CHONGQING, Aug. 4 -- Chinese researchers and companies are developing the technology and processes to make 3D-printed skin a reality, and they expect to achieve this within two to three years.

Wu Jun, director of the Burns Institute at the Southwest Hospital in Chongqing, said he has been testing the process with pig skin.

"In printing skin, the biggest challenge is the 'ink.' We need to find the right material that can be made into a certain form while not damaging its activity," he said. The ink he refers to is the skin tissue, at the current time, 3D printing in the medical industry mostly produces hard items, the flexibility of skin makes this process more difficult.

"I expect the process to be finalized within two to three years," he said.

"Many other researchers are at the same stage as us, so we are moving fast to be the first to make this breakthrough," he said.

The aim is to make custom-made skin for burns patients that will be printed according to their wounds.

3D printing has been used in many operations, but there are still a few more years to go until we can successfully print live tissue or organs, Wu said.

Some researchers across the globe have printed small tissue samples in a lab environment, but the challenge is to keep it alive, functional and fit for clinical use, he said.

There is a 3D printing factory for medical products under construction in Chongqing, said Yang Chen, manager of Hkable Biological 3D (China) Co. Ltd.

The factory, a joint venture between U.S.-based Hkable and Chinese biotechnology company Jintai in Chongqing, is the first 3D medical printing factory in China.

"We will use 3D printers to make splints and artificial limbs in the beginning, then we will develop more advanced stem cell-printed products," Yang said.

Across China, there have been a number of successes using 3D printing for surgical purposes.

In June, doctors in Peking University Third Hospital replaced five vertebrae with 3D-printed replicas in a cancer patient. The 3D-printed vertebrae measured 19 centimeters, the longest ever in a successful operation.

"3D printing is changing medicine," said Dai Kerong, an academic with the Chinese Academy of Engineering.

"Mass-produced joints do not fit every patient, there is a need for custom-made 3D printed joints," he said.

"This is only the beginning, however, we must make sure 3D medical applications are properly supervised," said Dai.