Yes, but even "soft rays" get absorbed in tissue, and the harmful effects are accumulated. And it's the "whole life dose" (
ie, of the staff) that we're considering here (rather than the occasional blast received by the patient).
But to be honest, I think that a lot of this stuff is just continued because "that's the way we always did it".
There's no harm in Dental Surgeons and their Assistants wearing a dosimeter or "film badge" ... but has anyone ever heard of anyone getting a "heavy dose" in dental practice? Recently, that is.
"Just stand well back" is my advice.