摘要
目的研究牙周再生膜在体外动态和静态降解体系中的降解性能。方法用聚乳酸乙醇酸制作的牙周再生膜在动态(降解介质流速为250μl/min)和静态两种降解体系中进行降解,分别在材料降解前的第0周和降解后的第1、2、4、6周测定牙周再生膜在体外动态和静态降解体系中的残存质量、平均分子量、弹性模量、孔隙率和渗透性的变化并对两种降解体系中的降解性能进行比较。结果降解过程中,牙周再生膜实验材料的质量随着降解的进行而不断损耗,残存的质量越来越少。实验材料的分子量随着降解的进行而不断减少。牙周再生膜的质量和分子量在静态降解体系中损失速度显著高于在动态降解体系(P<0.01);在两种实验条件下,牙周再生膜实验材料的弹性模量都是在第2周时开始上升,随后下降。材料的弹性模量在动态降解体系中较之静态降解体系能维持较长时间;无论在动态降解条件下,还是在静态降解条件下,实验材料的孔隙率都是从第2周时开始下降,而后逐渐增加。降解系统的状态对材料孔隙率变化的影响无显著差异(P>0.05);材料在静态降解体系中的渗透性显著高于动态降解体系(P<0.01)。材料在两种降解介质中的降解性能相似,但是在所测定的降解指标中,材料在人工唾液中的变化速度显著高于在PBS中的(0.01<P<0.05)。结论PLGA牙周再生膜体外降?
Object To study the degradation of PLGA film for periodontal guided tissue regeneration under static and dynamic biodegradable condition in vitro. Methods Periodontal guided tissue regeneration were fabricated using a copolymer of polylactide and polyglycolide. These films were subjected to degradation in phosphate buffered saline at 37℃ for up to 6 weeks under two test conditions: static and dynamic(flow 250μl/min). The degradable parameters were examined at 1 weeks, 2 weeks, 4 weeks and 6 weeks with 8 pieces of GTR film each. Results During the degradation , the mass and molecular weight of the GTR film decreased gradually. The mass and molecular weight of the GTR film exhibited a steady decrease up to 6 weeks. The effects of dynamic and static conditions on mass and molecular weight were significant(P<0.01).The porosity of the GTR film decreased up to 2 weeks and then increased, while the elastic molulus first increased and then decreased over the course of the study. The effects of dynamic and static conditions on mass, permeability and molecular weight were significant(P<0.01). However, the effects of dynamic and static conditions on porosity were not very evident(P>0.05). The degradable process was similar with the GTR film degraded both in the PBS and the artificial saliva. The degradable index measured in this research changed more rapidly in the artificial saliva than that in the PBS(0.01<P<0.05). Conclunsion In vitro degradation of PLGA film is mainly a chemical degradation process. The dynamic degradation condition decreased the degradation rate significantly. Different body fluids such as artificial saliva changes will affect the degradation kinetics of the material.
出处
《上海生物医学工程》
2005年第1期28-32,共5页
Shanghai Journal of Biomedical Engineering
