Department of Biomaterials, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
Clin Oral Implants Res. 2013 Feb;24(2):210-6. doi: 10.1111/j.1600-0501.2012.02421.x. Epub 2012 Feb 15.
The aim of this pre-clinical study was to evaluate the biological performance of two injectable calcium phosphate cement (CPC) composite materials containing poly(D,L-lactic-co-glycolic)acid (PLGA) microspheres with different properties in a maxillary sinus floor elevation model in sheep.
PLGA microspheres were made of either low molecular weight (17 kDa) acid-terminated PLGA (PLGA(L-AT) ) or high molecular weight (44 kDa) end-capped PLGA (PLGA(H-EC) ) and incorporated in CPC. Eight female Swifter sheep underwent a bilateral maxillary sinus floor elevation procedure via an extra-oral approach. All animals received both materials, alternately injected in the left and right sinus (split-mouth model) and a time point of 12 weeks was used. Analysis of biological performance was based on histology, histomorphometry, and evaluation of sequential fluorochrome labeling.
Both types of CPC-PLGA composites showed biocompatibility and direct bone-cement contact. CPC-PLGA(L-AT) showed a significantly higher degradation distance compared to CPC-PLGA(H-EC) (1949 ± 1295 μm vs. 459 ± 267 μm; P = 0.0107). Further, CPC-PLGA(L-AT) showed significantly more bone in the region of interest (26.4 ± 10.5% vs. 8.6 ± 3.9% for PLGA(H-EC) ; P = 0.0009) and significantly less remaining CPC material (61.2 ± 17.7% vs. 81.9 ± 10.9% for PLGA(H-EC) ; P = 0.0192).
Both CPC-PLGA(L-AT) and CPC-PLGA(H-EC) demonstrated to be safe materials for sinus floor elevation procedures in a large animal model, presenting biocompatibility and direct bone contact. In view of material performance, CPC-PLGA(L-AT) showed significantly faster degradation and a significantly higher amount of newly formed bone compared to CPC-PLGA(H-EC) .
本临床前研究旨在评估两种不同性能的含聚（D，L-乳酸-共-乙醇酸）（PLGA）微球的可注射磷酸钙水泥（CPC）复合材料在绵羊上颌窦底提升模型中的生物学性能。
PLGA 微球由低分子量（17 kDa）端酸基 PLGA（PLGA（L-AT））或高分子量（44 kDa）端封端 PLGA（PLGA（H-EC））制成，并掺入 CPC 中。八只雌性斯威夫特羊通过口腔外途径进行双侧上颌窦底提升手术。所有动物均同时接受两种材料的治疗，分别注射于左侧和右侧窦（分侧模型），并在 12 周时进行分析。生物学性能的分析基于组织学、组织形态计量学和氟标记的顺序分析。
两种类型的 CPC-PLGA 复合材料均表现出良好的生物相容性和直接的骨-水泥接触。CPC-PLGA（L-AT）的降解距离明显大于 CPC-PLGA（H-EC）（1949±1295 μm 比 459±267 μm；P=0.0107）。此外，CPC-PLGA（L-AT）在感兴趣区域的骨量明显更多（26.4±10.5%比 PLGA（H-EC）的 8.6±3.9%；P=0.0009），而剩余 CPC 材料明显较少（61.2±17.7%比 PLGA（H-EC）的 81.9±10.9%；P=0.0192）。
在大型动物模型中，CPC-PLGA（L-AT）和 CPC-PLGA（H-EC）均被证明是安全的鼻窦底提升材料，具有良好的生物相容性和直接的骨接触。就材料性能而言，与 CPC-PLGA（H-EC）相比，CPC-PLGA（L-AT）的降解速度明显更快，新形成的骨量明显更多。
