Comparison of the Silhouette and Porter Brown Systems Used in Inhalation Sedation

This is a randomised non-blinded controlled clinical trial, which involves the measurement of efficiency and acceptability of the Silhouette Mask system and compares it with the Porter Brown Mask system used for Inhalation Sedation in children having dental treatment at the Leeds Dental Institute. All eligible participants will be introduced to both masks (Porter Brown and Silhouette) in the assessment session prior to their first treatment session. Then participants will be randomly allocated to undergo treatment under nitrous oxide-oxygen inhalation sedation using either the Porter Brown or the Silhouette System. The efficiency and acceptability will be measured by a feedback questionnaire at the end of the treatment session and the scavenging efficiency will be measured by a diffusion pen which will measure the levels of nitrous oxide in the dentist's environment