Wildburger Angelika, Bubalo Vladimir, Magyar Marton, Nagursky Heiner, Jakse Norbert, Schmelzeisen Rainer, Sauerbier Sebastian
1 Department of Oral Surgery and Orthodontics, School of Dentistry, Medical University of Graz , Graz, Austria .
2 Division of Biomedical Research, Medical University of Graz , Graz, Austria .
Tissue Eng Part C Methods. 2017 Jul;23(7):404-411. doi: 10.1089/ten.TEC.2016.0549.
The aim of the present split-mouth study in sheep was to assess the influence of in situ hardening properties of a biphasic calcium phosphate (BCP) bone graft substitute (BGS) (ratio hydroxyapatite/β-tricalcium phosphate = 60/40) compared with a particulate BGS with the same biphasic core-granule composition without in situ hardening properties on sinus floor augmentation.
Therefore, bilateral sinus floor augmentation was performed in eight sheep. Poly(lactide-co-glycolide) (PLGA)-coated, in situ hardening biphasic BGS (PLGA-NMP [N-Methyl-2-pyrrolidone]-BCP) was placed at the test site, and a particulate biphasic BGS without PLGA coating (BCP) was used for the contralateral site as a control. Animals were sacrificed after 21 weeks. Sinus augmentation sites were analyzed histologically. The volume was analyzed by computed tomography. Histomorphometric parameters were assessed for the 12 and 21 weeks' time points. Slopes of new bone formation over time were compared with a linear growth regression model.
Bone formation after 12 and 21 weeks of healing was 8.94% (±3.74) and 19.82% (±6.29) for PLGA-NMP-BCP and 7.00% (±2.58) and 14.38% (±4.51) for BCP, respectively. The bone growth rate for PLGA-NMP-BCP was higher than the growth rate for BCP (probability 97.5%). The total fraction of calcified hard tissue (% bone fraction + % biomaterial) was around 46% for both tested biomaterials, 21 weeks after sinus floor augmentation.
The in situ hardening BGS (PLGA-NMP-BCP) performed better than the particulate material (BCP) in terms of bone formation rate. The in situ hardening properties of the PLGA-NMP-BCP material mediated by the PLGA coating and NMP solution as plasticizer had no negative influence on the bone formation.
本项在绵羊身上进行的双侧对照研究旨在评估一种双相磷酸钙（BCP）骨移植替代物（BGS）（羟基磷灰石/β-磷酸三钙比例为60/40）的原位硬化特性与一种具有相同双相核心颗粒组成但无原位硬化特性的颗粒状BGS相比，对鼻窦底提升的影响。
因此，对8只绵羊进行了双侧鼻窦底提升术。将聚（丙交酯-共-乙交酯）（PLGA）涂层的原位硬化双相BGS（PLGA-NMP[N-甲基-2-吡咯烷酮]-BCP）放置在试验部位，对侧部位使用无PLGA涂层的颗粒状双相BGS（BCP）作为对照。21周后处死动物。对鼻窦提升部位进行组织学分析。通过计算机断层扫描分析体积。评估12周和21周时间点的组织形态计量学参数。使用线性生长回归模型比较随时间的新骨形成斜率。
愈合12周和21周后，PLGA-NMP-BCP的骨形成分别为8.94%（±3.74）和19.82%（±6.29），BCP的骨形成分别为7.00%（±2.58）和14.38%（±4.51）。PLGA-NMP-BCP的骨生长速率高于BCP（概率97.5%）。鼻窦底提升21周后，两种受试生物材料的钙化硬组织总分数（%骨分数+%生物材料）约为46%。
原位硬化BGS（PLGA-NMP-BCP）在骨形成率方面比颗粒材料（BCP）表现更好。由PLGA涂层和作为增塑剂的NMP溶液介导的PLGA-NMP-BCP材料的原位硬化特性对骨形成没有负面影响。
