Background: Inserting dental implants in severely atrophied jawbones is a great challenge for the dental practitioner. There are an increasing number of patients who choose dental implantanchored prosthetic restorations despite compromised bone quality and quantity. There have been numerous attempts in adapting implant design for the atrophic crestal bone. One-piece, needle-type basal implant design is a typical design for these cases. These implants are inserted in the remaining compact bone located in the basal aspect of the jawbones. If high primary stability is achieved, these implants are used for immediate loading protocol. From many points of view, this technique is based on contradictory principles compared to classic implant surgery and loading protocols. The aim of this study was to investigate the long-term success of basal one-piece short-diameter dental implants used for immediate loading protocol. Materials and methods: A total of 56 dental implants were included in this study. Peri-implant bone loss was measured on orthopantomographs. Bone resorption was measured in millimeters in the first 6 and 12 months of functional loading. Results: There were no failing implants in this period; average bone resorption was 1.59 mm after 6 months of functional loading and 2.05 mm after 12 months. Bone resorption was slightly higher in the mandible than in the maxilla. Conclusions: Immediate implant loading protocol might be an attractive solution for fixed fullarch restoration using short-diameter one-stage basal implants, but long-term effects require further investigations.