ABSTRACT
Guided bone regeneration (GBR) uses resorbable and non-resorbable membranes as biological barriers. This study compared the differences in hard tissue stability between GBR using evidence-based digital titanium mesh and resorbable collagen membranes during implant placement. A total of 40 patients (65 implant sites) were enrolled and divided into two groups: resorbable membrane and digital titanium mesh groups. The alveolar bone was analyzed at two- and three-dimensional levels using cone-beam computed tomography and by reconstructing and superimposing the hard tissues at four time points: preoperatively, postoperatively, before second-stage surgery, and 1 year after loading. The use of digital titanium mesh showed less alveolar bone resorption in vertical and horizontal directions two-dimensionally before the second-stage surgery and 1 year after loading. Regarding volumetric stability, the percentage of resorption after 6 months of healing with resorbable membrane coverage reached 37.5%. However, it was only 23.4% with titanium mesh. Although postoperative bone volume was greater at all labial sites with resorbable membrane than with digital titanium mesh, after substantial bone resorption within 1 year of loading, the labial bone thickness at the upper part of implants was thinner with resorbable membrane than with digital titanium mesh. Furthermore, digital titanium meshes made according to ideal bone arch contour reduced soft tissue irritation, and the exposure rate was only 10%. Therefore, although both resorbable membrane and digital titanium mesh in GBR were able to successfully reconstruct the bone defect, digital titanium meshes were better at maintaining the hard tissue volume in the osteogenic space.
Subject(s)
Humans , Bone Regeneration , Bone Resorption , Osteogenesis , Surgical Mesh , TitaniumABSTRACT
Objective:To investigate the usability of TLC as a evaluating method for adriamycin liposome stability by separating its composition and degradation products with TLC and improve this method. Methods:The plates were developed twice with four development systems,visualized by 4-methoxybenzaldehyde. Results:It was better to separate EPC,cholesterol and their degradation products by using chloroform-methanol-water-ammonia(65∶35∶2.5∶2.5) as the mobile phase. Conclusion:TLC could be used for the quality control of the adriamycin liposome due to its simple operation and high reproducibility.
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OBJECTIVE: To draw a comparison between the two preparative technologies of tetrandrine liposomes. METHODS: Tetrandrine liposomes were prepared with ammonium sulfate transmembrane gradient method and film dispersion method respectively. Leaking ratio,particle size,and content of phospholipid of liposomes were selected as the parameters to indicate the stability of liposomes,and the entrapment efficiency was taken as quality index to compare the two preparation technologies. RESULTS: Tetrandrine liposomes prepared with ammonium sulfate transmembrane gradient technology achieved high entrapment efficiency of 81.1% and good stability,while those prepared by film dispersion method had an entrapment efficiency of only 32.9% with poor stability. CONCLUSION: Ammonium sulfate transmembrane gradient method is feasible and superior to the film dispersion method in the preparation of tetrandrine liposome.
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OBJECTIVE: To determine the concentration of phospholipid in 5-FUR prodrug liposome. METHODS: The sample was fragmented by ethanol and extracted by chloroform. The concentration of phospholipid in 5-FUR prodrug liposome was determined by ammonium ferrothiocyarate spectrophometry at a wavelength 488 nm. RESULTS: The linear range of phospholipid was 0.01～0.10 mg?mL-1(r=0.999 6, n=3) with an average recovery rate of 99.66% (RSD=3.17%). CONCLUSION: This method is simple, convenient and sensitive, and it can be used for the quality control of 5-FUR prodrug liposome.
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Objective To develop a kind of system of simulation and training on ECG for studying ,training and assessing of biomedical engineer. Methods The simulation training system was designed based on PC. In the hardware system, ADuC848 SCM was adopted as the primary controller, QuickStart exploration platform was used to develop firmware, and intelligent assessing system was explored by C++ Builder. Results Biomedical Engineer could be trained, checked and evaluated by the system. Conclusion The system, combining practice and examination, pays attention to basic skill training and thus improves studying efficiency.