Objectives To evaluate the evidence for a 50,000/mu l platelet count threshold for platelet transfusion for invasive dental procedures in thrombocytopenic patients. Subjects and Methods We searched in MEDLINE/PubMed, EMBASE, the Cochrane Library (Wiley) and Scopus from 1960 through April 2018 for studies on patients with quantitative platelet disorders not related to medical co-morbidities or medications and undergoing invasive dental procedures. Two reviewers conducted assessments independently. Results We found a total of 176 non-duplicate articles, of which 9 cohort studies met our inclusion criteria. The incidence of postoperative bleeding in thrombocytopenic patients was low (4.9%), and we found no difference in bleeding incidence between patients who had platelet transfusion and those who did not. There was no difference in the mean platelet count for patients with and without bleeding. Different modalities are now available to prevent and control bleeding, which may reduce the need for platelet transfusion. Conclusions There is no evidence to support the long-standing dogma of a need for a platelet count >= 50,000/mu l for safe invasive dental procedures. Platelet transfusion effectiveness for haemostasis support could not be determined based on available data. Local measures and antifibrinolytics are the mainstay for the prevention and management of bleeding.