1. Justification: no exposure without benefit

Year 2 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.

What justification means

An exposure is justified only if the clinical benefit outweighs the radiation detriment, taking account of other techniques that involve less or no ionising radiation. “We always take bitewings at recall” is not justification. “The patient has new interproximal caries risk / I cannot see the contacts clinically” can be.

Who decides

The practitioner justifies. The referrer supplies enough information. If you are both, you still need a recorded clinical reason. Authorisation (the practical go-ahead) must follow the employer’s procedure — often the same dentist signs or the software logs it.

What cannot justify an exposure

• Patient demand with no clinical indication
• Medico-legal curiosity (“in case we get complained about”) without a diagnostic question
• Copying the last dentist’s six-monthly habit when risk has changed
• A blank “routine radiograph” tick on a template

Previous images must be considered. If adequate recent radiographs exist and answer the question, a new exposure is not justified.