Sir, syncope is the commonest medical emergency encountered in the dental clinic.1 When an episode of vasovagal syncope occurs in the dental clinic early placement of the patient into a supine-with-legs-slightly-raised position is essential to correct the reduced cerebral blood flow. Delays in repositioning the patient can result in presyncope progressing to syncope, prolonging recovery.

In the rare event of a cardiac arrest, resuscitation with basic life support requires the patient repositioned into a supine position. In cases of hypoglycaemia and epilepsy also, recovery is aided by a supine position. In an emergency, precious seconds may be wasted in attempting to identify a preset button to place the patient supine. Studies have already questioned the efficacy of chest compression on the dental chair.2 Chances of survival in cardiac arrest are further reduced if the clinician is slow to place the patient into a resuscitation position. A very low (0.3%) rate of cardiac arrest encountered in dental practice means that for most clinicians, a cardiac event encountered on the chair will likely be their first.1 Hence there is a need for a dedicated, non-electric, quick-release mechanism in the form of a button or handle. This separate system would ensure quick visual identification and access in an emergency situation. Surveys of dental offices consistently reveal less than desirable preparedness of personnel to recognise and manage medical emergencies on the dental chair.3

In view of these observations, it appears that the provision of an 'emergency button' would be a prudent addition to dental chair design, which must go beyond aesthetics and ergonomics. Aside from rapid repositioning, the proposed dedicated emergency mechanical override also speeds up the process of making the patient supine; those precious seconds saved would be used to remove instruments from the oral cavity of a dental patient losing consciousness. A manual override safety mechanism should be incorporated into dental chair design.