| In clinic, traditionally facial prosthesis has been made by way of handworked sculpted wax pattern for thousands of years, which is not advanced enough to meet the practical needs of emulation. This study applied the reverse engineering and rapid prototyping techniques in the field of facial defect restoration, focusing on 3 main facial defect types, in terms of unilateral orbital defect, unilateral ear-lost case and nasal defect. This study tried to fulfill the 3-dimentional (3D) emulational design and the related research of individualized rapid manufacture.According to the practical differences of the facial organ defects, this research adopted 3 different advanced approaches of the reverse 3D measurement, which obtained the ideal reconstructed 3D models.1. As to the orbital and the nasal areas, which are complanate and have no obvious undercut, it is more suitable to scan the plaster model of the organ through a 3D laser scanner, from which can get a most precise result (?. 01mm).2. As to the serious face defect, such as the nasal majority-lost case, it is more effective to use the spiral CT scanner to scan the vivo parenchyma. This method can avoid the interferences of the tissue undercut and the error of the plaster duplicated model. The result showed a satisfied reconstructive digital model.3. The lay-milled graphic technique, the most advanced 3D sectionmeasurement approach, is firstly adopted by this research in the field of facial prosthesis. This technique can get all the data of inside and outside contour of the objective in any shape without being influenced by undercut areas. In the experiment an auricle plaster model was measured precisely (?. 05mm).Each of these methods has its own advantages and disadvantages. This research adopted them flexibly according to the different motivations and various objectives to get the ideal organ digital impression in the experiments.On the base of the digital impression got from reverse measurements, according to the symmetrical feature of man's facial organs, CAD software used the 3D digital model to reverse patient's normal tissue data and got the defect tissue data by changing the corresponding dimensional coordinate. This method successfully fulfilled the emulational prosthesis design of unilateral orbital defect, unilateral ear-lost case and nasal defect.This research proposed a new project of virtual nasal design. Firstly, it built up a 3D digital database of normal noses of Chinese people. (This research section was completed by other members in this group.) Then, the appropriate normal nose model that matched the features of defect nose could be transferred from the database. Then, on a special 3D software platform, the normal nose models could be compared with the patient's facial modal one by one. Next, the suitable nasal model would be adjusted carefully and precisely in order to obtain a satisfied effect on the screen. Finally, the digital data of the suitable normal nasal model and the digital facial model could be syncretized smoothly to get the final design of the nasal prosthesis. It is the first time in the world to put forward a completed design of the project aiming at the nasal majority-lost cases. The result achieved in this research would have a comprehensive usage in the future.This research employed the rapid prototyping system which was based on the tridimensional printing approach. In the experiments, the rapid prototyping equipments could directly and precisely transform the STL data model of the organ prosthesis into the resin pattern,realizing the individualized prosthesis manufacture rapidly and precisely.This dissertation carried on two clinical researches and evaluated the results of a nasal defect case and a unilateral ear-lost case. Since that the prosthesis was made based on the information of patient's own organ, it repristinated the patient's face in a preferable condition. The clinical results showed that this technique could realize the emulational prosthesis design successfully. It also...
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