Introduction
Nasal cartilage is a specific connective tissue of hyaline type, without nerves, vessels and lymph, and has a very low number of cells. This tissue consists of approximately 1% chondrocytes and 99% extracellular matrix (ECM), and its chondrocytes originate from mesenchymal stem cells [
1]. Cartilage ECM is mainly composed of water, macromolecules and proteoglycans, and is the product and the host of chondrocytes at the same time [
3]. These features cause special mechanical properties and low self-healing capacity. Currently, the common and gold standard treatment is reconstruction using local flap or autologous cartilage transplantation (ACI) [
1,
4]. The ACI surgery for major nasal reconstruction is a complex, time-consuming and skill-based procedure that involves harvesting rib cartilage, cutting and manually suturing them into the nose-shaped framework. The duration of the surgery can be more than 8 hours, during which the patient is under general anesthesia [
4]. Due to the lack of septal cartilage, a modified autologous costal cartilage is usually used for grafting [
2]. The purpose of cartilage tissue repair is to restore the key properties of native hyaline cartilage from the histological and biomechanical point of view.
In recent years, medical engineering applications for nasal cartilage have been rapidly developed [
6, 7]. Bioprinting is an interdisciplinary science between medical sciences, biology, mechanical engineering and material science, and it is also known as a new approach in tissue engineering [
12, 13]. As one of the branches of 3D printing, bioprinting technology is based on the precise placement of living cells and biomaterials to create replacement tissues based on the specific geometric and functional requirements of each tissue, with similar functions and properties. Bioprinting, in addition to avoiding complications of the donor area and personalization, has created unique opportunities for cartilage repair and reconstruction [
4,
14]. This technology enables the printing of constructs with small and fine details up to dimensions with several hundreds of nanometers [
15]. Today, it is also possible to simultaneously deposit two or more biological substances and produce complex and personalized constructs based on the patient’s medical images [
21].
Bioprinting has been able to overcome many limitations of tissue engineering, such as accurate cell distribution and tissue biological function; however, there are challenges in nasal cartilage reconstruction with bioprinting. One of the most important challenges is the unavailability of appropriate bioinks [
18,
22]. This study aimed to investigate the ability of different three-dimensional bioprinting methods to repair defects in the nose area. In this regard, the studies with on nasal cartilage bioprinting, related technologies and its process were reviewed.
Methods
This is a review study. The search for related articles was done in ScienceDirect, Springer, Wiley, Cambridge, DeGruyter and Google Scholar databases using the keywords tissue engineering, nasal cartilage, 3D bioprinting, and bioink materials and with a time limit of 4 years. Out of 300 articles, 159 were finally included for the review.
Results
The review of studied showed that, in order to obtain the desired results in vitro or in vivo, choosing the appropriate bioprinting approach and biological ink has a major role. The most important studies with in-vitro tests are listed in
Table 1.
Table 2 shows the studies with in-vivo tests.

The presented findings related to 3D bioprinting technologies included the processing method, extrusion method, inkjet method, laser method, application in the field of nasal cartilage, characteristics of nasal cartilage, nasal cartilage implantation, 3D modeling, bio ink, bio materials, cell sources, bioactives, in-vitro evaluations, and in-vivo evaluations.
Conclusion
Until recently, cartilage tissue regeneration methods were limited to the use of autologous or allogeneic cartilages or the use of alloplastic grafts, each of which had inevitable disadvantages. For this reason, bioprinting is used to solve these problems in regenerative medicine. According to the specific requirements of the bioinks of the target tissues, researchers have used different technologies for tissue and organ printing, each of which has advantages and limitations. Based on the in-vivo and in-vitro studies that have been carried out on the printed nasal cartilage tissues, bioprinting technology has been able to imitate the cartilage host tissue to a very acceptable extent in terms of morphological, biochemical and mechanical aspects. Although the use of this technology at the clinical level still faces limitations, the prospect of this technology is promising since it can address nasal defects with low cost, unique accuracy and personalization.
Ethical Considerations
Compliance with ethical guidelines
This article is a meta-analysis with no human or animal sample.
Funding
This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors.
Authors' contributions
Conceptualization, study design, data acquisition, analysis and curation: Fatemeh Toosizadeh Khorasani and Hosein Rostamani; Statistic analysis and initial draft preparation: Hosein Rostamani; Review and editing: Omid Fakhraei and Narges Kelidari; Supervision: Omid Fakhraei.
Conflicts of interest
The authors declared no conflict of interest.
Acknowledgements
The authors would like to thank Department of Medical Engineering, Islamic Azad University, Mashhad Branch, Iran, Mashhad for accompanying in this research.