Methodological and study design issues restricted the possibility to draw robust conclusions. Within the limits of this review, it might be concluded that there is no obvious association between specific genetic polymorphism and dental implant failure in terms of biological complications, although a tendency should be underlined showing the potential link between IL-1 genotype and peri-implantitis. Well designed and adequately powered prospective cohort studies are needed to provide further information.

Background: There is a lack of consensus on measures to assess implant performance in clinical research. Objectives: To investigate the outcomes measures and reference groups employed to evaluate and compare implant success and failure. Data Sources: MEDLINE (OVID) and Web of Science with searching reference lists of included papers.