Why were lead vests used in past years?

Lead vests and thyroid collars have been worn by countless Americans during dental x-rays over the years. They've been in use for far longer than my lifetime — about 100 years. The heavy apron-like shields are placed over sensitive areas, including the chest and neck, before the x-rays are taken.

"I haven't worn a lead apron in the last 10 or 15 years — unless a dentist insists I put it on — because I know it isn't needed," says Dr. Bernard Friedland, an associate professor of oral medicine, infection, and immunity at Harvard School of Dental Medicine.