In recent years, the number of publications involving the development of 3D printing for dental applications has increased significantly due to the possibility that this area offers to generate individualized products and improve oral and craniofacial regeneration. These approaches can be developed using biomaterials and growth factors that seek to induce tissue formation through stimulating specific cellular functions in vitro and in vivo [1,2].
Craniofacial tissues - bones, teeth, cartilage, muscles, and ligaments - form complex systems responsible for ensuring the smooth functioning of a series of vital functions in the body, such as critical speech, digestion, and breathing. These tissues are organized with complex 3D architectures and specific cell-cell interactions, which hinders the total recovery of craniofacial tissues exposed to trauma or congenital malformations. Conventional recovery strategies still fail to promote widely efficient results, making 3D bioprinting an excellent candidate to mimic the complexity and multicellular interactions in these tissues .
Figure 1: Schematic representation of possible applications of 3D printing in dentistry .
Scaffolds are essential for obtaining functional tissues since they provide structural support that stimulates fixation, proliferation, and differentiation. In dental applications, scaffolds associated with stem cells from dental pulp or periodontal ligament are being developed to regenerate alveolar bone and periodontal tissue. With this purpose, biodegradable synthetic polymers are often used in combination with bioceramics in the dentistry field .
Recently, Sharma et al. elaborated an overview of the different types of biomaterials used for dental regeneration and nanotechnology in the design of bioactive scaffolding. The authors highlighted the importance of combining different types of materials to meet the requirements of the tissue in terms of porosity, surface area, and mechanical resistance. This is important because different materials present specific limitations, such as poor mechanical properties and lack of control over pore size in natural scaffolds, and low cell adhesion in synthetic ones; thus, combining the two types of scaffold allows to increase the performance of the material [3,4].
In 2019, Han et al. used bioprinting technology to produce a 3D dentin-pulp complex with patient-specific shape, inducing localized differentiation of human dental pulp stem cells within a single structure. A fibrin-based bioink was used for bioprinting the dental pulp stem cells. After culture with a differentiation medium for 15 days, the results indicated success in localized differentiation of stem cells in the external region of the 3D cell construct, demonstrating the possibility of producing patient-specific composite tissues through 3D bioprinting .
Figure 2: The process of bioprinting patient-specific shaped 3D dentin–pulp complexes .
1- Oberoi, G., Nitsch, S., Edelmayer, M., Janjić, K., Müller, A. S., & Agis, H. (2018). 3D Printing—Encompassing the Facets of Dentistry. Frontiers in Bioengineering and Biotechnology.
2- Obregon, F., Vaquette, C., Ivanovski, S., Hutmacher, D. W., & Bertassoni, L. E. (2015). Three-Dimensional Bioprinting for Regenerative Dentistry and Craniofacial Tissue Engineering. Journal of Dental Research.
3- Rodriguez-Salvador, M., & Ruiz-Cantu, L. (2018). Revealing emerging science and technology research for dentistry applications of 3D bioprinting. International journal of bioprinting
4- Sharma, S. (2014). Biomaterials in Tooth Tissue Engineering: A Review. Journal of clinical and diagnostic research.
5- Han, J., Kim, D. S., Jang, H., Kim, H.-R., & Kang, H.-W. (2019). Bioprinting of three-dimensional dentin–pulp complex with local differentiation of human dental pulp stem cells. Journal of Tissue Engineering.