Nitrous oxide analgesia in selected dental patients.

Nitrous oxide analgesia is presented as the analgesic method of choice in medically compromised patients. The resemblance between the action of nitrous oxide and that of morphine is emphasized. The combination of the opiate-like action of nitrous oxide with the advantages of an inhalation technique makes it preferable and superior to parenteral opiate administration. It may thus be termed as an inhalation "opiate".Since its introduction into clinical use by Wells in 1844 (1), nitrous oxide (N(2)0) has been applied as an anesthetic and analgesic agent in various medical situations, including dentistry (2). The development of equipment affording safe administration of accurate concentrations of either pre-mixed or adjustable N(2)0 and oxygen enabled the application of "relative analgesia" as an important technique in the relief of pain. The pharmacological action and analgesic properties of N(2)0 received renewed interest after Berkowitz et al (3) showed the resemblance between its mode of action and that of opiates. Recent human and animal studies indicated that N(2)0 activates the endogenous opiate system(s) in a manner similar to that of morphine (4). The availability of an analgesic gas which, on the one hand, mimics opiate action whilst on the other hand its administration is continuously adjustable, as opposed to other modes of sedation, makes it into an ideal adjunct in dental procedures. Owing to its minimal side effects, the use of N(2)0 is especially recommended in the management of anxious children and medically compromised patients.This report presents three illustrative patients in whom nitrous oxide proved to be the drug of choice during dental procedures.