中国组织工程研究

中国组织工程研究 ›› 2011, Vol. 15 ›› Issue (29): 5347-5351.doi: 10.3969/j.issn.1673-8225.2011.29.007

• 材料生物相容性 material biocompatibility • 上一篇    下一篇

可吸收内固定材料L/DL-聚乳酸的体外降解特性

张  力1，熊成东2，吕春堂3   

  1. 1解放军沈阳军区总医院口腔颌面外科，辽宁省沈阳市110016
    2中科院成都有机化学研究所，四川省成都市 610041
    3解放军第二军医大学长海医院口腔科，上海市   200433
  • 收稿日期:2011-05-01 修回日期:2011-06-17 出版日期:2011-07-16 发布日期:2011-07-16
  • 作者简介:张力☆，男，1968年生，辽宁省锦州市人，汉族，2006年中国医科大学毕业，博士，主治医师，主要从事颌面部创伤及生物材料研究。 zhangli_024@yahoo.com.cn

Degradation of bioabsorbable fracture-fixation materials of poly (L/DL-lactide) in vitro

Zhang Li1, Xiong Cheng-dong2, Lü Chun-tang3   

  1. 1Department of Oral and Maxillofacial Surgery, General Hospital of Shenyang Military Area Command, Shenyang  110016, Liaoning Province, China
    2Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu  610041, Sichuan Province, China
    3Department of Stomatology, Changhai Hospital, Second Military Medical University of Chinese PLA, Shanghai  200433, China
  • Received:2011-05-01 Revised:2011-06-17 Online:2011-07-16 Published:2011-07-16
  • About author:Zhang Li☆, Doctor, Attending physician, Department of Oral and Maxillofacial Surgery, General Hospital of Shenyang Military Area Command, Shenyang 110016, Liaoning Province, China zhangli_024@yahoo.com.cn

PDF

814

被引次数

25

摘要：

背景：目前以左旋聚乳酸为代表的可吸收骨折内固定物已应用于临床，这种人工合成的高分子聚合物充分展示了其优越性，但同时也存在不足，限制了其广泛应用。
目的：评价可吸收内固定材料L/DL-聚乳酸的体外降解情况。
方法：将L/DL-聚乳酸试件置于37 ℃恒温的磷酸盐缓冲液中，在2，4，8，12，20，28周时间点取材，进行大体观察、扫描电镜观察、三点弯曲强度测定、重均分子质量检测并计算其降解率。另将相同试件置于蒸馏水中，于不同时间点测其pH值变化。
结果与结论：降解早期试件重均分子质量和机械强度下降较快，8周时重均分子质量降解了74.29%，机械强度衰减了60.99%，随后趋于平缓；对试件降解过程中抗弯强度衰减率和重均分子质量降解率进行双变量相关性分析，结果表明两者呈正相关性(r=0.958，P < 0.05)；pH值在20周后有较明显下降；L/DL-聚乳酸的降解腐蚀在其表面和内部几乎同时发生。提示L/DL-聚乳酸符合骨折内固定物的生物降解性和机械性能要求，有望在颌面外科领域应用。

关键词: 骨折内固定, 可降解, 聚乳酸, 可吸收, 生物材料

Abstract:

BACKGROUND: Several absorbable polymers for fracture internal fixation are in use nowadays predominantly. The best-known is L-polylactic acid, which is biocompatible and biodegradable and has good mechanical properties. Problems arising from insufficient strength and foreign body reaction are reasons why up till now these devices are not used more extensively in oral maxillofacial surgery.
OBJECTIVE: To evaluate the biodegradation of absorbable L/DL-polylactic acid (P(L/DL) LA) in vitro.
METHODS: The samples were subjected to aging at 37 ℃ in the phosphate buffered saline and instilled solution for 2, 4, 8, 12, 20 and 28 weeks. The macroscopic observation and scanning microscope were performed to evaluate the degradation of samples. The molecular weight, three-point bending strength and pH value were measured. The degradation rate was also investigated.
RESULTS AND CONCLUSION: There were 74.29% reduction of the molecular weight and 60.99% loss of mechanical property at 8 weeks. Double variables analysis was used to analyze the degradation rate of the molecular weight and the attenuation rate of the bending strength, results showed that the two were positively correlated(r=0.958, P < 0.05). Change of the pH was seen obviously after 20 weeks. Degradation of the samples was almost simultaneous on the out surface and in the center. It seems that the P(L/DL) LA has better mechanical properties and biodegradation. It is worth further medical research in oral maxillofacial surgery.

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