation tissue completely from internal resorption cavities during chemomechanical preparation can be challenging. This study aimed to evaluate the effectiveness of passive ultrasonic irrigation (PUI) compared to mechanical activation with Easy Clean in the removal of organic tissue from simulated areas of internal root resorption.

METHODS

The root canals of 72 extracted single-rooted teeth with oval canals were instrumented with Reciproc R25 instruments. After root canal preparations, the specimens were split longitudinally, and semicircular cavities were prepared using a round bur on each half of the roots. Samples obtained from bovine muscle tissue were weighed and adapted into semicircular cavities. The roots were reassembled and joined, and the teeth were divided into six groups (n = 12) according to the irrigation protocol: Sodium hypochlorite (NaOCl) without activation; NaOCl + PUI; NaOCl + Easy Clean; distilled water without activation; distilled water + PUI; and distilled water + Easy Clean. After irrigation protocols, the teeth were disassembled, and the remaining organic tissue was weighed. Data were analyzed by two-way ANOVA and Tukey's post hoc test (p < 0.05).

RESULTS

None of the experimental protocols totally removed the bovine tissue from simulated cavities. Tissue weight reduction was significantly affected by the activation method (p < 0.05) and by irrigation solution (p < 0.05). Groups with NaOCl irrigation presented higher tissue weight loss when compared to distilled water, for all irrigation methods (p < 0.05). The use of Easy Clean resulted in the greatest tissue weight loss (42.0%-Distilled water/45.5%- NaOCl) compared to those of PUI (33.3%-Distilled water/37.7%- NaOCl) and no activation (33.4%-Distilled water/38.8%- NaOCl) (p < 0.05). However, no differences were observed between PUI and no activation groups (p > 0.05).

CONCLUSIONS

Mechanical activation with Easy Clean enhanced organic tissue removal from simulated internal resorption more effectively than PUI. Easy Clean for agitation of the irrigating solution is effective in removing simulated organic tissues from artificial internal resorption cavities, being an alternative to the use of PUI.

Can natural irrigants replace sodium hypochlorite? A systematic review

CONTEXT

Sodium hypochlorite, a gold standard for irrigation in endodontics, has disadvantages like toxicity and root dentin weakening. Alternatives derived from natural products are being explored.

AIMS

This systematic review was done to understand the clinical benefits of natural irrigants when compared with a standard irrigant, sodium hypochlorite.

SETTINGS AND DESIGN REGISTRATION

This systematic review was registered with PROSPERO (2018 CRD42018112837) METHODS AND MATERIAL: This review was done in conformation to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA 2020) statement. In vivo studies using at least one natural irrigant and sodium hypochlorite (NaOCl) were included. Studies using them as medicaments were excluded. PubMed, Cochrane and SCOPUS were searched. RevMan tool for Risk of Bias 2 (RoB 2) and risk-of-bias tool to assess non-randomized studies of interventions (ROBINS-I) were used. GRADEpro was used to assess certainty of evidence.

RESULTS

Ten articles (6 RCTs and 4 clinical studies) on approximately 442 patients were included. Seven natural irrigants were evaluated clinically. Due to the heterogeneity, meta-analysis could not be conducted. Antimicrobial efficacy was found to be similar for castor oil, neem, garlic-lemon, noni, papaine and NaOCl. Neem, papaine-chloramine, neem-NaOCl and neem-CHX were superior, while propolis, miswak and garlic were inferior to NaOCl. Post-operative pain was less for neem. There was no significant difference between papaine-chloramine, garlic extract and sodium hypochlorite in clinical/radiographic success.

CONCLUSIONS

The studied natural irrigants are not more efficacious than NaOCl. At the moment, they cannot replace NaOCl routinely and may only substitute in select cases.

Post-endodontic pain evaluation after different intracanal laser assisted disinfection techniques. A Systematic Review

Background

Post-endodontic pain (PEP) management is an important factor to be considered in endodontic treatment. Several risk factors have been described that can attribute to its appearance. Laser-assisted disinfection has been described by many authors for its antimicrobial effect. Few studies described the relation between laser disinfection and its effect on PEP. The objective of this review is to describe the relation between different intracanal laser disinfection techniques and their effects on PEP.

Material and Methods

An electronic search strategy was performed in Pubmed, Embase, and Web of Science (WOS) databases without restrictions as to the date of publication. Eligibility criteria were randomized controlled clinical trials (RCT) that used one of the different intracanal laser disinfection techniques in their experimental groups evaluating PEP outcome were included. Risk of bias analysis was performed by the Cochrane risk of bias tool.

Results

The initial research identified 245 articles from which 221 were excluded and 21 studies were sought for retrieval and 12 articles met our inclusion criteria for the final qualitative analysis. The laser systems used were Nd:YAG, Er:YAG and, diode lasers including photodynamic therapy.

Conclusions

The diode lasers showed the most promising results in terms of PEP reduction while Er:YAG showed more short-term efficacy (6 hours postoperative interval). The variables could not be analyzed homogenously due to the differences in the study designs. More RCT are needed comparing different laser disinfection techniques with the same baseline endodontic pathology to establish a specific protocol for the best outcome. Key words:Root canal treatment, Post-endodontic pain, Intracanal laser disinfection, laser dentistry.

To evaluate and compare the effect of 17% EDTA, 10% citric acid, 7% maleic acid on the dentinal tubule penetration depth of bio ceramic root canal sealer using confocal laser scanning microscopy: an in vitro study

Background: The main factors that affect the success of an endodontic infection are effective cleaning and shaping of the root canal system including complete disinfection by using chemical irrigating solutions and obturation with an endodontic sealer to provide a fluid-tight seal. Using rotary and hand instruments for shaping and cleaning the root canal along with irrigants produces a smear layer on the surface of the root dentin affecting the penetration of the endodontic sealer into the dentinal tubules. This smear is difficult to remove with the use of only endodontic irrigants, hence, chelating agents were introduced in adjunct with irrigating solutions for irrigation protocol for effective removal of smear layer which affect the penetration of endodontic sealers into the dentinal tubules. Methods: 32 mandibular premolar teeth were used. The biomechanical preparation was done till Protaper F3 size. Irrigation was done with 2.5 mL sodium hypochlorite (NaOCl) solution after each instrumentation change for 1 min. Samples were then divided into 4 groups according to the irrigating solution used as the final rinse used with passive ultrasonic agitation. The groups were: Group I: 5 ml of saline, Group II: 5ml of 17% ethylenediaminetetraacetic acid, Group III: 5 ml of 10% citric acid, Group IV: 5 ml of 7% maleic acid each for one minute. All the canals were obturated with BioRoot tmRCS with gutta-percha using the ultrasonic condensation technique. For staining the samples for Confocal LASER microscopy, BioRoot tmRCS was mixed with Rhodamine B dye. Results: The maximum penetration of bio-ceramic sealer was observed in the coronal region. At the apical third, the maximum sealer penetration was seen with 7% maleic acid. Conclusions: Maximum sealer penetration was seen in the coronal section followed by the middle and apical section. Maximum sealer penetration was seen with 7 % maleic acid at the apical third.

To evaluate and compare the effect of 17% EDTA, 10% citric acid, 7% maleic acid on the dentinal tubule penetration depth of bio ceramic root canal sealer using confocal laser scanning microscopy: an in vitro study

Background: The main factors that affect the success of an endodontic infection are effective cleaning and shaping of the root canal system including complete disinfection by using chemical irrigating solutions and obturation with an endodontic sealer to provide a fluid-tight seal. Using rotary and hand instruments for shaping and cleaning the root canal along with irrigants produces a smear layer on the surface of root dentin affecting the penetration of the endodontic sealer into the dentinal tubules. This smear is difficult to remove with the use of only endodontic irrigants, hence, chelating agents were introduced in adjunct with irrigating solutions for irrigation protocol for effective removal of smear layer which effect the penetration of endodontic sealers into the dentinal tubules. Methods: 32 mandibular premolar teeth were used. The biomechanical preparation was done till Protaper F3 size. Irrigation was done with 2.5 mL sodium hypochlorite (NaOCl) solution after each instrumentation change for 1 min. Samples were then divided into 4 groups according to the irrigating solution used as the final rinse used with passive ultrasonic agitation. The groups were: Group I: 5 ml of saline, Group II: 5ml of 17% ethylenediaminetetraacetic acid, Group III: 5 ml of 10% citric acid, Group IV: 5 ml of 7% maleic acid each for one minute. All the canals were obturated with BioRoot tmRCS with gutta-percha using the ultrasonic condensation technique. For staining the samples for Confocal LASER microscopy, BioRoot tmRCS was mixed with Rhodamine B dye. Results: The maximum penetration of bio-ceramic sealer was observed in the coronal region. At the apical third, the maximum sealer penetration was seen with 7% maleic acid. Conclusions: Maximum sealer penetration was seen in the coronal section followed by the middle and apical section. Maximum sealer penetration was seen with 7 % maleic acid at the apical third.

The Effectiveness of Different Irrigation Techniques on Debris and Smear Layer Removal in Primary Mandibular Second Molars: An In Vitro Study

AIMS

The aim of the present in vitro study was to compare the effectiveness of passive ultrasonic irrigation (PUI), sonic irrigation, and mechanic dynamic activation on the removal of debris and smear layer from primary mandibular second molars during pulpectomy.

MATERIALS AND METHODS

Mesial roots of 48 primary mandibular second molars were prepared with an R-motion 21 mm file (30/0.04) (FKG Dentaire SA, La Chaux-de-Fonds, Switzerland), irrigated with 1% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetraacetic acid (EDTA), and divided into four groups (n = 24 canals) according to the final irrigation activation technique: control group without activation, PUI with Ultra-X (Eighteeth, Changzhou, China), mechanical activation with XP-endo Finisher (FKG), and sonic irrigation with EQ-S (Meta Biomed, Chungcheongbuk-do, Korea). The roots were split longitudinally and analyzed using scanning electron microscopy (SEM). The presence of debris and smear layer was assessed using a 5-grade scoring scale with 200× and 1000× magnification, respectively. The Kruskal-Wallis and Friedman tests were used for data analysis.

RESULTS

The activation of the irrigant significantly improved debris and smear layer removal (p < 0.001). There was no significant difference between Ultra-X, XP-endo Finisher, and EQ-S (p > 0.05). No activation technique was able to completely eliminate debris and smear layer from the root canals of primary mandibular second molars.

CONCLUSIONS

During pediatric pulpectomy, the irrigation protocol must include activation of the irrigation solutions using either ultrasonic, sonic, or mechanical activation techniques to enhance the removal of debris and smear layer for a better prognosis.

CLINICAL SIGNIFICANCE

During root canal treatment on primary teeth, the clinician must incorporate an activation technique in the irrigation protocol to enhance the removal of debris and smear layer and increase the success of the treatment.

Knowledge, attitude, and practice of ultrasonics in endodontic treatment: A Survey among general practitioners and endodontists

The use of ultrasonics (US) has greatly expanded in the field of dentistry. Over the past few decades, the application of US has increased substantially in endodontics owing to the predictable prognosis and ease of operation. The objective of this survey was to determine the knowledge, practice, and attitude of US in endodontics among the general practitioners, postgraduates, and endodontists. An electronic questionnaire containing 16 questions regarding the knowledge, attitude, and practice of US in endodontics was circulated among the general dentists, postgraduates, and endodontists and the responses were collected online. Data were statistically examined using IBM SPSS software. A total of 202 dentists (general dentists = 92, endodontists = 77, and postgraduates = 33) participated in the survey. Eighty-nine percent of them were aware of the use of US in endodontics, 36.1% of them preferred using US in the removal of pulp chamber calcifications, pulp stones, access refinement, and troughing hidden canals, and 61.4% chose <3% sodium hypochlorite for root canal irrigation with US. The cost of the ultrasonic unit and heat generation during procedures were considered the greatest limitation in using the US. The majority of the dentists were well aware of the use of US and its advantages in various endodontic procedures but they did not use it routinely in their practice. The use of US has been reported to have greatly increased the predictability of endodontic treatment.

Antibacterial effect of nano-chlorhexidine on Enterococcus faecalis biofilm in root canal system: An in vitro study

BACKGROUND

A new method to improve the properties of the materials is nano-encapsulation, which improves the biological properties, antibacterial activity along with reduction of toxicity. Due to the spread of nano-knowledge, the present study was performed to evaluate the antibacterial effect of nano-chlorhexidine (CHX) on Enterococcus faecalis biofilm in the root canal system.

MATERIALS AND METHODS

In this in vitro experimental study, 55 matured single-root mandibular premolars were decoronated and the canals were prepared by single length method up to #F3 ProTaper Universal system. Five teeth were selected as negative control. Then, the teeth were randomly divided into three experimental groups (n = 15) and a positive control group (n = 5). The experimental groups were irrigated with 2% nano- CHX gel, 2% CHX solution, and 5.25% sodium hypochlorite (NaOCl), respectively. Finally, the number of colonies was counted. Kruskal-Wallis test was used to compare the number of colonies among groups. The level of significance was set at P < 0.05.

RESULTS

The mean number of colonies in the groups of nano-CHX, NaOCl, CHX, and positive control were obtained as 17.73 ± 18.69, 35.53 ± 36.42, 38.8 ± 31.8, and 96.8 ± 22.52, respectively. There was a significant decrease in the number of colonies in all the experimental groups compared to the control group (P < 0.05). However, difference in the number of colonies among these three groups was not significant (P > 0.05).

CONCLUSION

The use of nano-CHX in removing E. faecalis biofilm from root canal is as effective as the use of CHX and NaOCl.

Comparative Study Assessing the Canal Cleanliness Using Automated Device and Conventional Syringe Needle for Root Canal Irrigation-An Ex-Vivo Study

The success of endodontic treatment relies on both apical and coronal sealing. To achieve a good three-dimensional seal, the removal of the smear layer becomes mandatory. This study aims to assess the difference in debris accumulation and smear layer formation while using automated root canal irrigation and conventional syringe needle irrigation. Single-rooted human mandibular premolar teeth (n = 30) which were indicated for orthodontic extractions were selected. An endodontic access cavity was prepared, and a glide path was created. Based on the irrigation protocol decided upon for the study, the teeth were randomly allocated into three study groups, namely Group 1, where the manual syringe needle irrigation method was adopted; Group 2, in which automated root canal irrigation was undertaken; and Group 3, in which teeth remained un-instrumented as it was considered the Control group. The teeth were decoronated at the cement-enamel junction (CEJ) and were subjected for scanning electron microscopy (SEM) examination. Debris and smear layers were viewed in 1000× magnification and scored. A statistically significant (p < 0.05) lower mean debris and smear layer score (p < 0.05) was observed in both study groups when compared with the control group. However, no significant difference (p > 0.05) in the debris and smear layer was observed between the manual syringe needle irrigation and automated irrigation, although automated irrigation devices can be a potential alternative. The present study concluded that the efficacy of smear layer removal remained the same with both automated irrigation and manual syringe irrigation.

Comparison of EASYDO ACTIVATOR, passive ultrasonic, and needle irrigation techniques on the treatment of apical periodontitis: a study in rats

OBJECTIVES

To evaluate the long-term therapeutic effect of EASYDO ACTIVATOR, passive ultrasonic irrigation, and needle irrigation in experimental apical periodontitis in rats.

MATERIALS AND METHODS

Sprague-Dawley male rats were used to produce periapical lesions. The pulp chambers of the bilaterally first mandibular molars were exposed and left open for 21 days. The rats were divided into four groups according to different irrigation protocols. Seven days after irrigation, the mandibles were removed for micro-CT, histological, and immunohistochemical analysis. Serum levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were assessed by enzyme-linked immunosorbent assays (ELISA). Statistical data were analyzed by one-way analysis of variance (ANOVA) with LSD tests.

RESULTS

The passive ultrasonic irrigation and EASYDO ACTIVATOR groups had the smallest apical lesions compared to the other groups (P < 0.05), while the needle irrigation group had smaller lesions than the control group (P < 0.05). The EASYDO ACTIVATOR group had less inflammation infiltration compared to the control and needle irrigation groups (P < 0.05). The control and needle irrigation groups had more TNF-α expression compared to the passive ultrasonic irrigation and EASYDO ACTIVATOR groups (P < 0.05). The lowest IL-6 expression was observed in the EASYDO ACTIVATOR group. The EASYDO ACTIVATOR group had the lowest serum level of TNF-α than other groups (P < 0.05). IL-6 expression was significantly lower in the EASYDO ACTIVATOR group in comparison with the control and needle irrigation groups (P < 0.05).

CONCLUSIONS

EASYDO ACTIVATOR can significantly reduce the apical lesions and decrease the inflammatory response around the periapical area.

CLINICAL RELEVANCE

EASYDO ACTIVATOR is recommended for clinical application.

Does ultrasonic activation of irrigation during endodontic therapy improve the clinical and microbiological effects?

Data sources A comprehensive collection of databases were searched from inception to August 2020, such as Cochrane, MEDLINE, Scopus and Web of science. Also, references and citations of retrieved records, conference proceedings and leading journals were searched.Study selection All randomised clinical trials on root-canal-treated adult permanent teeth that compared the outcomes of ultrasonically activated irrigation (UAI) to syringe irrigation (SI) were eligible. The outcomes considered were post-operative pain, pain intensity, periapical healing after 12 months, the incidence of microbial presence, microbial quantification, lipopolysaccharides (LPS) quantification and lipoteichoic acid quantification. Studies with insufficient data for risk of bias assessment or other outcomes were excluded.Data extraction and synthesis The two independent reviewers did the screening process in title, abstract and full-text assessment steps. Also, the data extraction process and risk of bias assessment were done by two independent reviewers. Any disagreement was resolved by consensus or the opinion of a third reviewer. Any missing information was filled in by contacting the authors. The Cochrane risk-of-bias tool for randomised trials was used to assess the risk of bias. The following domains were evaluated for risk of bias: randomisation process, deviation from the intended interventions, missing outcome data, outcome measurement and the selection of the reported results. If all domains were rated as 'low risk', judgements would be rated as 'low risk', otherwise, 'high risk'. The risk ratios and mean risk difference with 95% confidence interval (CI) were used as measure effect. The random effects model was used to combine the effects. The heterogeneity is measured by I² test (I² test >50% and p <0.1 considered as substantial heterogeneity). The level of certainty of evidence for clinically important outcomes was determined using the guidelines of Grading of Recommendations Assessment, Development and Evaluation working group.Results Four studies entered the meta-analysis stage based on pain outcomes. The overall risk of bias for three of them was assessed as high. All of them had examined pain incidence before 24 hours but only two studies have examined the occurrence of pain in the period of 24-72 hours and after 72 hours to 7 days. Considerable heterogeny was among the incidence of pain <24 hours between studies (I²= 83%). Therefore, the incidence of pain in two sub-groups of vital and non-vital pulp has been investigated. In the non-vital pulps, the incidence of pain by UAI was half of the incidence of SI pain (relative risk= 0.50; 95% CI 0.35-0.71; I2 = 0%; 308 teeth). But no significant difference was seen in vital pulps. Also, there was no significant difference in the occurrence of pain after 72 hours between the two methods. Two studies assessed the intensity of pain in three periods: <24 hours, 72-24 hours, more than 72 hours and less than 7 days. The combined results based on vital and non-vital groups resulted in no significant difference in any period. Pooled data of pain outcomes were assessed with very low or low confidence of evidence.Five studies with microbiology-related outcomes entered the final analysis stage. The overall risk of bias for two of them was high. Three studies evaluated the effect of the irrigation method on microbial presence as an outcome. High heterogeneity was among the results of the studies (I²= 72%). However, with and without subgroup analysis, meta-analysis results showed no significant difference between these two methods. A lower microbial count was found with UAI than SI in a meta-analysis of four studies (standardised mean difference-pooled - 0.40; 95% CI [-0.78, -0.02]; I2 = 0%; 126 teeth). Two studies measured LPs. The meta-analysis showed lower values of LPS with UAI compared to SI (34, 37) (mean difference pooled - 0.06; 95% CI [-0.11, -0.01]; 61 root canals; I² = 29%). One study measured lipoteichoic acid and found no significant difference between the irrigation methods.Three studies with treatment-success-related outcomes entered the meta-analysis stage with an overall high risk of bias. Two studies' pooled data revealed no significant difference between the irrigation methods regarding treatment failure. One study assessed periapical-lesion volume after treatment and found no significant difference between the irrigation methods.Conclusions According to limited data, UAI may reduce the risk of post-operative pain during the first 24 hours and reduce microbial counts, particularly cultivable germs in cases of apical periodontitis. However, most meta-analyses are conducted on a small number of studies and have an overall 'very low' to 'low' certainty of evidence; as a result, the evidence is deemed insufficient to either support or disprove UAI efficacy when compared to SI.

Post-Operative Endodontic Pain Management: An Overview of Systematic Reviews on Post-Operatively Administered Oral Medications and Integrated Evidence-Based Clinical Recommendations

Endodontic treatment comprises the overall management of pre-, intra- and post-operative symptoms, including post-operative endodontic pain, considered as a complication susceptible of chronicization. Post-operative pain is very common and highly unpreventable and has a multi-factorial etiology and a potential pathogenic link to the acute inflammation of the periapical area, secondary to localized chemical, mechanical, host and/or microbial damage occurring during endodontic treatment. Considering the multitude of heterogeneous technical and pharmacological approaches proposed to control post-operative endodontic pain, the present study primarily comprised an overview of systematic reviews of systematic reviews of randomized clinical trials, summarizing findings on post-operatively administered oral medications for post-operative endodontic pain control, in order to note the most effective type and dosage of such drugs. Secondarily, a narrative review of the current evidence on technical solutions to be observed during endodontic treatment procedures, to control post-operative pain, was conducted to provide integrated evidence-based clinical recommendations for optimal post-operative endodontic pain management.

Irrigating Solutions and Activation Methods Used in Clinical Endodontics: A Systematic Review

Background

Ex vivo and in vitro studies have demonstrated the effectiveness of some irrigation protocols in reducing the bacterial load in the root canal system. However, standardized protocols have not yet been defined for the real clinical context due to many irrigation procedures available.

Objective

To evaluate the clinical endodontic protocols and limitations of irrigating solutions in the disinfection of the root canal system in patients with apical periodontitis.

Methods

PubMed, Scopus, Embase, Web of Science, and Cochrane databases were searched for randomized controlled trials (RCT) published until January 2021. Hand searching was also performed. Studies focused on evaluating the effectiveness of irrigating solutions and/or irrigation activation methods in reducing the bacterial load in the root canal system were considered. The Cochrane risk-of-bias tool for randomized trials (RoB2) was used to assess the quality of the studies.

Results

Four hundred and twenty eight published articles were identified. After removing the duplicate studies and analyzing full texts, seven RCTs were selected. Two studies compared pure NaOCl with some combination of NaOCl with HEDP and MTAD. Two studies analyzed the antibacterial efficacy of NaOCl and chlorhexidine (CHX). Three studies compared conventional needle irrigation with different irrigation activation methods (PUI, XP-endo finisher, F-file activator, EndoVac activator). The review attained a satisfactory methodology. The main results of each included study were described.

Discussion

Activation methods provide significantly higher biofilm reduction than conventional needle irrigation methods. Combinations of NaOCl with different chelating agents were ineffective in terms of antimicrobial, but it could potentially increase the risk of irrigant extrusion. However, the irrigating protocols were not carefully detailed, especially those regarding the irrigants application time or total volume. The existing literature lacks high-quality studies. The level of evidence is moderate.

Conclusions

The available data is too heterogeneous to compare and identify the superiority of specific valuable irrigation protocols in each clinical context. Application time, volume, and activation methods should be standardized to determine the optimal irrigating procedures to reduce the bacterial load and ensure higher predictability of the endodontic treatment.

Systematic Review Registration

(https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=218555), PROSPERO registration: CRD42020218555.

Effect of Chemical Debridement and Irrigant Activation on Endodontic Treatment Outcomes: An Updated Overview

Chemical debridement is considered one of the most important steps during root canal treatment to target unreached areas and provide thorough disinfection of the canals. The efficiency of this step efficiency can be increased using different agitation and irrigation techniques/devices. This comprehensive review aimed to summarize the effect of various irrigant activation and agitation techniques/devices on endodontic treatment outcomes. Using mechanical active irrigation, which enables the activation or agitation of the irrigating solution, is beneficial in root canal treatment by increasing the efficiency of delivering the irrigant up to working length and ensuring isthmus cleanliness. However, considerable variation was noticed between the protocols used in each technique with a lack of well-designed randomized clinical trials to focus on the long-term outcome. Moreover, a low level of evidence was noticed regarding the effectiveness of certain activation techniques over others. Therefore, each study needs to be carefully weighed before using its results and embracing its conclusion. Future studies need to focus more on the antimicrobial effect of each technique and its effect on the healing of apical periodontitis. Also, recent advances, such as multisonic and laser activation, are promising tools that need more clinical investigations to show their efficiency.

Endodontic postoperative flare-up: An update

Endodontic treatment corresponds to a combined chemical and mechanical approach, followed by a three dimensional hermetic obturation, that eliminate the pulpal and periradiculare disease and boost healing and repair of periradiculare tissue. Despite the advances in the endodontic field, the inter-appointment flare up remains a true nightmare that encounters every dentist. This complication commences a few hours or days after root canal procedures and it is characterized by the development of pain and/or swelling, requiring an unscheduled appointment for emergency treatment. Different studies showed that flare-ups represent a multifactorial phenomenon including mechanical, chemical and microbial factors. In addition, a correlation was found between flare-up and age, gender, tooth type, presence of preoperative pain, tooth condition before treatment, irrigation techniques, number of visits as well as intracanal medication. Moreover, some medicine intake was proved to be efficient in controlling this postoperative pain. However, a clear procedure to avoid its occurrence is yet to be established. In this review, we summarize knowledge about the etiology of flare-up and its related factors. This could be effective in helping dentists to adapt some strategies to prevent it.

Removal of accumulated hard tissue debris from mesial root of mandibular molars evaluated using micro-CT - a systematic review and network meta-analysis

Aim The aim of this systematic review and network meta-analysis was to identify the best irrigant activation technique (IAT) for the removal of accumulated hard tissue debris (AHTD) from the mesial root of mandibular molars evaluated using micro-CT studies.Methods The research question was based on the PICO format. Four electronic databases - PubMed, Scopus, Embase and Web of Science - were searched for articles up to June 2020. Selected articles were assessed for bias using the Joanna Briggs Institute Critical appraisal tool. The network meta-analysis using a fixed-effects model and SUCRA ranking were performed. The quality of the evidence was assessed using the CINeMA framework.Results Eleven studies were included for qualitative synthesis while seven were included for quantitative synthesis. The risk of bias of all included articles was low. The results based on SUCRA values revealed the IAT shock wave-enhanced emission photoacoustic streaming (100%) resulted in the greatest reduction of the volume of AHTD from mesial roots of mandibular molars. Ranking of the other IATs was as follows: photon-induced photoacoustic streaming (87%), laser-activated irrigation (79.3%), XP EndoFinisher (71.2%), ultrasonically activated irrigation (59.6%), apical negative pressure (42.3%), EasyClean (37.4%), EDDY (26.2%), EndoActivator (24.2%), self-adjusting file (11.6%) and needle irrigation (11.3%).Conclusion None of the IATs rendered the root canals completely free of AHTD. The laser-activated irrigation groups fared better than all other interventions in reducing AHTD from the mesial roots of mandibular molars. The confidence rating ranged from low to high for indirect evidence and moderate to high for mixed evidence. Results must be interpreted with caution due to the laboratory nature of the included studies.

Protocols for Mechanical Cleaning of the Post Space on the Bond Strength Between Root Dentin and Cementation System

OBJECTIVE

To evaluate the effects of mechanical versus chemical cleaning protocols for cleaning the root dentin surface before cementation of fiberglass posts for their effect on the bond strength, failure mode, and dentinal penetration of the cementing agent using an etch-and-rinse adhesive system on dentin prepared to receive a fiberglass post.

METHODS

Forty roots of bovine teeth were endodontically treated and prepared for fiber post cementation. The specimens were randomized into 4 groups of 10: Control group (CO) - irrigation with 2.5% NaOCl; DW group- irrigation with distilled water; RB group - rotating brush for cleaning root canals, and CUI group - continuous ultrasonic irrigation. The fiberglass posts were cemented, and the specimens were immersed in distilled water for 6 months. A push-out test was performed on the cervical, middle, and apical thirds of the samples. Dentinal penetration of the cementing agent and the fracture pattern were evaluated by laser confocal microscopy. Statistical analysis was performed using analysis of variance (ANOVA) and post hoc Tukey tests (α=0.05). Results: The RB and CUI groups showed significantly higher bond strength values when compared to the Control and DW groups (p<0.05). In addition, in the control and DW groups, the apical third presented lower bond strength values when compared to middle and cervical thirds.

CONCLUSION

While DW showed the highest incidence of adhesive type failure, CUI resulted in the highest dentinal penetration of the cementing agent (p<0.05). RB and CUI resulted in the highest bond strength between cementation system and root dentin. In addition, CUI favored greater dentinal penetration of fiberglass post cementing agent.

Comparison of Antibacterial Effects of Photodynamic Therapy and an Irrigation Activation System on Root Canals Infected With Enterococcus faecalis: An In Vitro Study

Introduction: Enterococcus faecalis is a resistant bacterium which is the most abundant species in infected root canals. Photodynamic therapy (PDT) is a method for killing the bacteria with active Oxygen radicals generated in a photosensitizer when exposed to centralized light. Furthermore, as a new method of canal disinfection, a variety of irrigation activation systems have been introduced, one of which is GentleFile (GF) with rotary movements and spiral effects for antibacterial action. This study aimed to compare the effectiveness of the two mentioned methods when used with and without Sodium Hypochlorite in eliminating E. faecalis from infected root canals. Methods: Fifty-eight uniradicular teeth were randomly divided into 4 experimental groups of 14. Two specimens were selected for later scanning electron microscopy in order to screen the procedure steps. In each experimental group, 10 samples were selected to be treated with GF or PDT; 3 of them were selected as positive controls and the other one sample was chosen as a negative control. Experimental groups were as follows: (1) Irrigation activation system, (2) Irrigation activation system + sodium hypochlorite, (3) PDT, and (4) PDT+ sodium hypochlorite. The specimens were then cultured for a bacterial colony count. Results: The decrease in the bacterial count after the treatment with the irrigation activation system was 99.8% (P =0.011) and when the system was used with sodium hypochlorite, it was 100% (P =0.001). The antibacterial effect of PDT was 90.08% (P =0.011) and it was 99.7% when PDT was combined with sodium hypochlorite (P =0.011). Conclusion: All four methods can be administered as complementary methods in root canal disinfection. According to the results of disinfection in the experimental groups of current study it is concluded that integration of new technologies such as activation irrigation system or PDT in Combination with NaOCl ameliorates disinfection of root canal and can provide several advantages in the endodontic outcome.

Current Trends in the Use of Irrigant Activation Techniques Among Endodontists & Post-Graduate Dental Students in India -A Knowledge, Attitude and Practice Based Survey

Objective:

The aim of this survey was to examine the practice/use of Irrigant Activation Techniques (IAT) among Endodontists and post-graduate dental students in India.

Methods:

An invitation to participate in this survey was sent by electronic mail to 902 members of Indian Endodontic society. A total of 32 questions were finalized for the survey after validation by five endodontic experts. Survey contained 2 demographic questions, 7 knowledge based questions, 11 questions on attitude and 12 questions on practice of IAT. The reliability was checked by randomly asking 10 participants to fill the survey forms again after 15 days. The data was analyzed using chi-square test (P<0.05).

Results:

The overall response rate for the survey was 30.5%. The content validity ratio for the questionnaire was 0.972 & the reliability calculated using Kappa scores was 0.978. Most of the respondents (87.3%) use IAT, while 4.7% do not use IAT. Most commonly used IAT was Manual dynamic agitation (MDA) used by 28.7%, followed by Ultrasonics in 17.2%. Sonic & negative pressure (EndoVac) was used by less than 10% of respondents. Combination of IAT was used by 39%. In 23 (5 on knowledge, 9 on attitude & 9 on practice) out of the 32 questions in this survey, there was a statistically significant difference (P<0.05) in the answers between the groups, with post-graduate dental students opting the correct choices. Sodium hypochlorite (NaOCl) is the preferred choice of irrigant for IAT according to 48.6%, Chlorhexidine (CHX) is used by 4.2% & Ethylene diamine tetra acetic acid (EDTA) by 2.4%. Combination of two irrigants is used by 28.7% and 6% use all the three irrigants.

Conclusion:

Vast majority of the Endodontist in India use some form of IAT to improve the efficacy of irrigation. MDA is the most commonly used IAT.