This Phase IV randomized clinical trial (RCT) evaluated the efficacy of preoperative administration of a single 4 mg oral dose of dexamethasone in reducing postoperative pain and inflammation following endodontic treatment. Conducted at the Department of Endodontics, PhD Program, Faculty of Dentistry, University of Salamanca, the study included 82 participants who were randomly assigned to either the test group (preoperative dexamethasone) or the control group (postoperative ibuprofen 400 mg every 4 hours).

Pain intensity was measured using the Visual Analog Scale (VAS) at 4, 6, 8, 12, and 24 hours postoperatively. Results indicated significantly lower pain perception in the dexamethasone group compared to the ibuprofen group at all time points, with the majority of dexamethasone-treated patients reporting only mild pain. No adverse effects were observed in either group, and no patient required additional rescue analgesia.

The findings suggest that a single preoperative dose of dexamethasone is a safe and effective strategy for managing postoperative pain in endodontic procedures, providing superior analgesia compared to the standard postoperative ibuprofen regimen.

Keywords: Endodontic pain, dexamethasone, preoperative analgesia, randomized clinical trial, inflammation control, corticosteroids, endodontics.

Background and Rationale:

Endodontic treatment is a standard dental procedure aimed at preserving teeth with irreversible pulp damage or infection. A common complication following such procedures is postoperative pain and inflammation, typically managed with nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen. However, corticosteroids like dexamethasone, known for their potent anti-inflammatory and analgesic properties, may offer an alternative approach.

Dexamethasone is a long-acting glucocorticoid that inhibits phospholipase A2, thereby reducing the production of prostaglandins and leukotrienes-key mediators in the inflammatory cascade. This mechanism potentially prevents peripheral sensitization and hyperalgesia, which are central to post-endodontic pain. While dexamethasone has shown efficacy in oral surgery, its use as a preoperative analgesic in endodontics remains under-investigated.

Study Objectives:

The primary objective is to evaluate whether a single 4 mg oral dose of dexamethasone administered preoperatively reduces postoperative pain following endodontic treatment. Secondary objectives include assessing the need for rescue analgesia and monitoring for adverse effects.

Study Design:

This is a Phase IV randomized clinical trial using a parallel assignment model with a 1:1 allocation ratio. The study was conducted at the Faculty of Dentistry, University of Salamanca.

Participants and Randomization:

A total of 82 adult patients (aged 20-50) requiring endodontic intervention were enrolled. Participants were randomized into two groups:

Dexamethasone Group (Experimental): Received 4 mg dexamethasone orally 1 hour prior to the procedure.

Ibuprofen Group (Active Comparator): Received no preoperative medication but were prescribed 400 mg ibuprofen every 4 hours postoperatively.

Blinding:

The study was single-blind; participants were unaware of their group allocation.

Intervention:

All patients underwent standardized endodontic treatment involving local anesthesia, rubber dam isolation, mechanical root canal instrumentation using rotary systems, and irrigation with sodium hypochlorite. Root canal obturation followed standard protocols using gutta-percha and resin-based sealers.

Outcome Assessment:

Pain intensity will be measured using the Visual Analog Scale (VAS) at 4, 6, 8, 12, and 24 hours postoperatively. Secondary outcomes include the number of participants requiring rescue analgesia and any adverse effects reported during the first 24 hours.

Statistical Analysis:

Data will be analyzed using SPSS version 22.0. The normality of continuous variables will be assessed using the Shapiro-Wilk test. Pain intensity scores will be compared using ANOVA with Tukey post-hoc tests for multiple comparisons. A p-value < 0.05 will be considered statistically significant

Inclusion Criteria:

• Participants must meet all of the following criteria to be eligible for the study:
• Age Range: 20 to 50 years old.
• Indication for Endodontic Treatment: Patients requiring root canal therapy due to irreversible pulpitis (with or without apical lesion), pulp necrosis, retreatment with periapical lesion, or endodontic surgery.
• Eligible Teeth: Any dental group (anterior, premolar, molar, both maxillary and mandibular).
• General Health Status: Classified as ASA I (healthy individuals without systemic conditions) according to the American Society of Anesthesiologists (ASA) Physical Status Classification.
• Consent: Willingness to participate in the study and ability to provide signed informed consent.

Exclusion Criteria:

• Participants will be excluded if any of the following conditions apply:
• Age: Under 20 or over 50 years old.
• Medical Conditions:

Immunocompromised individuals (e.g., HIV/AIDS, cancer patients undergoing chemotherapy).

Systemic diseases such as diabetes mellitus, osteoporosis, acute psychosis, glaucoma, cataracts.

Patients with tuberculosis or systemic fungal infections. Gastrointestinal conditions such as ulcerative colitis, peptic ulcers, or diverticulitis.

-Medication Use: Use of NSAIDs or corticosteroids within 48 hours prior to the intervention. Regular use of barbiturates.

-Dental Factors: Tooth fractures involving the roots. Severe dental hypersensitivity that may interfere with pain assessment.

-Pregnancy and Lactation: Pregnant or breastfeeding women will be excluded due to potential effects of dexamethasone.

-Non-Compliance: Patients who decline participation or are unwilling to follow study procedures, including pain assessment and follow-up.

The study does not plan to share individual participant data (IPD) due to patient confidentiality and ethical considerations. Only aggregated, anonymized data will be presented in publications and reports.