Reaction times of children having nitrous oxide inhalation sedation for dental procedures

  • A. LyneEmail author
  • J. Johnson
  • D. Baldwin
Original Scientific Article



Inhalation sedation (IHS), using nitrous oxide and oxygen, is a commonly used form of pharmacological behaviour management in paediatric dentistry. Previous studies suggest that IHS causes a delay in reaction time, which recovers to baseline within 10 min.


To observe the reaction times (RT) of children before and after undergoing IHS for dental treatment.


Sixty children from clinics at St Thomas’ Hospital (London, UK) participated in this observational study. RT was measured using an eight-point choice reaction time system (MOART computer panel, Lafayette Instruments). RT was measured twice: before (prior to patient entering clinic for treatment) and after (immediately after discharge from the clinic). A paired-samples t test was used to analyse data.


Fifty-two patients completed the study. There was a statistically significant delay in RT after treatment (p = 0.022). There was no significant correlation between RT and concentration of nitrous oxide, or length of the recovery period.


Children may have a small impairment in reaction times following recovery from IHS in the clinical setting, regardless of the strength of nitrous oxide given, or the length of the recovery period. The child’s escort should be aware of the need to supervise the child following discharge.


Sedation Nitrous oxide Paediatric dentistry Inhalation sedation Conscious sedation 



All authors would like to express thanks to the families that participated in this research, as well as the staff in the Paediatric Dentistry department at St Thomas’ Hospital.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© European Academy of Paediatric Dentistry 2019

Authors and Affiliations

  1. 1.Department of Paediatric Dentistry, Guy’s and St Thomas’ NHS Foundation TrustLondonUK
  2. 2.Faculty of Dentistry, Oral & Craniofacial SciencesPaediatric Dentistry, Centre of Oral Clinical and Translational Science, King’s College London, The StrandLondonUK

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