[Fitting of the reconstructed craniofacial hard and soft tissues based on 2-D digital radiographs].

PURPOSE: In this study, we reconstructed the craniofacial hard and soft tissues based on the data from digital cephalometric radiographs and laser scanning. The effective fitting of the craniofacial hard and soft tissues was performed in order to increase the level of orthognathic diagnosis and treatment, and promote the communication between doctors and patients. METHODS: A small lead point was put on the face of a volunteer and frontal and lateral digital cephalometric radiographs were taken. 3-D reconstruction system of the craniofacial hard tissue based on 2-D digital radiograph was used to get the craniofacial hard tissue model by means of hard tissue deformation modeling. 3-D model of facial soft tissue was obtained by using laser scanning data. By matching the lead point coordinate, the hard tissue and soft tissue were fitted. RESULTS: The 3-D model of the craniofacial hard and soft tissues was rebuilt reflecting the real craniofacial tissue structure, and effective fitting of the craniofacial hard and soft tissues was realized. CONCLUSIONS: The effective reconstruction and fitting of the 3-D craniofacial structures have been realized, which lays a foundation for further orthognathic simulation and facial appearance prediction. The fitting result is reliable, and could be used in clinical practice.

[Precision validation of 3-D reconstruction of the craniofacial hard tissues based on 2-D digital radiograph].

PURPOSE: In this study, we validated the precision of 3-D craniofacial reconstruction of hard tissues based on 2-D digital cephalometric radiograph, in order to increase the level of orthognathic diagnosis and treatment, and promote communication between doctors and patients. METHODS: Deformation modeling based on 2-D digital radiograph and CT modeling was performed in 7 volunteers. 64 items were measured which described craniofacial hard tissue structure, intuitive overlapping and objective analysis were conducted. SPSS 17.0 software package was used for paired t test. RESULTS: 58 measurement items were not statistically different. Deformation modeling and CT modeling of the consistency was very high. CONCLUSIONS: Deformation modeling based on 2-D digital radiograph of craniofacial hard tissues is accurate and reliable, and basic deviation was within the allowed range. This 3-D reconstruction system could be used in clinic for diagnosis and operation simulation.

[Development of 3-D reconstruction system of the craniofacial hard tissue based on 2-D digital radiograph].

PURPOSE: In this study, we used data from digital cephalometric radiograph to develop a 3-D craniofacial reconstruction system. The system was developed by Visual C++6.0, VTK on the platform of Windows XP, to increase the level of orthognathic diagnosis and treatment, and promote the communication between doctors and patients. METHODS: A model based on CT images was established as a standard model. Then the 3-D coordinate system was constructal and 64 feature points were set up as the initial feature points. The digital radiograph of the patient was adjusted to accord coordinate system of the model and regulated the feature points of the frontal and lateral cephalograms were regulated as the target feature points. Based on a certain deformation algorithm, deformed the standard model was deformed according to the feature points established in the digital radiograph, then the model of craniofacial hard tissue in patient was achieved. RESULTS: The 3-D model reflecting the actual surface construction of the craniofacial hard tissue was constructed. The 3-D image of the model constructed was lively and clear, which could be rotated and zoomed arbitrarily. CONCLUSIONS: Separated deformation and then fusion, the hard tissue reconstruction break through convention. Occlusal relation essentially rebuilt is carried out. This system could be used in clinic for diagnosis and operation simulation.