Suzan Abdul Wanees Amin

Objectives: This study aimed to systematically review the pain and flare-up effects of calcium hydroxide (CH) as intracanal medication (ICM) in non-vital mature teeth.

Materials and Methods: Electronic-databases searching for published and grey literature and manual searching were conducted. Only randomized clinical trials (RCTs) were included comparing CH to other ICMs in non-vital mature teeth. The risk of bias was assessed using the RoB 2.0 Cochrane tool. The main outcomes were pain and flare-up. Qualitative and quantitative analysis, wherever applicable, was performed. The certainty of evidence (CoE) was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE).

Results: Sixteen articles were included in 6 comparisons at different time points for different outcomes. CH reduced pain risk than no ICM within the 1-14-days interval ( < 0.05) and than triple-antibiotic paste within the first day ( < 0.05) and was similar to corticosteroid/antibiotics combination ( > 0.05). Chlorhexidine (CHX) or CH/CHX, however, reduced pain levels than CH alone ( < 0.05). CH showed higher flare-up risk than CHX ( < 0.05). CoE, however, ranged from very low to moderate.

Conclusion: Most comparisons for different outcomes are based on very few studies, mostly low-powered, with an overall low CoE. Thus, the available evidence is considered insufficient to either support or refute CH effectiveness or to recommend one ICM over another. Therefore, further well-designed, larger RCTs are required.

Trial Registration: PROSPERO database Identifier: CRD42016041953.

INTRODUCTION: The aim of this prospective, randomized, double-blind clinical trial was to evaluate the effect of a preoperative, single, oral dose of diclofenac potassium (DFK) on postoperative pain and rescue analgesic intake in patients with symptomatic irreversible pulpitis in mandibular molars treated in 1 visit.

METHODS: Seventy emergency patients with moderate to severe preoperative pain randomly received either 50 mg DFK or placebo tablets 1 hour before starting endodontic treatment (n = 35 per group). Patients recorded their pain level 6, 12, 24, and 48 hours after treatment on a 170-mm Heft-Parker visual analog scale. The incidence of rescue analgesic intake was also recorded. Outcome data were statistically analyzed using Mann-Whitney U, Friedman, Wilcoxon signed rank, and chi-square tests. Binary logistic regression assessed the association of predisposing factors with postoperative pain. The significance level (α) was set at 0.05.

RESULTS: Of the 70 patients, 68 were analyzed (n = 34 per group). Both groups had similar baseline characteristics (P > .05). DFK showed significantly less pain incidence and intensity than the placebo at 48 hours only (P < .05). A significant decrease occurred from 24 to 48 hours with DFK (P < .05), which was not recorded with the placebo (P > .05). No difference in the incidence of rescue analgesic intake was reported between groups (P > .05). Food intake timing, sex, and rescue analgesic intake were associated with postoperative pain (P < .05).

CONCLUSIONS: Premedication by a single, oral dose of 50 mg DFK could be effective in reducing postendodontic pain at 48 hours after 1-visit endodontic treatment in mandibular molars with symptomatic irreversible pulpitis.

AIM: This randomized, prospective, controlled trial assessed the effect of occlusal reduction on post-treatment endodontic pain and medication intake following root canal treatment of mandibular posterior teeth with symptomatic irreversible pulpitis with sensitivity to percussion treated in two visits.

METHODOLOGY: Three hundred and eight patients were randomly assigned into two equal groups according to whether occlusal reduction was done or not (n = 154). For all patients, root canal treatment was carried out in two visits without intracanal medication. Patients assessed their pain using the 0-10 numerical rating scale (NRS) 6, 12, 24 and 48 h after the first visit (post-instrumentation) and 6 and 12 h following root canal filling (post-obturation). Patients, also, recorded their medication intake (sham or analgesic), post-instrumentation and post-obturation; patients initially received a sham capsule, but, if pain persisted, an analgesic was prescribed. Data were analysed using Mann-Whitney U-test, Friedman's test, Wilcoxon's rank test and chi-square (χ ) test. The relative risk (RR) and its 95% confidence interval (CI) were calculated for binary data.

RESULTS: Occlusal reduction was associated with lower pain intensity than no occlusal reduction at 12 and 24 h post-instrumentation (P < 0.05). Pain intensity significantly and gradually decreased with both groups at all post-instrumentation and post-obturation time-points compared to preoperative pain (P < 0.05). The RR of moderate-to-severe pain was 0.61 (95% CI: 0.41, 0.91) 12 h post-instrumentation, and the RR of pain incidence, regardless of its level, was 0.75 (95% CI: 0.61, 0.92) 24 h post-instrumentation. There was no significant difference in medication intake (sham or analgesic) between groups (P > 0.05).

CONCLUSIONS: Occlusal reduction was effective in reducing the intensity of postoperative pain 12 h and 24 h after root canal instrumentation in the first visit in patients with symptomatic irreversible pulpitis with sensitivity to percussion. Occlusal reduction lowered the risk of moderate-to-severe pain by about 40% 12 h post-instrumentation and the overall risk of pain by 25% 24 h post-instrumentation; yet, it did not affect medication intake.

AIM: This randomized, prospective, double-blind, clinical trial assessed the effect of 1.3% and 5.25% sodium hypochlorite (NaOCl) as irrigants on postendodontic pain and medication intake following root canal treatment of mandibular molars with non-vital pulps.

METHODOLOGY: Three hundred and eight patients, each with one symptomatic or asymptomatic molar, were randomly assigned, using the permuted-block method, into two equal groups according to NaOCl concentration: 1.3% or 5.25% (n=154). For both groups, syringe irrigation was performed using a 27-gauge needle advanced into the canal to a depth of 3mm from the working length; 3 mL were used between every 2 consecutive instruments. All root canal treatments were carried out in two visits, with no intracanal medication, by trained postgraduate students. The canals were prepared using the Protaper Universal rotary system during the first visit. In the second visit 7days later, the same irrigant per group was used and the canal walls were reprepared with the final instrument before filling the canal using the modified single-cone technique with an epoxy resin-based sealer. Patients assessed their postoperative pain using the 0-10 numerical rating scale (NRS) immediately after instrumentation, 3h, 24h, 48h and 7d after the first visit and immediately following root canal filling. The incidence of rescue-medication intake (Sham or analgesic) was, also, recorded; patients received a sham capsule to be used first, but, if pain persisted, an analgesic was prescribed. Outcome data were analysed using Mann-Whitney U-test, Friedman's test, Wilcoxon's rank test and Chi (χ ) test. Relative risk reduction (RRR) and its 95% confidence interval (CI) were calculated for binary data.

RESULTS: The incidence and intensity of postoperative pain was significantly lower with 1.3% NaOCl than 5.25% NaOCl at all timepoints (p<0.05). Postoperative-pain intensity exceeded preoperative pain at 3h and 24h with 5.25% NaOCl only (p<0.05). The relative risk reduction in pain incidence was 38% (95% CI: 17%, 54%) immediately after instrumentation, 41% (95% CI: 31%, 49%) at 3h, 42% (95% CI: 32%, 51%) at 24h, 59% (95% CI: 45%, 69%) at 48h, 62% (95% CI: 27%, 80%) at 7d and 81% (95% CI: 68%, 89%) post root filling. RRR was 38% (95% CI: 1%, 61%) for sham intake and 69% (95% CI: 37%, 85%) for analgesic intake.

CONCLUSIONS: Using 1.3% NaOCl was associated with less intense and less frequent postendodontic pain than 5.25% NaOCl in mandibular molars with non vital pulps treated in two visits. The incidence of pain was reduced by up to 60% within the week postinstrumentation and 80% post root canal filling and the rescue analgesic intake by about 70% on using 1.3% NaOCl compared to 5.25% NaOCl.