Sombre-Alfonce

This is really interesting actually. I'm assuming it's a customised mouth bung under the mask. I'm training to work in radiotherapy in Australia, and we tend to cut out a hole in the mask for the bung to prevent discomfort. I've never seen a bung beneath the mask. Even in stereo treatments the mask doesn't cover the mouth.

Similarly, we only cut eye holes if the patient has an issue with claustrophobia, as the brow ridge is one of the best and most stable places to mould the mask to the face. Edit: Although if your treatment is 45 minutes long, I can understand why they would cut the eye holes, most of the treatments we deal with aren't longer than 20.

Wishing you the best man. As we all tend to say to patients on treatment, we all hope to see you around, but not back in the treatment bunker.

Oh so it's attached! That's got to be interesting to put on!

Yep sounds like it's more of a jaw stabilisation tool from your description. 'Mouth bung' might just be an Australian term, but they're also used to depress the tongue into the lower mouth (and hence away from the brain). This makes it easier to avoid dosing it with radiation during treatment.