Autologous Platelet Concentrates for Pulp and Dentin Regeneration: A Literature Review of Animal Studies

• After revascularization using autologous platelet concentrates, neoformed intracanal tissues are mainly cementumlike, bonelike, and fibrous connective tissue, meaning that true regeneration of necrotic pulp may not be achieved.
• Using either autologous platelet concentrates or blood clot, root wall thickening, root lengthening, and root apex closure are radiographically achieved.
• Despite not restoring true pulp tissue, the management of necrotic teeth with autologous platelet concentrates may lead to clinical success.

IntroductionThe purpose of this study was to evaluate the effectiveness of autologous platelet concentrates (APCs) in promoting pulp and dentin regeneration in animal models.MethodsAn electronic search was performed on MEDLINE, Embase, Scopus, SciELO, LILACS, and CENTRAL. Animal studies using APC as a root filling material after pulpectomy in mature or immature teeth were included. Articles underwent risk of bias assessment. Histologic evaluation of intracanal neoformed tissue was the primary outcome; root development, root wall thickening, apical closure, and periapical healing in apical periodontitis were the secondary outcomes.ResultsSeven articles were included. Platelet-rich plasma (PRP) was used as root filling material during regenerative procedures in the experimental group in either mature or immature teeth. After revascularization with PRP alone or in conjunction with stem cells of a different source, the histologic analyses revealed that, in addition to an odontoblastic cell layer or dentinlike structure, the neoformed intracanal tissues were mainly cementumlike, bonelike, and connective tissues.ConclusionsTrue regeneration of necrotic pulp may not be achieved with current techniques using PRP, all of which stimulated tissue repair. Benefits of PRP adjunct for pulp tissue regeneration in preclinical studies remain unclear. Further studies with standardized protocols are necessary to assess the actual contribution of PRP in endodontic regenerative therapies.