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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Animals, Bicuspid, Cell Adhesion, Cell Differentiation, Cell Proliferation, Cell Shape, Dental Pulp, Dental Pulp Cavity, Dentin, Extracellular Matrix Proteins, Female, Fibrin Tissue Adhesive, Humans, Integrin-Binding Sialoprotein, Neovascularization, Physiologic, Odontoblasts, Phosphoproteins, Rats, Rats, Sprague-Dawley, Regeneration, Root Canal Preparation, Sialoglycoproteins, Subcutaneous Tissue, Tissue Scaffolds, Tooth, Nonvital.
user
Does fibrin gel improve tissue ingrowth and cell differentiation in human immature premolars implanted in rats? Context: In pulpless immature human premolars implanted in rodents, this study investigated whether fibrin gel offered advantages over leaving the root canal empty regarding soft tissue ingrowth and cell differentiation. Root canals of extracted human immature premolars (n = 12) were accessed and then irrigated with 5% sodium hypochlorite followed by 17% ethylenediaminetetraacetic acid. Root canals were then either left empty or filled with a fibrin gel (n = 6 each) before being placed subcutaneously on top of the calvarial bone of rats (1 tooth per rat) for 12 weeks. After sacrifice, teeth were histologically assessed. Tissue ingrowth was quantified and compared between groups using the Mann-Whitney U test (P < .05). Cells adhering to the pulp canal wall were immunohistochemically screened for the presence of bone sialoprotein (BSP) and dentin sialoprotein (DSP). More tissue grew into the pulp space when teeth were filled with fibrin gel (P < .05). The presence of fibrin gel affected not only the extent of tissue ingrowth but also tissue morphology and differentiation of cells contacting the dentinal wall. In the fibrin gel group, newly formed tissue was similar to normal pulp, constituted of inner pulp, cell-rich zone, cell-free zone, and an apparent odontoblast layer, which stained positive for BSP and DSP. Newly formed blood vessels were also more abundant compared with the initially empty root canals.
assistant
Under the conditions of this study, fibrin gel improved cell infiltration and cell-dentin interaction. Both are necessary for pulp tissue regeneration. Final Decision: yes