The article demonstrates the factors of importance in the early and late failures of dental implants based on literature review. An implant location is one of many factors that can influence a success or failure of dental implants. The author identifies and describe four alveolar jaw regions--functional implant zones--with unique characteristics of anatomy, blood supply, pattern of bone resorption, bone quality and quantity, need for bone grafting and other supplemental surgical procedures, and a location-related implant success rate. The article discusses predisposing factors that can lead to early implant failures in different jaw zones. An implant location is investigated as one of these factors. A prior history of trauma to premaxillary region is described in the context of implant success in anterior maxilla. This zone is being referred by the author as the "traumatic zone." The challenges of mandibular posterior implant reconstruction are presented in the context of blood supply to the mandible. A deficiency of vascularization in this region, especially in elderly and edentulous patients, lead the author to refer to this zone as the "ischemic zone." The concept of relative ischemia of the posterior mandible that can develop with age and tooth loss is discussed. A thorough understanding of specifics of each functional implant zone should help to improve successes and prevent failures of dental implants.