ABSTRACT
BACKGROUND:In recent years, many manufacturing techniques have been recently developed for soft tissue engineering scaffolds. Especialy additive manufacturing with a unique material accumulated forming principle can be feasible and reliable to manufacture the highly precise scaffolds with gradient structures and multi-materials for large soft tissue defect repairing. OBJECTIVE:To summarize scaffolds manufacturing technologies in the soft tissue engineering applications developed in recent years and to predict the direction of development. METHODS: A retrieval was performed for the literature about the manufacturing methods of soft tissue scaffolds using key words of “additive manufacturing, microfabrication, vascular tissue engineering, muscle tissue engineering, cartilage tissue engineering, stereolithography, 3D printing, biodegradable hydrogel” in English and Chinese, which were published between January 2010 and September 2013 in PubMed Database and China National Knowledge Infrastructure (CNKI) Database. RESULTS AND CONCLUSION:For large soft tissue defects repairing, structure design of the scaffolds has been shifted from a simple planar structure to a more complex three-dimensional structure, and integration of scaffold structure, materials and cels, and growth factors during the manufacturing procedure can be used to obtain the resolution of vascularization. Additive manufacturings become one of the most promising approaches for the ideal soft tissue scaffolds with gradient and complex structure and multi-materials. In particular, the hydrogel/cellcomposite scaffolds fabrication, a hot but promising approach to develop the soft tissue engineering wil be made progress by the accurate principles and processes of the hydrogel additive manufacturing combined with the introduction of living cels and growth factors.
ABSTRACT
@# Objective Due to the problem of individual matching, exclusivity and loose with pure mechanical fixation for artificial hemi-knee joints made by traditional method, a new manufacturing process based on rapid prototyping technique and custom-made concept is presented.MethodsRapid prototyping was processed to rapidly and accurately shape the prototype of an artificial implant almost with the same shape as the hemi-knee joint of the patient, and the process based on Titanium alloy centrifugal casting technology and biomaterial sintering molding technology was used to fabricate the artificial hemi-knee joint and bioactive proximal tibia artificial bone, respectively.Results and ConclusionThe custom-made knee joint prosthesis has been fabricated and put into clinical use successfully. In comparison with the traditional implants, this system can realize the well matching movement between the artificial hemi-knee joint and its opposite. Meanwhile,the design of functional holes and tibial nails realizes the combination of biological fixation with mechanical fixation for the artificial implant,and the use of bioactive artificial bone promotes bone growth and minimizes the exclusive reaction.