Objective To introduce the application of platelet-rich plasma (PRP) in non-vascularised bone grafts (NVBG) of maxillofacial surgery and its potential mechanism in recent years.Methods The latest articles were extensively retrieved, and the potential mechanism for PRP promotes the osteogenesis was discussed. Results PRP promotes osteogenesis when applied to NVBG, and the cytokine included in platelet is thought to be the ingredient for PRP’s effect. Some scholar has already applied PRP in the restoration of maxillofacial bone defect andgot good results. Conclusion PRP has the potential to promotesosteogenesis, and more studies are needed for further understanding of its mechanism.
【Abstract】 Objective Through a retrospective study, to observe the cl inical therapeutic effect for closed reductiontreatment of developmental dislocation of the hip (DDH), and to dynamically analyze characteristics of acetabular development after closed reduction in DDH. Methods A total of 100 single side DDH children who were treated by “the treatment mode of closed reduction” from January 2002 to December 2005 were followed up, including 18 males and 82 females, with the average age of 19.4 months (ranging from 7 months to 36 months). Sixty-eight patients had left side dislocation, while 32 had right side dislocation. According to Zionts dislocation grades, 15 cases were degree I, 50 degree II, 26 degree III and 9 degree IV. Adductor tenotomies and skeletal traction were carried out in 74 cases, while direct closed reduction was performed in 26 cases. The four-level functional evaluation criterion was used to assess the cl inical therapeutic effect. Lesional and homeochronous normal hips were paired, and acetabular index (AI) and AI (D/W) of lesional and normal hips, before the reduction and in the 3rd, 6th, 9th and 12th month, respectively, after the reduction, were dynamically measured. Results The total choiceness rate of 100 children was 88.00%. Twelve months after the reduction, lesional AI decreased from (37.17 ± 2.17) º to (27.02 ± 3.54) º, while lesional AI(D/W) increased from 22.06% ± 1.65% to 29.80% ± 3.56%, and the differences among each time-point had statistical significance (P lt; 0.01). Both rates of lesional AI decrease and AI(D/W) increase were obviously faster than those of normal side physiological development (P lt; 0.01). In all durations after 12 months reduction, the rates of lesional AI were (3.22 ± 1.42) º and (3.41 ± 2.03) º in 1 - 3 months and 10 - 12 months , respectively, and the rates of AI(D/W) were 2.69% ± 1.83%and 2.33% ± 1.13%, respectively, and they were obviously faster than the other durations (P lt; 0.01). Both rates of lesional AI decrease and AI(D/W) increase were obviously faster than the homeochronous rate of normal side physiological development in each duration (P lt; 0.01). The rates of lesional AI were (13.71 ± 3.96) º and (11.48 ± 4.15) º in 7 - 12 age group and 13 - 18 age group, respectively, and the rates of AI(D/W) were 9.95% ± 3.81% and 8.28% ± 3.58%, respectively, and they wereobviously faster than the other age groups (P lt; 0.05). Both changes of lesional AI and AI(D/W) were obviously faster than the homeochronous changes of normal side in each age group(P lt; 0.01). Conclusion There are simple operating requirements and fine therapeutic effect of “the treatment mode of closed reduction” . Within 12-month after the closed reduction treatment, the rate of lesional acetabular development is obviously faster than that of normal side physiological development. The cresttime of lesional acetabular development is during 1 - 3 months and 10 - 12 months, and the best treatment time of closed reduction is the age before 18 months.
【Abstract】 Objective To construct tissue engineered skeletal muscle in vivo using glial cell derived neurotrophic factor (GDNF) genetically modified myoblast (Mb) on acellular collagen sponge with hypoglossal nerve implantation, and to observe whether structural or functional connection could be established between engineered tissue and motor nerve or not. Methods Mbs were isolated from 7 male Lewis rats at age of 2 days, cultured and genetically modified by recombinant adenovirus carrying GDNF cDNA (MbGDNF). Calf skin-derived acellular collagen sponge was used as scaffold; cell adhesion was detected by scanning electron microscope after 24 hours. Hypoglossal nerve was implanted into Mb-scaffold complex (Mb group, n=27) or MbGDNF-scaffold complex (MbGDNF group, n=27) in 54 female Lewis rats at age of 8 weeks. HE staining was performed at 1, 6, and 12 weeks postoperatively, and immunohistochemistry staining and fluorescence in situ hybridization were used. Results MbGDNF could highly expressed GDNF gene. Mb and MbGDNF could adhere to the scaffold and grew well. HE staining showed tight junctions between implant and peripheral tissue with new muscle fiber and no distinguished line at 12 weeks in 2 groups. Immunohistochemistry staining showed that positive cells of myogenin and slow skeletal myosin were detected, as well as positive cells of actylcholine receptor α1 at 1, 6, and 12 weeks. The positive cells of Y chromosome decreased with time. At 1, 6, and 12 weeks, the positive neurons were 261.0 ± 6.6, 227.3 ± 8.5, and 173.3 ± 9.1, respectively in MbGDNF group, and were 234.7 ± 5.5, 196.0 ± 13.5, and 166.7 ± 11.7, respectively in Mb group; significant differences were found between 2 groups at 1 and 6 weeks (P lt; 0.05), no significant difference at 12 weeks (P gt; 0.05). Conclusion Connection can be established between engineered tissue and implanted hypoglossal nerve. Recombinant GDNF produced by MbGDNF might play a critical role in protecting central motor neurons from apoptosis by means of retrograde transportation.