PubMed ID (PMID): 17990441Pages 449-455, Language: EnglishFroum, Stuart J. / Cho, Sang-Choon / Cho, Young Sung / Elian, Nicolas / Tarnow, DennisThe present study reports on the results of the use of a screw-retained narrowdiameter implant (NDI) system as an option for implant placement in areas of limited bone volume. This retrospective report followed 48 NDIs in 27 patients for 1 to 5 years postloading. No implant failures were reported, yielding a 100% survival rate. The screw-retained attribute of this system allows retrievability of the restorations, which may require replacement because of porcelain fracture, chipping, or a desire to change color. The three diameters available-1.8 mm, 2.2 mm, and 2.4 mm-allow flexibility for a variety of narrow edentulous spaces. These NDIs present a cost-effective alternative for restoring limited spaces with implant restorations, without the bone augmentation or orthodontic procedures required for conventional fixed restorations. The NDI system is approved by the U.S. Food and Drug Administration for long-term use.