Three-dimensional bioprinting using a coaxial needle with viscous inks in bone tissue engineering - An In vitro study

Abstract

Introduction: Vascularized autologous tissue grafts are considered “gold standard” for the management of larger bony defects in the craniomaxillofacial area. This modality does however carry limitations, such as the absolute requirement for healthy donor tissues and recipient vessels. In addition, the significant morbidity of large bone graft is deterrent to fibula bone flap use. Therefore, less morbid strategies would be beneficial. The purpose of this study was to develop a printing method to manufacture scaffold structure with viable stem cells. Materials and Methods: In total, three different combinations of ground beta tri-calcium phosphate and CELLINK (bioinks) were printed with a nozzle to identify a suitable bioink for three-dimensional printing. Subsequently, a coaxial needle, with three different nozzle gauge combinations, was evaluated for printing of the bioinks. Scaffold structures (grids) were then printed alone and with additional adipose stem cells before being transferred into an active medium and incubated overnight. Following incubation, grid stability was evaluated by assessing the degree of maintained grid outline, and cell viability was determined using the live/dead cell assay. Results: Among the three evaluated combinations of bioinks, two resulted in good printability for bioprinting. Adequate printing was obtained with two out of the three nozzle gauge combinations tested. However, due to the smaller total opening, one combination revealed a better stability. Intact grids with maintained stability were obtained using Ink B23 and Ink B42, and approximately 80% of the printed stem cells were viable following 24 hours. Discussion: Using a coaxial needle enables printing of a stable scaffold with viable stem cells. Furthermore, cell viability is maintained after the bioprinting process.

Additive Manufactured Polymers in Dentistry, Current State-of-the-Art and Future Perspectives-A Review

“…3D bioprinting in dentistry and maxillofacial surgery is currently involved in manufacturing soft and hard tissue structures for application in periodontal [170][171][172], periodontal ligament (PDL) [173,174], dental tissue [175][176][177][178], dental pulp [68,179,180], dentin [68,179,181], bone [182][183][184][185][186][187][188][189][190][191][192][193][194][195], and alveolar bone [182,183,196,197] regeneration, as well as head and neck cancer in vitro models [198] (Table 2).…”

Functional engineering strategies of 3D printed implants for hard tissue replacement

“… Multi-material bioprinting based on microextrusion technologies with multiple printing-heads [ 245 , 357–359 ]. ( A : Coaxial nozzles were design for gird construct with inner/outer layers.…”

“…Reproduced with permission from Ref. [ 357 ] Copyright 2020 Wolters Kluwer. B : The design of microfluidic printheads with multiple inlets and an outlet, and the color-coded heterogenous construct.…”

Triaxial bioprinting large-size vascularized constructs with nutrient channels

“…It can directly form a nutritional channel during printing without extra design for construction [15,16]. Additionally, depending on the specific application or design, cell-loaded bioinks, sacrificial materials, and crosslinking agents can all be used as precursors for bioprinting [16][17][18][19][20][21][22]. However, due to that coaxial bioprinting only contains two layers, it is difficult to simultaneously achieve precise loading of multiple types of cells and maintain microfluidic channels.…”