The management of traumatized immature permanent teeth is a major challenge, considering that they are characterized by wide canals with thin walls, large pulp chambers, and divergent apical roots. For many years, apexification was the therapy for necrotic immature permanent teeth. However, this procedure translates into fragile dental elements with low longevity in the oral cavity (Alghutaimel et al., 2021, Bracks et al., 2019). Nowadays, regenerative endodontic procedures (REP) have expanded their initial indication for treatment of necrotic immature permanent teeth. These approaches are based on tissue engineering principles, including cells, scaffolds and appropriate signaling molecules, which are critical for the regenerative endodontic process (Alghutaimel et al., 2021). Stem cells are a source of easy access described by pulp revascularization therapies through evoked bleeding, while dentin is a rich source of different growth factors such as TGF-β and VEGF (Bracks et al., 2019). Different scaffold proposals have been carried out, including native, artificial or hybrid scaffolds. Some biomaterials have already been tested as scaffolds for regenerative endodontics, such as type 1 collagen, hyaluronic acid hydrogels, chitosan-based hydrogel and self-assembly peptides, among others (Alghutaimel et al., 2021, Sousa et al., 2022). However, they can fail to mimic pulp conditions favorable to cell differentiation and proliferation (Song et al., 2017). This is an important point, as the use of a material that mimic the pulp or approximate of your composition can be favorable to induce more appropriate conditions to tissue regeneration.

Another alternative for REPs is the use of extracellular matrices (ECM) from decellularized human dental pulp (Setiawati, Nguyen, Jung & Shin, 2018). Promising results were observed in the development of a decellularized biological scaffold derived from dental pulp with the preservation of extracellular structural components necessary for specific pulp tissue regeneration. These biomaterials actively participate in and support cellular chemotaxis and function to achieve pulp regeneration, with immunohistochemical characteristics identical or similar to actual pulp tissue (Matoug-Elwerfelli et al., 2018). This is an important step towards providing cells with the ideal environment to support the regeneration of the dentin-pulp complex. Song et al. (2017) were the first to demonstrate the decellularization of human tooth slices (Song et al., 2017). A year later, Matoug-Elwerfelli et al. (2018) performed an entire human dental pulp decellularization (Matoug-Elwerfelli et al., 2018). Although both studies were important to generate decellularized pulp tissues, different protocols were used. For this process to act as a potential biological scaffold, in addition to presenting a successful decellularization protocol, preserving proteins that play an important role in regenerative mechanisms is essential (Li et al., 2020).

Therefore, a comparative characterization of both described decellularization protocols can support the identification of remaining proteins, since the maintenance of proteins and growth factors are linked to active mechanisms in the regenerative process. Thus, as the literature presents two established protocols that have demonstrated decellularization, analyzes such as proteomics can verify the feasibility of this use in relation to the preservation of these factors, since this discussion has not been reported in the literature. Furthermore, comparative analysis can support the choice of methods for future applications in this field. For this purpose, a comparative histological and proteomic analysis by nanoscale mass spectrometry of two decellularization protocols previously described by Matoug-Elwerfelli et al. (2018) and Song et al. (2017) were performed, to evaluate the biotechnological potential of ECM as an alternative for biological scaffold in regenerative endodontics.