Early Osseointegration of Implants with Cortex-like TiO2 Coatings Formed by Micro-arc Oxidation: A Histomorphometric Study in Rabbits / 华中科技大学学报（医学）（英德文版）

In our previous studies,a novel cortex-like TiO2 coating was prepared on Ti surface through micro-arc oxidation (MAO) by using sodium tetraborate as electrolyte,and the effects of the coating on cell attachment were testified.This study aimed to investigate the effects of this cortex-like MAO coating on osseointegration.A sand-blasting and acid-etching (SLA) coating that has been widely used in clinical practice served as control.Topographical and chemical characterizations were conducted by scanning electron microscopy,energy dispersive X-ray spectrometer,X-ray diffraction,contact angle meter,and step profiler.Results showed that the cortex-like coating had microslots and nanopores and it was superhydrophilic,whereas the SLA surface was hydrophobic.The roughness of MAO was similar to that of SLA.The MAO and SLA implants were implanted into the femoral condyles of New Zealand rabbits to evaluate their in-vivo performance through micro-CT,histological analysis,and fluorescent labeling at the bone-implant interface four weeks after surgery.The micro-CT showed that the bone volume ratio and mean trabecular thickness were similar between MAO and SLA groups four weeks after implantation.Histological analysis and fluorescent labeling showed no significant differences in the bone-implant contact between the MAO and SLA surfaces.It was suggested that with micro/nanostructure and superhydrophilicity,the cortex-like MAO coating causes excellent osseointegration,holding a promise of an application to implant modification.

Duraplasty with Neuropatch versus autologous fascia lata for Chiari I malformation with syringomyelia: A comparative study / 北京大学学报(医学版)

Objective: To evaluate the outcome and postoperative reaction of dural substitute (Neuropatch) applying in the treatment of Chiari I malformation(CMI) associated with syringomyelia(SM). Methods:Forty patients of CMI associated with SM were operated in our department from Jul. 2002 to Jul. 2004. All patients underwent posterior cranial fossa decompression and duraplasty. They were divided into two groups, 20 patients being repaired with Neuropatch (Neuropatch group), and the others with autologous fascia lata (fascia group). There were 6 males and 14 females in Neuropatch group and 10 males and 10 females in fascia group. The operations were performed under general anesthesia via suboccipital approach and the extent of posterior cranial fossa decompression ranged from 20 cm2 (5 cm×4 cm) to 35 cm2 (5 cm×7 cm). The removal of posterior arch of atlas depended on the extent of tonsillar herniation, and the dura was opened in Y shape. The Neuropatch was cut into triangular shape, and the same sized autologous fascia lata was used in fascia group. The patches were sutured tightly to the dura matter in each group. The incision was closed layer by layer and drainage was used, if necessary. Antibiotics and hormone were routinely used. The duration of operation, postoperative fever were evaluated, the outcome of the operation was evaluated by Tator scale, and the data were analyzed with statistic software SPSS 10.0. Results: There were12 patients (60%) who suffered from postoperative fever in the Neuropatch group, and 9 patients (45%) in the fascia group(χ2=0.902,P=0.342). Seventeen patients in each group were improved postoperatively. The duration of operation, postoperative fever and antibiotics used were compared between the two groups. No significant difference was found, but the duration of postoperative fever and the time of hormone used were different. There were no postoperative infections that occurred after the follow up for 1 to 2 years, except for one patient in fascia group who developed infective granuloma and recovered later by treatment. Conclusion: Neuropatch is a useful dural substitute for the repair of dural defects in the treatment of CMI associated with syringomyelia.