Computer-Aided Design ; Dental Prosthesis Design ; methods ; Humans ; Oral Medicine ; methods ; Research Design ; Technology, Dental ; methods

OBJECTIVETo study the stability and the reliability of the first 3D laser cranio-maxillofacial reconstruction system in China.

METHODSThe same 3D laser scan image of a head plaster model was measured twice three weeks before and after. That head cast was also scanned and reconstructed twice three weeks before and after, and then the 3D images were measured. To the same head cast we compared the laser measurement with the direct manual measurement. The statistical analysis of measurements was made using the paired t test.

RESULTSThere was no significant difference between two sets of measurements on the same image (P > 0.05). The difference in the measurements was not significant between two reconstructed images of the same model (P > 0.05). And there was also no significant difference between the measurements by laser and by hand (P > 0.05).

CONCLUSIONSThe recognition of the author to the 3D laser scan image is reliable. The laser scanning system has a good stability and reliability and can be used in clinical study preliminary.

Cephalometry ; methods ; Facial Bones ; anatomy & histology ; Humans ; Imaging, Three-Dimensional ; methods ; Lasers ; Maxilla ; anatomy & histology ; Orthodontics ; methods ; Reproducibility of Results ; Skull ; anatomy & histology

OBJECTIVETo develop a dental CAD/CAM system with the autonomic intellectual property.

METHOD28 standard teeth crowns were scanned using a newly 3-D laser scanner. As a development platform the Matlab 5.3 were used to process the acquired data, also be used to define the characterized areas on the surfaces of the crowns and to change the crowns form. The software of Surfacer 10.5 to develop a new CAD software for fixed prosthetics, and the 3.5 axis numerical controlled machine to manufacture the prosthetics were used.

RESULTIt is the first time, the 3D graphic data bank of Chinese teeth crowns with a standard form was established. A software of the occlusal adjustment and the form modification were developed. It is also the first time, the authors realized the whole process to use the CAD-CAM for the manufacture of a crown.

CONCLUSIONThe successful result shows, that we have already mastered well the base theory, the mathematics method, the technology of a CAD-CAM system. It provides the basics for the future development.

Computer-Aided Design ; Dental Prosthesis Design ; methods ; trends ; Dental Restoration, Permanent ; methods ; Dentistry, Operative ; methods ; Humans ; Research ; trends ; Research Design

Objective To analyze the structural and phylogenetic characteristics of the mitochondrial genome from Bulinus globosus, so as to provide a theoretical basis for classification and identification of species within the Bulinus genus, and to provide insights into understanding of Bulinus-schistosomes interactions and the mechanisms of parasite transmission. Methods B. globosus samples were collected from the Ruya River basin in Zimbabwe. Mitochondrial DNA was extracted from B. globosus samples and the corresponding libraries were constructed for high-throughput sequencing on the Illumina NovaSeq 6000 platform. After raw sequencing data were subjected to quality control using the fastp software, genome assembly was performed using the A5-miseq and SPAdes tools, and genome annotation was conducted using the MITOS online server. Circular maps and sequence plots of the mitochondrial genome were generated using the CGView and OGDRAW software, and the protein conservation motifs and structures were analyzed using the TBtools software. Base composition and codon usage bias were analyzed and visualized using the software MEGA X and the ggplot2 package in the R software. In addition, a phylogenetic tree was created in the software MEGA X after sequence alignment with the software MAFFT 7, and visualized using the software iTOL. Results The mitochondrial genome of B. globosus was a 13 730 bp double-stranded circular molecule, containing 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and 13 protein-coding genes, with a marked AT preference. The mitochondrial genome composition of B. globosus was similar to that of other species within the Bulinus genus. Phylogenetic analysis revealed that the complete mitochondrial genome sequence of B. globosus was clustered with B. truncatus, B. nasutus, and B. ugandae into the same evolutionary clade, and gene superfamily analysis showed that the metabolism-related proteins of B. globosus were highly conserved, notably the cytochrome c oxidase family, which showed a significant consistency. Conclusions This is the first whole mitochondrial genome sequencing to decode the compositional features of the mitochondrial genome of B. globosus from Zimbabwe and its evolutionary relationship within the Bulinus genus, which provides important insights for further understanding of the phylogeny and mitochondrial genome characteristics of the Bulinus genus.