nasal hood
A small, scented or unscented mask placed over the nose to deliver a nitrous oxide–oxygen mixture via inhalation sedation in dental patients.
Full Definition
The nasal hood is the primary delivery device for nitrous oxide–oxygen (N₂O/O₂) inhalation sedation in dentistry. It fits snugly over the patient's nose and features inhalation and exhalation ports connected to the nitrous oxide delivery unit; exhaled gases are scavenged through an attached evacuation system to prevent ambient contamination. Unlike a nasal cannula, the nasal hood seals around the nose to maintain a consistent gas concentration. Editors should hyphenate 'nitrous oxide–oxygen' with an en dash, not a hyphen, when referring to the gas mixture, and should spell 'nasal hood' as two words (unhyphenated). The term should not be confused with 'nasal cannula,' which is an open, non-sealing device.
Usage
Usage note: Do not hyphenate 'nasal hood.' Distinguish from 'nasal cannula'—the hood seals over the nose; the cannula merely rests inside the nostrils. Editors should ensure nitrous oxide scavenging is mentioned alongside nasal hood use in safety-focused documents.
In Context
- "The dental assistant adjusted the nasal hood to achieve a proper seal before initiating the nitrous oxide flow." — Clinical procedure note
- "Scented nasal hoods are available in various flavours to improve patient acceptance, particularly in paediatric dentistry." — Product description in clinical supply catalogue