Inferior alveolar nerve block (IANB) is the most frequently used injection technique for achieving local anaesthesia for root canal treatment of mandibular teeth. However it is not always successful in endodontics with studies failure rates occurring between 44% and 81% of the time.  The aim of this randomised trial was to determine the effect of administration of preoperative lornoxicam (LNX) or diclofenac potassium (DP) on the success of inferior alveolar nerve blocks (IANB) in patients with irreversible pulpitis.

114 patients with irreversible pulpitis of a mandibular posterior were randomly divided into three groups (n = 38). They received identical capsules of either 8 mg LNX, 50 mg DP or placebo (PLAC), one hour before administration of an IANB with 2% lidocaine containing 1:200,000 epinephrine. Anaesthesia was assessed after 15 minutes and access cavities prepared.  The data were analysed using chi-squared tests.

They found  a significant (P < 0.001) difference in the success rates between the LNX and the PLAC groups only (see table).

[table id=4 /]

They concluded:

Pre-operative administration of LNX significantly improved the efficacy of IANB in patients with irreversible pulpitis, whilst the effect of premedication with DP was not significantly different from the PLAC.

Prasanna N, Subbarao CV, Gutmann JL. The efficacy of pre-operative oral medication of lornoxicam and diclofenac potassium on the success of inferior alveolar nerve block in patients with irreversible pulpitis: a double-blind, randomised controlled clinical trial. Int Endod J. 2011 Apr;44(4):330-6. PubMed PMID: 21692235