Pain behaviour and distress in children during two sequential dental visits: comparing a computerised anaesthesia delivery system and a traditional syringe

Objective To compare the pain and distress response of children receiving a local anesthesia injection using a computerised device (Wand®) or a traditional syringe over two consecutive treatment sessions and to study whether the response to the two injection techniques was different for high or low dentally anxious children. Design Randomised controlled trial. Setting Secondary dental care practice specialised in treating children. Subjects and Methods Children were selected and randomly allocated to the Wand® or traditional injection condition. Parents completed the Dental Subscale of the Children's Fear Survey Schedule (CFSS-ds). Based on video recordings of the injections, for each 15 seconds, the occurrence of five pain related behaviours was registered and a score was given on the Venham distress scale. Children rated their pain after each injection. Intervention Over two consecutive treatment sessions one group received two local anaesthesia injections with the traditional syringe and the other group received two injections with the Wand®. Outcome measures The mean number of pain related behaviours, the mean distress scores and the self-reported pain scores were compared. Based on the CFSS-ds subjects were split into highly and low dentally anxious children. Results One hundred and forty-seven subjects participated in the study: aged 4-11 years, 71 girls. Based on the behaviour displayed during the local anaesthesia injection and the self-reported pain after the injection, no difference could be found between an injection with the traditional syringe or the Wand® over the first or second treatment session. However, on the first treatment session, highly anxious children reported more pain (p = 0.001), displayed more pain related behaviour (p = 0.002) and more distress (p