Periodontally compromised vs. periodontally healthy patients and dental implants : a systematic review and meta-analysis

OBJECTIVES: To test the null hypothesis of no difference in the implant failure rates, postoperative infection, and marginal bone loss for the insertion of dental implants in periodontally compromised patients (PCPs) compared to the insertion in periodontally healthy patients (PHPs), against the alternative hypothesis of a difference. METHODS: An electronic search without time or language restrictions was undertaken in March 2014. Eligibility criteria included clinical human studies, either randomized or not. RESULTS: 2768 studies were identified in the search strategy and 22 studies were included. The estimates of relative effect were expressed in risk ratio (RR) and mean difference (MD) in millimetres. All studies were judged to be at high risk of bias, none were randomized. A total of 10,927 dental implants were inserted in PCPs (587 failures; 5.37%), and 5881 implants in PHPs (226 failures; 3.84%). The difference between the patients significantly affected the implant failure rates (RR 1.78, 95% CI 1.50-2.11; P<0.00001), also observed when only the controlled clinical trials were pooled (RR 1.97, 95% CI 1.38-2.80; P=0.0002). There were significant effects of dental implants inserted in PCPs on the occurrence of postoperative infections (RR 3.24, 95% CI 1.69-6.21; P=0.0004) and in marginal bone loss (MD 0.60, 95% CI 0.33-0.87; P