Recent Advances in 6D Printing and Future Prospects for Biomedical Applications.

Abstract

A significant advancement in additive manufacturing, the switch from 3D to 6D printing opens up new avenues for biomedical innovation. Traditional 3D printing makes simple models, but it cannot precisely create very complicated shapes that are needed for advanced medical devices. Even if later developments, such as 5D printing with multi-axis fabrication and 4D printing with stimulus-responsive materials, have increased structural strength and design flexibility, they are still unable to produce completely autonomous, patient- responsive systems. Multi-axis construction and intelligent, reprogrammable materials that can sense, react, and adjust to physiological stimuli like pH, temperature, enzymes, and mechanical stresses are novelly combined in 6D printing. Owing to its special capabilities, positioned as a game-changing technology for next-generation biomedical devices, enabling dynamic drug delivery platforms, adaptive prosthetics, and selfhealing orthopedic systems that exceed previous manufacturing techniques. With limitations such as a lack of multi-responsive materials, difficulties in producing it on a large scale, and complicated regulations, it is prevented from being widely used. This article explores novel applications of 6D printing, along with its technological merits over 3D-5D methods, and provides insights towards the development of bio-hybrid, effective, and clinically relevant outcomes in the biomedical field, including regenerative medicine and tissue engineering.