Radiation therapy is defined as the therapeutic use of ionizing radiation. The 2 principal types of ionizing radiation are electromagnetic irradiation and particle irradiation. In irradiation of implants in bone, it is recommended the removal of all abutments and superstructures and closure of skin and mucosa over the implants prior to radiation.  Radiation therapy can begin when healing is complete.
Irradiation of dental implants in bone results in backscatter. The tissues on the radiation source side of the implants receive a higher dose than the other tissues in the field. The dose in increased by about 15% at 1 mm from the dental implant. 
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