Comparative evaluation of postoperative pain and periapical healing after root canal treatment using three different endodontic sealers: A randomized controlled clinical trial

Abstract

Aims:

A randomized controlled clinical trial to evaluate postoperative pain and investigate periapical healing after root canal treatment using eugenol, resin-based, and calcium silicate-based sealers (CSBSs) sealers.

Materials and Methods:

Sixty-three individuals diagnosed with apical periodontitis confirmed using cold test and electronic pulp tester, periapical pathology with periapical index score of 2 or more, previous endodontic treatment failure exhibiting a visual analog scale pain score of 3 or above, were enrolled in this investigation. The patients were randomly allocated into three groups and following biomechanical preparation, the canals were obturated using Meta CeraSeal, AH plus, and eugenol-based sealers. Postprocedural pain intensity was assessed at 24 h, 48 h, and 7 days, while periapical healing was evaluated at 3- and 6-month follow-ups. Statistical analysis was done using the Chi-square and Friedman’s test.

Results:

The mean of periapical lesions for Meta CeraSeal (4.7, 1.6), AH Plus (4.68, 3.19), 24 and eugenol-based (2.66, 1.75) at 3 months and 6 months, respectively. The mean & std. deviation of pain scores at 24 h for Meta CeraSeal (0.62 ± 1.857), AH Plus (1.62 ± 1.962), and eugenol-based (0.48 ± 1.250). At 48 h for Meta CeraSeal (0.33 ± 1.528), AH Plus (1.33 ± 1.798). On the 7^th day, Meta CeraSeal (0.24 ± 1.091) and AH Plus (0.71 ± 1.384) for eugenol-based at 48 h, and on the 7^th day, none of the patients had pain. Evaluation of the apical sealer puff displayed no suggestive variations (P = 0.634). Notably, no analgesics were taken.

Conclusions:

No suggestive dissimilarity was noted between eugenol, resin-based, and CSBSs sealers.

INTRODUCTION

A successful endodontic treatment lies in eradicating microorganisms associated with periapical pathology and achieving this requires a comprehensive root canal obturation to seal the apex against periapical tissue fluids, thereby impeding further microbial activity. Hence, the key objective is establishing an optimal microbiota conducive to anatomical healing, accomplished through meticulous root canal disinfection using irrigants such as sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid,[1] whereas endodontic sealers play a pivotal role in facilitating the healing of periapical inflammation.[2] Periapical healing is a complex process involving interactions between osteoclasts and osteoblasts, resulting in bone replacement both structurally and functionally[3] despite potential contact with periradicular tissues through lateral canals or apical foramina.[4] However, the presence of sealers can impede periapical healing by discharge through root apex and accessory canals.[5]

Therefore, the success of nonsurgical endodontic therapy depends on various factors, the choice of sealers and obturation techniques. Warm gutta-percha obturation with resin-based sealers (RBSs) such as AH Plus has traditionally been considered the benchmark for achieving satisfactory root filling.[6] Various studies state that AH Plus sealer deeply penetrates dentinal tubules, establishes a solid mechanical interlock with dentin, and exhibits favorable properties such as solubility, pH, calcium ion release, flow, and radiopacity.[7] The field of endodontics is continuously advancing due to innovation and development made in the field of dental materials. CeraSeal (Meta Biomed) is a newly launched syringe-type sealer incorporating calcium silicates, zirconium oxide, and a thickening agent hence has limited published research both in vitro and in vivo.[4] It has shown promising results regarding their physicochemical and antibacterial properties. They are known for their biocompatibility and ability to chemically bond to dentinal walls, thereby enhancing sealing ability within root dentin.[8] Therefore, a comprehensive assessment of biocompatibility is crucial to understanding their impact on reparative/regenerative responses utilizing stem cells from the periodontal ligament as models for cytotoxicity assessment of endodontic sealers have shown promise due to their multidirectional differentiation abilities and contribution to apical healing.[9] Postoperative pain is a multifaceted response, with reported incidence ranging from 3% to 58%, varying based on individuals’ pain thresholds and stimuli caused by injury to apical tissues.[10]

The study’s objective notably emphasizes that no prior research has assessed periapical healing and the success of endodontic retreatment by comparing the different types of endodontic sealers and their effects at various time intervals without including factors such as the use of intracanal dressing and the intake of analgesics. The present study aims to compare the incidence and occurrence of postoperative pain and assess periapical healing following endodontic therapy using zinc oxide eugenol (ZOE), AH Plus, and Meta CeraSeal sealers in patients diagnosed with apical periodontitis (AP), periapical pathology, and endodontic treatment failure. The null hypothesis posits that there is no significant difference among the three endodontic sealers.

MATERIALS AND METHODS

The current study adhered to the consolidated standards of reporting trials guidelines.

Institutional review board ethical clearance reference number: NIMSUR/IEC/2023/278. Registration of this trial was done prospectively in the Clinical Trials Registry-India with the registration number (REF/2023/08/071882) dated August 01, 2023, under review. All patients consented to an informed consent form discussing the risks and benefits associated with the study.

Trail design

The current study was carried out within a university environment employing a single-blind study. The operator cannot be blinded because of the different consistency of the material.

Study group

Currently, three groups were employed in the current study; Group I: ZOE sealer (Prime Dental, India), Group II: RBS (AH Plus), and Group III: Bioceramic sealer (BCS) (Meta CeraSeal).

Inclusion/exclusion criteria

The patient advised root canal treatment in maxillary and mandibular anterior and posterior within the age group of 18 years and above diagnosed with AP confirmed using cold test and electronic pulp tester, periapical pathology with a periapical index score of 2 or more using radiograph, previous endodontic treatment failure exhibiting Visual Analog Scale (VAS) pain score of 3 or above, were enrolled in this investigation. Patients with immature permanent teeth, root fractures, and external/internal root resorption were excluded.

Treatment protocol

Once enrolled in the current study, patients undergo a comprehensive medical and dental history evaluation. An intraoral examination was conducted, and a digital radiographic evaluation was performed. The treatment plan was explained, and their informed consent was obtained. Randomization into groups was achieved using GraphPad software. Following local anesthesia administration, rubber dam isolation using Waldent rubber dam kit (K16/2) was carried out, access cavity preparation was performed using an Endo Access Bur (Dentsply), and debridement of the pulp chamber. Initial patency filing with an ISO size 10 and 15 K-file (Mani Corp. Japan) and working length was confirmed using a radiograph. Instrumentation was done using a hand instrument starting from the first file binding the apex till three times bigger size file followed by a similar taper instrumentation technique using Waldent Wal-flex Gold rotary files 25 mm till 20/06. Irrigation with NaOCl (Prime Dental Products, Thane, India) was performed throughout the instrumentation process using a 2 mL syringe barrel (Dispovan, India). Obturation was carried out using a sealer based on the assigned group, with a master cone radiograph taken for reference. Sealer application using a Lentulo spiral was followed by obturation using the lateral compaction technique. Permanent restorations were completed using composite resin [Figure 1].

Figure 1.

(a) Preoperative radiograph, (b) Postoperative radiograph, (c) Follow-up radiograph at 3 months, (d) Follow-up radiograph at 6 months

Outcome assessment

Digital periapical radiographs were conducted using the parallel cone technique to establish the baseline data. Periapical lesion size was calculated using an X-ray grid with three experienced endodontists (NK, DS, DD) who confirmed the size at different intervals, and mean scores were taken. The interobserver agreement was seen at 0.90 using Cohen kappa (P < 0.05). Follow-up radiographs at 3 and 6 months were taken [Figure 1]. Sealer extrusion presence or absence was noted. In cases of sealer, extrusion associated pain and symptoms were assessed.

Posttreatment pain was evaluated using a VAS score consisting of 1–10 mm divided into 10 equal parts from 0 referred no pain, score 1–2 mild, 3–6 moderate, and 7–10 severe. The patients were asked to write in a sheet at 24 h, 48 h, and 7 days posttreatment followed by returning the pages on a recalled visit. Analgesic intake was also noted if any.

Statistical analysis

Data were entered into a Microsoft Excel sheet and analyzed using the SPSS (version. 26.0, IBM Corporation, Armonk. New York, USA) software. The Shapiro–Wilk’s test was conducted to check for normality, revealing that all variables deviated from a normal distribution. Consequently, nonparametric tests were employed, including the Chi-square test, Friedman test, and Mann–Whitney U-test. Friedman’s two-way analysis of variance was utilized to examine the differences in the mean area of periapical lesions within each group across various time intervals. P < 0.05 was considered indicative of statistical significance for these tests.

RESULTS

Out of 100 patients initially enrolled in the study, 27 were excluded due to various reasons such as pregnancy, diabetes, or refusal for follow-up from further analysis. The remaining 63 patients underwent further assessment [Figure 2]. Five failed to attend follow-up radiographs, while one experienced acute pain during treatment, leading to their exclusion from the study. Subsequently, the data collected from the participants were subjected to the analysis. Regarding patient characteristics, the mean age calculated was 29.81 years. Similarly, no statistically suggestive discrepancy was observed in the distribution of participants with a P = 0.624.

Figure 2.

Consolidated standards of reporting trials flowchart showing the present study’s design with an overview of the different treatment protocols, loss of patients to follow, and periapical healing analysis

The mean & std. deviation of pain scores at 24 h for Meta CeraSeal (0.62 ± 1.857), AH Plus (1.62 ± 1.962), and eugenol based (0.48 ± 1.250). At 48 h for Meta CeraSeal (0.33 ± 1.528), AH Plus (1.33 ± 1.798). On the 7^th day, Meta CeraSeal (0.24 ± 1.091), and AH Plus (0.71 ± 1.384) for eugenol based at 48 h, and on the 7^th day none of the patients had pain.

For Group I, the Friedman test yielded a P = 0.032 with a corresponding Chi-square value of 8.786. In Group II, the Friedman test resulted in a P = 0.00 and a Chi-square value of 22.60. In Group III, the Friedman test yielded a P = 0.014 along with a Chi-square value of 10.688. This indicates no statistical discrepancy in pain values across time intervals (P < 0.05) [Table 1a and Graph 1]. The intragroup comparison of pain variables for each group revealed no suggestive findings.

Table 1a:

Intra-group comparison of variables of pain using the Friedman test

Group & Variables	Mean	Std Deviation	Chi-Square value	P of Friedman test
Group I
Pain Post op	0.81	2.228	8.786	0.032*
Pain 24h	0.62	1.857
Pain 48h	0.33	1.528
Pain 7 day	0.24	1.091
GROUP II
Pain Post-op	2.0	2.236	22.600	0.000*
Pain 24h	1.62	1.962
Pain 48h	1.33	1.798
Pain 7 day	0.71	1.384
Group III
Pain Post-op	0.71	1.586	10.688	0.14*
Pain 24h	0.48	1.250
Pain 48h	0.00	0.00
Pain 7 day	0.00	0.00

Graph 1.

Intragroup comparison of variables of pain

Intergroup comparison of pain using the Kruskal–Wallis test the value of (P = 0.033), whereas the Chi-square value is 6.813 postoperatively. At 24 h the value of (P = 0.037), whereas the Chi-square value is 6.609. At 48 h the value of (P = 0.001), whereas the Chi-square value is 13.786. On the 7^th day the value of (P = 0.027), whereas the Chi-square value is 7.253 [Table 2 and Graph 1].

Table 2:

Inter-group comparison of variables of post-operative pain and periapical healing using the Kruskal-Wallis Test

	n	Mean	Std. Deviation	Chi-square value	P of Kruskal-Wallis Test
Pre-op
I	21	7.5	2.550	1.494	0.502#
II	21	6.25	3.262
III	21	4.60	2.63
Total	63	18.35	8.442
Post-op
I	21	6.3	2.402	1.381	0.512#
II	21	5.81	3.061
III	21	3.90	1.876
Total	63	16.01	7.339
3-months
I	21	4.7	3.151	0.823	0.665#
II	21	4.68	3.001
III	21	2.66	0.816
Total	63	12.04	6.986
6-months
I	21	1.6	2.435	1.988	0.378#
II	21	3.19	2.807
III	21	1.75	0.689
Total	63	6.54	5.931
Pain Post-op
I	21	0.81	2.228	6.813	0.033*
II	21	2.00	2.236
III	21	0.71	1.586
Total	63	1.17	2.091
Pain 24 H
I	21	0.62	1.857	6.609	0.037*
II	21	1.62	1.962
III	21	0.48	1.250
Total	63	0.90	1.766
Pain 48 H
I	21	0.33	1.528	13.786	0.001**
II	21	1.33	1.798
III	21	0.00	0.000
Total	63	0.56	1.457
Pain 7 day
I	21	0.24	1.091	7.253	0.027*
II	21	0.71	1.384
III	21	0.00	0.000
Total	63	0.32	1.045

The mean & std. deviation of periapical lesions post operatively for Meta CeraSeal (6.3 ± 2.402), AH Plus (5.81 ± 3.061), and 8 eugenol based (3.90 ± 1.876), at 3 months for Meta Ceraseal (4.7 ± 3.1t51), AH Plus (4.68 ± 3.001) and eugenol (2.66 ± 0.816), and 6 months, for MetaCeraseal (1.6 ± 2.435), AH Plus (3.19 ± 2.435) and eugneol (1.75 ± 0.689) respectively [Table 1b].

Table 1b:

Intra-group comparison of variables of periapical healing using the Friedman test

Group & Variables	Mean	Std. Deviation	Chi-Square value	P of Friedman test
Group I
Pre-op	7.5	2.550	14.105	0.002**
Post-op	6.3	2.402
3 months	4.7	3.151
6 months	1.6	2.435
Group II
Pre-op	6.25	3.262	19.798	0.0005**
Post-op	5.81	3.061
3 months	4.68	3.001
6 months	3.19	2.807
Group III
Pre-op	4.60	2.63	14.129	0.0075**
Post-op	3.90	1.876
3 months	2.66	0.816
6 months	1.75	0.689

The discrepancy in the mean area of the periapical lesion from baseline to 6 months, Group I the Friedman test yielded a P = 0.002 with a corresponding Chi-square value of 14.105. Group II the Friedman test yielded a P = 0.0005 with a corresponding Chi-square value of 19.798. Group III the Friedman test yielded a P = 0.0075 with a corresponding Chi-square value of 14.129. There was a statistically highly suggestive discrepancy seen for the values between the time intervals (P < 0.01) with higher values at preoperative [Table 1b and Graph 2]. These results demonstrate a consistent pattern across all groups, with higher values at the preoperative stage compared to 6 months postbaseline.

Graph 2.

Intragroup comparison of variables of periapical healing at x-axis and y-axis

Intergroup comparison of periapical healing using the Kruskal–Wallis test the value of (P = 0.512), whereas the Chi-square value is 1.381 postoperatively. At 3 months the value of (P = 0.665), whereas the Chi-square value is 0.823. At 6 months the value of (P = 0.378), whereas the Chi-square test is 1.988 [Table 2 and Graph 2].

A few patients underwent apical sealer puff unintentionally to further assess for any potential irritation or pain. Analysis indicated no statistically suggestive discrepancy in frequencies among the groups, with a P = 0.634 (P > 0.05). Notably, no antibiotics or analgesics were prescribed, and patients were advised against taking the medication without consulting their dentist.

DISCUSSION

Various studies suggest that BCSs cause less postoperative pain than other sealers, potentially due to their wettability and viscosity, which allow them to spread into root canal irregularities and noninstrumented spaces. BCSs also promote bioactivity and adhesion to the canal wall through mineral tags formed by the hydration of calcium hydroxide.[10] A similar result was concluded in a systematic review conducted by Mekhdieva et al., randomized controlled trials assessing postoperative pain after obturation using calcium silicate-based sealers versus traditional sealers found that BCSs were linked to notably reduced short-term postoperative pain, lesser opioid use, and fewer flare-ups.[11] Chopra et al., a systematic review assessing clinical and radiographic outcomes of root canal therapy BCSs versus RBSs in young adults concluded that BCSs demonstrated comparable performance to RBSs regarding postoperative pain levels, risk of inception, and pain intensity at both 24 and 48 h. These results endorse the need for conducting randomized clinical trials in future.[12] However, similar results were observed in the current study suggesting no notable discrepancies in mean pain scores among the three groups were found during the 48-h postoperative evaluation period, suggesting that the provided operator adhered to the treatment protocol and preparation within the apex more influential factors than the type of sealer used for the success of treatment outcome. This assessment utilized the VAS due to its subjective nature and the importance of self-evaluation.[13] Similar results showed in a systematic review by Monteiro et al. (2022)[14] and Mahajan et al.[15] stated no significant difference in postoperative discomfort levels between the sealers. However, a contradictory and inconsistent finding was reported by an in vivo study conducted by Paz et al., which stated that patients who received single-cone gutta-percha obturation using BCSs reported more postoperative pain compared to those treated with epoxy RBSs.[16]

In addition, the literature lacks studies on postoperative pain and periapical healing specifically in posterior teeth using different endodontic sealers. Therefore, our study included both anterior and posterior teeth to evaluate the efficiency of various sealers. Furthermore, there is a paucity of research on large periapical lesions in both anterior and posterior teeth and the influence of sealers on periapical healing. However, a systemic review conducted by Khandelwal et al. concluded that BCSs demonstrated superior results on periapical healing.[17] In current study suggests a reduction in the size of periapical lesions across all treatment groups postprocedure compared to preoperative levels. No studies to date have evaluated the postoperative pain and periapical healing of teeth that failed previous endodontic treatment and required retreatment. A systemic review by Shaik et al., aimed at estimating the impact of various endodontic sealers in endodontic treatment failure cases, specifically comparing BCSs with RBSs. The outcomes denote positive. In conclusion, BCSs demonstrated comparable interpretation compared to RBSs concerning the occurrence and intensity of pain.[18] Within the limitations of the current study, we evaluated periapical healing in both anterior and posterior teeth and endodontic retreatment cases using different endodontic sealers. We concluded that there were no significant discrepancies among the groups. In addition, follow-up radiographs at 3 months and 6 months showed a reduction in the size of periapical lesions and success of retreatment cases.

However, AH Plus sealer can lead to acute inflammation if the unset resin is extruded beyond the apex. Direct contact between periapical tissues and unset RBS paste can induce acute inflammation, discomfort, and irritation. In addition, there have been occasional reports of both local and systemic allergies associated with these sealers.[19] This was supported by clinical observations where some patients experienced postoperative pain due to sealer extrusion, although these symptoms resolved over time for most cases. Shashirekha et al. (2018) conducted a study to assess pain intensity following apical extrusion of RBSs and calcium hydroxide-based sealers. In some instances, both types of sealers led to posttreatment pain. However, neither type of sealer influenced the treatment outcome.[20] Current epoxy RBSs suffer from suggestive drawbacks such as leakage, cytotoxicity, and prolonged setting times.[21] The manufacturer specifies an 8 h setting time for the AH Plus sealer.[22] Furthermore, impaired dimensional stability due to polymerization shrinkage, with AH Plus showing a shrinkage of 1.76% of the total volume. Despite this, AH Plus maintains long-term dimensional stability owing to its low linear expansion and moderate shrinkage. Whereas in the current study, few patients underwent apical sealer puff unintentionally to further assess for any potential irritation or pain. Analysis indicated no statistically suggestive discrepancy in frequencies among the groups, with a P = 0.634 (P > 0.05) whereas minor irritation and pain were reported in the AH Plus sealer group when extruded beyond the apex which resolved with time. Extruded sealers may or may not persist on follow-up radiographs, but their impact on treatment outcomes appears minimal. A similar result was concluded in another study conducted by Martins J. F. B et al. (2023), to study the impact of AH Plus sealer puff on the outcomes of root canal treatment and retreatment in teeth with AP, in comparison with the teeth-filled AP but no sealer puff, at 1-year follow-up. Results indicated that accidental AH Plus sealer puff did not impede the healing of AP. However, it was distinguished that original endodontic therapy led to superior recovery of AP compared to retreatment in cases with AH Plus sealer puff. In addition, the distinguished prediction of the results was found to not affect treatment outcomes.[23]

Moreover, the recent introduction of Meta CeraSeal sealers to the market has led to a scarcity of studies evaluating their effectiveness in this context. There is a significant gap in the literature regarding the influence of CeraSeal sealers on the healing of periapical pathology and their role in addressing endodontic treatment failures. Despite this, CeraSeal sealers offer several practical benefits: They are available in syringe form, eliminating the need for mixing, and can be easily applied into the canal using a flexible long syringe tip. This design allows the sealer to flow effortlessly into accessory canals or curvatures due to its excellent flow properties, effectively sealing the dentinal tubules. In addition, CeraSeal sealers exhibit good radiopacity, providing clear visualization for proper obturation in radiographs. Their wettability enables them to set easily within the canal even in the presence of blood or other fluids. Patients typically experience minimal postoperative pain with CeraSeal sealers, and follow-up cases have indicated faster healing. Even when there is sealer extrusion beyond the apex, patients reported no discomfort postobturation, and this absence of discomfort continued during follow-up visits.

However, the current study has certain limitations. The VAS is constrained by its reliance on subjective pain perception. Implementing a split-mouth design in clinical trials can help mitigate this limitation. The use of periapical radiographs, which provide two-dimensional images of three-dimensional bony defects, may not be as precise as cone-beam computed tomography for evaluation. The periapical index, originally designed for upper anterior teeth, may not accurately reflect conditions in multi-rooted teeth or those with diverse morphologies and bone densities, potentially introducing bias. In addition, it does not account for the relationship between the root/periapical lesion and surrounding anatomical structures, making Periapical index radiographic assessments prone to observer bias and potentially inaccurate for evaluating periapical lesions in posterior teeth. However, a need to conduct controlled randomized clinical trials with a long duration of follow-up in the future to justify the following result.

CONCLUSIONS

Within the limitations of this study, which involved no analgesic use or intracanal dressing, all groups experienced a reduction in postoperative pain at both 24 and 48 h. However, by the 7^th day, there were no significant differences in pain levels among the groups. Both the control and intervention groups showed a decrease in the size of periapical lesions, as observed in follow-up radiographs. The study found no significant differences in periapical healing among the eugenol, resin, and bioceramic-based sealers.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.