Effect of bioceramic-based and resin-based sealers on postoperative discomfort following root canal therapy: a systematic review and meta-analysis

Introduction

Root canal therapy (RCT) is the principal approach to treating root canal infections (Gulabivala & Ng, 2023). The selection of disinfection procedures and obturation materials may play a crucial role in ensuring treatment efficacy and minimizing complications (Silva et al., 2022). Postoperative discomfort is a commonly reported complication among patients after dental procedures, including root canal therapy (Thakur et al., 2023). Physical trauma during treatment, inflammation, and bacterial extrusion are common causes of postoperative discomfort. Iatrogenic causes such as, the selection of instruments and working length or the root canal sealer, may also contribute to postoperative discomfort (Pawar et al., 2022).

The Likert-type scale is a widely recognized and invaluable instrument used to quantify pain and discomfort experienced by patients after endodontic treatment (Santos-Puerta & Peñacoba Puente, 2022). It consists of two different scales, namely the Visual Analog Scale (VAS) and the Four-Point Pain Scale (Delgado et al., 2018). While using the VAS requires patients to mark the intensity of their pain through a line, the Four-Point Pain Scale provides four different rates for the patient to choose their pain level (Atisook et al., 2021). The reliability and efficacy of both scales in evaluating postoperative pain are two vital indicators for healthcare professionals to determine the appropriate course of treatment and manage patient expectations (Mahama & Ninnoni, 2019). Consequently, the use of Likert-type scales has been an increasingly accepted practice in endodontic therapy and other medical fields. The choice of obturation technique can significantly influence postoperative pain and discomfort, with the cold lateral compaction technique being the most effective in minimizing these issues (Wong et al., 2017).

Several studies have investigated the relationship between root canal sealers and postoperative pain with various results (Ferreira de et al., 2020a; Shim, Jang & Kim, 2021; Monteiro et al., 2023; Coşar, Kandemir Demirci & Çalışkan, 2023). Evidence suggests that specific types of sealers, like resin-based sealers, might be linked to higher levels of postoperative discomfort compared to other sealers, such as zinc oxide eugenol-based sealers (Özdemir & Kopac, 2022). The composition of the root canal sealers may play a key role in managing postoperative pain and discomfort. Bioceramic root canal sealers (BCS) have garnered considerable attention in recent years due to their remarkable sealing ability and biocompatibility. BCS synergistically create a highly bioactive and biocompatible substance by combining calcium silicates, monobasic calcium phosphate, zirconium oxide, filler particles, and a hydrophilic polymer. These components actively support tissue regeneration and effectively inhibit the growth of bacteria, fostering a conducive environment for optimal healing. Numerous studies have demonstrated that BCS can significantly reduce postoperative pain in root canal therapy by inhibiting bacterial growth and promoting tissue healing (Mekhdieva et al., 2021). Compared to patients treated with traditional zinc oxide eugenol-based or resin-based root canal sealers, patients treated with BCS experienced much less postoperative pain. Resin-based sealers have been shown to produce residual monomers and cause cytotoxicity, which can be uncomfortable even when they show good biocompatibility (Javidi et al., 2020). These sealers consist of a combination of resin monomers, fillers such as quartz, silica, glass particles, and zirconium oxide, with additional additives to impart the necessary chemical and physical characteristics (Cho et al., 2022). In some circumstances, resin-based sealers might be suitable, especially if a patient is allergic to any of the chemicals in other kinds of sealers (Syed, Chopra & Sachdev, 2015). Resin sealers can be used to avoid triggering allergic reactions in such cases. Additionally, resin-based sealers are more effective in sealing off microcracks and fissures in the root canal system.

From the root canal issue highlighted, this systematic review and meta-analysis of relevant clinical studies aim to assess and compare the effects of bioceramic-based and resin-based root canal sealers in alleviating/preventing postoperative pain. The secondary aim was to evaluate the consumption of analgesics required to treat postoperative pain associated with the use of either bioceramic or resin-based sealers.

Survey Methodology

Results

The initial electronic database search yielded 6,461 titles from PubMed/MEDLINE, the Cochrane Library, DOAJ, Embase, SCOPUS and Google search. There were 638 duplicate articles. From the screening of the abstracts, two independent reviewers selected 254 relevant titles, and 5,666 were removed due to having an unrelated topic and publication year. Based on the reviewers’ decision, 19 articles were chosen for full-text evaluation. The manual search of the references from the selected studies yielded no matched articles. Following pre-screening, the articles were selected using inclusion and exclusion criteria. Then, based on the PICO questions, nine studies of the total search were included in the qualitative synthesis or data extraction. Meta-analysis of five selected studies was then conducted (Fig. 1).

Risk of bias applicability

The Cochrane Risk of Bias Tool (ROB-2) was used for evaluating the quality of randomized controlled trials (Table 4; Figs. 2 and 3). Four studies (Fonseca et al., 2019; Atav Ates et al., 2019; Ferreira de et al., 2020b; Khandelwal et al., 2022) exhibited a low risk of bias; two studies (Ferreira de et al., 2020c; Shim, Jang & Kim, 2021) showed a moderate risk; and three studies (Graunaite et al., 2018; Sharma et al., 2020; Khatri et al., 2022) displayed a high risk of bias. The absence of random sequence generation was not reported in three studies (Graunaite et al., 2018; Sharma et al., 2020; Khatri et al., 2022), contributing to the high risk of bias in these studies. All studies, except for Sharma et al.’s (2020) research, employed blinding techniques.

Table 4:

Risk of bias assessment.

Sr.No.	Author	Randomsequence generation	Allocation concealment	Blinding ofparticipants and personnel	Blinding ofoutcome assessment	Incomplete outcome data	Selective reporting	Other bias	Risk of bias
1	Atav Ates et al. (2019)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Low risk
2	Graunaite et al. (2018)	Unclear	No	Yes	Yes	Unclear	No	Unclear	High risk
3	Fonseca et al. (2019)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Low risk
4	Sharma et al. (2020)	No	No	Unclear	Unclear	Yes	Unclear	Yes	High risk
5	Ferreira de et al. (2020a); Ferreira de et al. (2020b)	Yes	Yes	Yes	Unclear	Unclear	Yes	Yes	Moderate risk
6	Tan et al. (2021)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Low risk
7	Shim, Jang & Kim (2021)	Yes	Yes	Yes	Yes	Unclear	Yes	Unclear	Moderate risk
8	Khandelwal et al. (2022)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Low risk
9	Khatri et al. (2022)	No	No	No	Unclear	Unclear	Yes	Unclear	High risk

DOI: 10.7717/peerj.18198/table-4

Six-hour post-operative pain level

Two studies (Atav Ates et al., 2019; Khatri et al., 2022) evaluated post-operative pain after six hours of treatment. The pooled mean difference was 0.30 [−0.21, 0.80] indicating that the mean pain scores were greater with resin-based sealers than with bioceramic sealers at six hours. Heterogeneity (I2) was 0%, and a fixed effect model was used. The results were not statistically significant (p > 0.05) (Fig. 4).

Twelve-hour post-operative pain level

Two studies (Atav Ates et al., 2019; Khatri et al., 2022) evaluated post-operative pain after 12 h of treatment. The pooled mean difference was 0.20 [−0.24, 0.64] indicating that mean pain scores were greater with resin-based sealers than with bioceramics sealers at 12 h. Heterogeneity (I2) was 0%, and a fixed effect model was used. The results were not statistically significant (p > 0.05) (Fig. 5).

Twenty-four-hour post-operative pain level

Five studies (Graunaite et al., 2018; Fonseca et al., 2019; Atav Ates et al., 2019; Khandelwal et al., 2022; Khatri et al., 2022) evaluated post-operative pain after 24 h of treatment. The pooled mean difference was 0.51 [0.16, 0.85] indicating that mean pain scores were greater with resin-based sealers than with bioceramics sealers at 24 h. Heterogeneity (I2) was 1%, and thus a fixed effect model was used. The results were not statistically significant (p > 0.05) (Fig. 6).

Forty-eight-hour post-operative pain level

Four studies (Graunaite et al., 2018; Fonseca et al., 2019; Khandelwal et al., 2022; Khatri et al., 2022) evaluated postoperative pain after 48 h of treatment. The pooled mean difference was −0.27 [−1.12, 0.58] indicating that mean pain scores were greater with bioceramics sealers than with resin-based sealers at 48 h. Heterogeneity (I2) was 59%, thereby using a random effect model. The results were not statistically significant (p > 0.05) (Fig. 7).

Analgesic use

Four studies (Graunaite et al., 2018; Fonseca et al., 2019; Atav Ates et al., 2019; Tan et al., 2021) evaluated analgesic use after 24 h of treatment. The pooled risk ratio indicated that the risk of analgesic use with resin-based sealer was 1.89-fold (RR = 1.89 [0.61, 5.81]) more than with bioceramics-based sealer at 24 h of treatment. Heterogeneity (I2) was 59%, thereby utilizing a random effect model. The results were not statistically significant (p > 0.05) (Fig. 8).

Discussion

The present investigation evaluated the effects of two root canal sealers on postoperative pain in single-visit endodontic treatment: resin-based sealers (RBS) and bioceramic-based sealers (BCS). Every study that was included completed the entire root canal procedure—including root canal preparation and obturation in a single visit. Endodontic procedures can induce patient anxiety, especially when complications and pain arise and thus exacerbate this anxiety (Peng et al., 2007; Alroomy et al., 2020). Severe pain after root canal treatment reflects intricate cellular-level physiological changes (Gotler, Bar-Gil & Ashkenazi, 2012). At the start of endodontic therapy, three potential outcomes that may occur include no symptoms, manageable pain/pressure, or intense pain/swelling which needs an unscheduled clinical visit (Bassam et al., 2021).

Post-operative endodontic pain often stems from local inflammatory responses in periapical tissue, with biochemical mediators such as reactive oxygen species (ROS) contributed to the discomfort (Georgiou et al., 2021). Root canal sealers, including bioceramic-based sealers (BCS) and resin-based sealers (RBS), can induce post-operative discomfort by releasing ROS and activating trigeminal nociceptors and pain-sensitive sensory receptors. This activation may lead to increased irritation and discomfort, possibly exacerbated by the release of calcitonin gene-related peptides (CGRP) via nociceptor stimulation (Graunaite et al., 2018; Jamali et al., 2021). Therefore, selecting the suitable sealer and applying it correctly is essential to minimize post-operative pain and discomfort.

This study focused on comparing the frequency of postoperative pain associated with two distinct types of root canal sealers: BCS and RBS. BCS, composed of biocompatible and bioactive inorganic materials, offers high sealing qualities, biocompatibility, and antibacterial activity. In contrast, RBS, made of organic components, may exhibit lower biocompatibility and antibacterial activity but its high pH that can neutralize the root canal’s acidic environment and benefit periapical tissues (Wang, 2015; Wang, Shen & Haapasalo, 2021). Notably, resin-based sealers like AH plus may release residual monomers, potentially triggering inflammation and discomfort, while BCS, with its biocompatible and bioactive inorganic materials, ensures a tight seal within the root canal, preventing bacterial entry and infection (Sanz et al., 2022; Torbati et al., 2023). Choosing a certain type of sealer may have a significant impact on postoperative patient comfort after endodontic procedures.

A meta-analysis was conducted to assess postoperative pain levels at specific intervals of 6, 12, 24, and 48 h following dental procedures. The importance of evaluating pain at these particular time points is that it can significantly impact a patient’s comfort, function, and overall quality of life. An accurate understanding of pain duration, intensity and these critical intervals can help clinicians develop effective pain management strategies, minimize patient discomfort and promote optimal healing (Choi et al., 2021).

Post-operative pain at six hours is a key indicator of immediate post-operative discomfort, while pain levels at 12 h signify the patient’s recovery (Garimella & Cellini, 2013). Two studies (Atav Ates et al., 2019; Khatri et al., 2022) compared post-operative pain in patients using resin-based and bioceramic-based sealers at six and 12 h of interval. The pooled mean difference was 0.30, suggesting slightly higher pain scores in resin-based sealers. However, with low heterogeneity (I2 = 0%) and a significance level (p = 0.25) greater than 0.05, the difference in pain scores between the two groups may not be substantial enough to cause different levels of pain.

Post-operative pain at 24 h is a crucial marker in a patient’s recovery. Five studies (Graunaite et al., 2018; Fonseca et al., 2019; Atav Ates et al., 2019; Khandelwal et al., 2022; Khatri et al., 2022) assessed post-operative pain levels at the 24-hour interval were consistent with those at 6 and 12 h. Resin-based sealers consistently showed slightly higher pain scores than bioceramic sealers. Importantly, the analysis found no statistically significant difference in pain scores between the two groups (resin-based and bioceramic root canal sealers) as indicated by the obtained p-value (p > 0.05).

Patients who have undergone root canal therapy could experience pain at 48 h of post operation, which could indicate delated pain or complications. The postoperative pain after 48 h of operation was assessed in four studies (Graunaite et al., 2018; Fonseca et al., 2019; Khandelwal et al., 2022; Khatri et al., 2022). The bioceramic sealers were consistently reported resulting slightly higher pain scores than resin-based sealers. However, based on the statistical analysis with a p-value greater than 0.05, it was determined that there was no statistically significant distinction between the resin-based and bioceramic root canal sealers.

The results showed that the analgesics were used in conjunction with root canal sealers to manage post-operative pain. A meta-analysis conducted examined the use of analgesics at 24 h after root canal therapy involving resin-based and bioceramic-based sealers. Data from four studies (Graunaite et al., 2018; Fonseca et al., 2019; Atav Ates et al., 2019; Tan et al., 2021) analyzed revealed that patients receiving resin-based sealers were 1.89 times more likely to require analgesics compared to those with bioceramic-based sealers. However, there was notable variability in the need of analgesics among the studies.

Two of the nine selected studies concluded that pain after the use of bioceramic sealers was lower than that after the use of resin-based sealers (Atav Ates et al., 2019; Khandelwal et al., 2022). The other seven studies (Graunaite et al., 2018; Fonseca et al., 2019; Ferreira de et al., 2020b; Sharma et al., 2020; Tan et al., 2021; Shim, Jang & Kim, 2021; Khatri et al., 2022) concluded that there was no difference between postoperative pain after the use of either bioceramic or resin-based sealers. The results align with the latter group of studies.

The different approaches and methods used by the included studies present one possible research constraint. This might add heterogeneity into the analysis and compromise the validity and generalizability of the findings. Furthermore, the potential for publication bias and the dependence on published research may have an effect on the overall results and distort the conclusions. The generalizability of the results may be further limited by variations in participant demographics and cultural characteristics, as well as in the definition and measurement of postoperative pain.

These limitations might be addressed by subgroup analyses to account for methodological variations. Sensitivity analysis and meta-regression are two further tools for managing heterogeneity. A thorough search approach that includes unpublished studies and grey literature, in addition to statistical measures like Egger’s test and funnel plots. It is essential to take cultural norms and healthcare systems into account when adapting conclusions to various populations and circumstances.

Conclusions

The pain levels for bioceramic sealers were less than resin-based sealers till 24 h post-operatively. However, after 48 h, the pain levels in the bioceramic group were greater than the resin-based sealers. The findings of this systematic review and meta-analysis suggest that postoperative pain levels with bioceramic sealers had no significant difference from those reported after the use of resin-based sealers.

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