1. ALARA and optimisation in the surgery

Year 3 of 5

This module is 1 hour of the dentist IR(ME)R update (5 hours over 5 years). It maps to GDC outcomes A, C and D.

Optimisation

Once an exposure is justified, IR(ME)R requires it to be optimised: diagnostic information at a dose that is as low as reasonably achievable (ALARA), consistent with the intended purpose. A beautiful image at an unnecessarily high dose is not optimised. An undiagnostic pale image that then needs a repeat is not optimised either.

Practical steps that cut dose without losing diagnosis

• Rectangular collimation for intra-oral work (standard in UK dental guidance)
• Beam-aiming devices / holders so the beam matches the receptor
• The fastest image receptor the practice has standardised on (digital or F-speed film)
• Exposure factors from the employer’s charts for that machine and examination — not “a bit extra to be sure”
• Thyroid and body protection only as current national guidance and your procedures specify (with rectangular collimation, routine patient shielding is often not indicated — follow current UKHSA advice, not habit)

Staff should not hold the receptor in the patient’s mouth.