An In Vivo Study on the Biocompatibility of a Bioresorbable Poly(L-lactide-co-glycolide) Pin for Bone Fixation

可吸收式PLGA骨固定物之體內生物相容研究

林永昇(Yung-Sheng Lin) ； 奉季光(Chi-Kuang Feng) ； 葉獻彬(Shia-Bin Ye) ； 林玉如(Yu-Ju Lin) ； 陳進富(Chin-Fu Chen) ； 廖俊仁(Chun-Jen Liao) ； 張根源(Ken-Yuan Chang) ； 蔡瑞瑩(Ruey-Yug Tsay)

《Journal of Medical and Biological Engineering》 21卷4期 (2001/12) Pp. 233-242

摘要

PLA/PGA高分子之無毒性及生物可降解性造就了它們應用於骨固定器之無限遠景，然而它們的降解行為在它們應用的成敗上佔有重要之影響。PLA/PGA高分子之降解特性不只與高分子本身之性質有關，加工的過程也會對它的降解特性有所影響。因此在發展骨科矯形器時，有必要對經特定加工程序成形之聚酯類固定器，進行生物相容性測試。本研究針對工研院製作出來用於骨固定之可吸收PLGA，進行其生物相容性測試，其原料高分子分別由工研院自行合成或購自PURAC。實驗以成熟紐西蘭白兔為對象，分別植入其背部肌群、腿部肌群及遠端股骨骨髓腔三處進行，並比較此三處之差異。兩組不同PLGA原料之試樣的組織反應都在植入後1到5個月間進行分析。結果顯示兩組PLGA都具良好之組織相容性，發炎反應都相當緩和。PLGA取出物的形態觀察，則顯示其降解為由外往內的表面侵蝕形式，此結果與文獻上報導，大於3 mm的PLGA材料，在體外降解時的由內往外降解的方式大為不同，此結果顯示一般以類生理緩衝液浸泡之體外降解之實驗，並不能適當地模擬PLGA材料真實體內降解之環境。

關鍵字

PLGA ； 生物相容性 ； 體內

並列摘要

The non-toxic and biodegradable natures of the PLA/PGA polymers provide themselves with a promising future in the application of bone fixation devices. The degradation behavior of the PLA/PGA polymers plays an important role in the decisive performance of its use. Because the degradation properties of a PLA/PGA specimen depend not only on the properties of a polymer used but also on its fabrication process, it is necessary to test the biocompatibility of the polyester specimens of the ”as used” devices in the development of an orthopedic fixation device. This study assesses the biocompatibility of a bioresorbable PLGA pin used for bone fixation manufactured by the Industrial Technology Research Institute (ITRI). Two polymers, one purchased from PURAC and one synthesized by ITRI, were used as the raw materials for processing. These pins were placed in three regions, the interstices of dorsal muscle, the interstices of gluteal muscle and the bone marrow cavity of distal femur of adult New Zealand white rabbits, to compare the tissue responses of different implant sites. Tissue responses evaluated for 1 to 5 months reveal that both groups of PLGA pins are tissue tolerant and their inflammation reactions are quite mild. Morphology observations of the retrieved samples indicate that these PLGA pins degrade by surface erosion in vivo. It is different from the heterogeneously degradation pattern, which progresses from the interior to exterior of the implants, reported in the literatures for in vitro tests. This result suggests that the regular incubation conditions applied for in vitro study do not properly simulate the in vivo degradation behavior of the implants.

並列關鍵字

PLGA ； Biocompatibility ； In vivo