Safety and feasibility of immediate implant placement in diabetic patients: A systematic review and meta-analysis

The increasing use of dental implants raises questions about their efficacy in diabetic patients, particularly for immediate implant placement (IIP). Well-controlled diabetic patients may achieve success rates comparable with healthy individuals. To the best of our knowledge, however, comprehensive meta-analyses on IIP outcomes in diabetics remain limited. The present study aimed to judge whether IIP could be adopted in diabetic patients. A systematic search was conducted in PubMed, Embase, Web of Science, Cochrane, Google Scholar and China National Knowledge Infrastructure databases (January 2000 to March 2025). Studies comparing implant survival rates (SR), marginal bone loss (MBL), probing depth (PD) and bleeding on probing (BOP) between diabetic (well-/poorly controlled) and healthy patients undergoing IIP were included. The methodological quality and risk of bias of the included studies were assessed using the Newcastle-Ottawa Scale. Meta-analysis was performed using RevMan 5.4 software to calculate mean difference (MD) and risk ratio (RR) with 95% confidence interval (CI). A random-effects model was employed to address heterogeneity. A total of 10 studies (1,350 patients, 1,623 implants) were included in the analysis, demonstrating moderate to high methodological quality overall. Compared with healthy patients, well-controlled diabetic patients showed no significant difference in SR (RR=1.00, 95% CI: 0.97-1.02, P=0.79); similarly, poorly controlled diabetic patients also exhibited SR comparable with what of healthy patients (RR=0.96, 95% CI: 0.88-1.06, P=0.47). However, well-controlled diabetic patients had significantly higher MBL than healthy patients (MD=0.08, 95% CI: 0.03-0.14, P=0.004), while poorly-controlled diabetic patients showed greater MBL (MD=0.39, 95% CI: 0.25-0.53, P<0.00001). Additionally, well-controlled diabetic patients showed no significant difference in PD compared with healthy patients (MD=0.17, 95% CI: -0.02-0.37, P=0.09), but had significantly higher BOP (MD=0.12, 95% CI: 0.07-0.17, P<0.00001). Poorly-controlled diabetic patients demonstrated significantly higher PD (MD=0.62, 95% CI: 0.38-0.86) and BOP (MD=0.24, 95% CI: 0.23-0.24; both P<0.00001). There was notable heterogeneity among studies included in the meta-analysis and individual studies may influence the overall findings. Despite these limitations, the present results suggested that for diabetic patients, particularly those with optimal glycemic control, IIP demonstrates comparable implant SR with healthy individuals, confirming its clinical feasibility. However, diabetic patients, especially those with poor glycemic control, face increased risks of peri-implant bone loss and inflammation. Strict preoperative glycemic management and diligent postoperative care are key to minimize complications and ensure long-term implant SR.