Tilted implants in the immediate loading rehabilitation of the maxilla: a systematic review.

Tilted implants have been proposed as an alternative to traditional protocols in the rehabilitation of edentulous maxillae. The aim of this meta-analysis was to evaluate the outcomes of upright and tilted implants supporting full-arch fixed dentures for the immediate rehabilitation of edentulous maxillae, after at least 1 year of function. An electronic search of databases and a hand search of relevant journals in oral implantology were performed according to PRISMA guidelines through August, 2011. The literature search yielded 1,069 articles. Eleven articles were available for analysis. A total of 1,623 implants (778 tilted, 845 upright) were inserted into the maxillae of 324 patients. Seventeen tilted (2.19%) and 16 upright implants (1.89%) failed during the first year. No significant difference in failure rate was found between tilted and upright implants (p value = 0.52). Marginal bone level results were obtained from 6 studies. A non-significant mean difference between tilted and upright implants was found with regard to bone loss. Tilted implants demonstrated a favorable short-term prognosis in full-arch immediate loading rehabilitations of the maxillae. Randomized long-term trials are needed to better elucidate long-term success of tilted vs. upright-positioned implants.