The effect of different concentrations and temperatures of sodium hypochlorite irrigation on pain intensity following endodontic treatment of mandibular molars with irreversible pulpitis: A randomized, double‐blind clinical trial

Abstract

ObjectivesThis study aimed to determine the severity of pain after endodontic treatment of mandibular molars with irreversible pulpitis following the use of sodium hypochlorite (NaOCl) at different temperatures and concentrations.MethodsIn this randomized, controlled clinical trial, 72 patients with mandibular molars with irreversible pulpitis were randomly assigned to six groups. The teeth were anesthetized and the root canals were prepared. During the instrumentation, the root canals were irrigated with NaOCl solution at concentrations of 0.5% and 1% and temperatures of 2.5°C, 22°C, and 40°C, 2.5°C were achieved through cryotherapy. Assessment of pain was conducted before, immediately after, and 3, 24, 48, and 72 h after treatment. After obturation, the patients recorded their pain intensity at different time intervals on the visual analog scale (VAS) and reported the number of analgesics tablets they used. The frequency of analgesics tablets and their effect on pain sensation was recorded in the second part of the form. Repeated measures two‐way analysis of variance test was used to compare the trend of pain changes over time between two intervals of time in each group. Friedman's nonparametric test was used to compare the intragroup mean score of pain over time and Kruskal–Wallis for comparing the intergroup mean score.ResultsChanges in VAS pain scores of all the groups were significant over time (p < .001). Pain in all the groups decreased immediately after treatment and increased 3 h after treatment. There were no significant differences in pain ratings and the number of analgesics tablets used in the groups of NaOCl with different concentrations and temperatures over time.ConclusionsWithin the study's limitations, we concluded that there was no significant difference between concentrations of 0.5%, and 1% and temperatures of 2.5°C, 22°C, and 40°C in pain intensity following endodontic treatment of mandibular molars with irreversible pulpitis.

Evaluation of the Impact of Different Instrumentation Techniques on the Incidence of Postoperative Pain in Patients Undergoing Root Canal Treatment

“…At the six-hour time interval, the step-back preparation technique had 15% of patients reporting no pain (1 on the pain scale), 30% experiencing mild pain (2), 25% with moderate pain (3), 15% with severe pain (4), and 10% with very severe pain (5). The crown-down preparation, hybrid technique, and conventional instrumentation showed similar patterns of pain responses, with slightly varying percentages.…”

“…At the 24-hour time interval, the percentage distribution of pain responses further shifted. The step-back preparation had 28% of patients reporting no pain (1), 25% with mild pain (2), 18% with moderate pain (3), 15% with severe pain (4), and 14% with very severe pain (5). The crown-down preparation, hybrid technique, and conventional instrumentation exhibited comparable patterns with slight variations in the…”

“…Various instrumentation techniques are employed in root canal treatment, each with its own advantages and disadvantages [4]. The step-back preparation technique involves a sequential increase in instrument size to gradually shape the canal, while the crown-down preparation technique focuses on creating a wider coronal portion before progressing apically [5]. The hybrid technique combines elements of both step-back and crown-down techniques to benefit from their individual advantages [6].…”

Endodontic irrigants from a comprehensive perspective

“…It is worth mentioning that the NaOCl concentration has effect on its efficacy, in which lower concentrations (0.5%-1%) are indicated in biopulpectomy and pulpotomy; however, higher concentrations (2.5% and higher) are indicated for necropulpectomy as in periapical periodontitis and periapical abscess[ 30 , 31 ]. These indications are highly attributed to its antimicrobial, anti-endotoxin, and organic tissue capacity, in addition to its biocompatibility[ 4 , 5 , 10 ], in which lower concentrations are safer for tissues and have a lower risk of irritation or chemical burns but are less effective in dissolving organic matter, and require a longer exposure time[ 32 ].…”