The computer-aided design and manufacturing of individualized miniscrew surgical guides based on a high-precision three-dimensional integrated digital maxillodental model / 中国组织工程研究

BACKGROUND: Surgical guides designed based on a three-dimensional cone-beam CT (CBCT) model have been reported. However, CBCT cannot remodel fine soft tissue such as gums, and it can only be used to design a simple dental retainer with relatively poor stability. OBJECTIVE: To establish a high-precision three-dimensional (3D) integrated maxillodental model by matching CBCT model with 3D digital maxillodental model using 3D automatic registration method, based on which, we designed and manufactured individualized miniscrew surgical guides. METHODS: CBCT maxillodental models and laser-scanned dentition models obtained from six malocclusion cases were matched and overlapped using the 3D automatic registration method to fabricate the 3D integrated maxillodental model. Then, we accurately positioned and virtually implanted a micro-implant into the 3D integrated maxillodental model. Subsequently we prepared a high-precision individualized resin surgical guide by rapid prototyping technology. The inner diameter of the guide track was detected by a vernier caliper. Patients tried on the resin surgical guide, and then occlusion condition, guide seating and retention were detected. RESULTS AND CONCLUSION: Due to the high-precision registration of the model, all the resin surgical guide plates were suitable. The plate retention was enhanced after tooth clinching, and all the patients felt comfort when wearing the surgical guide plate, with no compression or other discomforts. The inner diameter of the guide track was (1.79±0.23) mm, and the measurement error was not statistically significant (P >0.05). These findings demonstrate that the high-precision surgical guide plate based on the high-precision 3D integrated model can provide the foundation for further investigations on the clinical application of surgical guides.

Cloning of human bone morphogenetic protein-2 gene and the construction of its eukaryotic expression vector / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To clone human bone morphogenetic protein-2 (hBMP2) gene and construct its eukaryotic expression vector pcDNA3.1 -hBMP2.</p><p><b>METHODS</b>Human BMP2 gene was amplified by RT-PCR method from human osteosarcoma cells and constructed into eukaryotic expression vector pcDNA3.1-hBMP2. The gene in the vector pcDNA3.1-hBMP2 was identified by PCR amplification, enzyme digestion and DNA sequencing.</p><p><b>RESULTS</b>The cloned DNA was confirmed to be hBMP-2 gene.</p><p><b>CONCLUSION</b>In this study, hBMP2 gene is successfully cloned and its eukaryotic expression vector pcDNA3.1-hBMP2 is constructed, which provides the foundation of using BMP2 gene therapy to accelerate new bone formation in distraction osteogenesis.</p>