CLINICAL MEDICINE

Detailed explanation-1: -The purpose of the lead foil in the film packet is to absorb back-scattered x-rays to reduce film fog. A sheet of lead foil is located in the back of the film packet, behind the film. The purpose of the lead foil backing is to absorb scattered radiation.

Detailed explanation-2: -The lead foil in a dental film packet is considered to have two roles. One is to reduce the absorbed dose in the tissues behind the film packet, and the other is to prevent the back scatter radiation from such tissues to maintain image quality.

Detailed explanation-3: -Lead foil screens diminish the effect of scattered radiation, particularly that which undercuts the object (See “Scattered Radiation"), when the primary rays strike the portions of the film holder or cassette outside the area covered by the object.

Detailed explanation-4: -Elemental lead from lead foil in radiographic packets is a leachable toxin that can contaminate the soil and groundwater in landfill sites. Lead foil must be treated as hazardous waste.

Detailed explanation-5: -Lead has long been recognized as a highly effective material in pro-viding protection from various sources of radiation, and as such, has become a standard in the design of radiation protection systems.