Influence of a Passive Sonic Irrigation System on the Elimination of Bacteria from Root Canal Systems: A Clinical Study

Is XP-endo Finisher a better treatment option for its efficacy against intracanal bacteria for post-treatment apical periodontitis cases than EndoActivator?

To investigate the efficacy of the supplementary use of a rotary agitation method [XP-endo Finisher (XPF)] and sonically-activated irrigation [EndoActivator (EA)], using droplet digital PCR (ddPCR) on reducing the bacterial load in previously root canal treated teeth with apical periodontitis. Twenty patients with post-treatment apical periodontitis were allocated into two groups according to the irrigation activation method used: XPF and EA group. Total bacterial loads, as well as the amount of Enterococcus faecalis (E. faecalis) were determined before (S1) and after (S2) chemomechanical preparation, and after final irrigation activation (S3) by means of ddPCR. The bacterial copy numbers were compared between groups using the Friedman test (Nonparametric Repeated Measures ANOVA). When the groups were examined in terms of gender, age, number of root canals, periapical index score, sterility control total bacteria (SCTB), S1- and S2-total bacteria copy number, it was found that there was no statistical difference between the XPF group and the EA group (p > 0.05). Subsequent activation (S3) resulted in a significant microbial reduction in both XPF and EA groups, both of which reduced significantly more bacteria than chemomechanical instrumentation (S2) (p < 0.0001). On the contrary, S3-total bacteria copy number of the EA group was lower than the XPF group (p < 0.0147). There was no statistical difference between the XPF group and the EA group in terms of E. faecalis copy number (p > 0.05). Although both the XPF and the EA optimised the antibacterial efficiency of chemomechanical preparation in previously root canal-treated teeth with apical periodontitis, a lower total bacterial copy number was achieved with the EA application than the XPF application.

Anatomical complexities affecting root canal preparation: a narrative review

A fundamental aspect of the Endodontic field is the knowledge of root canal anatomy. Using a variety of techniques, the internal and external anatomy of teeth have been extensively investigated throughout the past century. Recent improvements in three-dimensional computed tomography have enabled more detailed evaluations of root canal morphology in both clinical and laboratory settings. Essentially, researches have unveiled that the root canal constitutes a complex system, comprising not only the main root canal but also lateral components, including isthmuses, fins, accessory canals and apical ramifications. Undoubtedly, this intricate morphology poses a significant challenge when it comes to the process of shaping, cleaning and disinfecting the root canal system. This article aims to explore the anatomical aspects of the root canal system that impact the chemomechanical procedures.

Effect of photon-induced photoacoustic streaming and shock-wave enhanced emission photoacoustic streaming technique on the removal of the smear layer after root canal preparation in curved root canals

Background/purpose

The efficiency of root canal irrigation has an important impact on the prognosis of root canal treatment. Photon-induced photoacoustic streaming (PIPS) and shock wave enhanced emission photoacoustic streaming (SWEEPS) are the special modality of Er: YAG laser, whether can they improve the efficiency of root canal irrigation remains to be studied.

Materials and methods

Fifty human teeth with curved root canals were collected and stored in the thymol solution until used in the study. After traditional endodontic cavities preparation, root canals were prepared to size #35 with a 0.04 taper. The final irrigating techniques were as follows: (I) manual dynamic activation (MDA), (II) ultrasonically activated irrigation (UAI), (III) sonically activated irrigation (SAI), (IV) PIPS, and (V) SWEEPS. Fifty teeth were randomly divided into five groups mentioned above. After root canal preparation, the roots were cleaved longitudinally. The dentine surfaces were photographed from the coronal, middle, and apical third of the root by scanning electron microscopy operated at a low vacuum. Two examiners separately graded each image according to the remained smear layer situations.

Results

PIPS and SWEEPS groups showed fewer smear layers remaining than the others in the middle and the apical third (P < 0.05) of the root canal. In contrast, in the coronal third, five groups showed no significant difference (P > 0.05).

Conclusion

PIPS and SWEEPS showed superior smear layer clearing efficiency than traditional irrigating techniques in curved root canals.

Effectiveness of various irrigant activation techniques on the penetration of sodium hypochlorite into lateral canals of mature permanent teeth: A systematic review and meta-analysis

Objective

This review aimed to systematically review the effectiveness of various irrigant activation techniques (IATs) on the penetration of sodium hypochlorite (NaOCl) into the lateral canals of mature permanent teeth.

Methods

Electronic databases including MEDLINE (via PubMed), Scopus, ProQuest, and Cochrane Library were searched to identify laboratory studies evaluating the penetration of NaOCl into lateral canals following the use of apical negative pressure irrigation (ANP), passive ultrasonic irrigation (PUI), sonic irrigation (SI), and/or manual dynamic activation (MDA) techniques. Meta-analysis was performed for individual IATs in comparison with CNI into the lateral canals of both straight and curved root canals. On the basis of the previous literature and parameters, the risk of bias of the selected studies was evaluated with the help of a customized tool.

Results

Of the 983 records screened, 12 studies were selected to include in the systematic review, and 10 studies were selected for the meta-analysis. The total quality assessment across the included studies indicated a high quality (83.3%). Overall, the meta-analysis demonstrated IATs had significant improvement in the penetration of NaOCl into the lateral canals of straight canals (34.3%) over CNI. The subgroup analysis of individual IATs demonstrated PUI (60.9%) to be superior in the penetration into lateral canals of straight canals.

Conclusions

IATs improved the irrigant penetration into lateral canals and therefore their use during routine endodontic practice is recommended. In straight canals, PUI is the most effective IAT followed by ANP, SI, and MDA techniques.

Analysis of the Importance of the Motion Used in the Resistance of Different Mechanical Instrumentation Systems in Endodontics: A Comparative Study

Aim: The aim of this study was to compare the cyclic fatigue strength of different reciprocating rotary systems depending on the movement used. Methods: Four study groups were analyzed (n = 30): (1) Reciproc®, (2) Reciproc Blue®, (3) Wave One Gold® and (4) Procodile®. Each group was divided into three subgroups according to the motion used: (A) Reflex Dynamic® (n = 10), (B) ReFlex Smart® (n = 10) and (C) conventional reciprocating motion (n = 10). They were used in a dynamic cyclic fatigue prototype until their fracture, and the time was measured in seconds. The results obtained were analyzed with the ANOVA method, and for two-to-two comparisons, the Tukey method and Weibull statistics were used. Results: Procodile ReFlex Smart had the longest time to failure, and statistically significant differences were found between Procodile ReFlex Smart and the other files and motions (p < 0.05). Conclusion: Smart motions increase cyclic fatigue strength. ReFlex Smart® motion increases the cyclic fatigue strength of reciprocating rotary systems, and Procodile® ReFlex Smart was the most resistant system file.

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.

Dens invaginatus: clinical implications and antimicrobial endodontic treatment considerations

Dens invaginatus or dens in dente is a developmental dental anomaly resulting from an invagination of the enamel organ into the dental papilla during odontogenesis. Radiographically, it is usually seen as a radiolucent invagination surrounded by a radiopaque area (enamel) limited to the tooth crown or extending into the root. Because the invagination is opened to the oral cavity, it can retain saliva, food remnants, and bacteria. In conditions that the enamel lining of the invagination is naturally absent or lost due to caries, bacterial cells and products can diffuse from the invagination through the dentin tubules to reach the pulp and cause disease. Management of teeth with dens invaginatus include preventive sealing or filling of the invagination, or, if the pulp is affected, therapeutical options include vital pulp therapy, nonsurgical root canal treatment, apexification or regenerative endodontic procedures, periradicular surgery, intentional replantation, or extraction. It is recommended that the invagination be always approached, regardless of the type of dens invaginatus. The root canal should be treated whenever the pulp is irreversibly inflamed or necrotic. Endodontic management of teeth with dens invaginatus is often tricky because of its anatomical complexity, and special and customized strategies should be devised. This review discusses the endodontic implications of this anomaly and the current treatment recommendations based on anatomic, pathologic, and technologic considerations.

Effect of Irrigants and Irrigating Devices on Disinfection of Root Canal System: A Systematic Review

Aim:

The effective delivery of irrigants into the inaccessible areas of the root canal system is the prerequisite for a proper disinfection of the root canal system. Numerous activation devices that can provide effective delivery of the irrigant and aid in the success of the root canal treatment are available. The activation of irrigants has claimed to be effective in in vitro and clinical trials. Hence, the present systematic review aims to analyze the effect of irrigants and irrigating devices in disinfecting the root canal system.

Materials and Methods:

A literature search was undertaken in PubMed, Cochrane, Web of Science, and Scopus databases. The inclusion criteria included clinical trials, both in vivo and ex vivo. The exclusion criteria included animal studies, textbooks, review articles, and case reports. The patients who required endodontic treatment along with the activation of irrigants were chosen as participants for the review.

Result:

The search strategy screened around 132 articles, out of which only 10 were selected for the present systematic review. The risk of bias was calculated based on the following scores: 3, high; 2, moderate; and 1, low. In the present systematic review, four articles were categorized into low-risk bias, three articles were classified as moderate risk, and three articles belonged to the high-risk category.

Conclusion:

The present systematic review concluded that the use of a mechanical activation device along with the irrigant will help in better removal of the smear layer and debris from the root canal system, improving the cleanliness and helping achieve more successful endodontic treatment.

Quaternary ammonium silane (k21) based intracanal medicament triggers biofilm destruction

BACKGROUND

Compare antimicrobial efficacy of a quarternary ammonium silane (QAS)/k21 as an intracanal medicament against E. faecalis and C. albicans biofilms formed on root dentin.

METHODOLOGY

Dentin blocks were sterilized and E. faecalis and C. albicans microbial colonies were counted for colony-forming-units against 2%k21, 2%CHX and Ca(OH)2 medicaments. Biofilm colonies after 7 days on dentin were analysed using confocal laser scanning microscopy with live/dead bacterial viability staining. TEM was done to study dentin collagen matrix. Dentin discs from 3rd day and 7th day well plate was used for Raman spectra and observed under fluorescent-microscope. Docking studies were carried out on MMP-2 S1 binding-domain with k21.

RESULTS

There was reduction of E. faecalis/C. albicans when k21, chlorhexidine and calcium hydroxide were used with highest percentage in 2%k21 treated specimens. 2%k21 showed dense and regular collagen network with intact cross-banding and decreased Raman intensity for 2%k21 on 3rd day. NaOCl + k21 showed least adherence, whereas saline groups showed highest adherence of E. faecalis and C. albicans to root-canal dentin. Alizarin red staining of hDPSCs revealed calcium deposition in all groups with significant difference seen amongst 2%k21 groups. MMP-2 ligand binding was seen accurately indicating possible target sites for k21 intervention.

CONCLUSION

2%k21 can be considered as alternative intracanal medicament.

Clinical efficacy of activated irrigation in endodontics: a focused review

Root canal debridement, which includes the removal of infected tissues and microbial biofilms, is considered the corner stone of root canal treatment. Chemical adjuncts play a multitude of functions in this regard, as tissue solvents, antimicrobial agents and for removing the smear layer. These adjuncts (irrigants) are usually delivered using a syringe and needle. With increasing knowledge of the complexity of root canal anatomy and tenacity of microbial biofilms, the need for strategies that potentiate the action of these irrigants within the root canal system cannot be overemphasized. Several such activated irrigation strategies exist. The aim of this review is to comprehensively discuss the different irrigant activation methods from the context of clinical studies.

The Effectiveness of Three Irrigation Systems in the Enterococcus faecalis Reduction after Instrumentation with a Reciprocating Instrument

OBJECTIVE

 This study aimed to analyze the effectiveness of three irrigation systems: EndoActivator, passive ultrasonic irrigation (PUI), and Easy Clean in the reduction of Enterococcus faecalis, after instrumentation with the reciprocating system, through microbiological collection and culture method.

MATERIALS AND METHODS

 A total of 60 extracted human lower premolars were used and standardized at 16 mm in length. The teeth were accessed, contaminated with E. faecalis, and incubated for 21 days at 37°C. Initial collections (S1) were made with an absorbent paper cone to confirm the contamination; subsequently, instrumentation was performed with WaveOne Primary. The teeth were divided into four groups according to the final irrigation protocol (n = 15): group 1. EndoActivator; group 2, PUI; group 3, Easy Clean; and group 4, control group irrigated with saline solution sterile and without agitation. In the final irrigation, the agitation of the 17% ethylene amine tetra-acetic acid (EDTA) solutions was used, then 2.5% sodium hypochlorite (NaOCl); in both for this, three cycles of 20 seconds each. After the chemical-mechanical preparation and agitation of the irrigating solutions, the final collections (S2) for counting the colony-forming units (CFU/mL) occurred.

RESULTS

 The Kruskal-Wallis test revealed that all the agitation systems reduced by 100% and the control group by 65.7%.

CONCLUSION

 The control group presented a significantly higher amount of CFU/mL after the chemical-mechanical preparation than the other groups, which were similar to each other (p > 0.05).

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

Objective:

Irrigant activation has been claimed to be beneficial in in vitro and clinical studies. This systematic review aims to investigate the clinical efficiency of mechanically activated irrigants and conventional irrigation.

Methods:

A literature search (PROSPERO registration number: CRD42018112595) was undertaken in PubMed, Cochrane and hand search. The inclusion criteria were clinical trials, in vivo/ex vivo on adult permanent teeth involving an active irrigation device and a control group of conventional irrigation. The exclusion criteria were studies done in vitro, animals and foreign language. Adult patients requiring endodontic treatment of permanent dentition and irrigant activation during the treatment were chosen as the participants and intervention respectively.

Results:

After removal of duplicates, 89 articles were obtained, and 72 were excluded as they did not meet the selection criteria. 6 devices (EndoVac, EndoActivator, Ultrasonic, MDA (manual dynamic agitation), CUI (Continuous Ultrasonic Irrigation) and PUI (Passive Ultrasonic Irrigation)) and 6 variables of interest (Post-operative pain, periapical healing, antibacterial efficacy, canal and/or isthmus cleanliness, debridement efficacy and delivery up to working length) were evaluated in the 17 included articles. The risk of bias and quality of the selected articles were moderate. Results showed that mechanical active irrigation reduces post-operative pain. It improved debridement, canal/isthmus cleanliness. It also improved delivery of irrigant up to working length. Bacterial count was more with active irrigation, though not significant. There is no effect on long-term periapical healing.

Conclusion:

It may be concluded that mechanical active irrigation devices are beneficial in reducing post-operative pain and improving canal and isthmus cleanliness during Endodontics.

Distribution of sodium hypochlorite throughout the mesial root canal system of mandibular molars after adjunctive irrigant activation procedures: a micro-computed tomographic study

OBJECTIVES

To evaluate and compare irrigant distribution throughout the root canal system of mesial roots of mandibular molars after application of distinct adjunctive irrigant activation procedures.

MATERIALS AND METHODS

Fifteen extracted mandibular molars presenting Fan's type II, III, or IV isthmus configurations were selected. The canals were initially enlarged and cleaned. The same specimens were subjected to conventional positive pressure irrigation (PPI) followed by adjunctive irrigation approaches: passive ultrasonic irrigation (PUI), mechanical activation with the XP-endo Finisher instrument, and a control group in which the irrigant remained in the canal with no activation. Retention time for the irrigant was the same for all groups. Sodium hypochlorite mixed with a contrast medium (Omnipaque 300) was used as the irrigant. Before and immediately after the adjunctive irrigation, micro-computed tomographic (micro-CT) scans were taken to evaluate the volume of the entire root canal system that was filled by the irrigant. An exclusive analysis was also done for the isthmus area.

RESULTS

Analysis of the entire root canal system showed that the XP-endo Finisher instrument promoted better distribution of the irrigant than PUI and the control group (p < 0.01). PUI was not significantly different from the control group (p > 0.05). A separate analysis of the isthmus area showed no significant difference between the adjunctive irrigation methods and the control (p > 0.05).

CONCLUSIONS

The XP-endo Finisher instrument promoted better distribution of irrigant throughout the root canal system, especially in the apical canal segment, when compared to PUI. However, the tested approaches did not differ as to the ability to drive irrigants into the isthmus area.

CLINICAL RELEVANCE

This study highlighted that the XP-endo Finisher instrument presented a better performance to distribute irrigant throughout the root canal system, especially in the apical canal segment compared to positive pressure irrigation and PUI.

Comparison of bacterial removal from dentinal tubules with different irrigant agitation techniques: An in vitro study

Aim

This investigation was conducted to assess the ability of various irrigant agitation devices to eradicate Enterococcus faecalis from the dentinal tubules of extracted teeth.

Methodology

Fifty roots of extracted human teeth were instrumented to size 30 k with a 0.04 taper. The roots were autoclaved and then injected with E. faecalis. The canals were assigned to one of four intervention groups and disinfected using (A) standard needle irrigation, (B) EndoUltra® Ultrasonic Activator, (C) the EndoActivator system, or (D) EDDY sonic activation and to two control groups that were (E) treated with saline and (F) not inoculated with any bacteria. The roots were split in half, dyed with a LIVE/DEAD Back Light Bacterial Viability Kit, and then scanned with a confocal laser scanning microscope (CLSM) to identify live/dead bacteria in the dentinal tubules.

Results

CLSM images revealed differences among the groups. Both the EndoUltra® Ultrasonic Activator group and the EDDY group had a combination of dead and live bacteria, while the EndoActivator group had mostly dead bacteria, in contrast to single needle irrigation which had mostly live bacteria. Activation of the irrigating solution resulted in more dead bacteria than standard needle irrigation at the coronal, middle, and apical parts of the roots. Overall, the EndoActivator system was superior to all other techniques in reducing live bacteria within the root canal.

Conclusion

Activation of sodium hypochlorite with sonic and ultrasonic systems dramatically reduced live bacteria contamination in the dentinal tubules of infected root canals.

Passive ultrasonic irrigation in root canal: systematic review and meta-analysis

OBJECTIVE

To investigate whether there are differences between the root canal disinfection, comparing the passive ultrasonic irrigation technique with the conventional technique.

MATERIALS AND METHODS

The following electronic databases were searched: Pubmed; VHL; Web of Sciences and OVID with no publication date restriction. The study's quality evaluation was carried out using the Handbook by Cochrane. The online research identified 5464 studies. From the nine studies selected for a full reading of the text, five were included in the present systematic review. Meta-analysis was performed in three articles, which evaluated the root canal's cleanness through microbiological analysis.

RESULTS

Only one article concluded that the ultrasonic passive irrigation showed a better performance compared with the conventional irrigation. None of the articles analyzed presented a low risk of bias in all domains. According to the results of the meta-analysis, there was no statistical difference between the groups (OR = 0.34, IC 95%: 0.10-1.19).

CONCLUSIONS

The level of evidence comparing the two techniques is fragile since in all studies some type of bias was observed which may interfere in the results and conclusions.

Effectiveness of rotary and reciprocating systems on microbial reduction: A systematic review

Introduction:

The role of microorganism and their products in the initiation, propagation, and persistence of periradicular periodontitis has been established. One of the major goals of the treatment of infected root canals of teeth with apical periodontitis is to promote maximal reduction in the intracanal bacterial populations. Engine-driven nickel-titanium instruments possess the latest generation of root canal instruments. The possible benefit of rotary instrumentation over other instrumentation techniques regarding cleaning and disinfecting effects would be irrigant warming and/or turbulence caused by the mechanical rotation of instruments. Furthermore, reciprocating instrument has been introduced for root canal preparation. It has been shown that instruments subjected to reciprocation have increased resistance to fatigue and longer usual life when combined with instruments used in continuous rotation motion. The reciprocating system uses single-file instrumentation technique which can shape and clean the canal in a shorter period and together with the lesser amount of antimicrobial agent.

Objective:

The objective of this study is to compare and evaluate the microbial reduction of rotary and reciprocating systems on microbial reduction.

Search Strategy:

A search was performed in Electronic databases (i.e., PubMed, Cochrane library, Science direct, Lilac, Sigle) using following search terms alone and in combination by means of PubMed search builder from January 1985 to December 2017.

Selection Criteria:

Studies were selected if they met the following criteria: In vivo studies comparing rotary and reciprocating system in asymptomatic apical periodontitis patients.

Main Results:

The results showed that the reciprocating system exerted an almost similar antibacterial effect when compared with the rotary system.

Conclusion:

The present systematic review does not provide concrete evidence to show increased antibacterial efficacy of reciprocating system as compared to the rotary system. Furthermore, clinical trials are required to evaluate the efficacy of various instrumentation systems in reducing bacteria from the root canal system.

In vitro antimicrobial activity of different electrochemically-activated solutions on enterococcus faecalis

Purpose

The aim of this in vitro study was to assess and compare the antimicrobial efficacy of different electrochemically-activated solutions (ECA) and contemporary irrigants, in root canals infected with Enterococcus faecalis, used with or without EndoActivator (EA).

Materials and methods

A hundred single-rooted human teeth were prepared. Ninety of the root segments were infected with E. faecalis for four weeks, and divided into eight test groups (n = 10) (four with and four without EA sonication) and a positive control (n = 10). The irrigants tested were electrochemically-activated solutions produced by the Medilox® (ECA-MX) and Envirolyte® devices (ECA-EN), 2% CHX and 2.5% NaOCl. The root specimens were irrigated with 5 mL of the test solution, with additional sonic agitation applied to the EA groups. The dentine samples that were obtained from the walls were cultured, and the antibacterial efficacy was evaluated by counting the colony-forming units.

Results

The ECA-EN, 2.5% NaOCl and 2% CHX were more effective than the ECA-MX (p<0.05) with the addition of EA sonication, showing no statistical difference in the elimination of E. faecalis.

Conclusion

The ECA-EN shows potential as an endodontic irrigant, while EA usage gives no benefit in reducing bacteria from root canals.

Unprepared root canal surface areas: causes, clinical implications, and therapeutic strategies

Chemomechanical preparation is intended to clean, disinfect, and shape the root canal. This step is of utmost importance during treatment of infected teeth with apical periodontitis, because treatment outcome depends on how effectively the clinician eliminates bacteria, their products, and necrotic tissue that would serve as substrate for bacterial regrowth. Nonetheless, curvatures and complex internal anatomical variations of the root canal system can pose a high degree of difficulty in reaching these goals. In infected teeth, bacteria may persist not only in difficult-to-reach areas such as isthmuses, ramifications, dentinal tubules, and recesses from C-shaped or oval/flattened canals, but also in areas of the main canal wall that remain untouched by instruments. If bacteria withstand chemomechanical procedures, there is an augmented risk for post-treatment apical periodontitis. This article discloses the reasons why some areas remain unprepared by instruments and discusses strategies to circumvent this issue and enhance infection control during endodontic treatment/retreatment of teeth with apical periodontitis.

Treatment of severe periodontic-endodontic combined lesions with minocycline hydrochloride ointment combined with mineral trioxide aggregate

Periodontic-endodontic combined lesions affect the quality of life of patients. The present study aimed to explore a way to achieve maximal effect in treating periodontic-endodontic combined lesions by using a combination of minocycline hydrochloride ointment (MHO) and mineral trioxide aggregate (MTA). In the present study, 294 patients were randomly divided into four groups: Control group, MHO group, MTA group and combination group. Endodontic and periodontic therapy was applied simultaneously on the anterior and posterior teeth of patients, and patient characteristics, gingival index (GI) and probing depth (PD) were noted when the patients were treated with the different strategies. Reexamination was performed 4 weeks after treatment and follow-up was performed 2 years later. The present study demonstrated that medical history, root filling and periapical condition within the patients were deemed as key factors in determining the success of treatment of periodontic-endodontic combined lesions. The effect of the combination treatment significantly exceeded that of either treatment alone (P<0.05). In addition, the teeth were significantly improved for patients with pathological types I, II and III in the combination group compared with either treatment group alone (P<0.05). Furthermore, compared with the MTA and MHO groups alone, the combination group demonstrated a significant decrease in PD and GI in severe periodontic-endodontic combined lesions. In conclusion, the present findings implied that combination treatment is significantly superior to single treatments applied to patients with severe periodontic-endodontic combined lesions.

Effect of ultrasonic agitation on push-out bond strength and adaptation of root-end filling materials

Objectives

This study evaluated the effect of ultrasonic agitation of mineral trioxide aggregate (MTA), calcium silicate-based cement (CSC), and Sealer 26 (S26) on adaptation at the cement/dentin interface and push-out bond strength.

Materials and Methods

Sixty maxillary canines were divided into 6 groups (n = 10): MTA, S26, and CSC, with or without ultrasonic activation (US). After obturation, the apical portions of the teeth were sectioned, and retrograde cavities were prepared and filled with cement by hand condensation. In the US groups, the cement was activated for 60 seconds: 30 seconds in the mesio-distal direction and 30 seconds in the buccal-lingual direction, using a mini Irrisonic insert coupled with the ultrasound transducer. After the materials set, 1.5-mm thick sections were obtained from the apexes. The presence of gaps and the bond between cement and dentin were analyzed using low-vacuum scanning electron microscopy. Push-out bond strength was measured using a universal testing machine.

Results

Ultrasonic agitation increased the interfacial adaptation of the cements. The S26 US group showed a higher adaptation value than MTA (p < 0.05). US improved the push-out bond strength for all the cements (p < 0.05).

Conclusions

The US of retrograde filling cements enhanced the bond to the dentin wall of the root-end filling materials tested.

Effect of a passive sonic irrigation system on elimination of Enterococcus faecalis from root canal systems of primary teeth, using different concentrations of sodium hypochlorite: An in vitro evaluation

Background. This in vitro study aimed to compare the antibacterial effect of different concentrations of sodium hypochlorite on elimination of Enterococcus faecalis from root canal systems of primary teeth with or without a passive sonic irrigation system (EndoActivator).

Methods. The root canals of 120 extracted single-rooted primary incisors were prepared using the crown-down technique. The teeth were autoclaved and inoculated with E. faecalis. The infected samples were then randomly divided into 6 experimental groups of 15 and positive and negative control groups as follows: group 1: 0.5% sodium hypochlorite solution; group 2: 2.5% sodium hypochlorite solution; group 3: 5% sodium hypochlorite solution; group 4: 0.5% sodium hypochlorite solution + sonic activation; group 5: 2.5% sodium hypochlorite solution + sonic activation; and group 6: 5% sodium hypochlorite solution + sonic activation. Microbiological samples were collected before and after disinfection procedures and the colony-forming units were counted. Statistical analyses were performed using the two-way ANOVA and post hoc Duncan's tests in cases of significant difference.

Results. There were no significant differences between the groups in any of the variables (concentration of antiseptic or use of sonic irrigation system).

Conclusion. Use of passive sonic irrigation systems in endodontic treatment of single-rooted primary teeth is of no benefit compared to regular needle irrigation. The results of this study also recommends use of lower concentrations of sodium hypochlorite solution (0.5%) for irrigation of the root canal system rather than higher concentrations given approximately equal efficacy.

Antibacterial Efficacy of a New Sonic Irrigation Device for Root Canal Disinfection

INTRODUCTION

Passive ultrasonic irrigation (PUI) is the most widespread method used to activate irrigation solutions. Concerns have been raised that PUI is less effective in curved root canals and is not passive at all. Our aim was to compare a novel passive sonic irrigation (PSI) device (6000 Hz) with PUI and manual irrigation (MI) with respect to their efficiency in removing different endodontic microorganisms from curved and straight root canals.

METHODS

We performed 2 experiments as follows. In a 3-day infection model, we included 8 groups of single or dual microbial species that were rinsed with 0.9% sodium chloride using PSI, PUI, or MI. Colony-forming units (CFUs) were counted after incubation, and log₁₀ transformations were performed for statistical comparisons. In a 21-d infection model, we tested the same irrigation protocols on 4 groups of microorganisms and used 1.5% sodium hypochlorite as an irrigant. Infection control samples were taken at day 0, 3, 5, and 7 after treatment and were subsequently reincubated.

RESULTS

Using sodium chloride as an irrigant, the amount of reduction in CFUs compared with the negative control was approximately 3 log₁₀ units for PSI at 6000 Hz, 2 log₁₀ units for PUI, and 1 log₁₀ unit for MI. PSI reduced the microorganism CFUs significantly better than PUI. Using sodium hypochlorite led to a significant reduction in microorganism CFUs even with MI. After 3 days, compared with MI, microorganism regrowth significantly reduced after PSI and PUI treatment, but in these groups, in at least half of the samples, microorganisms were detectable after 7 days.

CONCLUSIONS

PSI at 6000 Hz might be at least equal to PUI with respect to reduction of the microbial load in curved and straight root canals.

An analysis in vivo of intracanal bacterial load before and after chemo-mechanical preparation: A comparative analysis of two irrigants and two activation techniques

Background

The goals of this randomized double-blind trial were to assess the antimicrobial activity in vivo of Sodium hypochlorite (NaOCl) vs. chlorhexidine gluconate (CHX) used in combination either with EndoActivator® or IRRI S® files in patients with apical periodontitis.

Material and Methods

A total of 120 patients with apical periodontitis (in single or multiple root canals) were randomly assigned to the four irrigation protocols outlined below: Group A: 5.25% sodium hypochlorite (NaOCl) + EndoActivator®; Group B: 5.25% NaOCl + IRRI S® files; Group C: 2% chlorhexidine gluconate (CHX) + EndoActivator®; Group D: 2% CHX + IRRI S® files. Paper points were used to collect microbiological samples before (1A samples) and after (1B samples) irrigation. Viable colony-forming units (CFU) were quantified twice: (1) without speciation, and (2) only for Enterococcus Faecalis(EF). Statistical analysis was performed using SPSS 22.0 for Windows.

Results

No significant differences were observed between NaOCl and CHX in the reduction of CFU; in fact, reduction was < 93% for the two irrigants. Conversely, statistically significant differences were found between the two activation techniques (sonic and ultrasonic) in the reduction of Enterococcus Faecalis(EF). Thus, the effectiveness of ultrasonic activation was significantly higher (< 93%; p=0.012) as compared to sonic activation. Following the combination of the two irrigants with the two activation techniques (groups A, B, C and D), significant differences were observed between group A and B (p=0.025) in the reduction of EF populations, reaching up to 94%.

Conclusions

NaClO and CHX are effective in reducing intracanal bacterial load. Ultrasonic activation is the most effective activation technique in reducing EF populations.

Key words:Chlorhexidine gluconate, sodium hypochlorite, ultrasonic irrigation, sonic irrigation, apical periodontitis, Enterococcus faecalis.

The efficacy of photon-initiated photoacoustic streaming and sonic-activated irrigation combined with QMiX solution or sodium hypochlorite against intracanal E. faecalis biofilm

The aim of the study was to assess the antibacterial efficacy of photon-initiated photoacoustic streaming (PIPS) using an Er:YAG laser and sonic-activated irrigation combined with QMiX irrigant or sodium hypochlorite against Enterococcus faecalis intracanal biofilm. Root canals of 91 human extracted single-canal teeth were instrumented, sterilized, contaminated with E. faecalis and incubated for 15 days. The infected teeth were then randomly distributed into six experimental groups: G1: PIPS/Er:YAG laser (wavelength 2940 nm, pulse energy 20 mJ, 15 Hz, pulse duration 50 μs, energy density 2.06 J/cm(2), 3 × 20 s) with the QMiX irrigant; G2: PIPS/Er:YAG laser-activated 2.5 % NaOCl; G3 sonic-activated irrigation (EndoActivator system) for 60 s with the QMiX irrigant; G4 sonic-activated irrigation for 60 s with 2.5 % NaOCl; G5 30-gauge needle irrigation with the QMiX irrigant; G6 30-gauge needle irrigation with 2.5 % NaOCl. The positive control group was rinsed with sterile saline solution. The root canals were sampled by flushing with saline solution at baseline and after the treatments, serially diluted and cultured. The number of bacteria in each canal was determined by plate count. The presence and the absence of E. faecalis in root canals were demonstrated by polymerase chain reaction (PCR), and the pattern of the bacteria colonization was visualized by scanning electron microscopy. There was significant reduction in the bacterial population for all groups (p < 0.001). The best antibacterial efficacy was recorded after sonic-activated irrigation with both NaOCl (99.999 %) and QMiX (99.999 %) and after PIPS with QMiX (99.999 %), which were more effective than conventional irrigation with NaOCl (99.998 %) and the PIPS with the NaOCl (99.966 %). Also, the PIPS with QMiX solution provided the highest number of sterile samples (five). There was no difference in the bacteria reduction between the active irrigation techniques, regardless of the irrigant used. Although the laser activation did not improve the antimicrobial action of the NaOCl nor QMiX, the fact that it generated the greatest number of sterile samples warrants further investigation.

Clinical Approach of High Technology Techniques for Control and Elimination of Endodontic Microbiota

The main goal in endodontic treatment is to eradicate or at least reduce intraradicular microbial population to levels that are more compatible with periapical lesions healing process. Since endodontic infections are polymicrobial in nature, intraradicular survival of endodontic microbiota and their pathogenic properties are influenced by a combination of their virulence factors. The purpose of this article is to review the endodontic microbiota and their respective virulence attributes, as well as perform a literature review of the effects of disinfection procedures in the treatment of endodontic infections to gain best practices. Conventional technique for root canal preparation includes mechanical debridement and application of antimicrobial irrigants. Recently, laser irradiation has been used to enhance the results of root canal treatment through its thermal effect. To reduce thermal side effects, laser activated irrigation (LAI) and photon induced photoacoustic streaming (PIPS) were introduced. Antimicrobial photodynamic therapy (aPDT) by photochemical reaction uses light at a specific wavelength to activate a nontoxic photosensitizer (PS) in the presence of oxygen to produce cytotoxic products. Different PSs are used in dentistry including methylene blue (MB), toluidine blue O (TBO), indocyanine green (ICG) and curcumin. Among different options, ICG could be the best choice due to its peak absorption at wavelength of 808 nm, which coincides with the commercial diode laser devices. Also, this wavelength has more penetration depth compared to other wavelengths used in aPDT.

Viability and antibacterial efficacy of four root canal disinfection techniques evaluated using confocal laser scanning microscopy

Background:

Several disinfection techniques have been recently introduced with the main objective of improving root canal disinfection in the inaccessible areas of the root canal system. This in vitro study was done to evaluate the antimicrobial effect and viability of Enterococcus faecalis biofilms using conventional irrigation, EndoActivator (Dentsply, Tulsa Dental, USA), diode laser irradiation and photon-initiated photoacoustic streaming (PIPS).

Materials and Methods:

Root canals of 130 single rooted mandibular premolars, standardized to a uniform length of 20 mm were instrumented until finishing file, F1 (Universal Protaper Rotary System, Dentsply, Tulsa Dental Specialties, USA). After smear layer removal and sterilization, five teeth were randomly selected to assure sterility before bacterial inoculation. The remaining 125 samples were contaminated with E. faecalis suspension, incubated for 21 days and divided into five groups (n = 25). In Group 1; untreated group (positive control), the root canals were not subjected to any disinfection procedure. Sampling was performed within the canals and the colony-forming unit count was evaluated for 20 samples. Five samples were selected to visualize the pattern of colonization at Level 1 (4 mm from the apex) and Level 2 (1 mm from the apex) by confocal laser scanning microscopy. Samples in Groups 2-5 namely conventional needle irrigation, EndoActivator, diode laser and PIPS were subjected to their respective disinfection procedures. Postdisinfection sample evaluation criteria was followed for all groups as same as that for Group 1.

Results:

Diode laser displayed the highest antibacterial efficacy and least viable bacteria than the other three disinfection techniques.

Conclusion:

Diode laser group showed better antibacterial efficacy and least viable bacteria when compared to conventional needle irrigation, PIPS and EndoActivator groups in minimally instrumented, experimentally infected root canals.

Susceptibility of as-yet-uncultivated and difficult-to-culture bacteria to chemomechanical procedures

INTRODUCTION

A significant portion of the bacteria taking part of the microbiome associated with apical periodontitis still remain to be cultivated and phenotypically characterized. This molecular study evaluated the prevalence of selected as-yet-uncultivated and difficult-to-culture bacterial taxa in infected root canals and their susceptibility to chemomechanical procedures.

METHODS

Root canals of single-rooted teeth with apical periodontitis were prepared using rotary nickel-titanium instruments and 2.5% sodium hypochlorite as the irrigant. DNA extracts from samples taken before (S1) and after (S2) chemomechanical preparation were surveyed for the presence of 7 as-yet-uncultivated phylotypes and 1 difficult-to-culture species using end-point polymerase chain reaction. Samples were also subjected to quantitative analysis of total bacteria and levels of the 2 most prevalent taxa.

RESULTS

Bacteroidaceae sp. HOT-272 (24%) and Fretibacterium fastidiosum (20%) were the most prevalent taxa in S1. Their mean counts in S1 were 8.25 × 10(3) and 2.13 × 10(3) rRNA gene copies, corresponding to 0.18% and 0.55% of the total bacteria. Chemomechanical debridement promoted a highly statistically significant reduction in total bacterial counts (P < .001), but 64% of the canals were still positive for bacterial presence. Of the target taxa, only Bacteroidaceae sp. HOT-272 and F. fastidiosum were detected in S2 (each one in 1 sample). The reduction in counts of both taxa was also highly significant (P < .001).

CONCLUSIONS

Findings confirmed that several as-yet-uncultivated and difficult-to-grow bacterial taxa can participate in the microbiome associated with apical periodontitis. Two of them were found in relatively high prevalence but rarely as a dominant species. Chemomechanical procedures were highly effective in completely eliminating these taxa or at least substantially reducing their numbers.

Reduction in bacterial counts in infected root canals after rotary or hand nickel-titanium instrumentation--a clinical study

AIM

To compare the antibacterial efficacy of two instrumentation techniques, one using hand nickel-titanium (NiTi) instruments and the other using rotary NiTi instruments, in root canals of teeth with apical periodontitis.

METHODOLOGY

Root canals from single-rooted teeth were instrumented using either hand NiTi instruments in the alternated rotation motion technique or rotary BioRaCe instruments. The irrigant used in both groups was 2.5% NaOCl. DNA extracts from samples taken before and after instrumentation were subjected to quantitative analysis by real-time polymerase chain reaction (qPCR). Qualitative analysis was also performed using presence/absence data from culture and qPCR assays.

RESULTS

Bacteria were detected in all S1 samples by both methods. In culture analysis, 45% and 35% of the canals were still positive for bacterial presence after hand and rotary NiTi instrumentation, respectively (P > 0.05). Rotary NiTi instrumentation resulted in significantly fewer qPCR-positive cases (60%) than hand NiTi instrumentation (95%) (P = 0.01). Intergroup comparison of quantitative data showed no significant difference between the two techniques.

CONCLUSION

There was no significant difference in bacterial reduction in infected canals after instrumentation using hand or rotary NiTi instruments. In terms of incidence of positive results for bacteria, culture also showed no significant differences between the groups, but the rotary NiTi instrumentation resulted in more negative results in the more sensitive qPCR analysis.

Antimicrobial efficacy of a high-power diode laser, photo-activated disinfection, conventional and sonic activated irrigation during root canal treatment

AIM

To evaluate the antimicrobial effect of a diode laser irradiation, photo-activated disinfection (PAD), conventional and sonic activated irrigation with 2.5% sodium hypochlorite (NaOCl) on Enterococcus faecalis.

METHODOLOGY

Root canals of 120 human extracted teeth with single straight canals were prepared with ProTaper files, sterilized, contaminated with an E. faecalis suspension and incubated for 7 days. They were then randomly distributed into six groups: G1, diode laser irradiation (2 W, 3 × 20 s); G2, PAD (100 mW, 60 s); G3, PAD with 3D Endoprobe (100 mW, 60 s); G4, 30-gauge syringe irrigation with NaOCl (60 s); G5, sonic agitation of NaOCl with the EndoActivator system (60 s); G6, 30-gauge syringe irrigation with NaCl (60 s). The pattern of colonization was visualized by scanning electron microscopy. The root canals were sampled by flushing with saline solution at baseline and after the treatments. The number of bacteria in each canal was determined by plate count. The presence and the absence of E. faecalis in root canals were also demonstrated by polymerase chain reaction (PCR).

RESULTS

There was a significant reduction in the bacterial population after all treatments (P < 0.001). The PAD, using both laser systems, and the sonic activated NaOCl irrigation were significantly more effective than diode irradiation and single NaOCl irrigation in reducing CFUs (P < 0.05). High-power diode laser and single NaOCl irrigation had an equal antibacterial effect (P > 0.05).

CONCLUSIONS

The PAD and EndoActivator system were more successful in reducing the root canal infection than the diode laser and NaOCl syringe irrigation alone.

Irrigants for non-surgical root canal treatment in mature permanent teeth

BACKGROUND

Root canal treatment is carried out on teeth in which irreversible pulpitis has led to necrosis of the dental pulp. As a treatment option it is an alternative to dental extraction. Mechanical preparation and irrigation with antiseptic or antibacterial solutions destroys bacteria and cleans the infected root canal. Irrigants should be effective in deactivating bacteria in the entire root canal space without causing any adverse tissue reactions. Sodium hypochlorite (NaOCl) and chlorhexidine are commonly used but there is uncertainty as to which solution, concentration or combination is the most effective.

OBJECTIVES

To assess the effects of irrigants used in the non-surgical root canal treatment of mature permanent teeth.

SEARCH METHODS

We searched the Cochrane Oral Health Group's Trials Register (to 5 July 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 4), MEDLINE via Ovid (1950 to 5 July 2012), EMBASE via Ovid (1980 to 5 July 2012), LILACS via BIREME (1980 to 5 July 2012). There were no restrictions regarding language or date of publication.

SELECTION CRITERIA

Randomised controlled trials in single or multi-rooted permanent teeth with pulpal or periapical pathology or both, which require root canal treatment. Irrigants either against each other or against inactive irrigant or placebo. Combinations of irrigants were allowed and if used in conjunction with EDTA (ethylenediaminetetra-acetic acid) or similar chelating agents.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed risk of bias of included trials and extracted data.

MAIN RESULTS

We included 11 trials involving 851 participants with 879 teeth which had undergone root canal treatment and involved the use of irrigants. Two trials were assessed as being at low risk of bias, with six unclear and three high. Four trials compared sodium hypochlorite versus chlorhexidine, however, no primary outcomes and only one secondary outcome, bacterial growth cultures, was reported for two of these trials (20% and 50% of teeth in the control group had positive bacterial culture). The meta-analysis indicated no strong evidence of a difference in the existence of bacterial growth between the interventions (risk ratio 0.73; 95% confidence interval 0.34 to 1.56; P = 0.41). The seven remaining trials each compared different interventions and only two of these trials included useable data on the primary outcomes of swelling and pain. One trial compared sodium hypochlorite 5.25% alone versus sodium hypochlorite 5.25% combined with hydrogen peroxide 3%, and versus normal saline and reported pain at 3 to 14 days after the procedure. There was no evidence of a difference in pain between the three groups. The other trial compared sodium hypochlorite 5% versus sodium hypochlorite with 'proteolytic enzyme', and there was no evidence of a difference in swelling between the groups. Two further trials reported bacterial growth, and three trials failed to report any data which could be used in the review. None of the included trials reported any data on adverse effects nor radiological changes in periapical radiolucency.

AUTHORS' CONCLUSIONS

Although root canal irrigants such as sodium hypochlorite and chlorhexidine appear to be effective at reducing bacterial cultures when compared to saline, most of the studies included in this review failed to adequately report these clinically important and potentially patient-relevant outcomes. There is currently insufficient reliable evidence showing the superiority of any one individual irrigant. The strength and reliability of the supporting evidence was variable and clinicians should be aware that changes in bacterial counts or pain in the early postoperative period may not be accurate indicators of long-term success. Future trials should report both clinician-relevant and patient-preferred outcomes at clearly defined perioperative, as well as long-term, time points.

Genetic predisposition to persistent apical periodontitis

INTRODUCTION

The proinflammatory cytokine interleukin (IL)-1 is a key regulator of host responses to microbial infection and a major modulator of extracellular matrix catabolism and bone resorption. Allele2 of IL-1β is associated with a four-fold increase in IL-1β production. The aim of this case-control study was to evaluate the gene polymorphism of IL-1β in the pathogenesis of endodontic failure. We hypothesized that the gene polymorphism (allele2 of IL-1β) would influence host response and enhance inflammatory reactions predisposing to persistent apical periodontitis (PAP).

MATERIALS AND METHODS

Subjects with at least 1 year of follow-up after root canal therapy (RCT) were recalled. Inclusion and exclusion criteria were applied, and 34 subjects with signs/symptoms of PAP with otherwise acceptable RCT were included. Sixty-one controls showed healing with acceptable RCT. Genomic DNA from buccal mucosa was amplified by polymerase chain reaction followed by restriction fragment length polymorphism to distinguish the alleles of IL-1β gene polymorphism.

RESULTS

A significant difference in the distribution of the polymorphic genotype among cases (70.6%) and controls (24.6%) (P < .001, Pearson χ(2)) was shown.

CONCLUSIONS

These findings suggest that specific genetic markers associated with increased IL-1β production may contribute to increased susceptibility to PAP.