Meta-analysis of the association between common interleukin-1 polymorphisms and dental implant failure

Interleukin-1 (IL) plays a pivotal role in immune-inflammatory response that maintains periodontal homeostasis. A number of epidemiological studies have been conducted to investigate the associations between common polymorphisms of IL-1 (IL-1A, IL-1B) genes and risk of peri-implant disease, but the findings remain inconclusive. Thirteen studies evaluating the association between IL-1 polymorphisms and risk for peri-implant diseases (implant failure/loss, peri-implantitis) were included. Fixed model or random-effects models were applied to calculate overall and ethnicity-specific summary odds ratios (ORs) and corresponding 95% confidence intervals (CIs) as risk estimates for IL-1 polymorphisms individually or in combination. Heterogeneity and publication bias were evaluated by Q-test, I2 statistic, Begg's funnel plot and Egger's test accordingly. The composite genotype of IL-1A (-889) and IL-1B (+3954) was associated with increased risk of implant failure/loss (OR 1.76, 95% CI 1.21-2.57) and peri-implantitis (OR 2.34, 95% CI 1.03-5.33). The significance was borderline in European descents (implant failure/loss: OR 1.48, 95% CI 0.99-2.22; peri-implantitis: OR 1.65, 95% CI 1.00-2.73). T allele of IL-1B (-511) was associated with increased risk of implant failure/loss (OR 1.28, 95% CI 1.01-1.62), while the association was not significant in European descents (OR 1.12, 95% CI 0.85-1.48). These findings support a potential role of IL-1 polymorphisms, particularly the composite genotype of IL-1A (-889) and IL-1B (+3954), in peri-implant disease susceptibility. More studies with large sample size are needed to validate the associations.