BACKGROUND:Oversize stress of a dental implant and its surrounding tissue is the main factor to affect the
long-term use of dental implants. So, the reasonable and precise design of implant shape is one of the important methods of prolonging the life span of dental implants.
OBJECTIVE:To make the optimal analysis and design of the diameters of connector screw and central screw of the adjustable-angle dental implant invented in the earlier stage.
METHODS: The finite element analysis model of the edentulous mandible with adjustable-angle dental implant was established by software Pro/E 5.0, Mimics 10.0 and ANSYS Workbench 14.5. The maximum equivalent
stress of dental implant-edentulous mandibular model was analyzed.
RESULTS AND CONCLUSION:The maximum equivalent stress of dental implant-edentulous mandibular model

Objective To investigate the expression of miRNA-140 in chondrocytes and synovial fluid of osteoarthritis (OA) patients, and explore the relationship between the miRNA-140 expression and OA severity.Methods This study enrolled 30 OA patients who underwent total knee arthroplasty for chondrocytes sampling and 30 OA patients who underwent intra-articular injection for synovial fluid sampling. All OA patients were grouped into mild [Kellgren and Lawrence (KL) grade 1-2], moderate (KL grade 3) and severe (KL grade 4), with 10 in each subgroups for each sampling purposes. 7 non-OA patients and 10 patients with knee injury were collected for cartilage and synovial fluid sampling respectively as control groups. Chondrocytes were isolated from the cartilage tissue and cultured in vitro. Quantitative real time PCR for miRNA-140 in chondrocytes and synovial fluid were performed, and the U6 snRNA was used as internal control. The expression difference of miRNA-140 among groups and correlation between the expression and the KL grade of OA were analysed using one-way ANOVA and Spearman test respectively. Results The expression of miRNA-140 in chondrocytes of knees in OA patients was reduced than that in normal knees, and the between-group difference was statistically significant (F=305.464, P<0.001). miRNA-140 could be detected in synovial fluid of both normal knees and OA knees, its relative expression level was reduced in synovial fluid of OA group compared with normal group, and the between-group difference was statistically significant as well (F=314.245, P<0.001). The relative expression level of miRNA-140 in both chondrocytes and synovial fluid were negatively correlated with the KL grade of OA(r=-0.969, P<0.001; r=-0.970, P<0.001). Conclusion miRNA-140 could be detected in chondrocytes and synovial fluid of OA patients, and its expression was negatively correlated with the severity of OA.
Adult ; Aged ; Cells, Cultured ; Chondrocytes ; metabolism ; Female ; Humans ; Knee Joint ; metabolism ; Male ; MicroRNAs ; analysis ; Middle Aged ; Osteoarthritis, Knee ; metabolism ; Real-Time Polymerase Chain Reaction ; Synovial Fluid ; metabolism