[Application of digital design and three-dimensional printing technique on individualized medical treatment].

OBJECTIVE: To summarize the latest research development of the application of digital design and three-dimensional (3-D) printing technique on individualized medical treatment. METHODS: Recent research data and clinical literature about the application of digital design and 3-D printing technique on individualized medical treatment in Xi'an Jiaotong University and its cooperation unit were summarized, reviewed, and analyzed. RESULTS: Digital design and 3-D printing technique can design and manufacture individualized implant based on the patient's specific disease conditions. And the implant can satisfy the needs of specific shape and function of the patient, reducing dependence on the level of experience required for the doctor. So 3-D printing technique get more and more recognition of the surgeon on the individualized repair of human tissue. Xi'an Jiaotong University is the first unit to develop the commercial 3-D printer and conduct depth research on the design and manufacture of individualized medical implant. And complete technological processes and quality standards of product have been developed. CONCLUSION: The individualized medical implant manufactured by 3-D printing technique can not only achieve personalized match but also meet the functional requirements and aesthetic requirements of patients. In addition, the individualized medical implant has the advantages of accurate positioning, stable connection, and high strength. So 3-D printing technique has broad prospects in the manufacture and application of individualized implant.

Low-intensity pulsed ultrasound accelerates tooth movement via activation of the BMP-2 signaling pathway.

The present study was designed to determine the underlying mechanism of low-intensity pulsed ultrasound (LIPUS) induced alveolar bone remodeling and the role of BMP-2 expression in a rat orthodontic tooth movement model. Orthodontic appliances were placed between the homonymy upper first molars and the upper central incisors in rats under general anesthesia, followed by daily 20-min LIPUS or sham LIPUS treatment beginning at day 0. Tooth movement distances and molecular changes were evaluated at each observation point. In vitro and in vivo studies were conducted to detect HGF (Hepatocyte growth factor)/Runx2/BMP-2 signaling pathways and receptor activator of NFκB ligand (RANKL) expression by quantitative real time PCR (qRT-PCR), Western blot and immunohistochemistry. At day 3, LIPUS had no effect on the rat orthodontic tooth movement distance and BMP-2-induced alveolar bone remodeling. However, beginning at day 5 and for the following time points, LIPUS significantly increased orthodontic tooth movement distance and BMP-2 signaling pathway and RANKL expression compared with the control group. The qRT-PCR and Western blot data in vitro and in vivo to study BMP-2 expression were consistent with the immunohistochemistry observations. The present study demonstrates that LIPUS promotes alveolar bone remodeling by stimulating the HGF/Runx2/BMP-2 signaling pathway and RANKL expression in a rat orthodontic tooth movement model, and LIPUS increased BMP-2 expression via Runx2 regulation.

Clinical analysis of 194 cases of head and neck hamartoma.

OBJECTIVE: The aim of this study was to analyze the clinical management of hamartomas in the head and neck region (HNH). STUDY DESIGN: From January 1996 to December 2011, a retrospective analysis of 194 patients with HNH was performed. The preoperative examinations, surgical treatment, and prognosis were recorded and analyzed. RESULTS: Of the 194 patients, 107 were male and 87 female. Their ages ranged from 1 month to 82 years with a mean of 33 years. The most common locations were the oral mucosa (68.6%) and head and neck skin (27.3%). The course of disease ranged from 1 to 264 months with a mean of 66 months. Routine laboratory examinations were within normal limits. All patients underwent surgical removal of the lesions and prognosis was good. CONCLUSIONS: The clinical characteristics of HNH are not specific, and the clinical manifestation is always the same for benign tumors. The first choice of treatment is surgical excision, which results in a good prognosis.

Individually Prefabricated Prosthesis for Maxilla Reconstruction.

The reconstruction of maxillofacial bone defects by the intraoperative modeling of implants may reduce the predictability of the esthetic result, leading to more invasive surgery and increased surgical time. To improve the maxillofacial surgery outcome, modern manufacturing methods such as rapid prototyping (RP) technology and methods based on reverse engineering (RE) and medical imaging data are applicable to the manufacture of custom-made maxillary prostheses. After acquisition of data, an individual computer-based 3D model of the bony defect is generated. These data are transferred into RE software to create the prosthesis using a computer-aided design (CAD) model, which is directed into the RP machine for the production of the physical model. The precise fit of the prosthesis is evaluated using the prosthesis and skull models. The prosthesis is then directly used in investment casting such as "Quick Cast" pattern to produce the titanium model. In the clinical reports presented here, reconstructions of two patients with large maxillary bone defects were performed using this new method. The custom prostheses perfectly fit the defects during the operations, and surgery time was reduced. These cases show that the prefabrication of a prosthesis using modern manufacturing technology is an effective method for maxillofacial defect reconstruction.

Individually Prefabricated Prosthesis for Maxilla Reconstuction.

The reconstruction of maxillofacial bone defects by the intraoperative modeling of implants may reduce the predictability of the esthetic result, leading to more invasive surgery and increased surgical time. To improve the maxillofacial surgery outcome, modern manufacturing methods such as rapid prototyping (RP) technology and methods based on reverse engineeing (RE) and medical imaging data are applicable to the manufacture of custom-made maxillary prostheses. After acquisition of data, an individual computer-based 3D model of the bony defect is gernerated. These data are tranferrred into RE software to create the prosthesis using a computer-aided design (CAD) model, which is directed into the RP machine for the production of the physical model. The precise fit of the prosthesis is evaulated using the prosthesis and skull model. The prosthesis is then directly used in investment casting such as "Quick Cast" pattern to produce the titanium model. In the clincical reports presented here, reconstructions of two patients with large maxillary bone defects during the operations, and surgery time was reduced. These cases show that the prefabrication of a prosthesis using modern manufacturing technology is an effective method for maxillofacial defect reconstruction.