Post-Operative Pain and Its Relationship with Patient-Related Factors after Vital Pulpotomy in Teeth with Symptomatic Pulpitis: A Prospective Clinical Study Open Access

Postoperative pain in endodontic treatment occurs in 1.4–50% of cases [1]. It significantly compromises patients’ quality of life, shapes their subjective evaluation of treatment options, and undermines the patient-clinician relationship [2]. The intensity of preoperative pain and severity of pulpal inflammation are key predictors of postoperative discomfort [3]. In cases of irreversible pulpitis, while the primary goal of nonsurgical endodontic treatment is to alleviate preoperative symptoms with minimal discomfort, it is important to acknowledge that the mechanical and chemical factors involved in the procedure may also contribute to postoperative symptoms [4].

In conventional practice, carious pulp exposure is considered a sign of irreversible pulpitis, leading to root canal treatment (RCT) when clinical symptoms such as spontaneous or lingering thermal pain are present [5]. However, clinical pain alone is not a reliable indicator of the extent of pulp damage, and studies have shown that in vital teeth, inflammation or necrosis rarely extends beyond the coronal pulp [6]. Nevertheless, research using calcium hydroxide for pulp capping in carious pulp exposure, which is associated with worsening and adverse long-term outcomes, has significantly influenced the recommendation for total pulpectomy (RCT) [7]. Although effective, RCT is a technically complex and time-consuming procedure [8] associated with structural weakening [9] and postoperative pain due to debris extrusion or inter-appointment flare-ups [4] which can cause patient anxiety [10].

In recent decades, attention has shifted toward vital pulpotomy therapy (VPT) as a minimally invasive option, even in cases of symptomatic irreversible pulpitis [6]. With increasing evidence that inflamed pulp retains regenerative capacity [11], VPT using bioactive materials such as calcium silicate cement has yielded promising outcomes, preserving pulp vitality and periapical health in cases that would traditionally receive RCT [12].

The introduction of mineral trioxide aggregate (MTA), a calcium silicate cement with superior resistance to leakage [13] and superior long-term success in vital pulp treatments compared with calcium hydroxide [14], has led to vital pulp treatment becoming a predictable and cost-effective treatment option that is less technically demanding than the RCT [15]. Long-term data further support its use, with high success and survival rates reported in mature teeth [16] and promotion of continued root development in immature teeth [17].

Unlike previous studies that primarily focused on treatment success or general pain incidence, the present study specifically investigated short-term postoperative pain in relation to patient-related factors, such as age, sex, and analgesic use. Although VPT has been supported in the literature [18], the relationship between postoperative pain and the factors mentioned above remains unclear. Therefore, this study aimed to quantify pain levels at multiple time points before and after treatment and to determine whether these factors influence the pain perception. The null hypothesis was that postoperative pain 1 week after VPT would not significantly differ from the preoperative levels.

As this was a prospective single-arm clinical trial involving clinical intervention in human subjects, ethical approval was obtained from the Institutional Review Board before the trial commenced. This study was conducted in accordance with the Code of Ethics of the World Medical Association and Declaration of Helsinki. This clinical trial was registered before patient enrollment. This clinical study was conducted according to the Preferred Reporting Items for Randomized Trials in Endodontics (PRIRATE) 2020 guidelines [19].

The minimum sample size was determined using G*Power 3.1.9.2, based on an effect size (dz = 0.3232) calculated from a previous study by Esteve-Pardo et al. [20], which reported pain scores of 2.0 ± 2.3 and 1.3 ± 2.0 in a similar clinical context. Assuming a significance level of 0.05 and power of 0.80, the required sample size was calculated as 78. A total of 108 participants were included in this study to ensure sufficient statistical power.

The study participants were recruited from a pool of patients who reported treatment in the postgraduate section of the endodontics and pediatric department of the university between December 2021 and December 2022. Six hundred participants were screened for inclusion, and patients were recruited based on the established inclusion and exclusion criteria.

The patients’ group included individuals with a molar tooth with a vital pulp (detected by clinical signs or symptoms) and a history of pain or symptoms classically indicative of irreversible pulpitis according to the American Association of Endodontists diagnostic terminology [21]. Specifically, the pain was spontaneous or exacerbated by cold stimuli, lasted for a few seconds to several hours (interpreted as lingering pain) compared with control teeth, and could be reproduced using cold testing.

The following inclusion criteria were used: age between 7 and 70 years, presence of permanent first and second molars with vital pulp, diagnosis of irreversible symptomatic pulpitis and periapical index of  ≤2 [22] with vital pulp, and the ability to cooperate with treatment. The exclusion criteria were as follows: lack of clinical or radiographic evidence of pulp vitality; presence of sinus tracts, swelling, or abnormal tooth mobility; signs of necrosis or periapical pathology on radiographs; root fractures; teeth with insufficient coronal structure requiring a post; systemic contraindications to treatment; pregnancy or lactation; recent use (within the past 7 days) of antibiotics, corticosteroids, bisphosphonates, or analgesics other than NSAIDs; and patients requiring endodontic treatment in multiple teeth. Young patients who were unable to provide reliable descriptions of their pain were also excluded to minimize the misinterpretation of symptoms.

Eligible participants, along with the parents of participants aged <18 years, provided informed consent before treatment. Participation was voluntary and the subjects could withdraw at any time. After applying the exclusion criteria, 114 patients were included in this study, as shown in Figure 1.

This was a prospective single-arm clinical trial without group allocation; thus, treatment randomization was not applicable. However, randomization was implemented for the timing and administration of pain assessment forms, using sealed envelopes prepared by an independent individual. Operators could not be blinded due to the standardized treatment protocol, but a blinded statistician performed outcome assessment. Further details on the randomization protocol, blinding strategy, and calibration procedures are provided in online supplementary Material 1 (for all online suppl. material, see https://doi.org/10.1159/000546582).

Clinicians (authors 1 and 2) were trained using a modified verbal descriptor scale (VDS). Prior to the study, both operators independently evaluated a set of standardized clinical cases to ensure consistency in pain scoring using the VDS. Inter-operator reliability was assessed using Cohen’s kappa statistic, yielding a value of 0.81, indicating almost perfect agreement. Before the treatment procedure, preoperative pain scores were recorded using the VDS [23]. Patients and parents were given detailed information and were asked to rate their pain using the following scale: 0 = no pain; 1 = mild pain, defined as feeling pain but not requiring analgesic intake; 2 = moderate pain, defined as feeling pain and requiring analgesic intake; and 3 = severe pain, defined as feeling pain and inability to perform any type of activity, feeling the need to lie down and rest, and experiencing little to no pain relief from analgesics. Analgesic need was used as an anchor in the VDS (i.e., pain that did or did not require medication), providing a more objective framework for assessment across age groups. When discrepancies occurred between the child and parents’ responses, the child’s self-reported pain score was prioritized.

Periapical radiographs were obtained during the initial diagnostic appointment prior to the treatment session per the routine clinical workflow of the institution. Eligibility based on the periapical index and other inclusion criteria was assessed before proceeding to the operative phase of treatment.

A standardized vital pulpotomy protocol was applied by two calibrated operators. Local anesthesia, caries removal, access preparation, pulpotomy, MTA application, and final restoration were performed per standard guidelines. Full clinical procedure details, including anesthesia protocol and restorative approach, are available in online supplementary Material 1.

The patients were informed of the potential for postoperative pain. Each patient was contacted by telephone by one of the two researchers 24 h, 72 h, and 1 week post-treatment to assess pain using the VDS. For blinding purposes, the researcher who did not perform the treatment conducted the follow-up calls.

Age groups were established according to World Health Organization age group standards [24]. All participants responded to the postoperative pain questionnaire. Therefore, the study was completed without dropout. Descriptive statistics are presented as numbers and percentages. For cases in which the assumption of sample size was not met (expected value <5), Fisher’s exact test was applied to test the relationship between categorical variables. Statistical analyses were conducted using IBM SPSS 25 (p < 0.05).

This section presents the demographic characteristics of the participants and evaluates postoperative pain outcomes and their relationship with patient-related factors, such as age, sex, and analgesic intake. The recall rate was 100%. Among the 114 patients, 110 (96.49%) had complete relief from preoperative pain after treatment, and no postoperative pain was recorded at 1 week, irrespective of patient-related factors such as age, sex, and painkiller intake. All tables referenced below can be found in the online supplementary Material 2.

A total of 114 patients (58 female and 56 male; age range, 7–39 years) were included in this study. All patients identified their sex as the same as their biological sex. The average age was 21.7 years (standard deviation: 8.27). All patients responded to the pain questionnaire; therefore, the study was completed without any missing data. All treatments were clinically controlled, with follow-ups at 6 months and 1 year. Four patients were referred for RCT because of continuous spontaneous pain 1 week after vital pulpotomy. No additional adverse events or clinical failures were observed during the short-term follow-up.

Online supplementary Table 1 presents the pain status reported by the patients before treatment and at 24 h, 72 h, and 1 week after treatment. Fisher’s exact tests were conducted to investigate the relationship between the patients’ pain status before treatment and at 24 h, 72 h, and 1 week after treatment. The analysis showed a statistically significant relationship between pain status before treatment and 24 h after treatment (p < 0.05). A closer examination of the scores revealed that the pain score was mostly 0 at 24 h when the pain score before treatment was 1 or 2, and it was mostly 1 at 24 h when the pain score before treatment was 2 or 3. No significant relationships were found between preoperative pain and pain at 72 h or 1 week (p > 0.05). Patients with initial scores of 1–3 reported pain scores of 0 at these later time points. Pain prevalence over time is shown in Figure 2.

Pain scores by analgesic intake are shown in online supplementary Table 2. Fisher’s exact tests showed no significant relationship between changes in pain status at 24 h, 72 h, and 1 week and the use of painkillers (p > 0.05). Although pain in general, decreased among those using analgesics, this decrease was not statistically significant at any time point.

Pain scores categorized by sex are shown in online supplementary Table 3. Fisher’s exact tests were conducted to investigate the relationships between changes in pain status at 24 h, 72 h, and 1 week after treatment, based on the patients’ pain status before treatment and their sex. The analysis revealed no statistically significant relationships between changes in pain status at 24 h, 72 h, and 1 week, and patient sex (p > 0.05).

The pain scores categorized by age group are shown in online supplementary Table 4. Fisher’s exact test was used to examine the relationships between changes in pain status at 24 h, 72 h, and 1 week after treatment based on the patients’ pain status before treatment and their age group. This analysis revealed no statistically significant relationships between changes in pain status at 24 h, 72 h, and 1 week and age (p > 0.05). When there was no change in pain status at 24 h, 72 h, and 1 week, patients were mostly in the 17–30 years age group; however, age did not have a statistically significant effect on the change in pain scores at 24 h, 72 h, and 1 week later.

Pain is the most important factor driving patients to seek dental treatment. In the current study, all participants had teeth that were initially symptomatic, with severe spontaneous or lingering pain. Among the 114 patients, preoperative pain was completely relieved after treatment in 110 (96.49%) cases, and no postoperative pain was recorded at 1 week, irrespective of patient-related factors such as age, sex, and painkiller intake. Therefore, the null hypothesis is rejected. Our results agree with previous reports of 85% [25] and 88.3% [26] total pain reduction after pulpotomy compared with preoperative pain values.

The efficacy of VPT for pain reduction can be explained by two mechanisms. First, it is well known that large nerve bundles comprising myelinated and non-myelinated axons are present in the radicular pulp. They become extensively branched at the Raschkow plexus, an area within the coronal pulp where the nerve fibers responsible for pain are concentrated. The nerve endings then pass through a layer of odontoblasts to reach the surrounding predentin/dentin region [27]. VPT involves removing the coronal pulp tissue to eliminate the source of inflammation and pain [6]. This removal includes the plexus, which could explain the effectiveness of VPT in reducing the pain symptoms associated with pulpitis.

Second, severe pain in irreversible pulpitis arises from inflammation of the vital pulp rather than from necrosis. In this study, controlled bleeding from root orifices confirmed the removal of infected pulp. The application of MTA to the remaining healthy radicular pulp likely relieved pain through its antibacterial, anti-inflammatory effects and sealing ability, reducing local pressure and inflammation. Histological studies support this healing mechanism by demonstrating dentin bridge formation over healthy pulp tissue after pulpotomy, which differs from RCT and explains the healing process [28]. Detailed analysis of findings in the context of previous research was provided in online supplementary Material 3.

Pulpotomy is generally considered technically simpler, less time-consuming, and more cost-effective than pulpectomy or root canal treatment [29]. In our study, postoperative symptoms persisted in 4 of 114 patients following VPT, necessitating subsequent RCT. Although existing evidence indicates that pulpotomy and root canal treatment offer comparable success rates for mature molars with carious pulp exposure, the long-term outcomes of VPT are influenced by both preoperative and intraoperative factors [30]. These include patient-related variables, such as age, sex, general medical condition, tooth type, stage of root development, lesion depth, type of pulp exposure, pulpal diagnosis and symptom severity, and the presence of periapical radiolucency. The current study specifically focused on the influence of certain patient-related factors on postoperative pain after pulpotomy. Detailed explanation and discussion of post-operative pain findings in the context of patient-related factors were provided in online supplementary Material 3, under Factors influencing the success of VPT subheading.

The detailed discussion of the methodology regarding local anesthesia, VPT protocol, and the pain assessment methods is provided in online supplementary Material 3, under Evaluation of the Methodology subheading.

This study has several strengths as it is among the few recent clinical investigations focusing on postoperative pain following VPT in teeth diagnosed with symptomatic irreversible pulpitis. These findings contribute to the growing body of evidence supporting VPT as a viable alternative treatment in such cases. Furthermore, few studies have examined the potential relationship between postoperative pain and patient-related factors, making this investigation particularly relevant. Importantly, the study achieved a 100% recall rate, which enhanced the strength of the clinical evidence.

This study has several limitations. Operator blinding was not feasible due to the standardized treatment approach; however, an independent, blinded evaluator performed an outcome assessment to reduce bias. Postoperative pain following VPT and RCT could not be compared within the same cohort, and the short (1-week) follow-up period did not permit evaluation of long-term outcomes. This limitation aligns with recent evidence from a meta-analysis that could only include two clinical trials and concluded that current data are insufficient to draw robust conclusions regarding long-term outcomes and comparative pain levels of VPT versus RCT [31].

Another limitation is we did not evaluate caries depth or type of pulp exposure; while deep caries may compromise pulpal status and reduce success, previous studies suggest that the type of exposure (mechanical vs. carious) does not significantly impact outcomes when clinical protocols are properly followed [30]. As our study focused exclusively on patient-related, non-clinical factors, future studies should explore the impact of caries depth and exposure type on postoperative pain outcomes.

Based on the findings of the present study, vital pulpotomy appears to be an effective treatment option for symptomatic pulpitis, providing significant relief from pulpal pain, without additional postoperative discomfort. These outcomes were independent of patient-related factors, such as age, sex, and preoperative analgesic use. In real-world clinical settings, vital pulpotomy offers notable advantages, in terms of feasibility and accessibility. Compared to root canal treatment, VPT involves a shorter chairside time, fewer procedural steps, and reduced equipment requirements, making it particularly suitable for broader implementation, especially in resource-limited environments. Furthermore, the present study found that postoperative pain outcomes were not significantly influenced by patient-related factors, such as age, sex, or analgesic intake. This suggests that once the indication is correctly established, VPT may be predictably applied across diverse patient populations, with minimal influence from individual variability. Clinicians may, therefore, consider VPT a viable alternative for managing pulpal pain in appropriately selected cases.

Our study demonstrated that vital pulpotomy effectively reduces preoperative pain and does not induce postoperative pain in irreversible symptomatic pulpitis, regardless of patient-related factors. As a technically simple, cost-effective, and well-tolerated procedure, it offers a promising alternative to root canal therapy, particularly in resource-limited settings or when immediate pain relief is needed. However, the lack of a comparison group and short follow-up limit the assessment of long-term outcomes; thus, further studies with longer follow-up and direct comparisons to root canal treatment are warranted. Clinicians may consider vital pulpotomy as an alternative to root canal therapy for vital teeth with irreversible symptomatic pulpitis.

This study was approved by the Medical Ethics Committee of Usak University (180-180-13). Written informed consent was obtained from all adult patients and from the parents or legal guardians of patients under eighteen who volunteered to participate in this study. This clinical trial was registered on clinicaltrials.gov.tr before patient enrollment with the ID number NCT0621695.

The authors declare no conflicts of interest.

This study was not supported by any sponsors or funding.

Berk Çelikkol: conceptualization, methodology, validation, investigation, and writing – review and editing. Hasibe Elif Kuru: conceptualization, methodology, validation, investigation, data curation, writing – original draft, editing, and visualization.

Data supporting the findings of this study are available upon request from the corresponding author.