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The purpose of the review was to investigate the efficacy of platelet concentrates (containing pure platelet-rich plasma, leukocyte- and platelet-rich plasma, pure platelet-rich fibrin, and leukocyte- and platelet-rich fibrin) used in alveolar ridge preservation (ARP), especially the changes in alveolar width and height.Randomized clinical trials that compared the efficiency of platelet concentrates used in ARP were searched till June 2017 in 6 databases: PubMed, Cochrane Central Register of Controlled Trials, EMBOSE, EMBASE, Web of Sciences, and AMED. A meta-analysis would be performed if the heterogeneity was acceptable.Five articles were included in the qualitative analysis. A meaningful meta-analysis could not be performed because of the obvious heterogeneities among studies. Three studies showed that leukocyte- and platelet-rich fibrin had a benefit in preserving ridge width or height or both, whereas 2 studies showed that platelet-rich plasma had no significant benefit.The effects of different kinds of platelet concentrates used in ARP might be different. Leukocyte- and platelet-rich fibrin might have a more positive effect on alveolar width and height preservation than platelet-rich plasma. However, randomized clinical trials included in the review were few and the strong evidence on this topic was not yet enough.