A blinded randomized controlled trial comparing lignocaine and placebo administration to the palate for removal of maxillary third molars

Routine use of a palatal injection for the removal of maxillary third molars has never been validated. The purpose of this blinded, randomized, controlled trial was to assess the requirement of a separate palatal injection for the extraction of maxillary third molars. Fifty-one patients requiring the removal of bilateral maxillary third molars were enrolled. Each patient acting as their own control received buccal infiltrations of lignocaine bilaterally, then 0.2 mL of lignocaine without vasoconstrictor was administered to one side of the palate and the same amount of normal saline administered to the other side. Sides were randomized as to the active ingredient and both the patient and operator were blinded. All extractions were performed by a single operator using a consistent technique and no additional sedative or anaesthetic agents were utilized. Data relating to the pain of the extractions and of the palatal injection were obtained on a Visual Analogue Scale (VAS). Verbal Response Scale (VRS) data were obtained additionally for a subset of 21 patients. Statistical analysis confirmed clinical equivalence between saline and lignocaine to the palate (95% CI - 1.7 to 6.2 mm, equivalence range -6.75 to 6.75 mm). No patients requested additional lignocame to the palate in order to ensure comfortable extraction. This study provides evidence that the poorly tolerated palatal injection of local anaesthetic for the removal of maxillary third molars may not be required.