Dental implants and risk of bleeding in patients on oral anticoagulants: a systematic review and meta-analysis

Background Dental implant placement is safe and predictable, yet optimal management of anticoagulated patients remains controversial. Whilst cessation of anticoagulation pre-operatively should decrease risks of bleeding, risk of thrombosis increases. We aim to define risk of bleeding in patients on oral anticoagulation who are undergoing dental implant placement, in order to establish best management. Methods This systematic review is registered with the National Institute for Health Research (NIHR) PROSPERO database (Registration No: CRD42021233929). We performed a systematic review as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance. Studies were identified using an agreed search strategy within the OVID Gateway (this included Pubmed, MEDLINE, Cochrane Collaborative). Studies assessing bleeding complications in patients who were undergoing dental implant placement were selected. The primary outcome was bleeding events in anticoagulated patients undergoing dental implant placement. Secondary outcomes included any complication requiring further intervention. Results We identified 182 studies through screening, and after review of titles and abstracts reduced this to 8 studies. In these studies, 1467 participants received at least 2366 implants. Studies were analysed for quality using the ROBINS-I risk of bias tool. Four studies were retrospective case reviews, and four were prospective reviews, three of which also blinded the operator to anticoagulation status. There was significant heterogeneity between the included studies. Meta-analysis showed an increased risk of bleeding (RR, 2.30; 95% CI, 1.25-4.24 p = 0.37 I = 7%) when implants were placed in the presence of anticoagulation however these were not clinically significant haemorrhagic events. Conclusion The continuation of anticoagulants peri-operatively during dental implant surgery does increase the risk of clinically non-significant peri- and post-operative bleeding. Dental implant surgery encompasses a broad spectrum of procedures ranging from minor to more invasive surgery with simple local haemostatic measures mitigating the risk of bleeding. The decision to discontinue anticoagulants prior to dental implant surgery must consider patient and surgical factors with the clinician undertaking a risk-balance assessment.