Department of Periodontology and Oral Mucosa, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA.
J Periodontal Res. 2018 Aug;53(4):514-524. doi: 10.1111/jre.12541. Epub 2018 Apr 6.
Impaired bone formation of the buccal alveolar plate after tooth extraction during adolescence increases the difficulty of future implant restoration. This study was undertaken to assess the feasibility and efficacy of transplanting autogenous scaffold-free culture-expanded mesenchymal stem cell (MSC) sheets to the buccal alveolar bone surface to stimulate local bone growth.
Mandibular bone marrow was aspirated from 3-month-old pigs (n = 5), from which MSCs were isolated and culture expanded. Triple-layer MSC sheets were then fabricated using temperature-responsive tissue culture plates. One month after bone marrow aspirations, the same pigs underwent bilateral extraction of mandibular primary molars, immediately followed by transplantation of 3 autogenous triple-layer MSC sheets on to the subperiosteal buccal alveolar surface of 1 randomly chosen side. The contralateral side (control) underwent the same periosteal reflection surgery without receiving MSC sheet transplantation. Six weeks later, the animals were killed and specimens from both sides were immediately harvested for radiographic and histological analysis. Buccal alveolar bone thickness, tissue mineral density (TMD), mineral apposition and bone volume fraction (BV/TV) were quantified and compared between the MSC sheet and control sides using paired t-tests.
Triple-layer MSC sheets were reliably fabricated and the majority of cells remained vital before transplantation. The thickness of buccal bone tended to increase with MSC sheet transplantation (P = .18), with 4 of 5 animals showing an average of 1.82 ± 0.73 mm thicker bone on the MSC sheet side than the control side. After being normalized by the TMD of intracortical bone, the TMD of surface cortical bone was 0.5-fold higher on the MSC sheet side than the control side (P < .05). Likewise, the BV/TV measurements of the buccal surface region were also 0.4-fold higher on the MSC sheet side than the control side (P < .05) after being normalized by measurements from the intracortical region. Mineral apposition measurements were not different between the 2 sides.
Mandibular marrow-derived MSCs can be fabricated into cell sheets and autogenous transplantation of MSC sheets onto the subperiosteal buccal alveolar bone surface at the tooth-extraction site may increase local bone density.
青少年时期拔牙后颊牙槽板的成骨功能受损，增加了未来种植修复的难度。本研究旨在评估将自体无支架培养扩增间充质干细胞（MSC）片移植到颊牙槽骨表面以刺激局部骨生长的可行性和疗效。
从 3 月龄猪（n=5）下颌骨抽吸骨髓，分离培养 MSC。然后使用温度响应组织培养板制备三层 MSC 片。骨髓抽吸后 1 个月，同一头猪双侧下颌乳磨牙拔除，立即将 3 个自体三层 MSC 片移植到一侧骨膜下颊牙槽表面。对侧（对照）进行相同的骨膜反射手术，但不接受 MSC 片移植。6 周后处死动物，立即从两侧采集标本进行放射学和组织学分析。使用配对 t 检验比较 MSC 片侧和对照侧的颊牙槽骨厚度、组织矿密度（TMD）、矿化沉积率和骨体积分数（BV/TV）。
可靠地制备了三层 MSC 片，移植前大多数细胞仍保持活力。颊骨厚度倾向于随 MSC 片移植而增加（P=0.18），5 只动物中有 4 只动物在 MSC 片侧的骨厚度比对照侧平均厚 1.82±0.73mm。经皮质骨内 TMD 校正后，MSC 片侧表面皮质骨的 TMD 是对照侧的 0.5 倍（P<0.05）。同样，经皮质内测量校正后，MSC 片侧颊侧表面区域的 BV/TV 测量值也比对照侧高 0.4 倍（P<0.05）。矿化沉积率测量值在两侧之间无差异。
下颌骨髓源性 MSC 可制成细胞片，自体 MSC 片移植到拔牙部位的骨膜下颊牙槽骨表面可能会增加局部骨密度。
