Journal of International Oral Health

REVIEW ARTICLE
Year
: 2023  |  Volume : 15  |  Issue : 4  |  Page : 319--327

Efficacy of EndoActivator on the postoperative pain in the teeth with symptomatic irreversible pulpitis: A systematic review and meta-analysis


Kiranmayi Govula, Gnyani Prasad, Yendluri Pavan Kumar, Maddineni Kowmudi, Sannapureddy Swapna, Niharika Mungara 
 Department of Conservative Dentistry and Endodontics, Narayana Dental College and Hospital, Nellore, Andhra Pradesh, India

Correspondence Address:
Dr. Kiranmayi Govula
Department of Conservative Dentistry and Endodontics, Narayana Dental College and Hospital, Nellore 524002, Andhra Pradesh
India

Abstract

Aim: Postoperative pain affects the quality of life and upsets clinicians and patients, which could cause postoperative discomforts such as pain, swelling, and persistent inflammation. Hence conventional irrigation methods are not sufficient to reduce the postoperative pain (PP). EndoActivator can reduce the risk of irrigant extrusion into periapical tissues to help patients and clinicians. The aim is to screen the clinical trials that compared the effect of activation of Irrigant by EndoActivator compared with without activation and the severity of pain after root canal treatment in the teeth with symptomatic irreversible pulpitis. Materials and Methods: Search criteria: PubMed/Medline, PubMed Central, Cochrane Library, EBSCO, EMBASE, Scopus Web of Science, DOAJ, LILAC, Manual search, Grey literature search. Randomized clinical trials, controlled clinical trials, or clinical studies were included which recruited patients with symptomatic irreversible pulpitis teeth with preoperative pain scores (moderate to severe) on a visual analogue scale and should have used activated irrigation by EndoActivator during root canal treatment and evaluated postoperative pain at different time intervals. The Risk of Bias (RoB) and meta-analysis were analyzed using review-manager software. Results: Four trials were judged to have a low RoB. There was a significant reduction in PP in the EndoActivator group at 8 and 24 h. There was a clinical significance difference between the activated and non-activated irrigation methods. Conclusion: The review has highlighted the need for irrigant activation in the regular clinical endodontic practice to increase the success rate and reduce PP, a crucial factor related to symptomatic irreversible pulpitis teeth.



How to cite this article:
Govula K, Prasad G, Pavan Kumar Y, Kowmudi M, Swapna S, Mungara N. Efficacy of EndoActivator on the postoperative pain in the teeth with symptomatic irreversible pulpitis: A systematic review and meta-analysis.J Int Oral Health 2023;15:319-327


How to cite this URL:
Govula K, Prasad G, Pavan Kumar Y, Kowmudi M, Swapna S, Mungara N. Efficacy of EndoActivator on the postoperative pain in the teeth with symptomatic irreversible pulpitis: A systematic review and meta-analysis. J Int Oral Health [serial online] 2023 [cited 2023 Sep 22 ];15:319-327
Available from: https://www.jioh.org/text.asp?2023/15/4/319/384664


Full Text

 Introduction



Successful root canal treatment relies on accurate diagnosis, meticulous clinical and radiological examination of root canals, proper access cavity followed by thorough cleaning and shaping and three-dimensional obturation.[1] Chemo-mechanical debridement removes pulpal tissue microorganisms, their byproducts, and debris using endodontic instruments and irrigants is a crucial phase in achieving the success of root canal treatment (RCT). Postoperative pain is an unpleasant unwanted, yet unfortunate, commonly occurring sensation after RCT, with an incidence ranging from 3% to 58%. Even severe pain may occur within 24–48 h after RCT. One prospective study has reported a 63% incidence of postoperative pain at 6 h and 51% at 18 h in the case of irreversible pulpitis teeth. The etiology of postoperative is multifactorial, which includes microbial factors, effects of chemical mediators, immune system cyclic nucleotide change, psychological factors and changes in local adaptation, and periapical tissue pressure changes, yet most common include extrusion of irrigants, medicaments, and apical debris. Symptomatic irreversible pulpitis is the most common pathologic condition and requires emergency treatment with spontaneous pain. It has been reported that postoperative pain in this condition is associated with preoperative pain up to 83% more than asymptomatic irreversible pulpitis condition, which is only 16%.[2]

Most areas left untouched with modern rotary instrumentation later become a harbor of debris microbes and their byproducts, resulting in reinfection or persistent periradicular inflammation, emphasizing the importance of irrigation and irrigant delivery methods. Irrigants, by their streaming forces and fluid dynamics, ensure optimal cleansing of the root canals, even in the most complex parts of the root canals.

Although conventional needle irrigation is most commonly used in routine endodontics under low pressure, it can deliver irrigant just 1 mm beyond its tip, giving space and a chance for microbes to thrive even after biomechanical preparation, especially in the apical third of the root where there are many anatomical complexities present such as accessory canals, lateral canals, isthmus, fins, and anastomoses. If we increase the pressure in the syringe, the irrigant may extrude along with debris into periapical tissues from the apical foramen leading to postoperative pain. Irrigation devices have been developed for safe delivery throughout the root canal using high-frequency low-frequency ultrasonics, sonic energy, mechanical brushing action, and vibrators to activate like vibringe passive ultrasonic irrigation, negative apical pressure, or simple manual agitation. Sonic devices operate at lower frequencies (<200 Hz) and include the Vibringe and EndoActivator systems. The EndoActivator sub-sonic system is an electrically driven unit operating at stated frequencies of 33, 100, and 167 Hz but with measured vibrational frequencies of 160, 175, and 190 Hz, respectively. The system consists of polymer tips of different sizes (size 15.02 taper, size 25.04 taper, size 35.04 taper) to agitate irrigants, potentially avoiding the risks associated with ultrasonically-driven metal instruments. These tips do not cut the dentin allowing safe activation of various intracanal irrigants and could produce intracanal fluid agitation. Increasing awareness and upgrading knowledge among clinicians and postgraduates in the application of EndoActivator in their daily routine clinical procedures needs more literature support and visibility. Clinical trials were done using EndoActivator, but no literature was available highlighting its efficiency.

A systematic review and meta-analysis are indicated as they gather all empirical research and stand with the highest quality of evidence. Hence the aim is to systematically review and critically analyze the effectiveness of EndoActivator activated irrigation in reducing postoperative pain in symptomatic irreversible pulpitis teeth.

 Materials and Methods



Research question

A research question: What is the Effect of the Endo Activator activated irrigation on postoperative pain in the teeth with symptomatic irreversible pulpitis?

Protocol

The systematic review was done according to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines.

PICOS

Problem/population—Adults patients with symptomatic irreversible pulpitis teeth that required RCT with preoperative pain scores ranging from moderate to severe on the visual analogue scale (VAS) pain scale.

Intervention—Activation of the irrigant using EndoActivator.

Comparison—Irrigation without activation, using positive apical pressure irrigation or conventional needle irrigation.

Outcome—(i) Postoperative pain intensity evaluation using the VAS pain scale, (ii) Analgesic Intake.

Study design—Systematic review and meta-analysis.

Search strategy

A broad search for articles included studies from 1981 to January 2021. The studies were formed from the databases namely PubMed, Web of Science, EBSCO, Scopus, Cochrane Library, DOAJ, LILAC, and Grey literature, along with manual search. The keywords used were activated irrigation EndoActivator symptomatic irreversible pulpitis postoperative pain in various combinations. The titles and abstracts of identified articles were independently evaluated by two researchers using an electronic search accompanied by a manual search.

Eligibility criteria

Randomized clinical trials, controlled clinical trials, or clinical studies were included in the systematic review, which selected patients with symptomatic irreversible pulpitis teeth with preoperative pain scores ranging from moderate to severe (40–100 mm) on a VAS (0–100 mm) that required root canal treatment. Trials that included should have had one group of patients who received activated irrigation by EndoActivator during root canal treatment and evaluated postoperative pain at different time intervals (8, 24, 48 h, and 1 week] using the VAS. Animal studies, systematic reviews, case reports, preliminary studies, and studies not in English were excluded from the consideration.

Selection of studies and quality assessment

Two review authors independently assessed the abstracts and titles identified as a result of this search strategy and included them based on the inclusion criteria. Full-text articles of selected abstracts were then assessed for eligibility. Using the Cochrane Risk of Bias (RoB) tool, two reviewers assessed the quality of the included studies of each study independently as having a low, unclear high RoB. It depends on the information provided in the included studies regarding randomization, allocation concealment, blinding of participant assessors and outcome data, and selective outcome reporting.

Data synthesis

Two independent authors conducted a quality assessment of the title and abstracts of included articles. The information was tabulated along with activated irrigation parameters such as author name, year, irrigant activation by EndoActivator, number of patients, reduction in postoperative pain, method of analysis of postoperative pain at different time intervals, and analgesic intake at those time intervals. The details are well explained in [Table 1].{Table 1}

Statistical analysis

Meta-analysis analyzed the reduction of postoperative pain at different time intervals in the form of the standard mean difference. The data obtained was dichotomous hence standard mean difference (SMD) and standard error were measured between the intervention and control groups at various time intervals. Also, the analgesic intake was analyzed from the included trials. Rev Man software (Review Manager [Rev Man] software developed by Cochrane Collaberation) was used to analyze and synthesize the data from the included studies. The heterogeneity among the included studies was measured as an I2 test. The fixed effect model was used to estimate as the heterogeneity of the studies is below 50%.

 Results



A thorough database search identified 193 citations and 53 through manual search. Two reviewers analyzed the abstracts and identified full-text articles that used EndoActivator after removing duplicates. Only four studies fulfilled the inclusion criteria of use of activation of Irrigant by EndoActivator in symptomatic irreversible pulpitis. The PRISMA flow diagram [Figure 1] represents the search strategy. A total of four articles were selected that activated irrigation using EndoActivator as an intervention during root canal treatment. Hence all four studies were subjected to qualitative and quantitative analyses.{Figure 1}

The main characteristics of the included studies are detailed in [Table 1]. All four studies had posterior teeth with symptomatic irreversible pulpitis, confirmed using clinical examination and periapical radiographs. The preoperative pain intensity was moderate to severe[3],[4],[5],[6],[7],[8],[9] on the VAS was included. All four studies used irrigation activation by EndoActivator as an intervention alongside passive ultrasonic (PUI), EDDY tip, and manual dynamic agitation and compared it with conventional needle irrigation. In all the studies, root canals were filled with 2 mL of 3% NaOCl, and then the EndoActivator tip was inserted into the canal short of working length and activated. 2 mL of 17% EDTA was then introduced into each canal and was activated by EndoActivator. The Results of the four included studies was mentioned in the [Table 3].{Table 3}

The RoB varied across the studies [Figure 2] and [Figure 3]. Randomization and allocation concealment were found to be adequate in all four studies. Blinding of participants and personnel and blinding of outcome assessors was judged to have a low RoB in all four included studies. According to the obtained findings, it was considered that the overall RoB across the studies was low.{Figure 2} {Figure 3}

Effects of interventions

All four trials reported demographic data. In these four studies, 423 patients with symptomatic irreversible pulpitis were evaluated. Three studies assessed postoperative pain in mandibular molars, and one study included both premolars and molars. All four studies had EndoActivator activated irrigation as an intervention, compared it with conventional needle irrigation, and measured postoperative pain intensity at various intervals using the VAS (0‒10 cm). The results were tabulated as statistical values of all four included studies and explained in detail in [Table 2].{Table 2}

Meta-analysis

Four articles were included for meta-analysis as the heterogeneity is low, which evaluated the primary outcome, reduction in postoperative pain at various time intervals like 8 h, 24 h, 48 h, 72 h, and 7th day. Two of the four studies evaluated analgesic intake as the secondary outcome. The forest plots demonstrated that all the meta-analyses presented a significant difference in the intervention group irrigant activation by EndoActivator. The standard mean difference was at a 95% confidence interval (CI).

Pain at 8 hours

After the root canal treatment along with the activation procedure, three studies reported postoperative pain at 8 h in the form of mean and standard deviation.[10],[11] There was a statistically significant difference in favor of the EndoActivator-activated irrigant group over the control SMD = –0.63; 95% CI, –0.92 to –0.34; I2 = 90% [[Figure 4]A].{Figure 4}

Pain at 24 hours

All the included four studies experienced postoperative pain at 24 h in the form of mean and standard deviation.[3],[10],[11],[12] There exists a statistically significant reduction in the pain intensity with activation by EndoActivator SMD = –0.59; 95% CI, –0.83 to –0.35; I2 = 71% [[Figure 4]B]. However, there was a low heterogeneity among studies with the EndoActivator method (I2 = 50% [[Figure 4]B]).

Pain at 48 hours

All four studies reported postoperative pain at 48 hours (VAS) in the form of mean and standard deviation. There was a slight reduction in postoperative pain with activation by EndoActivator, but no statistically significant difference between the activated and non-activated groups (SMD = –0.21; 95% CI, –0.45 to 0.02; I2 = 78% [[Figure 4]C]).

Pain at 7 days

Two studies reported this outcome where there was no statistically significant difference between the EndoActivator activated and other groups (SMD = –0.07; 95% CI, –0.35 to 0.21; I2 = 0% [[Figure 4]D]).[11],[12]

Use of analgesics

Two studies compared the number of analgesics taken between the intervention and comparison groups at 24 and 48 h and found a significantly lower rate of analgesic use in the EndoActivator group which reported that out of 40 patients, only three and 25, only one used analgesics.[10] The results of the outcome analgesic intake in the form of statistical values of two included studies were explained in detail in [Figure 4E] and F.

Risk of Bias

Two authors independently assessed the RoB in four selected studies using the Cochrane collaboration tool. The following domains were evaluated and classified as low, high, or unclear bias. All four included studies reported random sequence generation, allocation concealment, blinding of participants, and outcome assessors. Except for one study, the other three mentioned incomplete outcome data and selective reporting. Only one study presented the other bias. Hence the overall RoB in the four included studies in this review is considered low-RoB.

 Discussion



Summary of main findings

Whereas numerous in vitro studies have demonstrated the effectiveness of activated irrigation, their inclusion in standard endodontic therapy makes them more clinically reliable. Systematic review and meta-analysis of such clinical trials render the most substantial evidence high-quality evidence. Three key clinical features of outcome measures regarding irrigation that outline success are apical periodontium healing rate, antimicrobial efficacy, and postoperative pain. Pain following treatment is measured subjectively using a VAS form or scale of 0 to 100, with 10 or 100 being the most severe pain, respectively. Furthermore, the postoperative use of analgesics is also used as an outcome measure. Sonic irrigation was found to cause significantly less postoperative pain than needle irrigation at 8, 24, 48, and 72 h—patients treated with needle irrigation consumed significantly more analgesics from 0 to 24 h. It was proved that there was no significant difference between manual and sonic irrigation after standardizing irrigant volume and duration. However, it later resulted in significantly less pain than manual dynamic agitation and negative apical pressure technique.[10]

EndoActivator is a sub-sonic device that vigorously agitates the irrigant to disrupt the smear layer and biofilm by the hydrodynamic phenomenon, resulting in deep cleaning and disinfection. The incidence of postoperative pain is 30% more than other irrigation devices. Conventional needle irrigation delivers irrigant 1 mm beyond the needle tip and can cause extrusion in large and open apices. Studies have shown that traditional needle irrigation produces more significant postoperative pain, as VAS shows.[3] Also, the consumption of analgesics is more with a conventional needle. Positive pressure produces more significant hydraulic pressure may result in postoperative pain. Myers reported positive pressure of conventional needle extruded a greater debris weight apically. EndoActivator extrudes less debris than conventional needle irrigation and side vent needle. The EndoActivator showed less irrigant extrusion and was significantly lower than the PIPS PHAST Maxi probe. Spectrophotometric evaluation of irrigant extrusion showed EndoActivator is less than conventional needle irrigation.[4]

EndoActivator is clinically efficient in delivering the irrigant up to working length without causing postoperative pain and ensuring canal and isthmus cleanliness.[5] All four included studies included teeth with symptomatic irreversible pulpitis treated in a single visit and excluded the possible effect of necrotic infected pulps and the use of intracanal medicaments.[6] Pain reduction was also recorded in terms of the percentage of patients reporting a clinically significant reduction in pain in 4 trials.

Many clinical studies report that preoperative pain is the most affecting factor. Hence, the review included studies that recorded postoperative pain, and the studies that could not avoid confounding factors in postoperative pain relief were excluded.[7] The possible reasons for the decrease in postoperative pain with activated irrigation may be related to the movement in the cervical direction of the irrigating solution inside the root canal and reduced risk and amount of extrusion and damage to the periapical region.[8] Enhancement of irrigant solution dispersion because of machine-assisted agitation can be associated with better smear layer removal, debris tissue dissolution, and antimicrobial effect.[9]

Compared with standard care, clinical trials showed that activation of intracanal irrigant using EndoActivator significantly reduced postoperative pain intensity at 8 h and 1 day after the root canal procedure. Activation of irrigant by EndoActivator has reduced postoperative pain between 48 h and 7 days. Analgesic intake was less in the EndoActivator group in four trials. The systematic review is the first one that evaluated the effectiveness of EndoActivator in symptomatic irreversible pulpitis teeth.

The meta-analysis showed that preoperative pain intensity was a key factor regarding irrigant activation. It is in correlation with the other studies’ findings that suggested that the intensity of acute preoperative pain may significantly affect post-endodontic treatment pain.[13],[14] Primarily teeth with symptomatic irreversible pulpitis and symptomatic apical periodontitis are at high risk of developing postoperative pain.[14] However, our results suggest that activation of irrigant using EndoActivator has reduced postoperative pain, possibly because of less extrusion of debris and irrigant. Similar findings were reported by Iman and Al-Zaka[11] and Munoz and Camacho-Cuadra[15], in their studies using irrigant activation by EndoActivator conducted in the field of endodontics.

Validation of the studies, which was crucial, was performed to assess and weigh the RoB and strength of evidence.[16],[17] The information will help the clinicians use the activation of the irrigant more frequently in their regular practice. The clinical trials included in the review assessed the reduction of pain in patients who were expected to have moderate to severe postoperative pain, and relief from pain was urgent.[18],[19] The main reason for excluding studies was non-activated irrigation during endodontic treatment and the studies in which pulpal status was not mentioned.[20] Studies included in the results for posttreatment pain were considered for only symptomatic irreversible pulpits that presented with preoperative pain, and pain scores between the groups were evaluated at various time intervals.[21] Our systematic review showed that irrigant activation using EndoActivator in symptomatic irreversible pulpitis teeth would significantly reduce postoperative pain at 8 and 24 h, a crucial period.[22],[23] The analgesic intake is much reduced in the EndoActivator group at 24 h. The availability of limited clinical information on EndoActivator and included studies having limited sample sizes were the limitations in this review.[12],[24] The study’s critical appraisal was done using the AMSTAR 2-checklist tool, which showed all the essential points were reviewed in the review except for publication bias as the number of includes studied is small, less than 10.

Strengths and limitations

The systematic review had specific strengths like an extensive literature search to identify relevant studies, and the quality of the included studies was evaluated, which was a critical phase. The literature search included the top-rated journals in the endodontic field. The AMSTAR 2 checklist was used to rate the quality of the reported outcomes. Despite a good search, we might have missed identifying relevant clinical trials using an EndoActivator. The limited sample size might have led to overestimating the intervention effects.

Implications for research and clinical practice

Irrigation activation using an EndoActivator is an effective adjunct for controlling pain after root canal therapy. As per the results, activated irrigation has a pronounced effect in patients with symptomatic irreversible teeth with moderate to severe preoperative pain. Irrigant activation may also reduce the use of rescue medication after root canal therapy.[4] The effect of sonic irrigant activation, type of irrigant used, quantity, and time on the success of root canal treatment are yet to be known. An optimal amount of irrigant and irrigation duration has not been determined; however, most studies in the systematic review used 20 mL of sodium hypochlorite for 5 min. Therefore, clinical trials of Irrigant activation using EndoActivator should be well-designed to explore these outcomes in the future.

 Search Strategy



(Sonic irrigation techniques) AND (EndoActivator)) OR (Positive apical pressure irrigation)) OR (positive pressure irrigation)) OR (needle irrigation)) OR (conventional needle irrigation)) OR (syringe irrigation)) AND (symptomatic irreversible pulpitis)) OR (irreversible pulpitis)) AND (permanent mandibular molars)) AND (root canal therapy)) OR (endodontic therapy)) OR (root canal treatment)) OR (endodontic treatment) AND post endodontic pain OR postoperative pain AND (clinical trial) AND (randomized clinical trials)) OR (clinical studies)).

 Conclusion



Well-designed trials assessing the effectiveness of EndoActivator in patients with severe preoperative pain, symptomatic irreversible pulpitis, and the long-term success of EndoActivator activation are warranted. The systematic review and meta-analysis have concluded that activation of Irrigant by EndoActivator helped reduce postoperative pain after root canal treatment in the teeth with symptomatic irreversible pulpitis, especially in the first 24 and 48 hours, which were crucial for the patient with minimal anxiety.

Acknowledgement

We would like to acknowledge the contribution of our head of the department, senior staff members, and colleagues.

Financial support and sponsorship

Self-funded.

Conflicts of interest

There are no conflicts of interest.

Authors contributions

Concept or design: Dr. Kiranmayi G, Dr. Pavan Kumar Y.

Acquisition: Dr. Kowmudi M, Dr. Swapna Sannapureddy

Analysis: Dr. Kiranmayi, Dr. Pavan Kumar Y

Interpretation of data: Dr. Swapna Sannapureddy, Dr. Niharika M.

Drafting: Dr. Gnyani Prasad MGV, Dr. Kowmudi M, and Dr. Niharika M.

Ethical policy and Institutional Review board statement

Not applicable.

Patient declaration of consent

Not applicable.

Data availability statement

The data set presented within this manuscript has been obtained from the four included articles. The data were readily available within the articles.

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