Division of Anatomy and Cell Biology of the Hard Tissue, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8514, Japan.
Int J Mol Sci. 2023 Feb 4;24(4):3124. doi: 10.3390/ijms24043124.
In our previous study we established an animal model for immediately placed implants using mice and clarified that there were no significant differences in the chronological healing process at the bone-implant interface between immediately and delayed placed implants blasted with hydroxyapatite (HA)/β-tricalcium phosphate (β-TCP) (ratio 1:4). This study aimed to analyze the effects of HA/β-TCP on osseointegration at the bone-implant interface after immediately placed implants in the maxillae of 4-week-old mice. Right maxillary first molars were extracted and cavities were prepared with a drill and titanium implants, blasted with or without HA/β-TCP, were placed. The fixation was followed-up at 1, 5, 7, 14, and 28 days after implantation, and the decalcified samples were embedded in paraffin and prepared sections were processed for immunohistochemistry using anti-osteopontin (OPN) and Ki67 antibodies, and tartrate-resistant acid phosphatase histochemistry. The undecalcified sample elements were quantitatively analyzed by an electron probe microanalyzer. Bone formation occurred on the preexisting bone surface (indirect osteogenesis) and on the implant surface (direct osteogenesis), indicating that osseointegration was achieved until 4 weeks post-operation in both of the groups. In the non-blasted group, the OPN immunoreactivity at the bone-implant interface was significantly decreased compared with the blasted group at week 2 and 4, as well as the rate of direct osteogenesis at week 4. These results suggest that the lack of HA/β-TCP on the implant surface affects the OPN immunoreactivity on the bone-implant interface, resulting in decreased direct osteogenesis following immediately placed titanium implants.
在我们之前的研究中，我们使用小鼠建立了一个即刻植入物的动物模型，并阐明在骨-植入物界面的时程愈合过程中，用羟基磷灰石（HA）/β-磷酸三钙（β-TCP）（比例 1:4）处理的即刻和延迟放置的植入物之间没有显著差异。本研究旨在分析 HA/β-TCP 对 4 周龄小鼠上颌骨中即刻放置植入物后骨-植入物界面骨整合的影响。切除右侧上颌第一磨牙，用钻头制备腔，放置钛植入物，并用或不用 HA/β-TCP 处理。在植入后 1、5、7、14 和 28 天进行固定随访，并对脱钙样本进行包埋，用抗骨桥蛋白（OPN）和 Ki67 抗体和抗酒石酸酸性磷酸酶组织化学处理制备切片，对未脱钙样本元素进行电子探针微量分析定量分析。在预先存在的骨表面（间接成骨）和植入物表面（直接成骨）发生骨形成，表明在两组中，直到术后 4 周都实现了骨整合。在未喷砂组中，与喷砂组相比，第 2 和 4 周时骨-植入物界面的 OPN 免疫反应性显著降低，第 4 周时直接成骨率也降低。这些结果表明，植入物表面缺乏 HA/β-TCP 会影响骨-植入物界面上的 OPN 免疫反应性，导致即刻放置钛植入物后直接成骨减少。
