ABSTRACT
INTRODUCTION: Histologic studies of teeth from animal models of revascularization/revitalization are available; however, specimens from human studies are lacking. The nature of tissues formed in the canal of human revascularized/revitalized teeth was not well established. METHODS: An immature mandibular premolar with infected necrotic pulp and a chronic apical abscess was treated with revascularization/revitalization procedures. At both the 18-month and 2-year follow-up visits, radiographic examination showed complete resolution of the periapical lesion, narrowing of the root apex without root lengthening, and minimal thickening of the canal walls. The revascularized/revitalized tooth was removed because of orthodontic treatment and processed for histologic examination. RESULTS: The large canal space of revascularized/revitalized tooth was not empty and filled with fibrous connective tissue. The apical closure was caused by cementum deposition without dentin. Some cementum-like tissue was formed on the canal dentin walls. Inflammatory cells were observed in the coronal and middle third of revascularized/revitalized tissue. CONCLUSIONS: In the present case, the tissue formed in the canal of a human revascularized/revitalized tooth was soft connective tissue similar to that in the periodontal ligament and cementum-like or bone-like hard tissue, which is comparable with the histology observed in the canals of teeth from animal models of revascularization/revitalization.
Subject(s)
Apexification/methods , Bicuspid/pathology , Periapical Abscess/therapy , Aluminum Compounds/therapeutic use , Anti-Bacterial Agents/administration & dosage , Blood Coagulation/physiology , Calcification, Physiologic/physiology , Calcium Compounds/therapeutic use , Cementogenesis/physiology , Child , Ciprofloxacin/administration & dosage , Connective Tissue/pathology , Dental Fistula/therapy , Dental Pulp Cavity/pathology , Dental Pulp Necrosis/therapy , Dentin/pathology , Drug Combinations , Female , Follow-Up Studies , Humans , Methylmethacrylates/therapeutic use , Metronidazole/administration & dosage , Minocycline/administration & dosage , Oxides/therapeutic use , Root Canal Filling Materials/therapeutic use , Root Canal Preparation/methods , Silicates/therapeutic use , Tooth Apex/pathology , Zinc Oxide-Eugenol Cement/therapeutic useABSTRACT
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.