A systematic review of the prognosis of short (<10 mm) dental implants placed in the partially edentulous patient.

AIM This study evaluated, through a systematic review of the literature, the estimated implant survival rate of short (<10 mm) dental implants installed in partially edentulous patients. MATERIALS AND METHODS A systematic search was conducted in the electronic databases of MEDLINE (1980-October 2009) and EMBASE (1980-October 2009) to identify eligible studies. Two reviewers independently assessed the methodological quality of the articles using specific study design-related quality assessment forms. RESULTS Twenty-nine methodologically acceptable studies were selected. A total of 2611 short implants (lengths 5-9.5 mm) were analysed. An increase in implant length was associated with an increase in implant survival (from 93.1% to 98.6%). Heterogeneity between studies was explored by subgroup analyses. The cumulative estimated failure rate of studies performed in the maxilla was 0.010 implants/year, compared with 0.003 found in the studies in the mandible. For studies that also included smokers, the failure rate was 0.008 compared with 0.004 found in studies that excluded smokers. Surface topography and augmentation procedure were not sources of heterogeneity. CONCLUSION There is fair evidence that short (<10 mm) implants can be placed successfully in the partially edentulous patient, although with a tendency towards an increasing survival rate per implant length, and the prognosis may be better in the mandible of non smoking patients.