Survival and patient satisfaction of short implants during the first 2 years of function: a retrospective cohort study with 694 implants in 416 patients

The present study aimed to evaluate the influence of implant length on implant survival and patient satisfaction during the first 24 months in function.

A retrospective cohort of 312 "short" Straumann(®) SLActive(®) implants (length ≤ 8 mm) in 224 patients, which were inserted between 2008 and 2010 in private practice, were evaluated. The mean observation period was 26.7 ± 9.7 months. Three hundred and eighty-two Straumann SLActive(®) implants in 192 patients with a length ≥ 12 mm served as control group. The mean observation period in the control group was 28.3 ± 10.1 months. Implant survival rate, crown-to-implant ratio, resonance frequency analysis, and patient satisfaction were evaluated.

Implant survival rate was 99% in the test vs. 98.7% in the control group. The crown-to-implant ratio was significantly higher in the control group (P < 0.0001). Resonance frequency analysis showed slightly higher values for the short implants. There was a tendency to higher satisfaction (Oral Health Impact Profile [OHIP]) in the test group without statistical significant differences but a high overall satisfaction in both groups.

Within the limits of the present investigation, implant length had no significant influence on implant survival during the first 24 months of function of the specific implant system with hydrophilic surface (SLActive(®) ). Further follow-up studies are required to evaluate long-term results of the reduced implant length.