Histological findings of revascularized/revitalized immature permanent molar with apical periodontitis using platelet-rich plasma

Introduction: An immature mandibular right first molar (#30) with apical periodontitis of a 9-year-old boy was treated with a revascularization/ revitalization procedure using either a mixture of platelet-rich plasma (PRP) and a blood clot or a blood clot alone on the same tooth. Methods: Tooth #30 fractured 2 years and 1 month after the revascularization/revitalization procedure and could not be saved. The tooth was extracted and processed for histologic examination to determine the nature of the tissues that formed in the canals. Results: Clinically, the endodontic treatment of the case was successful based on the resolution of apical periodontitis and the absence of clinical signs and symptoms. Histologically, the tissues formed in the distal and mesial canals were mineralized tissue similar to cementoid/osteoid tissue and uninflamed fibrous connective tissue regardless of PRP or no PRP treatment. No pulp-like tissue characterized by the presence of odontoblast-like cells polarized along the dentin-like mineralized tissue was observed. Conclusions: The tissues formed in the canals were mineralized tissue and some fibrous connective tissue. No pulp-like tissue characterized by the presence of odontoblast-like cells was observed lining the dentin-like mineralized tissue.