Efficacy of laser adjuvant therapy in the management of post‐operative endodontic pain: A systematic review and meta‐analysis

Abstract Background Postoperative endodontic pain (PEP) is crucial in clinical practice. Recently, the effects of various laser adjuvant therapies in endodontic treatments have been widely evaluated. However, as a virtually side‐effect‐free treatment, its effect on postoperative pain management during endodontic treatment remains controversial. Objectives This review aimed to compare the efficacy of laser adjuvant therapy for pain management after endodontic treatment. Method The Cochrane Library, PubMed, Embase, Scopus and Web of Science databases were systematically searched for articles published until 12 February 2023. The risk of bias in the included studies was evaluated based on the Cochrane risk‐of‐bias assessment tool. Data on continuous outcomes of visual analogue scale pain scores are expressed as standard mean difference (SMD) and dichotomous outcomes of pain prevalence as relative risk (RR). Results We included 22 studies, of which 15 enrolled 892 patients with visual analogue scale pain scores and 7 enrolled 422 patients with pain prevalence. Of the 22 studies, seven studies had a low risk of bias, 10 had a moderate risk of bias and 5 had a high risk of bias. For pain level, the pooled outcomes indicated reduced pain scores in all laser adjuvant therapy, including low‐level laser therapy (SMD = −0.86 [95% CI: −1.16, −0.55] in 24 h and SMD = −0.64 [95% CI: −0.84, −0.43] in 48 h), diode laser therapy (SMD = −0.27 [95% CI: −0.50, −0.04] in 48 h) and photodynamic therapy (SMD = −1.12 [95% CI: −2.18, −0.05] in 24 h). For postoperative pain incidence, a significant correlation was observed with reduced pain incidence rates in the photodynamic therapy group (pooled RR = 0.47 [95% CI: 0.31, 0.72]) but not in the low‐level laser therapy group (RR = 0.89 [95% CI: 0.30, 2.70] at 12 h and RR = 0.57 [95% CI: 0.09, 3.72] at 24 h). Conclusions High‐quality evidence suggests that laser adjuvant therapies such as low‐level laser therapy, diode laser therapy and photodynamic therapy have a positive impact on reducing postoperative endodontic pain intensity. However, the differences in PEP management effects between laser therapies are unknown, and no significant differences were observed among the subgroups. Registration CRD 42023402872 (PROSPERO).