Fabrication of customized anatomical-shaped bone tissue engineering scaffolds with reverse engineering and rapid prototyping technology

Huanwen DING; Zhongyue ZHAO; Chunlei TANG; Pingyue LI; Yingjun WANG; Qingshui YIN

ABSTRACT

BACKGROUND:

The rudiment of tissue engineering is to obtain tissue from patients. The cells are expanded into a population through cellular culture, and seeded into scaffolds, which can accommodate and guide the growth and proliferation of new cells in the three-dimensional scaffolds. At last, the constructed tissue is transplanted in vivo to repair or replace damaged or diseased tissues. Afterward neovascularization of the graft, the scaffolds are absorbed gradually. Finally, the new tissue replaces completely the damaged or diseased tissues

OBJECTIVE:

To evaluate the feasibility of designing and fabricating customized anatomical-shaped bone tissue-engineering scaffolds with reverse engineering and rapid prototyping (RP) techniques. To avoid the disadvantage of the conventional fabricated methods of the scaffolds.

DESIGN:

The method of fabricating customized anatomical-shaped bone tissue engineering scaffolds.

SETTING:

Computer-aided design (CAD) of the scaffold was conducted in CAD training center, Guangdong Machinery Research Institute. Rapid prototyping fabrication of the scaffold was conducted in Guangdong Longchuangyu Limited Cooperation. The scaffold was fabricated by sterophotocureable technology and was made of photosensitized resin.

METHODS:

This experiment was carried out at the Center of Department of Traumatic Orthopedics, General Hospital of Guangzhou Military Area Command of Chinese PLA from October 2004 and January 2005. According to reverse engineering, layered image information of skeleton of the patients was scanned with CT/MRI. Anatomical models of region of interesting were created by means of CT or MRI three-dimensional reconstruction and surface reconstruction. The internal construction of the scaffolds was designed with CAD software in the outline of the anatomical models to develop computer-aided model. The prototypes of the scaffolds were fabricated by RP process.MAIN OUTCOME

MEASURES:

①CT/MRI scanning, three-dimensional reconstruction, anatomical modeling; ② computer-aided design of customized bone tissue engineering scaffolds; ③rapid prototyping fabrication of customized bone tissue engineering scaffold.

RESULTS:

①Anatomical models of bone joint were established through CT/MRI three-dimensional reconstruction. ② The internal structure of the scaffold was designed to establish the entity model of bone tissue engineering scaffold successfully with computer-aided design software. ③ CAD model of bone tissue engineering scaffold guided prototypes to develop the customized anatomical-shaped bone tissue engineering scaffolds. The internal structure of bone tissue engineering scaffold was fine and had high degree of porosity-and pore interconnectivity.

CONCLUSION:

Customized anatomical-shaped bone tissue engineering scaffolds can be fabricated with reverse engineering and RP technology. Among all RP processes, stereophotocureable technology (SLA) is the best one with good precision, smooth surface and good shaping.