This investigation was designed to evaluate clinical feasibility of the use of narrow-diameter implants to support mandibular overdenture. Twelve patients presenting with an edentulous mandible were recruited from 9 dental offices (n=1~2 per office). Each patient received two to four implants in the mandible. The implants were placed without additional bone augmentation. 36 implants were placed in total. All achieved satisfactory crestal bone stability and soft tissue maintenance at 1 year post final prosthetic restoration.