Single tooth anesthesia versus conventional anesthesia: a cross-over study

The aim of the present study was to compare an electronic device, the Wand Injection System (Milestone Scientific Livingstone), with conventional anesthesia in terms of the following: pain sensation during anesthetic injection; effectiveness in achieving adequate anesthesia for a complete painless dental treatment; post-operative discomfort; and patient's anxiety toward dental treatment.

Eighty adults from 18 to 70 years were enrolled in this cross-over study. Each patient served as his/her own control being subject to two anesthesia techniques: conventional and Single Tooth Anesthesia (STA) performed with the Wand. A split-mouth design was adopted in which each tooth undergoing conservative restorative or endodontic treatment received anesthesia with both techniques at 1-week interval. Before anesthetic administration, the patients' anxiety levels were determined. Physiological parameteres were measured before, during, and after the two injection procedures, and the Visual Analogue Scale (VAS) was used to assess pain of injection, discomfort, and anesthetic efficacy. Differences in assessment of pain's injection, discomfort, anesthetic efficacy, vital parameters (heart rate, blood pressure, and oxygen saturation), and state anxiety levels were analyzed using Student's t test (p value < 0.001).

The mean injection pain and post-operative discomfort ratings with Wand were lower than those with conventional syringe (p = 0.022 and p < 0.001, respectively). No differences were found in the assessment of anesthetic efficacy. Blood pressure and heart rate mean values were lower during the anesthesia performed with the Wand than with the conventional syringe (p < 0.001). The anxiety level was higher during the first appointment, independently from the device used for the injections.

The STA technique resulted in lower pain, discomfort, and lower intensity of physiological parameters.

Single Tooth Anesthesia could be an efficacious alternative to conventional procedures.