Retromolar canal infiltration as a supplement to the inferior alveolar nerve block injection: an uncontrolled clinical trial.

OBJECTIVES

This study aimed to determine the success rate of retromolar canal (RMC) infiltration following the failure of inferior alveolar nerve block (IANB) injections for the anesthesia of mandibular first molars with acute irreversible pulpitis.

MATERIALS AND METHODS

An IANB injection was administered for 50 patients with acute irreversible pulpitis. Lip numbness was set as the sign of anesthesia and further evaluated and confirmed with pulp sensibility tests after 10-15 min. Access cavity preparation was commenced unless the patient felt any pain; in this case, an RMC infiltration injection was given. The success rate was determined through the patients' recording of the presence, absence, or reduction of pain severity during access cavity preparation using the Heft-Parker visual analog scale.

RESULTS

Seven patients (14%) did not experience any pain by pulp sensibility tests and during access cavity preparation after IANB injection. Twenty-five (58.1%) of the remaining 43 patients who had the RMC infiltration injection had reduced pain, and four patients (9.3%) experienced no pain after the RMC infiltration. Fourteen patients (32.5%) experienced no change in pain. Chi-squared test results revealed that the percentage of patients with reduced pain was higher than that of other patients (P < 0.001).

CONCLUSIONS

RMC infiltration, along with IANB, significantly reduced the pain felt by patients and increased the success of the anesthetic technique for root canal treatment of mandibular first molars with acute irreversible pulpitis.

CLINICAL RELEVANCE

The administration of RMC infiltration can enhance the success of the IANB technique for anesthetizing mandibular first molars exhibiting acute irreversible pulpitis.