Complications following an accidental sodium hypochlorite extrusion: A report of two cases

Sodium hypochlorite accident diagnosis and management: Analysis from the literature and the French pharmacovigilance database

PURPOSE

Sodium hypochlorite (NaOCl) is considered as the reference irrigation solution in endodontics. However, NaOCl-related accidents may occur, and non-dentist health professionals might under-recognize this rare adverse effect although it is potentially severe, with possible medical and aesthetic sequelae. We performed a literature review to provide to non-dentist healthcare professionals a large picture of symptoms, management and potential consequences of NaOCl accidents.

METHODS

We queried PubMed and the French Pharmacovigilance database and retrieved 76 cases for analysis (70 from 57 published articles, and six from the database).

RESULTS

The analysis showed that patients were mostly women (79%), aged around of 42 years, undergoing upper jawbone (74%) endodontic procedure. NaOCl concentration ranged from 1% to 10%, with 0.5 to 30 mL injected. Most cases (86%) corresponded to an accidental extrusion beyond the root apex to the periapical tissues, followed by tissular injection by error (8%) and extrusion into the maxillary sinus (3%). Local symptoms always occurred within 24 h, mostly pain (99%), edema (89%) and/or ecchymosis (61%). Complications were mainly neurological (29%), necrotic (22%) and cutaneous (9%). Most of patients (76%) fully recovered after medical management but 18 (24%) required surgical management.

CONCLUSION

Any healthcare professional should be aware of the classical symptomatic triad of NaOCl accident with sudden pain, haemorrhage/ecchymosis and swelling, to start or recommend adequate management. Patients should be reassured, but a close follow-up is necessary to avoid delayed complication.

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.

Comparative Evaluation of Dental Pulp Tissue Dissolution Ability of Sapindus mukorossi and Sodium Hypochlorite

Background The Sapindus mukorossi (SM) extract has been reported to possess antibacterial, antifungal, anti-inflammatory, and antioxidant characteristics. However, there is limited research demonstrating the effectiveness of SM in dissolving dental pulp tissue. Methods In an in vitro investigation, pulp tissue samples were extracted from human teeth, collectively weighing 144 mg. These samples were divided equally and activated by manual digital agitation (MDA) or ultrasonic (US) irrigation for three 30-second cycles with a resting period of 45 seconds between each activation. The samples in each group were sub-categorized into a set of three groups based on the treatment received as normal saline (NS), 5.25% sodium hypochlorite (Hypo), or Sapindus mukorossi (SM). Statistical tests, including the student t-test and one-way analysis of variance (ANOVA), were employed to compare the mean weight differences among the groups, with a significance level set at p ≤ 0.05 for all comparisons. Results The one-way analysis of variance (ANOVA) and independent t-test revealed significant intergroup differences (p<0.05). Turkey's post hoc analysis indicated significant distinctions, particularly when comparing Hypo with the other two irrigants, namely Hypo-NS (p<0.05) and Hypo-SM (p<0.05) when the MDA method was employed. Considering only the method adopted, the US technique was significantly superior (p=0.04) to the MDA. Conclusion Sapindus mukorossi (SM) demonstrated efficacy in dissolving pulp tissue but was not as effective as sodium hypochlorite (Hypo) which is the standard agent for root canal irrigation. SM to be used as an alternative to Hypo on clinical grounds needs further validation from research.

Evidence-based Standard Operating Procedures FoR the Prevention and Management of Sodium Hypochlorite Accidents in Dentistry

This article aims to reduce harm and improve patient safety in dentistry by providing evidence-based guidance on the prevention, recognition, management, and reporting of sodium hypochlorite injuries occurring in the course of endodontic dental treatment. In contrast to previous publications all types of sodium hypochlorite harm and near-harm events in the dental setting are considered, to offer the reader an all-encompassing clinical guide for reference.

Advances in the Role of Sodium Hypochlorite Irrigant in Chemical Preparation of Root Canal Treatment

Irrigation of root canal system is of great significance to the success of endodontic treatment, where sodium hypochlorite (NaOCl) is the most widely used irrigant in chemical preparation. NaOCl functions by eliminating bacterial biofilms and dissolving organic tissue, which may vary according to several factors such as the microbiology of root canal infection and the concentration of the irrigant. It has been proposed that the effectiveness of NaOCl could be enhanced via several methods, including heating the irrigant, applying in conjunction with certain reagents, or activating by agitation techniques. Despite its antibacterial and tissue-dissolving capacities, NaOCl should be used with caution to avoid detrimental effect due to its cytotoxicity and negative effect on dentin properties. In this narrative review, we discussed the factors that affect the properties of NaOCl, the methods to improve its efficacy, and the side effects that might occur in clinical practice.

Antibacterial potential of riboflavin mediated blue diode laser photodynamic inactivation against Enterococcus faecalis: A laboratory investigation

OBJECTIVES

This study aimed to evaluate the inactivation potency of riboflavin-mediated blue diode laser photodynamic inactivation (PDI) against Enterococcus faecalis at planktonic and biofilm stages and also investigated its effect on the tooth color change.

MATERIALS AND METHODS

The antibacterial and antibiofilm activities of riboflavin mediated PDI against E. faecalis were investigated. The numbers of colony-forming units (CFUs)/mL were calculated. Teeth discoloration were evaluated using the CIE L*a*b* based color difference (ΔE).

RESULTS

Antibacterial analysis indicated that the blue diode laser irradiation at 12, 18, 24, and 30 J/cm² alone and different concentrations of riboflavin solution (6.25 to 100 μM) reduced the number of CFU/mL of E. faecalis, but the reduction was not statistically significant (P > 0.05). Depending on the riboflavin concentration and the light dose, there can be as much as a 1-log effect on CFU/mL. In addition, E. faecalis biofilm was more affected with 30 J/cm² irradiation dosage and 100 μM riboflavin than other groups. Meanwhile, bacterial suspensions treated with 5.25% sodium hypochlorite (NaOCl) showed maximum biofilm inhibition and colony number reduction, compared with the control. The teeth exhibited clinically acceptable color change after riboflavin treatment at concentration ranging from 6.25 to 50 μM (ΔE < 3.7).

CONCLUSIONS

The riboflavin mediated PDI process is somewhat less effective than NaOCl but perhaps less toxic to tissues. It might be feasible to repeat the riboflavin + light treatment to further promote efficacy.

Influence of different irrigant activation methods on apical debris extrusion and bacterial elimination from infected root canals

Introduction

The study aimed to determine the apical debris extrusion and microbial elimination from infected root canals after using different irrigant activation methods.

Materials and Methods

Forty freshly extracted human mandibular premolars were selected and randomly assigned to four groups (n = 10). The teeth were mechanically prepared, sterilized, and inoculated with Enterococcus faecalis for 1 week. Irrigation was done with 3% sodium hypochlorite following conventional syringe irrigation-Group 1, manual dynamic agitation (MDA)-Group 2, passive ultrasonic irrigation (PUI)-UltraX -Group 3, and sonic irrigation (SI)-EndoActivator -Group 4, and the extruded debris were collected using Myers and Montgomery model. The microbial samples were taken from the canals using sterile paper points, cultured and recorded as colonies. The amount of extruded debris was measured by subtracting the final weight of the Eppendorf tube with debris from the initial weight of the tube.

Results

I. Group 3 showed the least apical debris extrusion (P < 0.05), followed by Groups 2 and 1 and the highest with Group 4. II. Group 3 showed the least colony-forming units (CFUs)/ml, followed by Group 4, and finally, Group 2 showed lesser mean CFUs/ml compared to Group 1 (P < 0.05).

Conclusion

All the irrigation activation methods were associated with apical debris extrusion, with the PUI system extruding the least amount of debris compared to the other groups. Irrigation activation techniques were beneficial in reducing the microbial load from the infected canals with the PUI system showing a complete elimination of the microbes, followed by SI and MDA.

Factors influencing the occurrence and progress of sodium hypochlorite accident: A narrative and update review

Sodium hypochlorite (NaOCl) is one of the most commonly used irrigant because of its several advantages. However, it is highly cytotoxic and can lead to severe tissue damage. NaOCl accident occurs when it is extruded beyond root confines into periapical or periradicular tissues. It is an irrigant mishap which can be life threatening and/or cause residual or long term or permanent consequences with malpractice and medico-legal implications. There are many factors which can influence the occurrence and progress of NaOCl accident. These factors can be broadly categorized as patient (host)-, tooth-, operator-, and NaOCl-related factors. They can be further categorized as predisposing and extent factors. It is vital for a clinician to thoroughly understand and identify various influencing factors to prevent NaOCl accident with its associated consequences including any potential medico-legal issues. The purpose of this article is to provide a narrative review on various factors which predispose to the occurrence of NaOCl accident and influence its extent and/or outcome.

Facial hematoma of endodontic origin: A case report

Endodontic treatment is a common procedure in dentistry that consists of elimination of organic tissues, infected debris, and pathogenic bacteria from the canal system by means of mechanical instrumentation associated with abundant disinfecting agents (Haapasalo et al., 2005) [1]. Despite progress with its implementation, dentists may at any time be faced with complications during or after a root canal procedure. While some of these problems can be anticipated, many can never really be predicted. A complication such as a hematoma that is usually seen as a complication of trauma or oral surgery, is rarely seen after a simple endodontic treatment. It put the dentist in a confused and uncomfortable situation. Dentists should be aware of the possible occurrence of this incident and should know what can cause it and how to manage it.

We report the case of a 63-year-old patient, referred by her general dentist to our center for the sudden onset of a facial hematoma after endodontic treatment.

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Facial Hematoma is a well-known and recognized complication in oral and maxillofacial surgery or in facial trauma.

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Hematoma is a rare, unknown, and unexpected complication after routine canal therapy.

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It can be an accident of sodium hypochlorite by extrusion of the solution through root apices.

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It is responsible of important morbidity.

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To avoid hypochlorite accidents, particularly hematoma, some recommendations must be followed, and the basics of endodontic treatment must be respected.

Dataset of endodontic microorganisms killed at 265 nm wavelength by an ultraviolet C light emitting diode in root canals of extracted, instrumented teeth

Ultraviolet C (UVC) light emitting diode (LED) can kill the endodontic pathogen Enterococcus faecalis and has the potential to kill other oral microorganisms associated with endodontic infections. This same bacteriocidal device shows great promise in the stimulation of periapical healing and pain reduction resulting from inflammation in root canals. Previously, we found that 255 nm UVC LED killed E. faecalis and induced the production of cellular biomarkers in HEPM cells and gingival fibroblasts (Morio et al., 2019). Here, we extend those findings and hypothesize that UVC LED at other wavelengths and power levels kill microorganisms associated with root canal infections. Units emitting UVC LED at 265 nm (12 mW), 265 nm (22.5 mW), and 280 nm (8 mW) wavelenths were assembled and the energy levels of their emissions were measured. The energy doses in millijoules (mJ) were calculated from the power readings of the meter (µW) × time of exposure (seconds). Ex vivo models of root canals were prepared in extracted, instrumented, single canal human premolars. Five cultures of microorganisms were treated with 265 nm (12 mW), 265 nm (22.5 mW), or 280 nm (8 mW) UVC LED on discs in laboratory assays and 4 cultures of microorganisms were treated with 265 nm (22.5 mW) UVC LED in root canals of extracted, instrumented teeth. After UVC LED treatment, all microorganisms were cultivated on microbiological media. Colony forming units (CFU) of viable microorganisms treated with UVC LED were counted and compared with those of viable microorganisms not treated with UVC LED as controls. Tukey's Honestly Significant Difference was used to determine statistical significances (0.05). Units emitting UVC LED at 265 nm (12 mW), 265 nm (22.5 mW), and 280 nm (8 mW) killed Candida albicans, Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), E. faecalis, and Streptococcus sanguinis after 30-90 seconds of exposure in laboratory assays (p < 0.05). Microbial killing differed among treatment times, UVC LED wavelengths, power levels of each unit, and specific microorganism. The unit emitting UVC LED at 265 nm (22.5 mW) killed C. albicans, S. aureus, MRSA, and E. faecalis in 30 s in root canals of extracted, instrumented teeth (p < 0.05). This dataset can be reused to assess the ability of other wavelengths and power levels to kill microorganisms as well as improve procedures for treating endodontic infections and inflammation in root canals.

An innovative technique to safely perform active cleaning in teeth with open apices: CAB technique

The current study aims to evaluate in vitro the extrusion of NaOCl, using an artificial root canal with an open apex, using different canal irrigation protocols. For this study, a transparent artificial root canal was used. The apex was shaped to be oversized and irregular in form. After root canal mechanical shaping, the artificial cylindrical chamber, which was made below the large apical foramen, was filled with fuchsine-stained bovine pulp tissue. Afterward, irrigation protocols were carried out and compared regarding their safety with regards to irrigant extrusion. Subsequently, the examiner created two groups, Group A: internal heating associated with ultrasonic activation and Group B: internal heating associated with ultrasonic activation, using the CAB technique. In both the groups, 5.25% sodium hypochlorite solution was used as the irrigant. Regarding assessing the presence or absence of the extrusion, photographs at ×20 were taken and analyzed. For the statistical analysis, a t-test for paired samples was used. Extrusion of irrigant beyond the apex was present only in Group A. The main objective of endodontic treatment is the removal of damaged tissues and bacteria. For this reason, active cleaning is crucial in all endodontic treatment cases. Internal heating followed with ultrasonic activation while using the CAB technique was an effective and safe technique to ensure no irrigant extrusion beyond the open apex.

Root Canal Disinfection Using Highly Effective Aggregation-Induced Emission Photosensitizer

Root canal (RC) therapy is the primary treatment of dental-pulp and periapical diseases. The mechanical method and chemical irrigation have limitations in RC therapy. Much attention has focused on exploring more controllable and efficacious antimicrobial methods. Although the introduction of photodynamic therapy (PDT) has provided the ideas for RC debridement, the problems of low photosensitive efficiency and nonsignificant germicidal potency of traditional photosensitizers (e.g., methylene blue) have not been solved. Since the concept of "aggregation-induced emission" (AIE) was proposed, optimization of photosensitizers has been boosted considerably. Herein, an AIE photosensitizer, DPA-SCP, with a strong ability to generate singlet oxygen, is proposed for use as an antibacterial application in infected RCs. The antimicrobial activity of DPA-SCP against Enterococcus faecalis suspensions was tested. To explore the antibacterial ability of this photosensitizer against bacterial-biofilm colonization on the inner walls of RCs, we established a model of bacterial biofilm infection. PDT mediated by DPA-SCP had a significant germicidal effect on E. faecalis suspensions and 21-day biofilms in human RCs. PDT mediated by DPA-SCP could achieve efficiency equivalent to that observed using 1% NaOCl, and lead to no significant change in the dentin surface, chemical corrosion, or cytotoxicity.

Apical Pressure Generated Using Conventional Syringe Irrigation in Immature Teeth-An In Vitro Study

This in vitro study aimed to evaluate apical pressure during irrigant delivery with syringe irrigation in immature teeth with an open apical foramen. Conventional syringe irrigation was performed in a 3D-printed immature incisor. A 5 mL syringe combined with 25 G and 30 G cannulas was used. Open-ended and side-vented needle tip designs were assessed. Cannulas were placed at tooth length (TL), TL −1 mm, TL −2 mm, and TL −4 mm. The syringe plunger was moved with a force of 10 N, 20 N, 40 N, and 80 N to simulate clinical conditions. A pressure sensor measured periapical pressures during irrigation. Each experiment was repeated 10 times. Data were analyzed descriptively (maximum, mean, standard deviation, 95% CI) with the critical threshold indicative of extrusion set at 7.64 mbar. 30 G cannulas with both needle tip designs never exceeded the threshold at any TL with a plunger force of 10–40 N. At 80 N, 30 G open-ended cannulas exceeded the threshold in 10%, 30 G side-vented in 20–60% of the measurements. At any TL, 25 G open-ended cannulas and 25 G side-vented cannulas never crossed the threshold with forces of 10–20 N and 10 N, respectively. Consequently, 30 G cannulas with both designs can be recommended for irrigant delivery in immature teeth. 25 G cannulas ought to be used with caution.

Use of electromagnetic stimulation on an Enterococcus faecalis biofilm on root canal treated teeth in vitro

Root canal disinfection is of utmost importance in the success of the treatment, thus, a novel method for achieving root canal disinfection by electromagnetic waves, creating a synergistic reaction via electric and thermal energy, was created. To study electromagnetic stimulation (EMS) for the disinfection of root canal in vitro, single rooted teeth were instrumented with a 45.05 Wave One Gold reciprocating file. Specimens were sterilized and inoculated with Enterococcus faecalis ATCC 29,212, which grew for 15 days to form an established biofilm. Samples were treated with 6% sodium hypochlorite (NaOCl), 1.5% NaOCl 1.5% NaOCl with EMS, 0.9% saline with EMS or 0.9% saline. After treatments, the colony forming units (CFU) was determined. Data was analyzed by Wilcoxon Rank Sums Test (α = 0.05). One sample per group was scored and split for confocal laser scanning microscopy imaging. There was a significant effect with the use of NaOCl with or without EMS versus 0.9% saline with or without EMS (p = 0.012 and 0.003, respectively). CFUs were lower when using 0.9% saline with EMS versus 0.9% saline alone (p = 0.002). Confocal imaging confirmed CFU findings. EMS with saline has an antibiofilm effect against E. faecalis and can potentially be applied for endodontic disinfection.

Calcium hypochlorite on mouse embryonic fibroblast cells (NIH3T3) in vitro cytotoxicity and genotoxicity: MTT and comet assay

Antimicrobial irrigation solutions are widely used under clinical settings. Their effect on dental tissue is a subject of recent research, which aims for a safer irrigant for clinical use. In this regard, here our goal was to evaluate the cytotoxicity and the genotoxicity of calcium hypochlorite (Ca(OCl)₂) solution, along with NaOCl, on Mouse embryonic fibroblast cells (NIH3T3). First, Cells were treated either with NaOCl or Ca(OCl)₂ in a time- and dose-dependent manner for cytotoxicity by 3-(4,5-dimethylthiazolyl-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, then cell viability was calculated according to cell proliferation plots. Secondly, genotoxicity was assessed by Comet assay. Data were statistically analyzed by Tukey's test (P < .05). NaOCl and Ca(OCl)₂ had similar effects on cellular viability at 3 and 6 h treatments. Cell viability of Ca(OCl)₂ at concentrations of 0.0125%, 0.025%, 0.05%, or 0.125% was significantly lower than that of NaOCl at 24 h treatment (P < .05).Comparing Ca(OCl)₂ and NaOCl treatments at all time points and concentrations, the damaged cell number of Ca(OCl)₂ was almost fourfold higher than that of NaOCl. In conclusion, both, NaOCl and Ca(OCl)₂ solutions were cytotoxic and genotoxic to NIH3T3, however, Ca(OCl)₂ had a significantly higher damaged cell percentage than NaOCl at all time points and concentrations investigated.

Endodontic irrigants: Different methods to improve efficacy and related problems

Shaping and cleaning a root canal system along with the preservation of the surrounding periodontal tissues are the principal goals of an endodontic treatment. While most of the attention is paid to the mechanical aspects of a root canal treatment, an essential feature of it is the irrigation. All over the years, many materials have been used to clean the root canal of a tooth, and certainly, the sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid solutions are the most used and most reliable ones. Putting them inside of a canal is mostly done using a normal syringe, but many techniques have been involved in this process, including the use of sonic/ultrasonic instruments, the use of shaping files, and even laser, to increase the efficacy of irrigant solutions, especially of NaOCl one. Each one of this technique faces some disadvantages, just as the vapor lock effect and the apical extrusion, and has a different action on features such as the reaction rate and the shear stress of an endodontic irrigant solution. In this narrative review, we describe the different features of many irrigant solutions and the different ways of upgrading their efficacy in the cleaning of a root canal system, with the use of tables to summarize the entire description, and drawing the readers' attention to a photographic illustration for a better understanding of the topic.

A Review of Medicolegal Considerations of Endodontic Practice for General Dental Practitioners

Treating a live human being to their health has been considered as a noble profession since the ancient times. Doctors are duty bound by their professional ethics to provide the best treatment to their patients. Endodontics is the specialty branch of the dental science of saving natural teeth in the oral cavity. During endodontic procedures, a mishap can occur any time in a day-to-day practice and may be treated as negligence which in turn ends into some legal complications. To prevent and tackle such future medicolegal issues related to endodontic treatment, the knowledge of the legal aspect of such clinical situation is necessary.

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.

N-acetylcysteine infusion in preventing hepatotoxicity secondary to intravenous injection of household bleach

We present a case of non-accidental injection of 40 ml of domestic bleach through a long-term central venous catheter (CVC) with subsequent AKI, and for the first time in the literature severe coagulopathy and acute liver injury. We detail the clinical course of events and our management plan which adds to the body of evidence for prognosis and treatment in these unusual cases.

Anatomy of sodium hypochlorite accidents involving facial ecchymosis - a review

OBJECTIVES

Root canal treatment forms an essential part of general dental practice. Sodium hypochlorite (NaOCl) is the most commonly used irrigant in endodontics due to its ability to dissolve organic soft tissues in the root canal system and its action as a potent antimicrobial agent. Although NaOCl accidents created by extrusion of the irrigant through root apices are relatively rare and are seldom life-threatening, they do create substantial morbidity when they occur.

METHODS

To date, NaOCl accidents have only been published as isolated case reports. Although previous studies have attempted to summarise the symptoms involved in these case reports, there was no endeavour to analyse the distribution of soft tissue distribution in those reports. In this review, the anatomy of a classical NaOCl accident that involves facial swelling and ecchymosis is discussed.

RESULTS

By summarising the facial manifestations presented in previous case reports, a novel hypothesis that involves intravenous infusion of extruded NaOCl into the facial vein via non-collapsible venous sinusoids within the cancellous bone is presented.

CONCLUSIONS

Understanding the mechanism involved in precipitating a classic NaOCl accident will enable the profession to make the best decision regarding the choice of irrigant delivery techniques in root canal débridement, and for manufacturers to design and improve their irrigation systems to achieve maximum safety and efficient cleanliness of the root canal system.