Caries, being one of the most common diseases found in humans, irreversibly damages hard dental tissues. The progression of caries leads to pulp disease, and the treatment depends on the degree of caries progression. The final outcome of pulp treatment is pulpectomy. With this conventional therapeutic procedure, the dental pulp is removed from a tooth, which results in devitalization of the tooth. Devitalized teeth are no longer functional units, and are prone to fracture. Pulp - dentin complex is a functional unit of hard dental tissue, dentin, and dental pulp. Odontoblasts, or the pulp cells, create dentin throughout life. The defense mechanism of the pulp is the formation of tertiary dentin. The possibility of stimulating the pulp to secrete tertiary dentin is the principle used for the direct pulp capping. Materials for the direct pulp capping have changed throughout history. However, calcium hydroxide, one of the first materials tested for this purpose, is still used today. With the development of technology, calcium silicate-based materials have been included in clinical practice. With the progress of medicine in the field of molecular diagnostics and therapy, stem cells have also been introduced in clinical practice as growth factors, which are inserted into the root canals using scaffolds. Although this discipline of medicine is only in the phase of clinical studies, blood clots can be used in the revascularization process as scaffolds rich in growth factors, stimulating stem cells to differentiate and proliferate.