The effect of preoperative submucosal administration of tramadol on the success rate of inferior alveolar nerve block on mandibular molars with symptomatic irreversible pulpitis: a randomized, double-blind placebo-controlled clinical trial

Abstract

Aim: This randomized, double-blind, placebo-controlled, clinical trial was designed to improve the success of inferior alveolar nerve blocks (IANB) in mandibular molars with symptomatic irreversible pulpitis (SIP) by means of preoperative submucosal administration of 50 mg tramadol.

Methodology: Forty-two patients with a mandibular molar diagnosed with SIP took part in the trial. Patients were assigned randomly to one of two groups: tramadol group (n = 21), who received 50 mg tramadol in 1 mL by mandibular infiltration, and a placebo group (n = 21), who received 1 mL of normal saline administered to the affected tooth by the same means. Ten minutes later, all patients received an IANB with 4% articaine with epinephrine 1 : 100 000. A 10-min waiting time was established after local anaesthetic (LA) administration before carrying out three consecutive tests to assess anaesthesia of the pulp, that is two consecutive negative responses to an electric pulp test, positive or negative response to a cold test and no pain during access cavity preparation. IANB was considered successful only if the patient did not experience pain arising from these tests. Data were analysed by the Chi-squared frequency test and the Fisher's exact test, for qualitative variables, Mann-Whitney U-test for independent samples and two-way anova for more than two independent samples.

Results: In the tramadol group IANB was achieved successfully in 57% of the sample, whilst the placebo group obtained 29%. The difference between groups was not significant (P = 0.06). When performing endodontic access, the anaesthetic success rate was significantly in favour of tramadol (P = 0.03).

Conclusions: Preoperative submucosal administration of 50 mg tramadol in mandibular molars with SIP significantly improved the success of IANB using 4% articaine with 1 : 100 000 epinephrine during access cavity preparation in comparison with a placebo.

Keywords: anaesthesia failure; articaine; inferior alveolar nerve block; mandibular infiltration; symptomatic irreversible pulpitis; tramadol.