Local anaesthesia for surgical extraction of mandibular third molars: a systematic review and network meta-analysis

Objectives: Pain management for the extraction of the mandibular third molar is a challenge as compelling evidence in comparative anaesthetics is currently lacking.

Materials and methods: Thorough literature searches took place in PubMed, ScienceDirect, CENTRAL, Embase, Web of Science, CBM, and CNKI. Thirty-three trials were meta-analysed using a Bayesian statistical approach within the random-effects model. Grading of Recommendations Assessment, Development, and Evaluation was performed to determine the overall quality of evidence across all comparisons.

Results: In terms of success rate, an inferior alveolar nerve block (IANB) injection of 2% lidocaine with epinephrine was less effective than a combined injection of buccal infiltration (BI) and lingual infiltration (LI) with a 4% articaine (RR = 0.85 [0.75, 0.96], P = 0.611). According to visual analogue scale (VAS), 2% lidocaine-IANB with epinephrine caused higher VAS scores than 4% articaine-IANB with epinephrine (MD = 0.84 [0.28, 1.40], P = 0.057), whereas 0.5% levobupivacaine-IANB showed lower scores than 2% lidocaine-IANB (MD = - 1.62 [- 2.97, - 0.28], P = 0.045). Also, 2% lidocaine-IANB with epinephrine presented longer latency than both 4% articaine-IANB with epinephrine (MD = 39.44 [16.97, 61.90], P < 0.001) and 4% articaine-BI + LI with epinephrine (MD = 164.41 [16.23, 312.58], P < 0.001); 4% articaine-IANB with epinephrine produced shorter latency than 0.5% bupivacaine-IANB with epinephrine (MD = - 42.92 [- 70.28, - 15.56], P = 0.106); 0.75% ropivacaine-IANB caused shorter onset of action compared with 2% lidocaine-IANB (MD = - 40.88 [- 65.50, - 16.26], P < 0.001). In addition, 2% lidocaine-IANB with epinephrine produced significantly shorter duration than both 4% articaine-IANB with epinephrine (MD = - 47.33 [- 57.88, - 36.77], P = 0.265) and 2% mepivacaine-IANB with epinephrine (MD = - 10.01 [- 19.59, - 0.44], P = 0.769). The duration of action triggered by 4% articaine-IANB with epinephrine was shorter compared with 0.5% bupivacaine-IANB with epinephrine (MD = - 64.17 [- 74.65, - 53.69], P = 0.926). Both 0.5% levobupivacaine-IANB and 0.75% ropivacaine-IANB produced longer duration of action than 2% lidocaine-IANB (MD = 333.70 [267.33, 400.07], P < 0.001) and (MD = 288.01 [287.67, 288.34], P = 0.634, respectively).

Conclusions: The network meta-analysis demonstrated that the intraosseous injection of 4% articaine with epinephrine had the most noteworthy success rate. However, the combination of BI and LI of 4% articaine with epinephrine, and IANB of 0.5% bupivacaine were, according to a VAS, the most effective. It should be noted that a rapid onset of action was produced by BI combined with LI of 4% articaine with epinephrine and IANB of 2% mepivacaine with epinephrine, while the most prolonged duration of action was generated by IANB of 0.5% levobupivacaine or 0.5% bupivacaine.

Clinical relevance: For a better understanding of local anaesthesia for the extraction of the third molar, our study was aimed to provide evidence to guide better dental practices in pain management for clinicians.