Cancer associated with maxillofacial part is most common type of disorder, and it accounts for more than 550,000 cases annually worldwide. Multidimensional potential risk factors of dental implants failure must be considered when planning implant placement therapy in patients undergoing radiation therapy especially in maxillofacial region. Meticulous treatment planning along with careful preoperative oral examination and good coordination with oncologic specialists cannot be overemphasized. It is also important for the dental profession to keep abreast of the latest available radiation therapy technologies. Additional evidence-based clinical guidelines for implant use in patients undergoing radiation therapy are expected. Hence this paper reviews on literature behind the effect of radiations on dental implants.