[A clinical analysis of screw-retained implant-supported casted integrated abutment crowns in the molar region with limited interocclusal space].

PURPOSE: To observe the clinical effects of screw-retained implant-supported casted abutment integrated crowns (IACs) in the molar region with limited interocclusal space. METHODS: This study involved 507 implants in 376 patients with limited interocclusal space in the molar region. All implants were inserted to the jaw by standard one-stage protocol. Screw-retained IACs were used as the final prosthesis. With 6 to 24 months follow-up, the clinical effects of screw-retained IACs were recorded and analyzed using SPSS 17.0 software package. RESULTS: During 6 to 24 months of follow-up, the implant survival rate was 99.61%. 37 patients had ceramic fracture which mainly happened in the group with 3-4 mm interocclusal space. In each group, porcelain fused to metal (PFM) prosthesis had ceramic fracture more easily than PFM prosthesis without porcelain on occlusal surface(P<0.05). As the interocclusal space became smaller, the probability of collapsing porcelain increased(P<0.05).13 patients had screw loosening. 13 patients suffered from gingival swelling and bleeding, they were given periodontal treatment and oral hygiene instruction. Patients were satisfied with the restoration results. CONCLUSIONS: Screw-retained IACs can be used to repair missing teeth in the molar region with limited interocclusal space.

[Effect of miR-21 in promoting angiogenesis differentiation of umbilical cord blood mesenchymal stem cells in vitro].

PURPOSE: To investigate the effect of miR-21 on promoting vascular differentiation of umbilical cord blood derived mesenchymal stem cells (UCBMSCs) in vitro. METHODS: UCBMSCs (from Stem Cell Bank of Tongji University) were cultured; Lenti-LacZ-Luciferase and Lenti-miR-21-Luciferase Lentiviral vector were reconstructed; Real-time fluorescence quantification PCR and Western blot were performed to detect the expression of key angiogenic factors at 0, 1, 4, 7 and 14 d after target gene was transduced into UCBMSCs; UCBMSCs of the third generation were transduced with Lenti-LacZ-Luciferase and Lenti-miR-21- Luciferase; matrigel tube assay was performed to observe the tube-like structure under microscope. The data were statistically analyzed using Student's t test and variance analysis with SPSS13.0 software package. RESULTS: UCBMSCs were successfully cultured; The results of qPCR and Western blot showed the expression of HIF-1α and VEGF in miR-21 group significantly increased at 4 d and continued until 7 d and 14 d; Matrigel results showed the tubular structures in Lenti-miR-21-Luciferase group were more than other groups both in amount and in length. CONCLUSIONS: MiR-21 can promote vascular differentiation of UCBMSCs.

[Application of one-piece implant-supported detachable telescope retained fixed bridge in edentulous cases].

PURPOSE: To evaluate the clinical effectiveness of one-piece implant-supported detachable telescopic fixed bridge in edentulous patients. METHODS: Seventeen patients were treated with one-piece implant-supported detachable telescopic fixed bridge. A total of 18 prostheses were fabricated with 8 in the upper jaws and 10 in the lower jaws.Fixed bridges retained by telescopic crowns were used as final prostheses, with milling titanium or all-ceramic abutments as primary crowns, gold-electroforming crowns as secondary crowns. Surveys about clinical and radiographic examination, satisfaction and prosthetic complications were conducted after 3 months,1 year, 2 years, 3 years after final rehabilitation. Data analysis was performed using SPSS 17.0 software package. RESULTS: Radiography showed stable bone levels for all implants except 2 implants, which were observed slight marginal bone resorption. The results of one-way ANOVA showed that no significant difference in modified plaque index or modified sulcus blooding index was found during the follow-up period (P>0.05). The probing attachment level deteriorated by 1.5 mm during the first 3 years (P<0.05). Eighteen restoration provided sufficient fixation and stability. Two porcelain fractures occured but had no influence on restoration. The patients were highly satisfied with the outcomes. The frequency of prosthetic maintenance per patient per year was 0.11. CONCLUSIONS: One-piece implant-supported detachable telescopic fixed bridge is an effective method with satisfactory long-term aesthetic and stable outcomes in edentulous patients.