Chinese Journal of Tissue Engineering Research ›› 2011, Vol. 15 ›› Issue (29): 5347-5351.doi: 10.3969/j.issn.1673-8225.2011.29.007

Previous Articles     Next Articles

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

850

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.

CLC Number: