Short implants versus bone grafting and standard-length implants placement: a systematic review

Objectives The aim of this study was to conduct a systematic review to compare the survival rates between short implants (length < 10 mm) versus standard-length implants (≥ 10 mm) inserted in grafted bone. As secondary outcomes, marginal bone loss and survival rates of the implant supported prosthe- ses were also analysed. Materials and methods Randomised controlled trials (RCT) that compared both techniques were searched on three elec- tronic databases till June 2016, a manual search was per- formed on the bibliography of the collected articles, and the authors were contacted for additional references. The esti- mates of the interventions were expressed in relative risk (RR), mean implant survival rates and mean differences in marginal bone. Results Eight RCTs were included in this study. From a total of 458 short implants, 15 failed (mean survival rates = 96.7%), While from 488 regular implants, 13 failed (mean survival rates = 97.3%). The technique did not significantly affect: the implant failure rate (P > 0.05), with RR of 1.34 (95% CI 0.67–2.87), the mean differences of marginal bone loss (P = 0.18; MD − 0.04 mm [− 0.10; 0.02] 95% CI), at loading or prosthesis failures rates (RR:0.98; 95% CI 0.40–2.41). The mean differences of marginal bone at 1 year follow-up (post loading) presented significant marginal changes in the short implant group (P = 0.002; MD − 0.10 mm [− 0.16; − 0.03] 95% CI) although a significant high heterogeneity was found between groups. Conclusions This systematic review suggests no difference between both techniques in the treatment of atrophic arches. However, more long-term RCTs are needed to evaluate the predictability at the long run. Clinical relevance The use of short implants might be consid- ered an alternative treatment, since it usually requires fewer surgical phases and tends to be a more affordable option.