Survival and complications of zygomatic implants: an updated systematic review ABSTRACTPurpose: To assess the survival rate of zygomatic implants (ZIs) and the prevalence of complications based on previously published studies.Methods: An electronic search was performed in December/2015 in three databases and was supplemented by hand-searching. Clinical series of ZIs were included. Interval survival rate (ISR) and cumulative survival rate (CSR) were calculated. The untransformed proportion of complications (sinusitis, soft tissue infection, paresthesia, oroantral fistulas) was calculated, considering the prevalence reported in the studies.
Results:Sixty-eight studies were included, comprising 4556 ZIs in 2161 patients, with 103 failures.The 12-year CSR was 95.21%. Most failures were detected within the six-month postsurgical period. Studies (n=26) that exclusively evaluated immediate loading showed a statistically lower ZI failure rate than studies (n=34) evaluating delayed loading protocols (P=0.003). Studies (n=5) evaluating ZIs for the rehabilitation of patients after maxillary resections presented lower survival rates. The probability of presenting postoperative complications with ZIs was as follows: sinusitis 2.4% (95%CI 1.8-3.0), soft tissue infection 2.0% (95%CI 1.2-2.8), paresthesia 1.0% (95%CI 0.5-1.4), oroantral fistulas 0.4% (95%CI 0.1-0.6). However, these numbers may be underestimated, as many studies failed to mention the prevalence of these complications.
Conclusion:ZIs present a high 12-year CSR, with most failures occurring at the early stages postoperatively. The main observed complication related to ZIs was sinusitis, which may appear several years after ZI installation surgery.