Survival of short dental implants for treatment of posterior partial edentulism: a systematic review.

PURPOSE: Dental implant therapy for posterior partial edentulism may utilize short implants. The advantages of short implants include the ability to avoid the additional surgical procedures that would be required to place longer implants. The aim of this study was to systematically review studies concerning dental implants of ≤ 8.5 mm placed in the posterior maxilla and/or mandible to support fixed restorations.
MATERIALS AND METHODS: English-language articles published between 1992 and May 2011 were identified electronically and by hand search of the PubMed, Embase, and Cochrane libraries. Data were extracted and compared statistically. Forest plots were generated to compare outcomes of short versus long implants.
RESULTS: An initial screening of 1,354 studies led to direct evaluation of 401 articles. Of these, 33 met the research criteria: 5 randomized clinical studies; 16 prospective, nonrandomized, noncontrolled studies; 12 retrospective, nonrandomized studies; and 1 study with both prospective and retrospective data. These studies indicated that there is no significant difference in the reported survival of short versus long implants. Failure of 59 of 2,573 short implants at 1 year was recorded, with 71% of them failing before loading. Only 101 short implants were followed for 5 years.
CONCLUSIONS: The initial survival rate for short implants for posterior partial edentulism is high and not related to implant surface, design, or width. Short implants may constitute a viable alternative to longer implants, which may often require additional augmentation procedures.