Fig. 2

Methodology done in the current study. Upper panel (A): tissue harvesting and decellularization and P-ECM hydrogel preparation. (a) bovine mandibular molar teeth were immediately extracted; (b&c) bovine pulp tissues were extirpated, cut into equal pieces and decellularized using trypsin/EDTA, Dnase I and subsequent washes with PBS and deionized water; (d) decellularized pulp tissue ready for lyophilization; (e) lyophilized P-ECM after grinding; (f) digestion of tissues in pepsin/HCl for 24 h on stirrer; (g) pre-gel solution loaded in 24-well plate; (h) hydrogel with a concentration of 3 mg/mL after gelation; (Insert) in (h) showing injectability of P-ECM hydrogel. Middle panel (B): regenerative endodontic procedures in a canine dog infected tooth model. (i) access cavity preparation, extirpation of pulp tissue and induction of apical periodontitis; (j) follow up digital radiograph to confirm the formation of periapical lesions; (k&l) disinfection protocol and intracanal medicament placement for 2 weeks and IRM placement; (m) injection of hydrogels (P-ECM or HA) or injection of i-PRF; (n) MTA plug placement; (o) post operative digital radiograph confirming the coronal seal by MTA plug and resin modified GIC. Lower panel (C): diagrammatic illustration showing (1) The modification of the occlusal table of double-rooted premolars, (2) Access cavity preparation, extirpation of pulp tissue and induction of apical periodontitis, (3) Disinfection protocol and intracanal medicament placement for 2 weeks followed by either, (4) Injection of hydrogels (P-ECM, HA or i-PRF) or, (5) Induction of blood clot to fill the canal, (6) Coronal seal by MTA plug and resin modified glass ionomer cement